Tumor-agnostic baskets to N-of-1 platform trials and real-world data: Transforming precision oncology clinical trial design

Choosing the right drug(s) for the right patient via advanced genomic sequencing and multi-omic interrogation is the sine qua non of precision cancer medicine. Traditional cancer clinical trial designs follow well-defined protocols to evaluate the efficacy of new therapies in patient groups, usually identified by their histology/tissue of origin of their malignancy. In contrast, precision medicine seeks to optimize benefit in individual patients, i.e., to define who benefits rather than determine whether the overall group benefits. Since cancer is a disease driven by molecular alterations, innovative trial designs, including biomarker-defined tumor-agnostic basket trials, are driving ground-breaking regulatory approvals and deployment of gene- and immune-targeted drugs. Molecular interrogation further reveals the disruptive reality that advanced cancers are extraordinarily complex and individually distinct. Therefore, optimized treatment often requires drug combinations and N-of-1 customization, addressed by a new generation of N-of-1 trials. Real-world data and structured master registry trials are also providing massive datasets that are further fueling a transformation in oncology. Finally, machine learning is facilitating rapid discovery, and it is plausible that high-throughput computing, in silico modeling, and 3-dimensional printing may be exploitable in the near future to discover and design customized drugs in real time.

CONTACT-01: A Randomized Phase III Trial of Atezolizumab + Cabozantinib Versus Docetaxel for Metastatic Non-Small Cell Lung Cancer After a Checkpoint Inhibitor and Chemotherapy

PURPOSE

Although checkpoint inhibitors have improved first-line treatment for non-small cell lung cancer (NSCLC), a therapeutic need remains for patients whose disease does not respond or who experience disease progression after anti-PD-L1/PD-1 immunotherapy. CONTACT-01 (ClinicalTrials.gov identifier: NCT04471428) evaluated atezolizumab plus cabozantinib versus docetaxel in patients with metastatic NSCLC who developed disease progression after concurrent or sequential treatment with anti-PD-L1/PD-1 and platinum-containing chemotherapy.

METHODS

This multicenter, open-label, phase III trial randomly assigned patients 1:1 to atezolizumab 1,200 mg intravenously once every 3 weeks (q3w) plus cabozantinib 40 mg orally once daily or docetaxel 75 mg/m2 intravenously once every 3 weeks. The primary end point was overall survival (OS).

RESULTS

One hundred eighty-six patients were assigned atezolizumab plus cabozantinib, and 180 docetaxel. Minimum OS follow-up was 10.9 months. Median OS was 10.7 months (95% CI, 8.8 to 12.3) with atezolizumab plus cabozantinib and 10.5 months (95% CI, 8.6 to 13.0) with docetaxel (stratified hazard ratio [HR], 0.88 [95% CI, 0.68 to 1.16]; P = .3668). Median progression-free survival was 4.6 months (95% CI, 4.1 to 5.6) and 4.0 months (95% CI, 3.1 to 4.4), respectively (stratified HR, 0.74 [95% CI, 0.59 to 0.92]). Serious adverse events (AEs) occurred in 71 (38.4%) patients receiving atezolizumab plus cabozantinib and 58 (34.7%) receiving docetaxel. Grade 3/4 treatment-related AEs occurred in 73 (39.5%) patients receiving atezolizumab plus cabozantinib and 58 (34.7%) receiving docetaxel. Grade 5 AEs occurred in 14 (7.6%) and 10 (6.0%) patients in the atezolizumab plus cabozantinib and docetaxel arms, respectively (treatment-related in four [2.2%] and one [0.6%], respectively).

CONCLUSION

Atezolizumab plus cabozantinib after disease progression following anti-PD-L1/PD-1 immunotherapy and platinum-containing chemotherapy for metastatic NSCLC did not improve OS compared with docetaxel. Safety was consistent with known profiles of these agents.

Microsatellite Instability Is Insufficiently Used as a Biomarker for Lynch Syndrome Testing in Clinical Practice

PURPOSE

The pan-cancer presence of microsatellite instability (MSI)-positive tumors demonstrates its clinical utility as an agnostic biomarker for identifying immunotherapy-eligible patients. Additionally, MSI is a hallmark of Lynch syndrome (LS), the most prevalent cancer susceptibility syndrome among patients with colorectal and endometrial cancer. Therefore, MSI-high results should inform germline genetic testing for cancer-predisposing genes. However, in clinical practice, such analysis is frequently disregarded.

METHODS

A next-generation sequencing (NGS)-based technique was used for MSI analysis in 4,553 patients with various tumor types. Upon request, somatic BRAF gene analysis was conducted. In addition, hereditary testing of cancer-associated genes was performed in MSI-high cases using a capture-based NGS protocol. MLH1 promoter methylation analysis was conducted retrospectively in patients with colorectal and endometrial cancer to further investigate the origin of MSI at the tumor level.

RESULTS

The MSI positivity rate for the entire cohort was 5.27%. Endometrial, gastric, colorectal, urinary tract, and prostate cancers showed the highest proportion of MSI-high cases (15.69%, 8.54%, 7.40%, 4.55%, and 3.19%, respectively). A minority of 45 patients (22.73%) among the MSI-high cases underwent germline testing to determine whether the mismatch repair pathway deficiency was inherited. 24.44% of those who performed the genetic test carried a pathogenic variant in an LS-associated gene. Three MSI-high individuals had non-LS gene alterations, including BRCA1, BRCA2, and CDKN2A pathogenic variants, indicating the presence of non-LS-associated gene alterations among MSI-high patients.

CONCLUSION

Although MSI analysis is routinely performed in clinical practice, as many as 77% of MSI-high patients do not undergo LS genetic testing, despite international guidelines strongly recommending it. BRAF and MLH1 methylation analysis could shed light on the somatic origin of MSI in 42.50% of the MSI-high patients; however, MLH1 analysis is barely ever requested in clinical practice.

