Genome skimming elucidates the evolutionary history of Octopoda

Phylogenies for Octopoda have, until now, been based on morphological characters or a few genes. Here we provide the complete mitogenomes and the nuclear 18S and 28S ribosomal genes of twenty Octopoda specimens, comprising 18 species of Cirrata and Incirrata, representing 13 genera and all five putative families of Cirrata (Cirroctopodidae, Cirroteuthidae, Grimpoteuthidae, Opisthoteuthidae and Stauroteuthidae) and six families of Incirrata (Amphitretidae, Argonautidae, Bathypolypodidae, Eledonidae, Enteroctopodidae, and Megaleledonidae) which were assembled using genome skimming. Phylogenetic trees were built using Maximum Likelihood and Bayesian Inference with several alignment matrices. All mitochondrial genomes had the 'typical' genome composition and gene order previously reported for octopodiforms, except Bathypolypus ergasticus, which appears to lack ND5, two tRNA genes that flank ND5 and two other tRNA genes. Argonautoidea was revealed as sister to Octopodidae by the mitochondrial protein-coding gene dataset, however, it was recovered as sister to all other incirrate octopods with strong support in an analysis using nuclear rRNA genes. Within Cirrata, our study supports two existing classifications suggesting neither is likely in conflict with the true evolutionary history of the suborder. Genome skimming is useful in the analysis of phylogenetic relationships within Octopoda; inclusion of both mitochondrial and nuclear data may be key.

Abstract PD18-11: Dose-Expansion Study of Trastuzumab Deruxtecan as Monotherapy or Combined With Pertuzumab in Patients With Metastatic Human Epidermal Growth Factor Receptor 2-Positive (HER2+) Breast Cancer in DESTINY-Breast07 (DB-07)

Background: In trials of HER2+ metastatic breast cancer (mBC), trastuzumab deruxtecan (T-DXd) monotherapy showed durable efficacy (DESTINY-Breast01) and significantly prolonged progression-free survival vs trastuzumab emtansine (DESTINY-Breast03). T-DXd is approved in the US for patients with HER2+ unresectable/mBC who received ≥1 prior anti-HER2–based treatment (tx) in the metastatic or neo-/adjuvant setting and recommended for approval in the EU as 2nd-line tx. Preclinical data suggest that T-DXd used in combination with other anticancer tx may lead to improved efficacy. The purpose of DB-07 is to assess the safety and efficacy of T-DXd alone or with other anticancer tx for patients with HER2+ mBC. Here we report preliminary data from the DB-07 dose-expansion phase for T-DXd monotherapy and T-DXd + pertuzumab (P) as 1st-line (1L) tx in mBC.

Methods: DB-07 (NCT04538742) is an ongoing, phase 1b/2, 2-part (part 1: dose finding; part 2: dose expansion), modular, open-label trial of T-DXd alone or with other anticancer tx in patients with HER2+ mBC. In part 2, patients in module (mod) 0 received T-DXd 5.4 mg/kg every 3 weeks (Q3W) and in mod 2, T-DXd 5.4 mg/kg + P 420 mg Q3W (loading dose: 840 mg), the recommended phase 2 dose. Patients in these mods must be mBC tx naive. For part 2, the primary objective is to assess safety and tolerability. A secondary objective is to assess the objective response rate (ORR) per local investigators by Response Evaluation Criteria In Solid Tumors v1.1. We report results for patients randomized before Oct 13, 2021 to mods 0 and 2 of part 2 (data cutoff [DCO]: Mar 4, 2022); recruitment is ongoing. Based on the distinct mechanism of action of T-DXd and P, we conducted preclinical studies with the drugs in HER2-overexpressing cell lines to elucidate their potential synergies. To assess the effects on T-DXd internalization, live cell imaging was performed using pH-dependent fluorescently labeled T-DXd. To assess the effects on HER2 signaling, total and p-HER2 levels and downstream substrates were evaluated by immunoblot.

Results: 23 patients were enrolled in the T-DXd monotherapy mod; 20 (87.0%) were receiving tx and 3 (13.0%) discontinued tx (withdrawal by patient, n=2; adverse event [AE], n=1) by DCO. 22 patients were enrolled in the T-DXd + P mod; 20 (90.9%) were receiving tx and 2 (9.1%) discontinued tx (AE, n=1; disease progression, n=1) by DCO. All patients experienced AEs (Table); 1 patient in each mod died. The unconfirmed ORR (80% CI) with T-DXd monotherapy and T-DXd + P was 82.6% (68.2%-92.2%) and 77.3% (61.9%-88.5%), respectively; updated data will be presented. Preclinical studies showed that T-DXd was more rapidly and effectively internalized in combination with P than when administered alone. Immunoblotting of cell lysates showed a greater reduction in total HER2 and HER2 signaling in response to combination tx than with T-DXd or P alone.

Discussion: In summary, 1L T-DXd monotherapy and T-DXd + P safety profiles and antitumor activity were consistent with those previously reported for T-DXd. Mature data in these mods are awaited, and other T-DXd combinations are being investigated in additional mods. Preclinical studies showed the potential for P to induce greater internalization of T-DXd and inhibition of HER2-driven signaling. These results support investigation of T-DXd in larger ongoing trials (eg, NCT04784715).

Table 1: Summary of treatment duration and safety data

Citation Format: Erika Hamilton, Komal Jhaveri, Sherene Loi, Carey Anders, Peter Schmid, Konstantin Penkov, Elena Artamonova, Lyudmila Zhukova, Daniil L. Stroyakovsky, Dinesh Chandra Doval, Rafael Villanueva, Flavia Michelini, Sarat Chandarlapaty, Matt Wilson, Sarice R. Boston, Adam Konpa, Shoubhik Mondal, Fabrice Andre. Dose-Expansion Study of Trastuzumab Deruxtecan as Monotherapy or Combined With Pertuzumab in Patients With Metastatic Human Epidermal Growth Factor Receptor 2-Positive (HER2+) Breast Cancer in DESTINY-Breast07 (DB-07) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD18-11.

Abstract P4-07-38: Real-world data of Advanced Breast Cancer (ABC) patients with HER2-positivity before the second-line therapy: data from the observational study GEICAM/2014-03 (RegistEM)

Background: Over the last years, the treatment of HER2-positive (HER2+) breast cancer (BC) patients (pts) has been changing because of the development of new anti-HER2 agents. In the current analysis, we describe the features, treatment patterns, progression-free survivall (PFS) and overall survival (OS) outcomes of BC pts with HER2 + (immunohistochemistry [IHC] 3+ or IHC 2+ and in situ hybridization [ISH]+), following ASCO/CAP 2018 guidelines in the most recent tumor lesion before the 2nd-line.

Methods: The RegistEM study is an ongoing BC registry study that is providing prospective data from around 1900 pts diagnosed with advanced BC (ABC) between 01/Jan/2016 and 31/Dec/2019, in 38 Spanish institutions from GEICAM network. In this analysis, 296 HER2+ BC pts have been included, representing the 18% of pts available in the database at the cut-off date (08/Apr/2022), with ABC diagnosis before 2019 (n=1559).

Results: At first ABC diagnosis, 58% (n=173) pts had recurrent disease (>36 months [mo] from initial BC diagnosis in 62%), 41% (n=120) de novo metastatic BC and 1% (n=3) unresectable locally ABC (ULABC); the median age was 58 years, 68% were postmenopausal and there was only 1 male pt. From total 296 pts, 66% had hormone receptor expression [HR+]; the BC subtype was assessed in tumor tissue from the breast (58%) or a metastatic lesion (34%), and in 8% pts, HER2 positivity was observed after the 1st-line. Family history of BC and/or ovarian cancer was reported in 28% pts, and a hereditary-risk genetic test was performed in 26% pts (n=74/282). Germline BRCA1/2 and TP53 genetic testing were reported in 14 and 26 pts respectively, being mutated in 3/14 (21%) and 5/26 (19%) pts. Bone (50%), lymph nodes (49%), liver (35%), lung (31%), soft tissue (8%) and central nervous system (CNS), mostly in brain (8%), were the main metastatic sites. One hundred pts were diagnosed with CNS metastases: 24 at baseline, 48 during the 1st-line and 28 in subsequent lines. Additional data according to HR status and type of ABC are detailed in the table below, showing a worse prognosis in absence of HR expression. In HR- pts, bone metastases were less frequent and lymph nodes metastases more frequent compared to HR+ pts. Visceral disease was present in 69% (66% in HR+ and 74% in HR-; non-statistically significant) pts and ≈80% had ≤3 (54%, ≤2) locations involved. The most common therapies by line were: 1) 1st-line: Chemotherapy (CT) + biological therapy (BT) (38%), CT + BT+ endocrine therapy (ET) (35%), and ET + BT [11%]; 2) 2nd-line: BT (55%), CT + BT (20%) and ET + BT (15%); 3) 3rd-line: CT + BT (49%) and BT (31%). The median (95% confidence interval [CI]) progression-free survival (PFS) on 1st, 2nd and 3rd line was 18 (15-22), 8 (7-9) and 6 (5-8) mo, respectively. The median (95% CI) overall survival (OS) from ABC diagnosis was 43 (40-49) mo. These survival outcomes were higher in HR+ pts, however, the differences were only statistically significant in OS (p=0.006; log-rank). At database cut-off date, death was reported in 47% pts.

Conclusions: In spite of the anti-HER2 therapies administered in the advanced setting, the HR expression is a relevant prognostic factor, with a clinically and statistically significant impact in OS, improving the outcomes of HR+ pts.

The soft X-ray monochromator at the SASE3 beamline of the European XFEL: from design to operation

The SASE3 soft X-ray beamline at the European XFEL has been designed and built to provide experiments with a pink or monochromatic beam in the photon energy range 250-3000 eV. Here, the focus is monochromatic operation of the SASE3 beamline, and the design and performance of the SASE3 grating monochromator are reported. The unique capability of a free-electron laser source to produce short femtosecond pulses of a high degree of coherence challenges the monochromator design by demanding control of both photon energy and temporal resolution. The aim to transport close to transform-limited pulses poses very high demands on the optics quality, in particular on the grating. The current realization of the SASE3 monochromator is discussed in comparison with optimal design performance. At present, the monochromator operates with two gratings: the low-resolution grating is optimized for time-resolved experiments and allows for moderate resolving power of about 2000-5000 along with pulse stretching of a few to a few tens of femtoseconds RMS, and the high-resolution grating reaches a resolving power of 10 000 at the cost of larger pulse stretching.

B-esterases characterisation in the digestive tract of the common octopus and the European cuttlefish and their in vitro responses to contaminants of environmental concern

Cephalopods are a group of marine invertebrates that have received little attention as sentinel species in comparison to other molluscs, such as bivalves. Consequently, their physiological and biochemical xenobiotic metabolism responses are poorly understood. Here we undertake a comparative analysis of the enzymatic activities involved in detoxification reactions and neural transmission in the digestive tract of two commercial cephalopods: the Common octopus, Octopus vulgaris, and the European cuttlefish, Sepia officinalis. For methodological purposes, several common B-esterases (five carboxylesterase (CE) substrates and three cholinesterase (ChE) determinations) were assayed as a proxy of metabolic and neuronal activities, respectively. Four components of the digestive tract in each species were considered: salivary glands, the stomach, the digestive gland and the caecum. The in vitro responses of digestive gland homogenates to model chemicals and contaminants of environmental concern were contrasted between both cephalopod species. The baseline biochemical activities in the four digestive tract components were also determined. Moreover, in order to validate the protocol, purified proteins, recombinant human CE (CE1 and CE2) and purified eel acetylcholinesterase (AChE) were included in the analysis. Overall, carboxylesterase activities were higher in octopus than in cuttlefish, with the activity quantified in the digestive tract components in the following order: digestive gland ≈ caecum > stomach ≈ salivary glands, with higher hydrolysis rates reached with naphthyl-derived substrates. In contrast, cuttlefish hydrolysis rates with ChE substrates were higher than in octopus. This trend was also reflected in a higher sensitivity to CE inhibitors in octopus and to AChE inhibitors in cuttlefish. Given the detoxification character of CEs and its protective role preventing AChE inhibition, octopus could be regarded as more efficiently protected than cuttlefish from neurotoxic exposures. A full characterisation of B-esterases in the digestive tract of the two common cephalopods is also provided.