Dataset of phase I and II immunotherapy clinical trials used for a meta-analysis to assess the role of biomarkers in treatment outcomes in diverse cancers

We performed a literature search in PubMed to identify phase I/II clinical trials with immunotherapy drugs approved by the Food and Drug Administration (labeled, off-label, and/or combined with investigational immune checkpoint inhibitors or other treatment modalities) from 2018 to 2020. We used the following key words: clinical trials, phase 1, Phase 2; and the following filters: cancer, humans; and selected the checkpoint inhibitors that had been approved by the FDA by March 2021, i.e., "pembrolizumab", "nivolumab", "atezolizumab", "durvalumab", "cemiplimab", "avelumab", and "ipilimumab. Clinical trials with their checkpoint inhibitors as in their labeled indications, off-label use or their combinations with investigational immune checkpoint inhibitors or other treatment modalities were included. Studies describing supportive care or locoregional treatments; cellular, viral, or vaccine therapy; studies in the adjuvant or neoadjuvant setting; and pediatric studies were excluded. Overall, 173 articles reporting on relevant studies were identified. Using these articles, we compiled a data file of study-specific covariates for each study. We recorded the immunotherapeutic agent, tumor type and biomarker, and clinical outcomes (objective response rate and median values [point estimate] and confidence intervals for progression-free survival and overall survival. Using these data, we carried out meta-analyses for the three outcomes and meta-regression on study-specific covariates. The same data could be used for any alternative implementation of meta-analysis and meta-regression, using more structured inference models reflecting different levels of dependence based on the available study-specific covariates.

The Utility of NGS Analysis in Homologous Recombination Deficiency Tracking

Several tumor types have been efficiently treated with PARP inhibitors (PARPis), which are now approved for the treatment of ovarian, breast, prostate, and pancreatic cancers. The BRCA1/2 genes and mutations in many additional genes involved in the HR pathway may be responsible for the HRD phenomenon. The aim of the present study was to investigate the association between genomic loss of heterozygosity (gLOH) and alterations in 513 genes with targeted and immuno-oncology therapies in 406 samples using an NGS assay. In addition, the %gLOHs of 24 samples were calculated using the Affymetrix technology in order to compare the results obtained via the two methodologies. HR variations occurred in 20.93% of the malignancies, while BRCA1/2 gene alterations occurred in 5.17% of the malignancies. The %LOH was highly correlated with alterations in the BRCA1/2 genes, since 76.19% (16/21) of the BRCA1/2 positive tumors had a high %LOH value (p = 0.007). Moreover, the LOH status was highly correlated with the TP53 and KRAS statuses, but there was no association with the TMB value. Lin's concordance correlation coefficient for the 24 samples simultaneously examined via both assays was 0.87, indicating a nearly perfect agreement. In conclusion, the addition of gLOH analysis could assist in the detection of additional patients eligible for treatment with PARPis.

Correlation between biomarkers and treatment outcomes in diverse cancers: a systematic review and meta-analysis of phase I and II immunotherapy clinical trials

BACKGROUND

Many immuno-oncology (IO) trials are conducted without biomarker selection. We performed a meta-analysis of phase I/II clinical trials evaluating immune checkpoint inhibitors (ICIs) to determine the association between biomarkers and clinical outcomes, if any.

METHODS

A PubMed search for phase I/II clinical trials with drugs approved by the Food and Drug Administration (labelled, off-label, combined with investigational ICIs or other treatment modalities) from 2018 to 2020 was performed. The objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were compared between biomarker-positive and biomarker-negative groups, using studies that explored the correlation of biomarkers with outcomes.

RESULTS

Overall, 174 clinical studies that included 19,178 patients were identified, and 132 studies investigated>30 correlative biomarkers that included PD-L1 expression (≥1%, 111 studies), tumour mutational burden (20 studies) and microsatellite instability/mismatch repair deficiency (10 studies). Overall, 123, 46 and 30 cohorts (drugs, tumour types or biomarkers) with 11,692, 3065, and 2256 patient outcomes for ORR, PFS and OS, respectively, were analysed in correlation with biomarkers. Meta-analyses demonstrated that ICIs in patients with biomarker-positive tumours were associated with higher ORR (odds ratio 2.15 [95% CI, 1.79-2.58], p < 0.0001); and longer PFS (hazard ratio [HR] 0.55 [95% CI, 0.45-0.67], p < 0.0001), and OS (HR 0.65 [95% CI, 0.53-0.80], p < 0.0001) compared with those with biomarker-negative tumours. Significance for ORR and PFS was retained in multivariate analysis (p < 0.001) (OS, not included owing to the small number of trials reporting OS).

CONCLUSION

Our data suggest that IO biomarkers should be used in patient selection for ICIs. Prospective studies are warranted.

Investigation of Clinically Significant Molecular Aberrations in Patients with Prostate Cancer: Implications for Personalized Treatment, Prognosis and Genetic Testing

The data on tumor molecular profiling of European patients with prostate cancer is limited. Our aim was to evaluate the prevalence and prognostic and predictive values of gene alterations in unselected patients with prostate cancer. The presence of gene alterations was assessed in patients with histologically confirmed prostate cancer using the ForeSENTIA^® Prostate panel (Medicover Genetics), targeting 36 clinically relevant genes and microsatellite instability testing. The primary endpoint was the prevalence of gene alterations in homologous recombination repair (HRR) genes. Overall, 196 patients with prostate cancer were evaluated (median age 72.2 years, metastatic disease in 141 (71.9%) patients). Gene alterations were identified in 120 (61%) patients, while alteration in HRR genes were identified in 34 (17.3%) patients. The most commonly mutated HRR genes were ATM (17, 8.7%), BRCA2 (9, 4.6%) and BRCA1 (4, 2%). The presence of HRR gene alterations was not associated with advanced stage (p = 0.21), age at diagnosis (p = 0.28), Gleason score (p = 0.17) or overall survival (HR 0.72; 95% CI: 0.41-1.26; p = 0.251). We identified clinically relevant somatic gene alterations in European patients with prostate cancer. These molecular alterations have prognostic significance and therapeutic implications and/or may trigger genetic testing in selected patients. In the era of precision medicine, prospective research on the predictive role of these alterations for innovative treatments or their combinations is warranted.

Real-world Data and Economic Evaluation of Nivolumab in Previously Treated Non-small Cell Lung Cancer Greek Patients

BACKGROUND/AIM

Nivolumab is an FDA-approved immune checkpoint inhibitor (ICI) for patients with advanced, pre-treated non-small cell lung cancer (NSCLC). However, treatment profiles and patient outcomes often differ in routine clinical practice while the financial impact of approved therapies is largely unknown. In this study, we investigated the efficacy, tolerability, and economic impact of nivolumab in real-world settings (RWS) in Greece.

PATIENTS AND METHODS

Patients diagnosed with advanced pre-treated NSCLC, receiving nivolumab were recruited from October 2015 until November 2019 across 18 different clinical centers in Greece. Endpoints included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and safety. Cost analysis was conducted using a third-party public-payer perspective (National Organization for Healthcare Services Provision; EOPYY).