Phase 1b/2 study of ladiratuzumab vedotin (LV) in combination with pembrolizumab for first-line treatment of triple-negative breast cancer (SGNLVA-002, trial in progress)

TPS1127

Background: Patients with metastatic triple-negative breast cancer (mTNBC) have a poor prognosis. Treatment combinations of anti-programmed death ligand 1 (anti–PD-L1) agents with chemotherapy have shown promise in mTNBC. LV is an investigational antibody–drug conjugate directed to LIV-1, a protein highly expressed on breast cancer cells, via a humanized IgG1 monoclonal antibody conjugated to monomethyl auristatin E (MMAE) by a protease-cleavable linker. LIV-1–mediated delivery of MMAE disrupts microtubules and induces cell cycle arrest and apoptosis. LV has also been shown to drive immunogenic cell death (ICD) to elicit an immune response. LV + pembrolizumab may result in synergistic activity through LV-induced ICD, creating a microenvironment favorable for enhanced anti–PD-L1 activity. Preliminary results show LV delivered once every 3 weeks (Q3W) + pembrolizumab was tolerable with encouraging antitumor activity in patients with mTNBC (Han 2019). Additionally, interim results of weekly LV monotherapy at doses up to 1.5 mg/kg were clinically active and generally well tolerated (Tsai 2021). Based on pharmacokinetic and pharmacodynamic modeling and simulation analysis, an intermittent LV + pembrolizumab dosing regimen is being evaluated to further enhance efficacy and improve the tolerability profile. Due to an unmet medical need for patients with mTNBC who are PD-L1 low or negative, Part D will focus on this patient population. Methods: SGNLVA-002 (NCT03310957) is an ongoing global single-arm, open-label phase 1b/2 study of LV + pembrolizumab as 1L therapy for patients with unresectable locally advanced/mTNBC. Part D is currently enrolling ̃40 patients. Eligible patients must have advanced disease with no prior cytotoxic/anti–PD-L1 treatment, PD-L1 combined positive score < 10, measurable disease per RECIST v1.1 and an ECOG score ≤1. Patients with Grade ≥2 pre-existing neuropathy or active central nervous system metastases are not permitted. Patients will receive LV at 1.5 mg/kg on Days 1 and 8 plus pembrolizumab 200 mg on Day 1 Q3W. The primary objectives are to evaluate the safety/tolerability and objective response rate of LV + pembrolizumab. Secondary objectives include duration of response, disease control rate, progression-free survival, and overall survival. Safety and efficacy endpoints will be summarized with descriptive statistics. Global enrollment is ongoing in the US, EU, and Asia. Clinical trial information: NCT03310957.

Outcomes of patients (pts) treated with novel immunotherapy (IT) agents in phase 1 clinical trials (Ph1-CT) at early lines for advanced disease

2581

Background: The overall survival (OS) benefit observed with immune checkpoint inhibitors led to their approval in many tumor types. Given the large number of IT compounds in early clinical development, many pts are offered IT within Ph1-CT even before having exhausted standard of care (SOC) therapies. We assessed outcomes of pts receiving novel IT treatments within Ph1-CT at the Phase 1 Unit of Catalan Institute of Oncology (ICO), Barcelona, Spain. Methods: We retrospectively reviewed a correlative series of pts with advanced/metastatic solid tumors treated with IT within Ph1-CT at ICO from January 2018 to June 2021. Primary endpoint was to assess clinical outcomes measured by median progression-free survival (mPFS) and median OS (mOS) according to number of prior lines (PL) for recurrent/metastatic disease, grade 3-4 toxicity (G3-4 Tox) and age. Data on prior IT (yes vs no) and availability of alternative SOC were evaluated. Overall response rate (ORR) was assessed according to RECIST 1.1. Clinical benefit rate (CBR) was defined as complete/partial response + stable disease for ≥6 months (m). PFS/OS were calculated by Kaplan-Meier method. Log-rank test was used for comparisons. Median PFS of alternative SOC according to historical data was recorded by tumor type and line of treatment. Results: A total of 104 pts received IT within Ph1-CT: IT monotherapy = 39 (37.5%), IT combinations = 65 (62.5%) (IT+IT = 59 [90.8%], IT+targeted therapy = 6 [9.2%]). Median age was 54 y (42-77), 62.5% were men and all had ECOG 0-1. Four most frequent cancers were urothelial (19.2%), colorectal (15.3%), head & neck (12.5%) and glioblastoma (11.5%). Number of PL: 0 = 20 (19.2%) pts, 1 = 37 (35.6%) pts, ≥2 = 47 (45.2%) pts. Nine (8.6%) pts had received prior IT. G3-4 Tox rate for the overall population was 19.2% and for pts who had received prior IT was 33%. ORR was 11.5%; CBR was 24%. Overall mPFS and mOS were 2.7m and 8.6m, respectively. Pts with less PL had greater mPFS and mOS (p < 0.05) (Table). Pts with available alternative SOC had lower mPFS but similar mOS compared to historical SOC (2.6m vs 4.8m, 11.4m vs 11.8m, respectively). G3-4 Tox (yes vs no) and age ( < 70 vs ≥70) did not significantly impact on mOS or mPFS (p = 0.18 and p = 0.83, respectively). At end of Ph1-CT treatment, 47 (45.2%) pts worsened their ECOG status, 15 (14.4%) pts were enrolled in a subsequent trial and 22 (21.1%) pts received SOC. Conclusions: In our cohort of pts treated with novel IT within Ph1-CT, overall clinical outcomes were modest in terms of mPFS, mOS, and CBR. However, pts with less pre-treated tumors seem to achieve higher survival benefit from early treatment with IT within Ph1-CT, although this benefit remains unclear in pts with alternative SOC. [Table: see text]

Analysis of phase I clinical trials (Ph1-CT) new enrollment patterns in the immuno-oncology era

e14549

Background: Immuno-Oncology (IO) has revolutionized anticancer therapeutics and changed the early drug development paradigm. Positive results and limited access to IO drugs in some countries have led to increased enrollment in IO Ph1-CT at an earlier timepoint in patients (pts) disease journey. We evaluated the impact of IO era on enrollment patterns in Ph1-CT. Methods: We retrospectively reviewed pts with recurrent/metastatic solid tumors enrolled in Ph1-CT from January 2018 to June 2021 at the Phase 1 Unit of Catalan Institute of Oncology (ICO), Barcelona, Spain. The primary goal was to assess Ph1-CT enrollment patterns, including use of molecular pre-screening/personalized drug matching, and the availability of alternative standard of care (SOC). Overall response rate (ORR) was assessed according to RECIST 1.1. Clinical benefit rate (CBR) was defined as complete/partial response+stable disease for ≥6 months. Median progression-free survival (mPFS) and overall survival (mOS) using Kaplan-Meier method were provided. Results: A total of 175 pts were enrolled in Ph1-CT. Median age was 54 years (range 43-75), Male:Female = 99:76, 99% had ECOG 0-1. The most prevalent tumors were: 32 (18%) breast, 31 (18%) colorectal, 25 (14%) urogenital and 23 (13%) glioblastoma multiforme. One hundred forty-six (83%) pts were enrolled in Ph1-CT with IO (alone or in combination) and 29 (17%) pts with targeted therapy (TT). Molecular pre-screening tests were required in 24 (14%) pts (22 pts IO vs 2 pts TT trial). Eleven (42%) pts were pre-screening failures. Screening failure (SF) rate was 19%, the main reason being clinical worsening for 7 (4%) pts. Thirty-three (19%) pts had an alternative SOC treatment available at time of enrollment. One hundred two (58%) pts had received ≤1 prior lines and 26 (89%) were IO-naïve. Finally, 129 (74%) out of 175 pts enrolled were treated within Ph1-CT. Out of 129 treated pts, ORR was achieved in 18 (14%) pts (3% complete response) and 44 (34%) had stable disease. CBR was observed in 36 (28%) pts. mPFS was 2.8 months and mOS was 10.9 months. Toxicity grade 3-4 occurred in 25 (19%) of pts and 6 (5%) pts had to interrupt treatment. Seventy-one (55%) pts received subsequent therapies: 22 (17%) in Ph1-CT; 49 (38%) SOC. Eleven (9%) pts received IO as subsequent therapy. Decline in ECOG status (baseline vs end of treatment) occurred in 65 (50%) pts. Conclusions: In our cohort of Ph1CT pts, there has been an increasing number of pts enrolled in IO trials compared to TT. Most pts received treatment within Ph1-CT at an earlier timepoint in the course of their disease (1st or 2nd lines). Our results suggest a clear impact of the IO era on the trends of Ph1-CT availability and enrollment patterns.

Rationale and design of phase 1 FTIH study of FOXP3 antisense oligonucleotide AZD8701 in patients with selected advanced solid tumors

TPS3166

Background: The forkhead box family transcription factor FOXP3 is essential for T regulatory cells (Tregs) development and immune suppressive function. Tregs are an integral component of the adaptive immune system and contribute to maintaining tolerance to self-antigens and preventing autoimmune diseases. In the context of cancer, however, Tregs contribute to tumor progression by suppressing antitumor immunity. To date inhibition of Treg-mediated immunosuppression tested in the clinic has lacked specificity. Targeting FOXP3 provides a selective approach to impair the immunosuppressive function of Tregs but targeting transcription factors has been a challenge using conventional drug modalities. AZD8701 employs next-generation antisense oligonucleotide (ASO) technology (Ionis Pharmaceuticals) to bind mRNA with high affinity and selectively reduce human Foxp3 mRNA expression levels. Foxp3-specific ASOs promote potent dose-dependent reductions in Foxp3 mRNA and protein in vitro. In preclinical models, AZD8701 induced Foxp3 knockdown results in Tregs with a reduced immunosuppressive capacity, loss of immunosuppressive markers, and increased markers of activation on CD8+ T-cells. AZD8701 reduces tumor growth as monotherapy in preclinical models and increased tumor inhibition is obtained by combining AZD8701 with a PD-L1 inhibitor. Methods: This is a Phase I multicenter study of AZD8701 alone or in combination with durvalumab in participants with selected advanced solid tumors. Eligible patients must have ECOG performance status 0 or 1, measurable target lesion per RECIST v1.1 and be diagnosed with selected tumor types as described below. Monotherapy and combination dose escalation phase is open for participants with head and neck squamous cell carcinoma (HNSCC), triple-negative breast cancer (TNBC), non-small-cell lung cancer (NSCLC), clear cell renal cell carcinoma (ccRCC), gastroesophageal cancer, melanoma, cervical cancer, small-cell lung cancer (SCLC), and/or solid tumors that have demonstrated a response to prior programmed death-ligand-1 (PD-[L]1) treatment (as defined by duration of response > 18 weeks). Participants with NSCLC, HNSCC, TNBC, and ccRCC will be included in the pharmacodynamic cohort at the selected monotherapy dose and/or disease expansion cohorts. The primary objectives are to assess safety and tolerability and to determine the preliminary antitumor activity of AZD8701 (objective response rate) when administered as monotherapy or in combination with durvalumab. Secondary endpoints include, disease control rate, duration of response, progression free survival and overall survival, pharmacokinetics and pharmacodynamics (including changes in Foxp3 mRNA in paired tumor samples). The trial is currently recruiting. Clinical trial information: NCT04504669.