RESULTS

A total of 346 patients, median age 66.5 years, were included. With 43.4 months median follow-up, median PFS was 7.8 months and median OS 15.8 months. The 1-year OS rate was 56.5%, 2-year OS 38.8%, and 3-year OS 27.3%. The ORR was 29.5% and DCR 58.7%, with a median response duration of 26.8 months. Patients with objective response were more likely to experience long-term survival (HR=0.14, p<0.001). Only 8.4% of patients experienced grade 3-4 adverse events. The presence of immune-related adverse events was associated with improved OS (HR=0.77, p=0.043). Nivolumab-associated economic burden accounted for €2,214.10 per cycle for each patient, mainly attributed to drug-acquisition costs.

CONCLUSION

This is the first report of real-world efficacy, safety, and economic burden of nivolumab in pre-treated patients with NSCLC in Greece. Indirectly compared to clinical trials, nivolumab was associated with improved efficacy in RWS, further supporting its use in clinical practice and providing insights on clinical prognosticators. The main cost component affecting the nivolumab economic burden was drug-acquisition costs, while toxicity-associated cost was negligible.

Clinical trial design in the era of precision medicine

Recent rapid biotechnological breakthroughs have led to the identification of complex and unique molecular features that drive malignancies. Precision medicine has exploited next-generation sequencing and matched targeted therapy/immunotherapy deployment to successfully transform the outlook for several fatal cancers. Tumor and liquid biopsy genomic profiling and transcriptomic, immunomic, and proteomic interrogation can now all be leveraged to optimize therapy. Multiple new trial designs, including basket and umbrella trials, master platform trials, and N-of-1 patient-centric studies, are beginning to supplant standard phase I, II, and III protocols, allowing for accelerated drug evaluation and approval and molecular-based individualized treatment. Furthermore, real-world data, as well as exploitation of digital apps and structured observational registries, and the utilization of machine learning and/or artificial intelligence, may further accelerate knowledge acquisition. Overall, clinical trials have evolved, shifting from tumor type-centered to gene-directed and histology-agnostic trials, with innovative adaptive designs and personalized combination treatment strategies tailored to individual biomarker profiles. Some, but not all, novel trials now demonstrate that matched therapy correlates with superior outcomes compared to non-matched therapy across tumor types and in specific cancers. To further improve the precision medicine paradigm, the strategy of matching drugs to patients based on molecular features should be implemented earlier in the disease course, and cancers should have comprehensive multi-omic (genomics, transcriptomics, proteomics, immunomic) tumor profiling. To overcome cancer complexity, moving from drug-centric to patient-centric individualized combination therapy is critical. This review focuses on the design, advantages, limitations, and challenges of a spectrum of clinical trial designs in the era of precision oncology.

Neoadjuvant treatment in ovarian cancer: New perspectives, new challenges

Ovarian cancer remains the leading cause of death from gynecological cancer. Survival is significantly related to the stage of the disease at diagnosis. Of quite importance is primary cytoreductive surgery, having as a goal to remove all visible tumor tissue, and is the standard primary treatment in combination with platinum-based chemotherapy for patients with advanced ovarian carcinoma.

Neo-adjuvant chemotherapy (NACT) has been implemented mostly in treating advanced disease, with studies performed having numerous limitations. Data extrapolated from these studies have not shown inferiority survival of NACT, compared to primary debulking surgery. The role of NACT is of particular interest because of the intrinsic mechanisms that are involved in the process, which can be proven as therapeutic approaches with enormous potential. NACT increases immune infiltration and programmed death ligand-1 (PDL-1) expression, induces local immune activation, and can potentiate the immunogenicity of immune-exclude high grade serous ovarian tumors, while the combination of NACT with bevacizumab, PARP inhibitors or immunotherapy remains to be evaluated. This article summarizes all available data on studies implementing NACT in the treatment of ovarian cancer, focusing on clinical outcomes and study limitations. High mortality rates observed among ovarian cancer patients necessitates the identification of more effective treatments, along with biomarkers that will aid treatment individualization.

Lung cancer as a predominant feature in a patient with Peutz-Jeghers syndrome: Case report

Peutz–Jeghers syndrome (PJS) is characterized by mucocutaneous pigmentation and gastrointestinal hamartomatous polyposis, which can lead to intussusception. PJS patients face high lifetime risks for various cancer types, with the majority of patients being diagnosed with tumors along the gastrointestinal tract. Herein, we present the case of a 34‐year‐old man who carried a germline STK11 pathogenic variant, while lacking the cardinal features of PJS syndrome. Interestingly, he was diagnosed with lung adenocarcinoma despite being a never‐smoker. Tumor testing revealed clinically relevant molecular alterations, including the known germline pathogenic variant STK11, a KRAS somatic pathogenic variant, and FGFR3 gene amplification. Treatment with standard chemotherapy and immunotherapy did not have a clinical benefit. Due to clinical deterioration, the patient deceased 18 months after his initial diagnosis prior to having the chance for targeted therapy. Identification of rare hereditary cancer syndromes and the respective presence of tumor biomarkers can provide important alternatives to targeted treatments, including immunotherapy in patients with tumors unresponsive to conventional treatment protocols. This case highlights that although only a small proportion of lung cancer diagnoses will be due to hereditary predisposition, STK11 germline carriers should be under close surveillance for early detection of lung cancer.

Wedding of Molecular Alterations and Immune Checkpoint Blockade: Genomics as a Matchmaker

The development of checkpoint blockade immunotherapy has transformed the medical oncology armamentarium. But despite its favorable impact on clinical outcomes, immunotherapy benefits only a subset of patients, and a substantial proportion of these individuals eventually manifest resistance. Serious immune-related adverse events and hyperprogression have also been reported. It is therefore essential to understand the molecular mechanisms and identify the drivers of therapeutic response and resistance. In this review, we provide an overview of the current and emerging clinically relevant genomic biomarkers implicated in checkpoint blockade outcome. US Food and Drug Administration-approved molecular biomarkers of immunotherapy response include mismatch repair deficiency and/or microsatelliteinstability and tumor mutational burden of at least 10 mutations/megabase. Investigational genomic-associated biomarkers for immunotherapy response include alterations of the following genes/associated pathways: chromatin remodeling (ARID1A, PBRM1, SMARCA4, SMARCB1, BAP1), major histocompatibility complex, specific (eg, ultraviolet, APOBEC) mutational signatures, T-cell receptor repertoire, PDL1, POLE/POLD1, and neo-antigens produced by the mutanome, those potentially associated with resistance include β2-microglobulin, EGFR, Keap1, JAK1/JAK2/interferon-gamma signaling, MDM2, PTEN, STK11, and Wnt/Beta-catenin pathway alterations. Prospective clinical trials are needed to assess the role of a composite of these biomarkers to optimize the implementation of precision immunotherapy in patient care.