Abstract P1-08-26: Morphologic characterization of tumor-infiltrating lymphocytes and its relation with pathological response in a series of breast cancer patients treated with primary chemotherapy

Introduction: Tumor-Infiltrating Lymphocytes (TILS) is a well-known predictor of response to primary chemotherapy1,2 and a prognostic factor for improved survival in different breast cancer subtypes3. We present data on the association of the level of TILs and morphologic characteristics of such infiltrate with pCR. Material and methods: A series of 477 breast cancer patients (479 tumors) treated with primary chemotherapy at Catalan Institut of Oncolgy - H.U. Bellvitge between January 2009 and December 2016. Chemotherapy consisted on anthracyclines and taxanes (plus trastuzumab if Her-2 positive disease). Levels of percentage of TILs using hematoxylin-eosin-stained sections of diagnostic core-needle biopsy were evaluated according to international guidelines in a prospectively defined retrospective analysis. Characterization of TILS consisted on identification of plasma cells, intraepithelial infiltrate vs stromal infiltrate and homogeneous vs heterogeneous infiltrate. A sub-classification using levels of TILS and heterogeneity was done for statistical purposes. Levels of TILS and their morphological characteristics were examined for their associations with pCR adjusted for predictive clinic-pathological factors, by univariate and multivariate logistic regression, statistical significance set at 0.05. A ROC curve was performed to look for a cut-point of TILs to predict PCR. Results: The mean value of TILs was 23.79% (SD, 24%). TILs were significantly higher in ductal carcinomas (39.1% vs 0%, p=0.007), grade 3 (55.2 vs 17.7%p&lt;0.001), ki 67 &gt;30 (48.8% vs 24.5%, p&lt;0.001), HER2 (56.6%) and triple negative tumors (TNBC)(56.6%) vs luminal (20%), p&lt;0.001). The level of TILS was set in 20% to predict pCR by a ROC curve (S=62.3% E=71%). Characterization of TILs found plasma cells in 41.1% of the samples, intraepithelial infiltrate in 11.2% and homogeneous infiltrate in 60.1%. Homogeneously high infiltrate was found in 20% of the samples. In the univariate analysis pCR was higher in samples with TILs &gt; 20% (15.2% vs 41.5%, OR: 3.96 [95%CI, 2.57-6.10]; P &lt; 0.001); plasma cells (OR 6.61 [95%CI, 1.51-28.8]; P=0.01), intraepithelial TILS (OR: 10.34 [95%CI, 2.22-48.01]; P =0.003), homogeneous high infiltrate (OR: 13.6 [95%CI, 3.04-60.77]; P =0.001). In luminal tumors, TILs over 20% predicted pCR (OR 12.3 [95%CI, 4.0-37.7]; P &lt; 0.001) as well as in TNBC (OR 4.32 [95%CI, 1.77-10.53]; P=0 .001) but not in those cases with HER2 positive tumors (luminalB HER2 + HER2) (OR 1.65 [95%CI, 0.88-3.07]; P=0.118). In the multivariate analyses, levels of TILs &gt; 20% were associated with higher pCR rates (adjusted odds ratio, 2.44 [95%CI, 1.48-4.01]; P &lt; .001). Conclusions: The presence of TILs over 20% at diagnosis is an independent, positive, predictive marker of pCR in early breast cancer treated with neoadjuvant chemotherapy. Interestingly, the predictive information added by TILs &gt;20% was higher in luminal and triple negative tumors compared to HER2 positive cases. Careful morphological characterization of TILS may add valuable predictive information and can be done in current pathologic laboratories with a well-trained breast cancer pathologist. References: 1.J Clin Oncol 2009; 28:105-113. doi: 10.1200/JCO.2009.23.73702.JAMA Oncol. 2015;1(4):448-454. doi:10.1001/jamaoncol.2015.08303.Lancet Oncol 2018: 19: 40-50 http://dx.doi.org/10.1016/S1470-2045(17)30904-X.

N%Age years (mean, sd)Grade*I326.7II19540.7III15152.6Ki 67≤3020442.6&gt;3027557.4Molecular subtype*Luminal A469.6Luminal B HER2 -14329.9Luminal B HER2+9219.2HER+ enriched7615.9Triple negative12225.5Pathologic responseNon-pCR35874.7pCR12125.3

Citation Format: Catalina Falo, Juan Azcarate, Ana Petit, Andrea Vethencourt, Sergi Fernandez Gonzalez, Amparo Garcia-Tejedor, Silvia Vazquez, Hector Perez, Maria Laplana, Charo Taco, Esther Guerra, Anna Guma, Raul Ortega, Agostina Stradella, Sabela Recalde, Adela Fernandez-Ortega, Rafael Villanueva, F Javier Perez, M Jesus Pla, Miriam Campos, Diana Perez, Eulalia Fernandez-Montoliu, Veronica Obadia, Monica Cejuela, Miguel Gil-Gil, Sonia Pernas, Mar Varela, Teresa Soler-Monzo. Morphologic characterization of tumor-infiltrating lymphocytes and its relation with pathological response in a series of breast cancer patients treated with primary chemotherapy [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-08-26.

Abstract P5-07-06: Genomic characterization and tumor evolution in matched(primary-relapse)samplesof patients with METAPLASTIC breast cancer

Introduction and objectives. Metaplastic breast cancer is an heterogenous and infrequent disease (0.5-2%). Histologically, it is defined by differentiation of neoplastic epithelium into squamous or mesenchymal-like elements. Although they are mainly triple negative tumors, they present a more aggressive course with less response to chemotherapy and worse prognosis. The aim of our study was to characterize the molecular profile and tumor evolution in matched (primary-relapse) samples of patients (pts) with metaplastic breast cancer. Material and Methods. Genomic profiling of tumor biopsies from different time points in patients with early-stage metaplastic breast cancer who had disease recurrence/progression, and were treated at our institution between 2010 and 2020. Tumor samples were analyzed by DNA- Next Generation Sequencing (NGS; Illumina 2x75bp) using the ActionOncoKitDX panel (Imegen-Health in Code group). It allowed the study of point mutations in 50 genes, CNVs, fusion genes among 8 genes and pharmacogenetic SNPs associated with treatment efficacy or toxicity. It also determined MSI through 110 markers. The results were classified following the recommendations of the ACMG (American College of Medical Genetics). Only pathogenic and likely pathogenic variants were considered for analysis and afterwards we categorized them following the ComPerMed (The Personalized Medicine Commission) criteria. Results. We have analyzed 21 matched diagnosis-relapse tumor samples (8 primary tumor samples, and 13 loco-regional or metastatic disease) from 8 patients. In 4 patients, genomic characterization was performed at 3 different time points of their tumor evolution. Pathogenic alterations identified were mutations in TP53 (in 100% of the samples), TERT promoter (29%), and MYC amplifications (24% of samples, of which 75% were relapse/progression samples). We didn’t find any mutation in PI3KCA, but PTEN was found to have variations in 38% samples (10% mutations and 38% deletions). Amplification of FGFR1 was identified in 13% of the pts (only in the primary tumor). No ERBB2 or EGFR gene amplifications were detected, neither high grade MSI. We did not find a significant increase in point mutations between primary and relapse/progression samples, although gene amplifications were found more frequently in the former ones. Sixty three percent of the cases were Tier I and II category alterations, which could have future implications in the management of this neoplasia. Conclusion. In our series of metaplastic carcinoma, the most frequent pathogenic alterations occurred in cycle regulation’s genes, including TP53 and TERT promoter mutations, and MYC amplifications. Relapse/progression samples were enriched in MYC amplification and inTP53 allelic frequency. Larger studies are required to better characterize these tumors, and identify new strategies to improve the prognosis of these patients.

Citation Format: Mónica Cejuela, Agostina Stradella, Anna Petit, Pablo Gargallo, Jan Bosch, Paula Carbonell, Sabela Recalde, Andrea Vethencourt, Adela Fernández, Catalina Falo, Miguel Gil-Gil, Silvia Vazquez, Rafael Villanueva, Teresa Soler, Inés Calabria, Sonia Pernas. Genomic characterization and tumor evolution in matched(primary-relapse)samplesof patients with METAPLASTIC breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-07-06.

Abstract P1-15-04: Features of HER2+ metastasic patients (pts) from a prospective registry of advanced breast cancer (ABC), GEICAM/2014-03 (RegistEM)

Background: The RegistEM study is a non-interventional study that is providing prospective data from around 1900 ABC pts (females and males) diagnosed with advanced disease between 01/Jan/2016 and 31/Dec/2019, either after recurrence or at 1st diagnosis, in 38 Spanish sites representative of the national territory and whose investigators are GEICAM members. Methods: In the current analysis (cut-off date 10/May/2021, ongoing database), we describe the features of 279 pts included in the RegistEM study, with HER2+ (immunohistochemistry [IHQ] 3+, IHQ 2+ and in situ hybridization [ISH]+) tumors at any time of their ABC (5% after the 1st-line therapy). This subgroup has been evaluated because of the interest from a clinical perspective. Multivariate Cox analysis aiming to identify factors associated with overall survival (OS) were built. Results: 279 pts were identified, representing the 15% pts available in the database at the cut-off date. At first ABC diagnosis, 48% pts had recurrent BC (&gt;12 months [mo] from initial BC diagnosis in 93%), 51% de novo metastatic BC and 1% unresectable locally advanced BC (ULABC). The median age was 59 years, 98% were white , 71% postmenopausal and only 1 male was part of this subset. Considering the BC subtype assessed in the most recent tumor lesion before the 1st-line therapy, 264 pts wereHER2 positive (67% with hormone receptor [HR]+). Family history of BC and/or ovarian cancer was reported in 31% pts, and an hereditary-risk genetic test was performed in 25% (66/267 pts). BRCA1/2 and TP53 mutations were reported in 4/20 and 4/19 pts, respectively, and p53 overexpression in 20/46 pts. Lymph nodes (56%), bone (49%), liver (34%), lung (33%), soft tissue (10%) and brain (8%) were the main metastatic sites. Additional data according to HR status and type of ABC are detailed in the table below. In HR- pts, bone metastases were less frequent and lymph nodes metastases more frequent compared to HR+ pts. Visceral disease was present in 68% pts and ≈75% had ≤3 (47% ≤2) locations involved. The most common therapies by line were: 1) 1st-line: CT + dual anti-HER2 blockade (3%), chemotherapy (CT) (almost in all pts taxane-based)+dual anti-HER2 blockade + endocrine therapy (ET) (mainly aromatase inhibitors) (35%), and ET + anti-HER2 blockade or ET + cyclin-dependent kinases 4/6 inhibitors (11%); 2) 2nd-line: anti-HER2 blockade (56%) [mostly an antibody-drug conjugate (90%)], CT + anti-HER2 blockade (18%) and ET + anti-HER2 blockade (14%); 3) 3rd-line: CT + anti-HER2 blockade (55%) and anti-HER2 blockade (22%). The median time-to-progressions to 1st-, 2nd- and 3rd-line were 14, 5, and 4 mo, respectively. A 4th-line therapy was reported in 52% of pts who received a 3rd-line. At database cut-off date, death was reported in 34% of pts. The median OS of this subset of pts was 41 mo (36-49). In a multivariate Cox regression analysis, the following variables were significantly related with worse survival (from ABC diagnosis): Brain (HR=2.62; 95% CI, 1.02-6.73) and Visceral no Brain involvement (HR=2.15; 95% CI, 1.02-4.53) compare to only soft tissue lesions; early stage at first diagnosis (HR=1.77; 95% CI, 1.15-2.73); HR- (HR=1.70; 95% CI, 1.11-2.60) and age (HR=1.04; 95% CI, 1.02-1.07). Conclusions: In this cohort of HER2+ pts with advanced disease, half of them had de novo ABC which was associated with better OS. The median PFS in 1st- and 3rd-line were slightly better in HR+ pts, and in 2nd-line was similar between HR+ and HR- cohorts.