Responses to SARS-CoV-2 Vaccination in Patients with Cancer (ReCOVer Study): A Prospective Cohort Study of the Hellenic Cooperative Oncology Group

Data on the effectiveness and safety of approved SARS-CoV-2 vaccines in cancer patients are limited. This observational, prospective cohort study investigated the humoral immune response to SARS-CoV-2 vaccination in 232 cancer patients from 12 HeCOG-affiliated oncology departments compared to 100 healthcare volunteers without known active cancer. The seropositivity rate was measured 2-4 weeks after two vaccine doses, by evaluating neutralising antibodies against the SARS-CoV-2 spike protein using a commercially available immunoassay. Seropositivity was defined as ≥33.8 Binding-Antibody-Units (BAU)/mL. A total of 189 patients and 99 controls were eligible for this analysis. Among patients, 171 (90.5%) were seropositive after two vaccine doses, compared to 98% of controls (p = 0.015). Most seronegative patients were males (66.7%), >70-years-old (55.5%), with comorbidities (61.1%), and on active treatment (88.9%). The median antibody titers among patients were significantly lower than those of the controls (523 vs. 2050 BAU/mL; p < 0.001). The rate of protective titers was 54.5% in patients vs. 97% in controls (p < 0.001). Seropositivity rates and IgG titers in controls did not differ for any studied factor. In cancer patients, higher antibody titers were observed in never-smokers (p = 0.006), women (p = 0.022), <50-year-olds (p = 0.004), PS 0 (p = 0.029), and in breast or ovarian vs. other cancers. Adverse events were comparable to registration trials. In this cohort study, although the seropositivity rate after two vaccine doses in cancer patients seemed satisfactory, their antibody titers were significantly lower than in controls. Monitoring of responses and further elucidation of the clinical factors that affect immunity could guide adaptations of vaccine strategies for vulnerable subgroups.

Association of the advanced lung cancer inflammation index (ALI) with immune checkpoint inhibitor efficacy in patients with advanced non-small-cell lung cancer

Background

The advanced lung cancer inflammation index [ALI: body mass index × serum albumin/neutrophil-to-lymphocyte ratio (NLR)] reflects systemic host inflammation, and is easily reproducible. We hypothesized that ALI could assist guidance of non-small-cell lung cancer (NSCLC) treatment with immune checkpoint inhibitors (ICIs).

Patients and methods

This retrospective study included 672 stage IV NSCLC patients treated with programmed death-ligand 1 (PD-L1) inhibitors alone or in combination with chemotherapy in 25 centers in Greece and Germany, and a control cohort of 444 stage IV NSCLC patients treated with platinum-based chemotherapy without subsequent targeted or immunotherapy drugs. The association of clinical outcomes with biomarkers was analyzed with Cox regression models, including cross-validation by calculation of the Harrell's C-index.

Results

High ALI values (>18) were significantly associated with longer overall survival (OS) for patients receiving ICI monotherapy [hazard ratio (HR) = 0.402, P < 0.0001, n = 460], but not chemo-immunotherapy (HR = 0.624, P = 0.111, n = 212). Similar positive correlations for ALI were observed for objective response rate (36% versus 24%, P = 0.008) and time-on-treatment (HR = 0.52, P < 0.001), in case of ICI monotherapy only. In the control cohort of chemotherapy, the association between ALI and OS was weaker (HR = 0.694, P = 0.0002), and showed a significant interaction with the type of treatment (ICI monotherapy versus chemotherapy, P < 0.0001) upon combined analysis of the two cohorts. In multivariate analysis, ALI had a stronger predictive effect than NLR, PD-L1 tumor proportion score, lung immune prognostic index, and EPSILoN scores. Among patients with PD-L1 tumor proportion score ≥50% receiving first-line ICI monotherapy, a high ALI score >18 identified a subset with longer OS and time-on-treatment (median 35 and 16 months, respectively), similar to these under chemo-immunotherapy.

Conclusions

The ALI score is a powerful prognostic and predictive biomarker for patients with advanced NSCLC treated with PD-L1 inhibitors alone, but not in combination with chemotherapy. Its association with outcomes appears to be stronger than that of other widely used parameters. For PD-L1-high patients, an ALI score >18 could assist the selection of cases that do not need addition of chemotherapy.

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ALI is prognostic and predictive for patients with advanced NSCLC treated with immunotherapy monotherapy, but not chemo-immunotherapy.

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Its association with outcomes is stronger than that of other parameters (PD-L1 TPS, NLR, lung immune prognostic index, EPSILoN).

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For PD-L1-high patients, an ALI score >18 could assist the selection of cases that do not need addition of chemotherapy.

Follow-up of tissue genomics in BRCA1/2 carriers who underwent prophylactic surgeries

PURPOSE

The genomic status of non-malignant tissues from carriers of pathogenic germline BRCA1/2 (gBRCA1/2) variants may reveal information towards individualized prophylaxis. We performed spatiotemporal tissue genotype comparisons in a real-life cohort of gBRCA1/2 carriers of Greek origin, who underwent multiple risk-reducing/prophylactic surgeries at various time points.

METHODS

Fifty-three women (median age 36 years) within cancer families were observed for up to 37.5 years; 43 were cancer carriers and 10 were healthy carriers. Histology review and genotyping were performed for 187 paraffin tissues (average: 3.5 per carrier) including 46 carcinomas (40 breast) and 141 non-malignant breast and gynecological samples.

RESULTS

High allelic imbalance (AI) and somatic pathogenic TP53 variants were present in cancer carriers only (p values < 0.0001). High AI was associated with gBRCA1/2 indels (p < 0.0001) and gBRCA2 alterations (p = 0.0109). Somatic (pathogenic) variants were infrequently shared between non-malignant tissues and matched carcinomas. Aberrations of gBRCA1 variant heterozygosity were noticed in tissues from cancer carriers only (13/43, 30.2%). These pertained to classic LOH (neoplastic lesions in 9/43 carriers, 20.9%) and under-representation of the germline variants (5 samples, 4 non-malignant, all in the breast). Both aberrations coexisted in matched samples in one case. Over time, germline variant heterozygosity prevailed in non-malignant tissues; intra-carrier genomic alterations were aggravated (21.1%), ameliorated (26.3%) or remained stable.

CONCLUSION

This real-life case study supports the need to address tissue genotypes from prophylactic surgeries in combination with polygenic scores towards personalized prophylaxis. To this end, knowing the traditionally classified pathogenic potential of a gBRCA1/2 variant may not be enough.