HR+181 (67%)HR- 91 (33%)Recurrent EBC134 (48%)ULABC or de novo M1 145 (52%)Time to recurrence &gt;12 mo in EBC pts., n8435125NALocation of metastaticsites, nBoneBrainLiverLungLymph nodesSoft tissue104 10 62 57 90 1829 9 3232 64 1059 15 36 47 51 2278 6 59 46 1056Líne123123123123n180935690492613385521446333Deaths, n211112111161715141584Therapies by line, nET/BT261922101910212100ET12441011022323CT/BT/ET935031038305830CT/BT4017307581552182366924CT3572353711211BT6431373651145143385The most frequent therapies, nCT + dual anti-HER2 blockade + ET8623331551CT + single-agent HER2 blockade + ET522CT + dual anti-HER2 blockade3493644391016252CT + single-agent HER2 blockade4825641588211521CT5573354711411ET*22105212162644ET + HER2 blockade1213411662782Anti-HER2 blockade6431073651145143382Median duration of treatment, mo125585310441064TTP (mo), median (range)15(1-47)5(1-32)5(0-18)11(2-38)5(1-27)4(2-12)12 (1-47)5(1-26)4(0-17)17(2-45)7(1-32)4(1-18)Median PFS, mo14561154------HR: hormone receptor; EBC: early breast cancer; ULABC: unresectable locally advanced breast cancer; M1: metastatic; mo: month; ET: endrocrine therapy; BT: biological therapy; CT: chemotherapy; TTP: time-to-progression; PFS: progression-free survival. *ET includes aromatase inhibitors or selective estrogen receptor degraders, as single-agents or combined with cyclin-dependent kinases 4/6 inhibitors.

Citation Format: Isabel Álvarez, Ángel Guerrero-Zotano, Josefina Cruz, Purificación Martínez, María Hernández, César A Rodríguez, Álvaro Rodríguez-Lescure, Silvia Antolín, Encarna Adrover, Raquel Andrés, Catalina Falo, Jose Ignacio Chacón, Ana Miguel, Sonia Servitja, Maria Galán Gramaje, Mireia Margelí Vila, César Gómez Raposo, María Jose Echarri, Rafael Villanueva, Ariadna TIbau Martorell, Silvia Varela Ferreiro, Ruth Campo, Juan Jose Miralles, Susana Bezares, Federico Rojo, Sara López-Tarruella. Features of HER2+ metastasic patients (pts) from a prospective registry of advanced breast cancer (ABC), GEICAM/2014-03 (RegistEM) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-15-04.

Abstract P2-08-10: First results of the randomized window of opportunity clinical trial D-Biomark: Immunomodulatory effect of denosumab in early breast cancer

Background: Most breast cancers (BC) exhibit low immune infiltration and are unresponsive to immunotherapy. Inhibitors of the Receptor Activator of NFkB (RANK) pathway, such as denosumab, used for the treatment of bone metastasis, have been shown to prevent BC, reducing tumor cell proliferation and survival. Our recent data supports that RANK pathway inhibition in BC cells enhances anti-tumor immune response. However, the population of BC patients who may benefit from denosumab remains to be identified. The aim of the study is to evaluate the antiproliferative, proapoptotic and/or immunomodulatory activity of denosumab in early BC and to identify biomarkers of response. Methods: Patients with early stage HER2-negative BC, candidates to tumor excision as first therapeutic approach were included. Patients were randomized 2: 1 to denosumab (two doses of 120mg/Kg subcutaneous denosumab, days 1 and 8 plus oral calcium 1000 mg daily for a month) and control arm (no treatment). Blood and tumor samples were collected at baseline and at surgery (2-4 weeks later). Putative changes in tumor cell proliferation by Ki67 immunohistochemistry (IHC), survival by Cleaved caspase-3 IHC and tumor infiltrating lymphocytes (TILs) quantified in H&E were evaluated between initial biopsy and surgery. RANK and RANKL expression will be analysed by IHC and the infiltrating immune populations will be characterized by specific antibodies (CD3, CD4, CD8, CD20, FoxP3, CD68, PDL1, PD1). We will analyse denosumab driven gene expression changes in tumor samples and tools such as CIBERSORT will be used to characterize the immune infiltrate. To assess the increase in TILs and the variation in Ki 67 and Cleaved caspase-3, the T-test for paired samples was used. A value of p less than 0.05 was defined as statistically significant. Result: We present results from the initial 45 patients enrolled out of 60, 31 cases in the experimental arm and 13 in the control arm. Mean age was 55,97 (range 37-88) years. 38 women with luminal breast cancer were analysed and 7 cases of triple negative BC (5 in experimental arm and 2 in control arm). Clinical and tumor characteristics were well balanced between both groups. No relevant toxicities were reported. There was no reduction of Ki67 in either of the two arms and no changes in Cleaved caspase-3 were observed. Interestingly, a statistically significant increase in TILs was observed in the denosumab treated group (p=0.0092, Paired t test) but not in the control group (p=0.68). 29.03% of patients treated with denosumab showed a ≥10% increase in TILs vs 7.14% in the control group (p=0.13). Denosumab was associated with an effective systemic inhibition of RANKL. No relationship was found between serum RANKL levels at baseline and response to denosumab. RNAseq analysis and immunophenotyping is still in progress. Conclusion: Short term neoadjuvant denosumab induces an immunomodulatory effect with an increase in stromal TILs in early BC. ClinicalTrials.gov Identifier: NCT03691311

Table 1.ResultsBiopsySurgeryKi 67 (mean frequency) Control24.5729.57Ki 67 (mean frequency) Experimental22.3927.90Cleaved caspase 3 (mean area) Control0.260.58Cleaved caspase 3 (mean area) Experimental0.350.42TILs (mean percentage) Control9.3410.29TILs (mean percentage) Experimental8.2913.54TILs incrementControl p=0.68 vs. Experimental p=0.009

Citation Format: Andrea Vethencourt, Eva M Trinidad, Anna Petit, María T Soler-Monsó, Clara Gómez Aleza, Ander Urruticochea, Amparo García-Tejedor, Anna Gumà Martinez, Veronica Obadia, Silvia Vazquez, Rafael Villanueva, Adela Fernánez, Monica Cejuela, Sabela Recalde Penabad, Agostina Stradella, Miguel Gil-Gil, Sonia Pernas, Eva Gonzalez-Suarez, Catalina Falo. First results of the randomized window of opportunity clinical trial D-Biomark: Immunomodulatory effect of denosumab in early breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-08-10.

Abstract CT191: A window-of-opportunity study with atezolizumab and the oncolytic virus pelareorep in early breast cancer (AWARE-1)

Background: A previous phase 2 study in metastatic breast cancer demonstrated a statistically significant improvement in overall survival (OS) in patients treated with pelareorep (pela), an intravenously delivered immuno-oncolytic reovirus, given in combination with paclitaxel (PTX) versus PTX alone [1]. We hypothesized that the OS benefit from pela + PTX may be attributed to an adaptive T cell response triggered by pela. To examine if pela can mediate the priming of an anti-tumor immune response, and the impact of checkpoint blockade therapy on this response, we and SOLTI research group are conducting the AWARE-1 study (NCT04102618) in patients with early breast cancer. The initial translational research results from this study are presented here. Methods: AWARE-1 is a window-of-opportunity study to evaluate the safety and effect of pela ± atezolizumab on the tumor microenvironment (TME) in 38 women with early breast cancer. Patients are treated with pela on days 1, 2, 8, and 9, and atezolizumab is administered on day 3. Tumor biopsies are collected at diagnosis, day 3, and day ~21. Five patient cohorts are being examined: Cohort 1: HR+/HER2-neg (10 patients) receiving pelareorep + letrozole (without atezolizumab); Cohort 2: HR+/HER2-neg (10 patients) receiving pelareorep + letrozole + atezolizumab; Cohort 3: TNBC (6 patients) receiving pelareorep + atezolizumab; Cohort 4: HR+/HER2+ (6 patients) receiving pelareorep + trastuzumab + atezolizumab; Cohort 5: HR-neg/HER+ (6 patients) receiving pelareorep + trastuzumab + atezolizumab. The primary endpoint is CelTIL score [2], a metric for quantifying changes in tumor cellularity and the number of tumor infiltrating lymphocytes (TILs), where an increase in CelTIL score has been associated with a favorable response to treatment. Tumor tissue is being examined for pela replication, changes to the TME by immunohistochemistry (IHC), PD-L1 expression by the Ventana SP142 assay used as the atezolizumab companion diagnostic, and T cell clonality by T cell receptor sequencing (TCR-seq). Peripheral blood is also being examined by TCR-seq. Results: Changes in the TME by IHC demonstrate that treatment with pela in the presence of atezolizumab increases the CD8/Treg ratio, a predictor of greater therapeutic efficacy, similar to preclinical breast cancer mouse models [3, 4]. Detailed TCR-seq, Ventana PD-L1 assay results, and IHC analysis will be presented, focusing on differences between patients receiving pela in the absence or presence of atezolizumab (Cohorts 1 and 2, respectively), and between CelTIL scores of responders and non-responders. Overall, these data demonstrate that pela can promote an inflamed tumor phenotype that allows for synergy with checkpoint blockade therapy in breast cancer.

References: [1] Bernstein, V., et al. Breast Cancer Res Treat, 2018. 167(2): p. 485-493. [2] Nuciforo, P., et al. Ann Oncol, 2018. 29(1): p. 170-177. [3] Mostafa, A.A., et al. Cancers (Basel), 2018. 10(6). [4] Lee, J., et al. Cancer Research, 2020. 80(16 Supplement): p. 2206-2206.

Citation Format: Luis Manso, Fernando Salvador, Patricia Villagrasa, Nuria Chic, Begoña Bermejo, Juan M. Cejalvo, Yann Izarzugaza, Blanca Cantos, Salvador Blanch, Mireia Margeli, Jose L. Alonso, Alejandro Martínez, Rafael Villanueva, Juan A. Guerra, Raquel Andrés, Pilar Zamora, Esteban Nogales, Manel Juan, Blanca Gonzalez-Farre, Grey A. Wilkinson, Thomas C. Heineman, Gerard Nuovo, Houra Loghmani, Matt Coffey, Azucena Gonzalez, Débora Martínez, Laia Paré, Tomás Pascual, Xavier Gonzalez, Aleix Prat, Joaquín Gavilá. A window-of-opportunity study with atezolizumab and the oncolytic virus pelareorep in early breast cancer (AWARE-1) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT191.

Abstract PS12-08: A window-of-opportunity study with atezolizumab and the oncolytic virus pelareorep in early breast cancer (REO-027, AWARE-1)

Background: A previous phase 2 study in metastatic breast cancer compared treatment with intravenously delivered oncolytic reovirus, pelareorep (pela), in combination with paclitaxel (PTX) versus PTX alone. This study demonstrated a statistically significant improvement in overall survival (OS), without differences in objective response or progression-free survival. We hypothesized that the OS benefit from pela + PTX may be attributed to an adaptive immune response triggered by pela. To test this hypothesis, and examine if pela can mediate the priming of an anti-tumor immune response, we designed a study called AWARE-1 (A window-of-opportunity study of pela in Early Breast Cancer), which is currently enrolling and for which initial translational research results are presented.

Methods: AWARE-1 is evaluating the safety and effect of pela ± atezolizumab on the tumor microenvironment (TME) in 38 women with early breast cancer. Patients are treated with pela on days 1, 2, 8, and 9, while atezolizumab is administered on day 3. Tumor biopsies are collected at diagnosis, day 3, and day ~21. Five cohorts will be examined: Cohort 1: Hormone Receptor-positive/HER2-negative (HR+/HER2-neg) (10 patients), pelareorep + letrozole. Cohort 2: HR+/HER2-neg (10 patients), pelareorep + letrozole + atezolizumab. Cohort 3: Triple Negative Breast Cancer (TNBC) (6 patients), pelareorep + atezolizumab. Cohort 4: Hormone Receptor-positive/HER2-positive (HR+/HER2+) (6 patients), pelareorep + trastuzumab + atezolizumab. Cohort 5: Hormone Receptor-negative/HER2-positive (HR-/HER2+) (6 patients), pelareorep + trastuzumab + atezolizumab. The primary endpoint of the study is CelTIL score, a metric for quantifying the changes in tumor cellularity and infiltration of TILs, where an increase in CelTIL is associated with a favorable response to treatment. Tumor tissue was examined for pela replication, and changes to the TME were assessed by imaging mass cytometry (IMC), immunohistochemistry, and T cell receptor sequencing (TCR-seq). Peripheral blood was also examined by TCR-seq.

Results: Detailed translational research results will be presented from patients in cohort 1, who received just pelareorep and letrozole. CelTIL score increased in 5/10 patients at day 3 biopsies and 6/10 patients at day 21 biopsies. Preliminary results show high levels of viral replication (&gt;50% of tumor cells) while immunohistochemistry and IMC analysis revealed changes to the TME, with increases in CD8+ T cells and upregulation of PD-L1 at both day 3 and day 21 biopsies. Overall, preliminary data from cohort 1 of AWARE-1 demonstrate pela-mediated priming of an adaptive immune response. (NCT04102618)

Citation Format: Luis Manso, Patricia Villagrasa, Nuria Chic, Begoña Bermejo, Juan Miguel Cejalvo, Yann Izarzugaza, Blanca Cantos, Salvador Blanch, Mireia Margeli, Jose Luis Alonso, Alejandro Martínez, Rafael Villanueva, Juan Antonio Guerra, Raquel Andrés, Pilar Zamora, Esteban Nogales, Manel Juan, Blanca González, Rita Laeufle, Gerard Nuovo, Grey Wilkinson, Matt Coffey, Azucena González, Débora Martínez, Laia Paré, Fernando Salvador, Xavier Gonzalez, Aleix Prat, Joaquín Gavilá. A window-of-opportunity study with atezolizumab and the oncolytic virus pelareorep in early breast cancer (REO-027, AWARE-1) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS12-08.

Abstract OT-26-04: Solti-1801. Analysis of the efficacy of CDK4/6 inhibitors in combination with hormonal treatment in luminal breast cancer in relation to the intrinsic subtype and markers of immunity (CDK-PREDICT)

Introduction. The incorporation of cyclin-dependent kinase inhibitors 4 and 6 (CDK4/6 inhibitors) with endocrine therapy in patients with advanced hormone receptor-positive (HR+) breast cancer and without overexpression of the HER2 (HER2-) oncogene has demonstrated its efficacy improving progression-free survival (PFS), overall response rate (ORR) and, more recently, overall survival (OS). However, patients eventually progress due to resistance to treatment. To date, no clinical or molecular markers defining the HR +/HER2- patient population that obtains the greatest benefit from these drugs have been found, apart from estrogen receptor positivity. However, there are data from multiple retrospective analysis suggesting that within HR+/ HER2- disease, the non-luminal intrinsic subtypes (20-30% of these patients) have a worse prognosis and may not benefit from CDK4/6 inhibitors. Furthermore, the prognostic impact of tumor infiltrating lymphocytes (TILs) and gene expression related to the immune response in the context of HR + / HER2- advanced breast cancer have not been deeply investigated.

Design. CDK-PREDICT is an observational, non-interventional, multicenter study that will include 114 patients with advanced breast cancer who have received, are receiving or are going to receive endocrine therapy plus a CDK4/6 inhibitor for, at least, 8 weeks as first-line treatment. The primary objective is to correlate the intrinsic subtypes (defined by PAM50) with the efficacy (measured as PFS) of CDK4/6 inhibitors + hormone therapy. As secondary objectives, the correlation of the intrinsic subtypes with ORR and with the histopathological characteristics of the tumor will be analyzed. In addition, the expression of immune response and cell cycle genes, as well as the presence of TILs, will be correlated with the intrinsic subtypes and with PFS and ORR. Overall, we aim to develop a predictive score combining clinical, genomic and immune expression data integrating tumor biology and microenvironment. For inclusion in the study, a metastatic sample taken within 90 days prior to CDK4/6 inhibitors treatment will be required. Once this sample has been collected, registered and assessed for quality, patients will be followed up every 6 months until disease progression, death or withdrawal from the study.

This project has received a research grant from “Instituto de Salud Carlos III (ISCIII), Ministerio de Economía y Competitividad” (Spain) awarded within the National Research Program with reference PI 18/01408, co-funded with European Union ERDF funds (European Regional Development Fund). This study is included within the Biomarker program of SOLTI. Recruitment of this study started in June 2020.

Citation Format: Pablo Tolosa, Tomás Pascual, Cristina Hernando, Sonia Servitja, María Fernández Abad, Rafael Villanueva, Fernando Henao, Javier Benítez, Laura Lema, Mario Martínez, Yolanda Ruano, Lucía Parrilla, Alejandra Bernardini, Ana María Roncero, Laia Paré, Jordi Canes, Fernando Salvador, Patricia Villagrasa, Aleix Prat, Eva Ciruelos. Solti-1801. Analysis of the efficacy of CDK4/6 inhibitors in combination with hormonal treatment in luminal breast cancer in relation to the intrinsic subtype and markers of immunity (CDK-PREDICT) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-26-04.

A phase Ib study to evaluate the oral selective estrogen receptor degrader GDC-9545 alone or combined with palbociclib in metastatic ER-positive HER2-negative breast cancer

1023

Background: GDC-9545 is a potent, orally available, selective estrogen receptor degrader developed for the treatment of ER-positive (ER+) breast cancer alone or combined with CDK4/6 inhibitors. A first-in-human study evaluated 10-250 mg GDC-9545; tolerability, pharmacokinetic (PK), pharmacodynamic (PD), and clinical results support expansion cohorts at ≥30 mg (Jhaveri et al., 2019). Methods: This study evaluated PK, PD, and efficacy of GDC-9545 alone and combined with palbociclib, ± LHRH agonist. Eligible patients (pts) had ER+ (HER2-) metastatic breast cancer (MBC) with ≤ 2 prior therapies in the advanced or metastatic setting. No prior treatment with CDK4/6 inhibitor was allowed in pts receiving palbociclib. Results: Eight-five pts were enrolled in 2 cohorts: GDC-9545 100 mg given once daily ± LHRH agonist (Cohort A), and GDC-9545 100 mg +125 mg palbociclib on a 21 day on/7 day off schedule ± LHRH agonist (Cohort B). Of the 39 pts in Cohort A, adverse events (AE) occurring in ≥10% of pts were fatigue, cough, back pain, pain in extremity, and arthralgia. Related AEs were generally Grade (G) 1-2; there were 3 related G3 AEs of fatigue, transaminase increased, and diarrhea. Two pts had GDC-9545 reduced, one due to G3 diarrhea and another due to G3 transaminitis. Of the 46 pts in Cohort B, AEs in ≥10% of pts were neutropenia, fatigue, bradycardia, diarrhea, constipation, dizziness, nausea, anemia, asthenia, thrombocytopenia, pruritus, and visual impairment. Twenty-six (57%) pts had G≥3 AEs. G≥3 neutropenia was reported in 23 (50%) pts. One pt had palbociclib reduced due to G3 febrile neutropenia. Eleven (13%) of 85 pts had G1 asymptomatic bradycardia considered related to GDC-9545. No pts in either cohort discontinued study treatment due to AEs. PK analysis and clinical data demonstrate no clinically relevant drug-drug interactions between GDC-9545 and palbociclib. Reduced ER, PR, and Ki67 levels, and an ER activity signature, were observed in paired pre- and on-treatment biopsies (n = 12). Eighteen of 33 pts in Cohort A had either confirmed partial responses or were on study 24 weeks (clinical benefit rate 55%). Clinical benefit was observed in pts with prior fulvestrant treatment and with detectable ESR1 mutations at enrollment. Clinical benefit data for both cohorts are anticipated to be mature in April 2020. Conclusions: GDC-9545 was well-tolerated as a single agent and in combination with palbociclib with encouraging PK, PD, and anti-tumor activity in ER+ MBC to support Phase III development. Clinical trial information: NCT03332797 .

Real-world efficacy and safety of eribulin in advanced and pretreated HER2-negative breast cancer in a Spanish comprehensive cancer center

Background

Eribulin improves survival in pre-treated HER2-negative advanced breast cancer (ABC). However, limited data exist on co-morbidities and central nervous system (CNS) efficacy. The purpose of this study was to review eribulin’s efficacy and safety in everyday clinical practice with special focus on age, body mass index (BMI) and central nervous system (CNS) activity.

Methods

An observational study was conducted in a series of HER2-negative ABC patients treated from January’14-December’17 outside a clinical trial. Objective Response Rate (ORR), Progression Free Survival (PFS), Overall Survival (OS), and association of clinical and pathological variables with outcome were evaluated.

Results

Ninety-five women were treated with at least one cycle of eribulin. Median age was 57 (33–83), and 18% were obese. Median number of prior chemotherapies for ABC was 3 (2–5) and 76% of patients had visceral metastases, including 21% with CNS involvement. Most tumors were estrogen receptor-positive (79%). ORR and stable disease (SD) at 6 months were 26.2 and 37.5%, respectively. Remarkably, relevant CNS efficacy was observed with eribulin: 20% of patients obtained partial response and 25% SD. Treatment was generally well tolerated and manageable, with 29% grade 3 and 10.9% grade 4 toxicities. Median PFS and OS were 4.1 months (CI95% 3.2–4.9) and 11.1 months (CI95% 9.5–14.7), respectively. Triple-negative disease, > 2organs involved and being younger than 70 years old were independent prognosis factors for worse OS in multivariate analysis. Most patients (75%) progressed in pre-existing metastases sites.

Conclusion

In everyday clinical practice, eribulin’s efficacy seems similar to pivotal trials. CNS-efficacy was observed. TNBC, > 2 organs involved and being younger than 70 years old were independent prognosis factors for worse OS. Remarkably, less incidence of grade 4-toxicity compared to previous studies was found.