Real-world clinical outcome and toxicity data and economic aspects in patients with advanced breast cancer treated with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors combined with endocrine therapy: the experience of the Hellenic Cooperative Oncology Group

Background

We evaluated real-world clinical outcomes and toxicity data and assessed treatment-related costs in patients with advanced breast cancer who received treatment with cyclin-dependent kinase inhibitors (CDKi).

Patients and methods

We conducted a prospective–retrospective analysis of patients with advanced hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer who received a CDKi, in combination with endocrine therapy, at any line of treatment. The primary endpoint was progression-free survival (PFS). Cost analysis was conducted from a public third-payer (National Organization for Healthcare Services Provision (EOPYY)) perspective, assessing only costs related to direct medical care, including drug therapy costs and adverse drug reaction (ADR)-related costs.

Results

From July 2015 to October 2019, 365 women received endocrine therapy combined with CDKi; median age was 61 years, postmenopausal 290 (80.6%) patients. CDKi were administered as first-line treatment in 149 (40.9%) patients, second-line treatment in 96 (26.4%) and third-line treatment and beyond in 119 (32.7%) patients. The most common adverse events were neutropenia, anaemia, thrombocytopenia and fatigue. Grade 3–4 adverse events occurred in 86 (23.6%) patients, whereas 8 (2.2%) patients permanently discontinued treatment due to toxicity. The median PFS for patients who received CDKi as first-line, second-line and third-line treatment and beyond was 18.7, 12 and 7.4 months, respectively. The median overall survival since the initiation of CDKi treatment was 29.9 months (95% CI: 23.0–not yet reached (NR)). The mean pharmaceutical therapy cost estimated per cycle was 2 724.12 € for each patient, whereas the main driver of the ADR-related costs was haematological adverse events.

Conclusions

Treatment with CDKi was well tolerated, with a low drug discontinuation rate. Patients who received CDKi as first-line treatment had improved PFS and OS compared with second-line treatment and beyond. The main component of direct medical costs assessed in the cost analysis comprises CDKi pharmaceutical therapy costs.

Trial registration number

NCT04133207

Real-world safety and efficacy data of immunotherapy in patients with cancer and autoimmune disease: the experience of the Hellenic Cooperative Oncology Group

BACKGROUND

Data on the safety and efficacy of immune checkpoint inhibitors (ICI) in patients with concurrent autoimmune diseases (AID) are limited.

METHODS

We performed a retrospective multicenter review of medical records of patients with cancer and underlying AID who received ICI. The primary endpoint was progression-free survival (PFS).

RESULTS

Among 123 patients with pre-existing AID who received ICI, the majority had been diagnosed with non-small cell lung cancer (NSCLC, 68.3%) and melanoma (14.6%). Most patients had a rheumatologic (43.9%), or an endocrine disorder (21.1%). Overall, 74 (60.2%) patients experienced an immune-related adverse event (irAE) after ICI initiation, AID flare (25.2%), or new irAE (35%). Frequent irAEs included thyroiditis, dermatitis and colitis. ICI was permanently discontinued due to unacceptable (8.1%) or fatal (0.8%) toxicity. In patients with NSCLC, corticosteroid treatment at the initiation of immunotherapy was associated with poor PFS (HR = 2.78, 95% CI 1.40-5.50, p = 0.003). The occurrence of irAE was associated with increased PFS (HR = 0.48, 95% CI 0.25-0.92, p = 0.026). Both parameters maintained their independent prognostic significance.

CONCLUSIONS

ICI in patients with cancer and pre-existing AID is associated with manageable toxicity that infrequently requires treatment discontinuation. However, since severe AID flare might occur, expected ICI efficacy and toxicity must be balanced.

CLINICAL TRIAL IDENTIFIER

NCT04805099.

Tumor Genotyping and Homologous Recombination Repair Gene Variants in Patients With Epithelial Ovarian Cancer: Is Pathogenic Enough?

Our hypothesis was that the predictive accuracy of pathogenic variants in genes participating in the homologous recombination repair (HRR) system in patients with epithelial ovarian cancer (EOC) could be improved by considering additional next-generation sequencing (NGS) metrics. NGS genotyping was performed in tumor tissue, retrospectively and prospectively collected from patients with EOC, diagnosed from 8/1998 to 10/2016. Variants were considered clonal when variant allele frequencies corresponded to >25%. The primary endpoint was overall survival (OS). This study included 501 patients with EOC, predominantly with high-grade serous (75.2%) and advanced stage tumors (81.7%); median age was 58 years (22-84). Pathogenic and clonal pathogenic variants in HRR and/or TP53 genes were identified in 72.8% and 66.5% tumors, respectively. With a median follow-up of 123.9 months, the presence of either pathogenic or clonal pathogenic HRR-only variants was associated with longer OS compared to HRR/TP53 co-mutation (HR=0.54; 95% CI, 0.34-0.87, Wald's p=0.012 and HR=0.45; 95% CI, 0.27-0.78, Wald's p=0.004, respectively). However, only the presence of clonal HRR-only variants was independently associated with improved OS (HR=0.55; 95% CI, 0.32-0.94, p=0.030). Variant clonality and co-occuring TP53 variants affect the predictive value of HRR pathogenic variants for platinum agents in patients with EOC.

Clinical Trial Registration

[ClinicalTrials.gov], identifier [NCT04716374].

Clinical Significance of Germline Cancer Predisposing Variants in Unselected Patients with Pancreatic Adenocarcinoma

Our aim was to determine the prevalence, prognostic and predictive role of germline pathogenic/likely pathogenic variants (P/LPVs) in cancer predisposing genes in patients with pancreatic ductal adenocarcinoma (PDAC). Germline testing of 62 cancer susceptibility genes was performed on unselected patients diagnosed from 02/2003 to 01/2020 with PDAC, treated at Hellenic Cooperative Oncology Group (HeCOG)-affiliated Centers. The main endpoints were prevalence of P/LPVs and overall survival (OS). P/LPVs in PDAC-associated and homologous recombination repair (HRR) genes were identified in 22 (4.0%) and 42 (7.7%) of 549 patients, respectively. P/LPVs were identified in 16 genes, including ATM (11, 2.0%) and BRCA2 (6, 1.1%), while 19 patients (3.5%) were heterozygotes for MUTYH P/LPVs and 9 (1.6%) carried the low-risk allele, CHEK2 p.(Ile157Thr). Patients carrying P/LPVs had improved OS compared to non-carriers (22.6 vs. 13.9 months, p = 0.006). In multivariate analysis, there was a trend for improved OS in P/LPV carriers (p = 0.063). The interaction term between platinum exposure and mutational status of HRR genes was not significant (p-value = 0.35). A significant proportion of patients with PDAC carries clinically relevant germline P/LPVs, irrespectively of age, family history or disease stage. The predictive role of these P/LPVs has yet to be defined. ClinicalTrials.gov Identifier: NCT03982446.

Transcriptomics and solid tumors: The next frontier in precision cancer medicine

Transcriptomics, which encompasses assessments of alternative splicing and alternative polyadenylation, identification of fusion transcripts, explorations of noncoding RNAs, transcript annotation, and discovery of novel transcripts, is a valuable tool for understanding cancer mechanisms and identifying biomarkers. Recent advances in high-throughput technologies have enabled large-scale gene expression profiling. Importantly, RNA expression profiling of tumor tissue has been successfully used to determine clinically actionable molecular alterations. The WINTHER precision medicine clinical trial was the first prospective trial in diverse solid malignancies that assessed both genomics and transcriptomics to match treatments to specific molecular alterations. The use of transcriptome analysis in WINTHER and other trials increased the number of targetable -omic changes compared to genomic profiling alone. Other applications of transcriptomics involve the evaluation of tumor and circulating noncoding RNAs as predictive and prognostic biomarkers, the improvement of risk stratification by the use of prognostic and predictive multigene assays, the identification of fusion transcripts that drive tumors, and an improved understanding of the impact of DNA changes as some genomic alterations are silenced at the RNA level. Finally, RNA sequencing and gene expression analysis have been incorporated into clinical trials to identify markers predicting response to immunotherapy. Many issues regarding the complexity of the analysis, its reproducibility and variability, and the interpretation of the results still need to be addressed. The integration of transcriptomics with genomics, proteomics, epigenetics, and tumor immune profiling will improve biomarker discovery and our understanding of disease mechanisms and, thereby, accelerate the implementation of precision oncology.

Review of precision cancer medicine: Evolution of the treatment paradigm

In recent years, biotechnological breakthroughs have led to identification of complex and unique biologic features associated with carcinogenesis. Tumor and cell-free DNA profiling, immune markers, and proteomic and RNA analyses are used to identify these characteristics for optimization of anticancer therapy in individual patients. Consequently, clinical trials have evolved, shifting from tumor type-centered to gene-directed, histology-agnostic, with innovative adaptive design tailored to biomarker profiling with the goal to improve treatment outcomes. A plethora of precision medicine trials have been conducted. The majority of these trials demonstrated that matched therapy is associated with superior outcomes compared to non-matched therapy across tumor types and in specific cancers. To improve the implementation of precision medicine, this approach should be used early in the course of the disease, and patients should have complete tumor profiling and access to effective matched therapy. To overcome the complexity of tumor biology, clinical trials with combinations of gene-targeted therapy with immune-targeted approaches (e.g., checkpoint blockade, personalized vaccines and/or chimeric antigen receptor T-cells), hormonal therapy, chemotherapy and/or novel agents should be considered. These studies should target dynamic changes in tumor biologic abnormalities, eliminating minimal residual disease, and eradicating significant subclones that confer resistance to treatment. Mining and expansion of real-world data, facilitated by the use of advanced computer data processing capabilities, may contribute to validation of information to predict new applications for medicines. In this review, we summarize the clinical trials and discuss challenges and opportunities to accelerate the implementation of precision oncology.

Oncologist Burnout Syndrome in Eastern Europe: Results of the Multinational Survey

PURPOSE

Burnout is defined as a three-dimensional syndrome-emotional exhaustion (EE), depersonalization (DP), and reduced personal accomplishment (PA)-caused by chronic occupational stress. The aim of the current study was to investigate the prevalence of burnout among oncologists in Eastern Europe and to identify the contributing factors.

METHODS

The study was conducted as an online survey between October 2017 and March 2018. Oncologists (including medical, radiation, clinical, and surgical oncologists) from 19 countries were invited to participate. The survey consisted of 30 questions, including the standardized burnout instrument, Maslach Burnout Inventory, and eight demographic questions. Burnout risk was scored according to the scoring manual for health care workers.

RESULTS

The study included 637 oncologists. Overall, 28% were at low or intermediate risk and 72% were at high risk for burnout. Forty-four percent of participants were at high risk for EE, 28.7% for DP, and 47.3% for PA. EE risk was associated with female sex. DP risk was highest among clinical and radiation oncologists, whereas PA risk was positively correlated with years of service, percentage of cancer deaths, and availability of the number of oncologists. In multivariate logistic regression analysis, burnout was significantly associated with standardized cancer mortality and fewer years of practice.

CONCLUSION

Burnout among oncologists in Eastern Europe is high, and younger oncologists are the most vulnerable group. Preventive measures should be taken to address this issue, which negatively affects optimal care delivery and poses a threat to oncologists' health and well-being.

Pathogenic mutations and overall survival in 3,084 patients with cancer: the Hellenic Cooperative Oncology Group Precision Medicine Initiative

Background: We evaluated the association between pathogenic mutations and overall survival (OS) in patients with cancer referred to Hellenic Cooperative Oncology Group–affiliated Departments.

Patients and methods: Patients referred from 12/1980 to 1/2017 had molecular testing (for research) of archival tumor tissue collected at the time of first diagnosis (non-metastatic, 81%; metastatic, 19%). Tumor-specific gene panels (16-101 genes) were used to identify pathogenic mutations in clinically relevant genes. NGS genotyping was performed at the Laboratory of Molecular Oncology, Aristotle University of Thessaloniki. Annotation of mutations was performed at MD Anderson Cancer Center.

Results: We analyzed 3,084 patients (median age, 57 years; men, 22%) with sequencing data. Overall, 1,775 (58% of 3,084) patients had pathogenic mutations. The median follow-up was 7.52 years (95% CI, 7.39-7.61). In patients with non-metastatic tumors, after stratification by tumor type, increasing age, higher grade, and histology other than adenocarcinoma were associated with shorter OS. OS was also shorter in patients with pathogenic TP53 (HR=1.36; p<0.001), MLL3 (HR=1.64; p=0.005), and BRCA1 (HR=1.46; p=0.047) mutations compared to wild-type genes. In multivariate analyses, independent prognostic factors predicting shorter OS were pathogenic mutations in TP53 (HR=1.37, p=0.002) and MLL3 (HR=1.50, p=0.027); increasing age (HR=1.02, p<0.001); and increasing grade (HR=1.46, p<0.001). In patients with metastatic cancer, older age and higher grade were associated with shorter OS and maintained their independent prognostic significance (increasing age, HR=1.03, p<0.001 and higher grade, HR=1.73, p<0.001).