Phase III MONALEESA-7 trial of premenopausal patients with HR+/HER2− advanced breast cancer (ABC) treated with endocrine therapy ± ribociclib: Overall survival (OS) results

LBA1008

Background: The phase III MONALEESA-7 study (NCT02278120) is the first dedicated trial of endocrine therapy (ET) ± a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor in premenopausal patients (pts) with hormone receptor–positive (HR+)/HER2− ABC. The study met its primary endpoint of significantly longer progression-free survival (PFS) with ribociclib (RIB; a CDK4/6 inhibitor) + ET vs placebo (PBO) + ET (median, 23.8 vs 13.0 mo; HR, 0.55; P < 0.0001; Tripathy D, et al. Lancet Oncol. 2018). Methods: Premenopausal pts (N=672) with HR+/HER2− ABC were treated with RIB or PBO + goserelin and either a nonsteroidal aromatase inhibitor (NSAI; letrozole or anastrozole) or tamoxifen. This is the 2nd of 3 protocol-specified OS analyses (scheduled to occur after ≈ 189 deaths [75% of the planned total events]). OS was evaluated by Kaplan-Meier methods, and statistical comparison was made by 1-sided stratified log-rank test, with a protocol-defined Lan-DeMets (O’Brien-Fleming) stopping boundary of p < 0.01018 for superior efficacy. Results: The data cutoff for this prespecified interim analysis was Nov 30, 2018, and the median follow-up was 34.6 mo (min, 28.0 mo). At cutoff, 173 pts were continuing study treatment (RIB, n=116; PBO, n=57), and OS was evaluated after 192 deaths (RIB, n=83; PBO, n=109). RIB + ET demonstrated a significantly longer OS than PBO + ET (median, not reached vs 40.9 mo [95% CI, 37.80 mo-not evaluable]; HR, 0.712 [95% CI, 0.54-0.95]; p = 0.00973). The result crossed the prespecified stopping boundary for superior efficacy. Estimated OS rates with RIB + ET vs PBO + ET at 42 mo were 70.2% vs 46.0%, respectively. In pts who received an NSAI (n=495), RIB + ET demonstrated a consistent OS improvement vs PBO + ET (HR, 0.699 [95% CI, 0.50-0.98]). Posttreatment therapy use was balanced between treatment arms (RIB, 68.9%; PBO, 73.2%). Conclusions: RIB + ET demonstrated a clinically and statistically significant longer OS than ET alone in premenopausal pts with HR+/HER2− ABC. This is the first time that a CDK4/6 inhibitor or any targeted agent + ET has demonstrated significantly longer OS vs ET alone as initial endocrine-based therapy. Clinical trial information: NCT02278120.

Palbociclib and ribociclib in breast cancer: consensus workshop on the management of concomitant medication

Drug–drug interactions are of significant concern in clinical practice in oncology, particularly in patients receiving Cyclin-dependent kinase (CDK) 4/6 inhibitors, which are typically exposed to long-term regimens. This article presents the highlights from the ‘First Workshop on Pharmacology and Management of CDK4/6 Inhibitors: Consensus about Concomitant Medications’. The article is structured into two modules. The educational module includes background information regarding drug metabolism, corrected QT (QTc) interval abnormalities, management of psychotropic drugs and a comprehensive review of selected adverse effects of palbociclib and ribociclib. The collaborative module presents the conclusions of the five working groups, each of which comprised five experts from different fields. From these conclusions positive lists of drugs for treating common comorbid conditions that can be safely administered concomitantly with palbociclib and/or ribociclib were developed.

The SASE1 X-ray beam transport system

SASE1 is the first beamline of the European XFEL that became operational in 2017. It consists of the SASE1 undulator system, the beam transport system, and the two scientific experiment stations: Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX), and Femtosecond X-ray Experiments (FXE). The beam transport system comprises mirrors to offset and guide the beam to the instruments and a set of X-ray optical components to align, manipulate and diagnose the beam. The SASE1 beam transport system is described here in its initial configuration, and results and experiences from the first year of user operation are reported.

Abstract P5-15-09: Impact of oncotype dx genetic signature used in early breast cancer. Clinical and economic analisys of a 110 patient cohort treated in the Catalan Oncologic Institute (ICO), Spain

Introduction

Benefit from adjuvant chemotherapy (CT) is doubtful in a high percentage of patients with early breast cancer. The 21-gene recurrence-score (RS) assay (Oncotype DX, Genomic Health) is one gene-expression assay that provide prognostic and predictive information in hormone-receptor (RH) positive breast cancer. The results of the TAILORx study have confirmed that the majority of patients with tumors RH + and HER2 negative can avoid CT without increasing their risk of relapse. From 2012 to 2015 we used Mammaprint (MMP), in our institution and 60% of cases could avoided CT (communicated in SABCS 2015). Since 2017 we use RS for this purpose.

Primary Objective

To analyze the impact of using RS to change the indication of adjuvant CT.

Secondary Objectives

To analyze the association between different clinical pathological factors and the RS value, and calculate the difference between the cost of all RS test and the cost in direct expense of the treatment with CT of all patients who could avoid it thanks to the RS

Material and methods

We analyzed all RS test performed in the three ICO centers during 2017. We sent 112 tumor samples; in 2 samples adequated RNA for RS was not obtained. We compared the adjuvant treatment initially planned according to institutional treatment protocol with the treatment given after RS. We compared the direct economic costs of CT with the costs of the diagnostic test, and performed a logistic regression analysis of some pathological factors and RS value.

Results

The RS could be determined in 110 of 112 cases, in which there was indication of adjuvant CT. Only 14 patients received CT (12,72%) with the RS value, so CT was avoided in 96 patients (87,28%).

The clinical-pathological characteristics of the series are summarized in the table 1. Of the risk factors analyzed, only grade 3 (p 0.001) and PR &lt;20% (p&lt;0.002) showed a statistically significant relationship with a higher probability of RS&gt; 25. No association was found between age, nodal status, tumor diameter, Ki67, Infiltrating Ductal Carcinoma vs neither Infiltrating Lobular Carcinoma nor Lympho-Vascular invasion.

The cost of the genetic studies was 180000€ (1636€ each). The cost of each CT schedule (EC x 4 followed by paclitaxel x 12) was 7214€ and the total cost of 96 cases 692590€. Direct costs savings estimated from the reduction in CT treatment were 512590€

Conclusion: Our series shows that RS avoided unnecessary CT in 87% of cases and was more cost-effective than a previous series with MMP. G3 and RP &lt;20 were the only pathological factors associated with an increased risk of RS&gt; 25.

Table 1.Patients characteristics and clinical-pathological details from the analyzed tumorsPatient characteristicsAge, mean (range)53,76 (19 – 75)≥50y72 (65.5%)&lt;50y38 (34.5%)HistologyInfiltrating ductal carcinoma88 (80%)Infiltrating lobular carcinoma20 (18,2%)Others2 (1,8%)TNMTumor diameter (mm), mean (range)19,25 (1 – 160)pN058 (52,7%)pN1mic21 (19%)pN131 (28,3%)Hormone receptorsRE 2-100%110 (100%)RP &lt;20%22 (20%)RP ≥20%88 (80%)Ki67 median, mean (range)20, 21 (2-75)Lymphovascular invasionyes9 (8%)no101 (92%)Adjuvant treatmentCT14 (12,72%)Hormonotherapy96 (87,28%)

Citation Format: Ferrer M, Dorcas J, Quiroga V, Margelí M, del Barco S, Stradella A, Petit A, Falo C, Viñas G, Romeo M, Villanueva R, Cirauqui B, Vázquez S, Fernández A, Recalde S, Vethencourt A, Soler T, Pérez-Martín X, Gil-Gil M. Impact of oncotype dx genetic signature used in early breast cancer. Clinical and economic analisys of a 110 patient cohort treated in the Catalan Oncologic Institute (ICO), Spain [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-15-09.

Abstract PD5-10: A first-in-human phase I study to evaluate the oral selective estrogen receptor degrader (SERD), GDC-0927, in postmenopausal women with estrogen receptor positive (ER+) HER2-negative metastatic breast cancer (BC)

Background: Modulation of estrogen activity and/or synthesis is the mainstay therapeutic strategy in the treatment of ER+ BC. However, despite the effectiveness of available endocrine therapies, many patients ultimately relapse or develop resistance to these agents via estrogen-dependent and estrogen-independent mechanisms, including mutations in ESR1 affecting the ER ligand binding domain that drive ER-dependent transcription and proliferation in the absence of estrogen. ER antagonists that are efficacious against ligand-dependent and ligand-independent, constitutively active ESR1 mutant tumors may be of substantial therapeutic benefit. GDC-0927 (formerly known as SRN-927) is a novel, potent, non-steroidal, orally bioavailable, selective ER antagonist/ER degrader (SERD) that induces tumor regression in ER+ BC patient-derived xenograft models.

Methods: A phase I dose escalation study with 3+3 design was conductedin postmenopausal women with ER+ (HER2-) metastatic BC (progressing ≥ 6 months on endocrine therapy and with ≤ 2 prior chemotherapies in the advanced or metastatic setting) to determine the safety, pharmacokinetics (PK) and the recommended Phase 2 dose (RP2D) of GDC-0927. Pharmacodynamic (PD) activity was assessed with [18F]-fluoroestradiol (FES)-PET scans. Plasma PK samples (after single dose and at steady state), CT scans, and when feasible, pre and on-study tumor biopsies were obtained

Results: From March 16, 2015 to March 17, 2017 patients (pts) with a median age of 53 years (range 44-69) and a median number of prior therapies for MBC 4 (range 1-7) were enrolled at 3 total daily dose levels (600, 1000, 1400 mg) once daily (QD) given orally with fasting (n = 12). Increases in GDC-0927 exposure were approximately dose proportional. Treatment related adverse events (AEs) were all grade 1 or 2. The most common treatment-related AEs were nausea (54%, n = 7), diarrhea (46%, n = 6), elevated aspartate aminotransferase (39%, n = 5) and anemia, constipation, (each 31%, n = 4). Treatment interruption was required for 2 pts due to nausea and vomiting. Of those pts with FES-PET avid disease at baseline (9 of 12), all post-therapy scans showed complete or near complete (&gt; 90%) suppression of FES uptake to background levels, including pts with ESR1 mutations. Evidence of reduced ER levels and Ki67 staining was observed in on-treatment biopsies. Five of 12 pts (1 at 600 mg and 4 at 1400 mg) were on study ≥ 24 weeks (CBR = 41.6 %) with the best overall response of stable disease with 1 patient (ESR1 mt+ D538G) on study for over 490 days. There were no dose limiting toxicities and no SAEs related to study drug. R2PD was 1400 mg and was selected for single arm dose-expansion which is now complete with last patient enrolled on March 17, 2017. Updated results from dose-escalation and dose-expansion will be presented at the meeting (N = 43).

Conclusions: GDC-0927 appears well-tolerated to date with PK exposure supporting QD dosing, evidence of robust PD target engagement, and encouraging anti-tumor activity in heavily pretreated pts with advanced or metastatic ER+ BC, including pts with ESR1 mutations.

Citation Format: Dickler MN, Villanueva R, Perez Fidalgo JA, Mayer IA, Boni V, Winer EP, Hamilton EP, Bellet M, Urruticoechea A, Gonzalez-Martin A, Cortes J, Martin M, Giltnane J, Gates M, Cheeti S, Fredrickson J, Wang X, Friedman LS, Spoerke JM, Metcalfe C, Liu L, Li R, Morley R, McCurry U, Chan IT, Mueller L, Milan S, Lauchle J, Humke EW, Bardia A. A first-in-human phase I study to evaluate the oral selective estrogen receptor degrader (SERD), GDC-0927, in postmenopausal women with estrogen receptor positive (ER+) HER2-negative metastatic breast cancer (BC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD5-10.