Conclusions: Analysis of molecular data reveals prognostic biomarkers, regardless of tissue or organ of origin to improve patient management.

Pathology of BRCA1- and BRCA2-associated Breast Cancers: Known and Less Known Connections

INTRODUCTION

BRCA1/BRCA2 mutation carriers indefinitely comprise a distinct group of patients with breast cancer (BC), with their tumors displaying specific pathologic characteristics. Although these connections are known, they are not fully elucidated. We therefore sought to investigate the clinicopathologic characteristics and overall survival of Greek patients with BC carrying BRCA1/BRCA2 mutations.

PATIENTS AND METHODS

Greek patients with BC diagnosed between 1999 and 2016, fulfilling the National Comprehensive Cancer Network criteria for genetic testing, were analyzed for BRCA1/BRCA2 mutations by Sanger sequencing or by a 94-gene panel. Medical records and pathology reports were retrospectively reviewed to retrieve patient and tumor baseline characteristics. Potential associations with mutation status were assessed using the Fisher exact, Pearson χ², and Mann-Whitney tests.

RESULTS

Of 2096 selected patients with BC, we identified 297 (14.2%) BRCA1 and 88 (4.2%) BRCA2 carriers. The mean age at BC diagnosis was 40 and 42.6 years, respectively (P = .02). Tumor histologic subtypes in BRCA1 and BRCA2 carriers were predominantly ductal (79%) followed by medullary (10%), and ductal (72%) followed by lobular (15%), respectively. A significantly higher percentage of BRCA2 tumors were human epidermal growth factor receptor 2-positive, compared with BRCA1 tumors (21.7% vs. 5.8%; P < .001). Second primary cancer diagnosis was more frequent in BRCA1 compared with BRCA2 mutation carriers (36.2% vs. 10.7%; P < .001), whereas there was no difference in 15-year overall survival (hazard ratio, 0.92; 95% confidence interval, 0.48-1.83; P = .804) between the 2 groups.

CONCLUSIONS

These data confirm established observations in the pathology of BRCA-related tumors and provide further insight on the association of rare histologic entities with mutations in these genes, which can be clinically beneficial.

Abstract 486: Pathogenic drivers and their comutations in genes frequently altered in cancer

Background - aim: The as yet publicized results from Precision Oncology trials highlight the need to define parameters that may interfere with the actionability of common pathogenic drivers. One such parameter may be the presence of multiple drivers within the same tumor. Here, we investigated the properties of single and coexisting pathogenic mutations in genes frequently altered and targeted across cancers.

Methods: We examined informative deep sequencing data for TP53, PIK3CA, KRAS and BRCA1 from 2672 paraffin tumors that were obtained at first diagnosis (88% stage I-III; 12% stage IV) from patients with breast (n=1745), colorectal (n=524), nasopharyngeal (n=143), gastric (n=102), biliary tree (n=81), nasopharyngeal (n=143) and ovarian (n=77) cancer. Single mutation corresponds to the presence of a pathogenic mutation in only one of these genes; co-mutation, to the presence of pathogenic mutations in ≥2 genes. We examined the status of single and co-mutations compared to disease stage and patient overall survival (OS) stratified by tumor type.

Results: Pathogenic mutations in any of the 4 genes were observed in 1337 (50% of all tumors) and co-mutation in 347 tumors (28% of tumors with mutations in these genes). Single mutations and co-mutations were observed in 481 (36.0%) and 322 (24.1%) tumors for TP53, respectively; in 350 (26.0%) and 198 (14.8%) for PIK3CA; in 80 (6%) and 198 (14.8%) for KRAS; and, in 51 (3.9%) and 120 (9.0%) for BRCA1. Co-mutations of BRCA1 and KRAS were more frequent than single mutations in the two genes across tumor types (p’s&lt;0.010). The same was observed for PIK3CA and TP53 except for breast cancer, where single mutations were more frequent than co-mutations (p’s&lt;0.001). Compared to stage I-III, stage IV tumors were more frequently mutated in TP53, KRAS and BRCA1 (p’s&lt;0.010) but were significantly less often mutated in PIK3CA (p&lt;0.001). Co-mutation rates for BRCA1, KRAS and TP53 did not differ between stage I-III and IV tumors but these were significantly different for PIK3CA (33.5% in I-III vs. 64.3% in IV; p&lt;0.001). Upon stratification by tumor type, in stage I-III disease, compared to tumors with co-mutations, single BRCA1, TP53 and KRAS mutations conferred similar OS, but single PIK3CA mutations conferred significantly lower risk for death (HR 0.52; 95%CI 0.35-0.77; p&lt;0.001). In stage IV disease, compared to no mutations, single KRAS or TP53 were associated with poor OS (p=0.017 and p=0.025, respectively) but this effect disappeared in patients with KRAS/TP53 co-mutated tumors.

Conclusions: Co-mutation patterns of known cancer drivers vary with respect to the affected gene, tumor type and disease stage. Known drivers have distinct prognostic impact when occurring singly or co-altered in the non-metastatic and metastatic setting, which may need to be considered in Precision Oncology trials.

Citation Format: Vassiliki Kotoula, Elena Fountzilas, Georgia-Angeliki Koliou, Kyriaki Papadopoulou, Eleni Giannoulatou, Ioannis Tikas, Flora Zagouri, Christos Christodoulou, Georgios Pentheroudakis, Angelos Koutras, Dimitrios Pectasides, George Fountzilas. Pathogenic drivers and their comutations in genes frequently altered in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 486.

Prognostic implications of mismatch repair deficiency in patients with nonmetastatic colorectal and endometrial cancer

Background

The clinical relevance of mismatch repair (MMR) status in patients with nonmetastatic cancer across tumour types remains unclear. Our goal was to investigate the prognostic role of MMR deficiency in patients with stage I-III colorectal and endometrial cancer.

Methods

Patients with nonmetastatic colorectal and endometrial cancer with tumour tissue available for analysis were identified through the Hellenic Cooperative Oncology Group (HeCOG)'s tumour repository. Patients had been referred to Departments of Medical Oncology affiliated with HeCOG. MMR protein expression was evaluated by immunohistochemistry. The primary outcome measure was overall survival (OS).