Measuring the condylar unit in condylar hyperplasia: from the sigmoid notch or from the mandibular lingula?

The objective of this study was to determine, in patients with active unilateral condylar hyperplasia, which is the most reliable point to measure the length of the condylar unit: from the sigmoid notch or from the mandibular lingula to the condylar head. On cone beam computed tomography, an observational cross-sectional study was designed for 20 patients with active unilateral condylar hyperplasia. We measured and compared ramus length (affected and healthy sides) and condylar length (measured from the mandibular lingula and from the mandibular sigmoid notch) on both sides. The average of all the differences in ramus height (D.1) was 7.97mm; the average of all the differences in condylar heights measured from mandibular lingula (D.2) was 7.16mm, and measured from the sigmoid notch (D.3) was 4.89mm. No significant difference between D.1 and D.2 (P=0.818). There was a significant difference between D.1 and D.3 (P=0.005) and between D.2 and D.3 (P=0.0005). It can be concluded that the mandibular lingula is the lowest point of the condylar skeletal unit and is therefore a stable parameter to be used in patients with condylar hyperplasia. On the other hand, the sigmoidal notch is not a stable parameter in patients with asymmetry due to condylar hyperplasia.

Mindfulness effects on cognition: Preliminary results

Background

Mindfulness-based cognitive therapy (MBCT) is a psychotherapeutic intervention that has been shown effective in several clinical conditions. Nevertheless, research is still needed on its effectiveness on cognition.

Objective

To analyze possible effects on cognition of the addition of MBCT intervention versus a brief structured group psycho-education to the standard treatment of subsyndromal bipolar depression. Our hypothesis was that MBCT could improve some aspects of cognitive function to a higher degree than psycho-education and treatment as usual (TAU).

Methods/design

A randomized, multicenter, prospective, versus active comparator, evaluator-blinded clinical trial was conducted. Forty patients with BD and subclinical or mild depressive symptoms were randomly allocated to:

– MBCT added to psychopharmacological treatment (n = 16);

– a brief structured group psycho-educational intervention added to psychopharmacological treatment (n = 17);

– standard clinical management, including psychopharmacological treatment (n = 7).

Assessments were conducted at screening, baseline, post-intervention (8 weeks) and 4-month follow-up.

Results

Cognition results point to significant improvement in Stroop Color test as well as processing speed in TMT A test (P < 0.05) in the two psychological intervention groups versus TAU.

Conclusion

These preliminary findings suggest that the addition of MBCT or psycho-education to usual treatment could improve some cognitive dimensions in subsyndromal bipolar depressive patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Abstract P4-21-32: Treatment of early HER2-positive breast cancer in trastuzumab era in everyday clinical practice: An overview after 10 years of its approval

Introduction: The addition of Trastuzumab(T) to chemotherapy (CT) revolutionized HER2-positive breast cancer(BC) and changed its natural history. We reviewed the efficacy of T outside clinical trials in a cancer comprehensive center.

Methods: Ambiespective and descriptive study was conducted in Catalan Institute of Oncology (ICO-Barcelona). Estimates of progression-free survival (PFS) and overall survival (OS) were obtained with the Kaplan-Meier method and compared with LogRank test. The association of clinic-pathological variables and outcome was studied by χ2and Cox proportional hazard analysis.

Results: 430 consecutive early HER2-positive BC patients (pts) were treated with adjuvant/neoadjuvant T and CT from Jan 2005 to Dec 2012. Pt basal characteristics are reported in Table 1. Neoadjuvant treatment was administrated in 230pts (54%) and in 200 (46%) in adjuvancy. Pathological complete response (pCR) in breast and nodes (ypT0/isypN0) was achieved in 48% of pts, with higher rates in hormone receptor (HR)-negative pts (62 vs 37% p=0.0005). Median duration of T: 10.6 months (m). 28%pts treated with neoadjuvant T+CT who achieved a pCR did not receive adjuvant T. Treatment discontinuation: 38pts (8.8%): 27pts due to cardiac toxicity and 4 relapsed during adjuvant T. In 87%pts, neoadjuvant CT was based on anthracyclines(A) and taxanes. Adjuvant CT: A and taxanes in 57.4%; 14%pts FAC, 15.4% A-CMF and 12% TCH. At a median follow-up of 70m (3-135), 44pts (10.4%) had relapsed: 33pts with distant M1, 9pts with only loco-regional disease and 2pts contralateral HER2-positive BC. M1 location: 46% visceral, 34% bone/lymph nodes and 20% in central nervous system (CNS). PFS was 23.4m(0-88); median OS was not reached; estimated 10 years-OS was 86.5%. Pts treated with A and taxanes had a significantly better OS compared to those treated with other CT (113 vs 98m, p= 0.009). Kaplan-Meier curve showed numerically higher relapses at 10 years in HR-positive pts (83 vs 90% p=0.8). Pts with pCR had significantly better OS (113 vs 104m, p=0.006). Pts with CNS-metastases had a significantly worse OS (13 vs 26m,p=0,02) and those with HR-negative (49 vs 24m, p= 0.033).

Conclusion: In everyday clinical practice, recurrences after adjuvant/neoadjuvant trastuzumab in HER2-positive BC were less than described in the T-pivotals trials, with 10% of recurrences at a median of FU of 70m. In our series, estimated 10 years-OS was 86.5%. Pts treated with A and taxanes had a significantly better OS as well as those pts who achieved a pCR. On the contrary, pts with CNS M1 and those with HR-negative had worse prognosis.

Table 1Median age51.9y (27-83)Stage I/II/III106 (25%)/ 226 (52%)/ 97 (23%)HR Positive/ Negative249 (58%)/181 (42%)

Citation Format: Ortega A, Domenech M, Falo C, Gil M, Stradella A, Fernandez A, Morilla I, Villanueva R, Castany R, Vazquez S, Molina K, Bergamino M, Navarro V, Pernas S. Treatment of early HER2-positive breast cancer in trastuzumab era in everyday clinical practice: An overview after 10 years of its approval [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-32.

Failure pattern after response to reversible tyrosine kinase inhibitors in advanced non-small cell lung cancer

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Background: Reversible tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) significantly increase survival for patients with previously treated advanced non-small cell lung cancer (NSCLC). Some studies have shown that most of responders to TKIs failed due to the appearance of new lesions without progression of the pre-existing target lesions. Methods: We retrospectively reviewed patients with advanced NSCLC diagnosed from 2005 to 2010 at two different hospitals in Catalonia (Spain) to identify those treated with TKIs. Patients with a clinical objective benefit as defined by Jackman were included. We analyzed both the clinical features of patients and their failure pattern. Results: There were 34 patients, 14 were women, with a median age of 64 years (range: 38 -81 years). Twenty-seven cases were adenocarcinoma while only 3 were squamous cell carcinoma. Eleven patients had never smoked. Previously to TKI, all patients received at least one line of chemotherapy except nine patients who received TKI as first-line treatment. Median time to progression after initiation of TKI was 8.7 months (1.9 - 38.9 months). Radiological TKI response was CR/PR/SD: 1/15/17 (1 not available). Rash and diarrhea were the most common toxic effects. No grade 3 or 4 toxicities were observed. TKI was discontinued in all patients after disease progression; 12 patients were unable to receive further therapy due to symptomatic deterioration. In 19 patients, PD was due to the appearance of new lesions and not to progression of the pre-existing lesions. Results of mutations of EGFR were available in 7 patients (ratio of mutant/wild status was 5/2). In all patients with known EGFR mutation, only new lesions leaded to progression. Conclusions: In spite of our series’ heterogeneity, results are consistent with previous data and suggest that a wide range of patients can benefit from TKIs. Furthermore, more than half of progressions were due to new lesions. Patients with known EGFR mutation strictly followed this failure pattern, though larger studies in EGFR mutated patients are needed to assess both failure patterns and benefits of continuing TKIs after progression when pre-existing lesions are stable.

Visualization and 3D reconstruction of flame cells of Taenia solium (cestoda)

Background

Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function.

Methodology/Principal Findings

Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells.

Conclusions/Significance

We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton.

Decision Support Alerts for Medication Ordering in a Computerized Provider Order Entry (CPOE) System: A systematic approach to decrease alerts

OBJECTIVE

We sought to determine the frequency and type of decision support alerts by location and ordering provider role during Computerized Provider Order Entry (CPOE) medication ordering. Using these data we adjusted the decision support tools to reduce the number of alerts.

DESIGN

Retrospective analyses were performed of dose range checks (DRC), drug-drug interaction and drug-allergy alerts from our electronic medical record. During seven sampling periods (each two weeks long) between April 2006 and October 2008 all alerts in these categories were analyzed. Another audit was performed of all DRC alerts by ordering provider role from November 2008 through January 2009. Medication ordering error counts were obtained from a voluntary error reporting system. MEASUREMENTRESULTS: Between April 2006 and October 2008 the percent of medication orders that triggered a dose range alert decreased from 23.9% to 7.4%. The relative risk (RR) for getting an alert was higher at the start of the interventions versus later (RR= 2.40, 95% CI 2.28-2.52; p< 0.0001). The percentage of medication orders that triggered alerts for drug-drug interactions also decreased from 13.5% to 4.8%. The RR for getting a drug interaction alert at the start was 1.63, 95% CI 1.60-1.66; p< 0.0001. Alerts decreased in all clinical areas without an increase in reported medication errors.

CONCLUSION

We reduced the quantity of decision support alerts in CPOE using a systematic approach without an increase in reported medication errors.

Human gamma-aminobutyric acid A receptor alpha2 gene moderates the acute effects of alcohol and brain mRNA expression

Gamma-aminobutyric acid A (GABA(A)) receptors moderate several of the behavioral effects of alcohol. In fact, recent studies have shown an association between the gene for the alpha2-subunit of the GABA(A) receptor (GABRA2) and alcoholism. In the present study, we examined the functional relevance of the GABRA2 gene in alcohol dependence by assessing brain GABRA2 mRNA and GABA(A)alpha2-subunit protein levels in post-mortem prefrontal cortical tissue collected from control and alcohol-dependent individuals. In addition, using an endophenotype approach, we tested whether the GABRA2 gene moderates sensitivity to the acute effects of alcohol in two independent samples from distinct human alcohol challenge studies. Results indicated that GABRA2 mRNA levels significantly differed by GABRA2 genotype. GABRA2 single nucleotide polymorphisms (rs573400, rs279871 and rs279858) were significantly associated with sensitivity to the acute effects of alcohol. Specifically, there was a significant main effect of GABRA2 x breath alcohol concentration on several measures of subjective responses to alcohol, including the hedonic value of alcohol. Importantly, reanalysis of a previous intravenous alcohol administration study confirmed the results of the oral alcohol challenge study. In summary, these results extend previous findings and provide new insights into the putative biobehavioral mechanisms that may moderate the association between the GABRA2 gene, sensitivity to the acute effects of alcohol and ultimately alcohol dependence.

[In vitro activity of ertapenem against clinical bacterial isolates in 69 Spanish medical centers (E-test study)]

This study was conducted to assess the in vitro activity of ertapenem against clinical bacterial isolates from patients with community-acquired intra-abdominal and lower tract respiratory infections in Spain in 2003. As the study was conducted before the marketing of ertapenem, it was also useful to define a baseline susceptibility pattern for ertapenem in each of the participating hospitals for later surveillance studies. Each partipating site identified a variable number of aerobic and facultative bacteria isolated from patients with community-acquired intra-abdominal infection or pneumonia using standard procedures. E-test strips were used for determining the minimum inhibitory concentration (MIC) of ertapenem, while for other antimicrobials either quantitative dilution techniques or qualitative diffusion procedures were used according to each microbiology laboratory's routine practice. MIC breakpoints for categorization of susceptibility provided by the CLSI were used for interpreting MIC values. A total of 2,901 recent clinical isolates from patients with community-acquired intra-abdominal infection or pneumonia hospitalized in 69 Spanish medical centers were tested. These isolates included 2,039 Gram-negative bacteria (1,646 Enterobacteriaceae, 216 Haemophilus, 123 non-fermenting Gram-negative bacteria [NFGNB] and 54 others) and 862 Gram-positive bacteria (556 pneumococci, 159 staphylococci, 96 streptococci other than S. pneumoniae, 44 enterococci and 7 others). Ertapenem was very active in vitro against Enterobacteriaceae (99.8% susceptible), Haemophilus (96.3% susceptible), pneumococci (99.6% susceptible, of which 31% were penicillin non-susceptible strains), streptococci other than S. pneumoniae (99.0% susceptible) and methicillin-susceptible staphylococci (94.8% susceptible). For other Gram-positive and Gram-negative pathogens for which ertapenem susceptible breakpoints have not been defined, MIC(90) values were 0.38 and 0.064 mg/l, respectively. As expected, ertapenem had minimal activity in vitro against NFGNB, enterococci and methicillin-resistant staphylococci (MIC(90) of >32 mg/l for all three). Ertapenem was highly active in vitro against most bacteria isolated from patients with community-acquired intra-abdominal and lower respiratory tract infections.

Association of polymorphisms in myeloperoxidase and catalase genes with precancerous changes in the gastric mucosa of patients at inner-city hospitals in New York

Gastric carcinogenesis is a multistep process progressing from chronic gastritis, through glandular atrophy (GA), intestinal metaplasia (IM) and dysplasia. We have previously demonstrated that minority patients at New York City hospitals are infected with a relatively virulent strain of H. pylori (Hp) and that Hp infection is associated with an increased incidence of precancerous changes in the gastric mucosa. Nevertheless, precancerous changes are not observed in every Hp-infected individual, suggesting that environmental and genetic factors may also play a role in the formation and appearance of precancerous lesions. In the present study, the association between polymorphisms in the promoter regions of human myeloperoxidase (MPO -463G--> A) and catalase (CAT -262C-->T) genes and the appearance of precancerous changes in the gastric mucosa of our patient population were examined. Patients enrolled in this study were undergoing endoscopy for gastrointestinal complaints. Samples were collected from 126 patients at Kings County Hospital in Brooklyn and St. John's Episcopal Hospital in Queens. One antral biopsy was taken for genotyping, while additional biopsies were taken from the antrum and fundic region for histological analysis and were scored with respect to acute and chronic inflammation, GA, IM and Hp infestation according to the Sydney classification. MPO and CAT genotypes were determined by PCR and RFLP. CAT genotypes did not influence the incidence or severity of precancerous lesions in the fundic or antral regions of the stomach, whereas the MPO -463A allele was associated with an increase in intensity of gastric atrophy in the fundic mucosa. In Hp-infected individuals, the MPO -463G/G genotype was associated with an increase in the incidence of IM in the antrum, whereas the A allele was associated with an increase in IM in the fundic region. These paradoxical findings suggest that different MPO genotypes are associated with the appearance of IM in distinct anatomical regions of the stomach. However, since the majority of gastric cancer (GC) cases in our patient population occurred in the antrum, the MPO -463G/G genotype, which is associated with increased MPO expression and antral IM, may be considered a risk factor for GC.

Helicobacter pylori infection is associated with a high incidence of intestinal metaplasia in the gastric mucosa of patients at inner-city hospitals in New York

Gastric carcinogenesis is a multistep process progressing from chronic gastritis, through glandular atrophy (GA), intestinal metaplasia (IM) and dysplasia. Infection of the stomach with H. pylori increases the risk of developing gastric cancer. Few studies have examined the degree to which Hp-induced changes occur in specific populations. In the present study, we examined the association between Hp infection and histological changes in the gastric mucosa of patients at two inner-city hospitals in New York. Patients enrolled in this study were undergoing endoscopy for gastrointestinal complaints. One antral biopsy was taken for detecting and genotyping Hp by PCR. Additional biopsies were taken from the antrum and fundic region for histological analysis and were scored with respect to acute and chronic inflammation, GA, IM and Hp infestation according to the Sydney classification. Hp strains infecting these patients were genotyped with respect to the expression of Hp virulence factors including VacA, CagA, and BabA2. Samples were collected from 126 patients at Kings County Hospital in Brooklyn and St. John's Episcopal Hospital in Queens. Hp infection rates were highest in Blacks (41.6%) and Hispanics (29.4%) and lowest in Caucasians (18.8%). Scores for acute and chronic inflammation and IM were higher in Hp-infected individuals in both the antrum and fundic regions, whereas Hp infection did not affect the incidence or intensity of GA. In Hp-infected individuals, the incidence of IM was greater in the antrum (Hp-infected 37.8% vs. non-infected 9.2%, p < 0.05) and fundic region (Hp-infected 15.1% vs. noninfected 1.8%, p < 0.05). Genotyping of the Hp strains infecting these patients revealed that the predominant VacA allele was s1 bm 1 and that the CagA gene was present in 69.8% of Hp-infected samples. Interestingly, the BabA2 gene was detected in only four samples (9.3%). The incidence of IM in the antrum was higher in CagA + samples when compared with CagA- samples (52.2% vs. 15.4%, respectively). Our findings indicate that the virulent Hp strain infecting minority patients treated at inner-city hospitals in New York City is associated with a high incidence of IM and that these patients may be at greater risk for developing gastric cancer than the general population.

Clinical prognostic factors in metastatic gastrointestinal stromal tumors (GIST) patients treated with Imatinib

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Background: Imatinib (IMT) therapy is the main successful therapy for metastatic GIST. We analyze the results of the treatment according to the clinical factors and dose of IMT. Methods: 38 patients (pts) with metastatic GIST (C-KIT positive) were treated from June 2001 to June 2005 with IMT; 11 pts received 400 mg bid and 27 pts 400 mg daily. Evaluation of c-Kit mutation on exon 11 was analyzed in 23 pts. An analysis of the clinical factors was performed. Results: The average age was 60 y. (18–78); Gender: 26 male/12 female; Primary location in small bowel 24, gastric 12, esophagus 2. ECOG 0–1 in 87% of pts. 31 pts have had radical surgery at the primary (26 R0, 5 R1). Interval to metastatic/local relapse was 10 months (2–61). Hepatic metastases were presented in 26 pts (1–5 in 12, 6–10 in 5, >10 in 9 pts); peritoneal disease in 26 pts (1–5 in 10, 6–10 in 8, >10 in 7 pts); pulmonary metastases in 2, bone in 2 and nodal in 3 pts; local tumor in 6. With a median follow-up of the 56 m, response rate was 5 complete, 21 partial responders, 7 disease stabilization. Three pts died in the first month of treatment, two due to tumoral bleeding, one due to progressive disease. Median survival (MS) was 43 (0–54) months, not achieved for pts in 400 mg, 41 months for 400 mg bid pts (p=0.61). Progression free survival (PFS) was 21 months (21 for pts in 400 mg, 20 for pts in 400 mg bid). We don’t find statistical differences regarding the number of hepatic and peritoneal metastases, neither according to the size of metastases (<10 cm was 48 m., ≥10 cm was 41 m.). MS was not achieved in 18/23 patients with exon 11 mutation vs 9 months for non-mutation patients (p 0.00). No differences were found in survival for 4/18 pts with missense mutation. Conclusions: Mutational status may predict the outcome of GIST patients treated with IMT. Dose of IMT, mass size and number of metastases were not prognostic factors for survival. Special attention would be done to the risk of bleeding at the start of treatment with IMT.

No significant financial relationships to disclose.

Characterisation of the first CTX-M-10-producing isolate of Salmonella enterica serotype Virchow

Microbiological analysis of a urine sample from an outpatient with symptoms of urinary infection detected >10(5) CFU/mL urine of Salmonella enterica serotype Virchow with resistance to cefotaxime. Molecular analysis demonstrated the presence of the gene encoding CTX-M-10 beta-lactamase in this clinical isolate. This is the first report of this enzyme in Salmonella spp.

Evaluation of Group B Streptococcus Differential Agar for detection and isolation of Streptococcus agalactiae

In total, 320 vaginal or rectal swabs were cultured on Granada medium (GM) or Group B Streptococcus Differential Agar (GBSDA), and were also inoculated into LIM broth (Todd-Hewitt broth supplemented with selective antibiotics), for detection of group B Streptococcus (GBS). Overall, GBS isolates were detected on 53 of the 320 swabs; 47 of these isolates grew on both GM and GBSDA, five only on GBSDA, and one only following subculture from LIM broth. GBSDA appears to be a valid alternative to GM for the growth of GBS isolates from pregnant women.

Hospital outbreak caused by a carbapenem-resistant strain of Acinetobacter baumannii: patient prognosis and risk-factors for colonisation and infection

Between October 2001 and August 2002, 30 hospital patients became infected or colonised by a multiresistant (including to carbapenems) epidemic strain of Acinetobacter baumannii (AbMR) in a hospital outbreak. This study analysed the risk-factors associated with acquisition of this epidemic strain and investigated the prognosis of patients infected by AbMR, with the aim of elucidating factors which lead to mortality. A case-control study of the acquisition of AbMR in patients infected or colonised in the hospital outbreak was performed. Independent risk-factors leading to death were studied by logistic regression analysis. Multivariate analysis of the risk-factors for colonisation/infection with AbMR revealed an independent association with the presence of an arterial catheter (OR, 1.13; 95% CI, 1.03-1.25) and administration of imipenem as monotherapy (OR, 11.12; 95% CI, 2.33-53.09). Multivariate analysis of the prognostic features leading to mortality revealed a significant association with hypotension or shock (OR, 24.63; 95% CI, 1.56-387.56) at the time of bacterial isolation.

Sibling recurrence risk in autoimmune thyroid disease

There is abundant evidence for a genetic influence on the development of autoimmune thyroid diseases (AITD). One measure of the magnitude of genetic contribution to the development of a disease is the sibling risk ratio (lambda(s)). Recent accurate prevalence data for hypothyroidism and hyperthyroidism in the United States reported from the National Health and Nutrition Examination Survey III (NHANES III) study have now allowed us to compute the sibling recurrence risk for AITD. Patients were recruited from our endocrine clinic on the basis of having AITD. The inclusion of patients in this study was unambiguously single ascertainment. We studied 155 patients (131 with Graves' disease [GD] and 24 with Hashimoto's thyroiditis [HT]) who had reliable information on the presence or absence of AITD in siblings. Nine probands had siblings with GD and 13 probands had siblings with HT. Using the prevalence rates from NHANES III for clinical hyperthyroidism and hypothyroidism, the calculated lambda(s) was 16.9 for AITD, 11.6 for GD, and 28.0 for HT. These results confirm the significant contribution of genetic factors to the development of AITD.

A new report of mesomelic camptomelia, polydactyly and Dandy-Walker complex in siblings

Two male siblings with several malformations are reported. The anomalies detected in both fetuses were mesomelic camptomelia, postaxial hexadactyly and Dandy-Walker complex. There was only one similar previous report in the literature. This combination could represent a specific pattern of malformation or a new syndrome, with different variants. The parents' consanguinity and the recurrence in a subsequent pregnancy suggest an autosomal recessive inheritance pattern.