Results

From May 1990 to September 2012, 1158 patients with nonmetastatic colorectal (N = 991) and endometrial cancer (N = 167) were identified (median age: 64 years, men: 544). All patients with colorectal and 109 (65%) with endometrial cancer had received adjuvant treatment. MMR deficiency was observed in 114 (11.5%) of colorectal and 80 (47.9%) of endometrial tumours. More commonly deficient proteins were PMS2 (69 patients, 7%) and MLH1 (63 patients, 6.5%) in colorectal cancer and MSH2 (58 patients, 34.7%) in endometrial cancer. Colorectal MMR-deficient (dMMR) tumours were more likely to be right sided (65 % dMMR vs 27 % proficient MMR, pMMR; p < 0.001), high grade (31% vs 15%, χ², p < 0.001) and with a mucinous component (64% vs 42%, p < 0.001). Endometrial dMMR tumours were more often of endometrioid histology (51.4 % endometrioid vs 20 % serous/clear cell, p = 0.020). Compared with MMR proficiency, MMR deficiency was associated with improved OS in patients with endometrial cancer (HR = 0.38, 95% CI 0.20 to 0.76, p = 0.006), but not in patients with colorectal cancer (HR = 0.73, 95% CI 0.49 to 1.09, p = 0.130). After adjusting for age, stage and grade, MMR deficiency maintained its favourable prognostic significance in patients with endometrial cancer (HR = 0.42, 95% CI 0.20 to 0.88, p = 0.021).

Conclusions

DMMR was associated with improved outcomes in patients with nonmetastatic endometrial cancer, but not in patients with nonmetastatic colorectal cancer who received adjuvant chemotherapy.

Prognostic significance of tumor genotypes and CD8+ infiltrates in stage I-III colorectal cancer

Background

We explored the clinical significance of tumor genotypes and immunophenotypes in non-metastatic colorectal cancer (CRC).

Methods

In primary tumors (paraffin blocks) from 412 CRC patients treated with adjuvant chemotherapy, we examined pathogenic mutations (panel NGS; 347 informative); mismatch repair (MMR) immunophenotype (360 informative); and CD8+ lymphocyte density (high – low; 412 informative). The primary outcome measure was disease-free survival (DFS).

Results

We evaluated 1713 pathogenic mutations (median: 3 per tumor; range 0-49); 118/412 (28.6%) tumors exhibited high CD8+ density; and, 40/360 (11.1%) were MMR-deficient. Compared to MMR-proficient, MMR-deficient tumors exhibited higher CD8+ density (chi-square, p<0.001) and higher pathogenic mutation numbers (p=0.003). High CD8+ density was an independent favorable prognosticator (HR=0.49, 95%CI 0.29-0.84, Wald's p=0.010). Pathogenic BRCA1 and ARID1A mutations were inversely associated with each other (p<0.001), were not associated with MMR-deficiency or CD8+ density, but both independently predicted for unfavorable DFS (HR=1.98, 95%CI 1.12-3.48, p=0.018 and HR=1.99, 95%CI 1.11-3.54, p=0.020, respectively).

Conclusion

In non-metastatic CRC, high CD8+ lymphocyte density confers a favorable prognosis and may be developed as a single marker in routine diagnostics. The unfavorable prognostic effect of pathogenic BRCA1 and ARID1A mutations is a novel observation that, if further validated, may improve treatment selection.

Treating EGFR-Mutated Oncogene-Addicted Advanced Non-Small-Cell Lung Cancer in the Era of Economic Crisis in Greece: Challenges and Opportunities

PURPOSE

Because of the profound financial crisis that commenced in Greece in 2010, severe cuts in health care spending and other restriction measures led to significant delays in the reimbursement of novel antineoplastic agents. In 2011, the Hellenic Society of Medical Oncology initiated a program of early access to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors for the treatment of patients with advanced, EGFR-mutant non-small-cell lung cancer (NSCLC). We evaluated treatment patterns and clinical outcomes in patients with EGFR-mutant or wild-type disease treated at a large center in Greece throughout the period of financial crisis.

PATIENTS AND METHODS

From 2011 through 2015, 252 patients with newly diagnosed advanced NSCLC were treated at the Department of Medical Oncology of the Papageorgiou Hospital, a tertiary cancer center in northern Greece. We retrospectively reviewed patient medical records to obtain clinicopathologic characteristics, EGFR mutation status, and follow-up data. The primary end point was time to treatment failure.

RESULTS

Of the 198 evaluable patients, 25 (12%) had EGFR mutations. All patients with EGFR mutations except one received treatment with an EGFR tyrosine kinase inhibitor. Median times to treatment failure for patients with EGFR-mutant and wild-type disease were 15.8 and 7.1 months, respectively (hazard ratio, 0.58; 95% CI, 0.35 to 0.95; P = .031). There was no difference in overall survival between the two groups ( P = .293). No deviation from treatment guidelines or discontinuation of treatment regimens occurred because of logistic reasons or drug shortages.

CONCLUSION

Despite restrictions in the reimbursement policy and accompanying controls in the use of high-cost medicines, the national program enabled treatment of patients with EGFR-mutant NSCLC according to established guidelines. Therefore, the clinical outcomes of such patients treated in Greece during the economic crisis were in accordance with international standards.

A phase I clinical trial of hepatic arterial infusion of oxaliplatin and oral capecitabine, with or without intravenous bevacizumab, in patients with advanced cancer and predominant liver involvement

BACKGROUND

We investigated hepatic arterial infusion (HAI) oxaliplatin combined with capecitabine +/- bevacizumab in advanced cancer with predominant liver involvement.

METHODS

Patients received HAI oxaliplatin (140 mg/m²) and escalating doses of capecitabine (500, 750, and 1000 mg/m²), with (Group 1) or without (Group 2) bevacizumab (10 mg/kg IV). A 3 + 3 dose design was used, followed by an expansion phase.

RESULTS

From 9/2009 to 2/2014, 61 patients (34 men, 27 women) were enrolled (Group 1 = 44; Group 2 = 17). Patients were treated in Group 2 if they had contraindications to bevacizumab (n = 13) or if there was no opening in Group 1 (n = 4). The median age was 60 years (range, 20-88). The most common cancers were colorectal (22 patients), liver (12), pancreatic (7), breast (4), and biliary tract (4). The median number of prior therapies was 3 (range, 1-12); 32 (53%) patients had received oxaliplatin. The dose-limiting toxicity was Grade 3 diarrhea and occurred in 2 patients receiving 1000 mg/m² capecitabine. The maximum tolerated dose was HAI oxaliplatin 140 mg/m², capecitabine 750 mg/m², and bevacizumab 10 mg/kg. The most common toxicities were nausea/vomiting, anemia, thrombocytopenia, neutropenia, and hypomagnesemia. The rates of partial response and stable disease ≥ 4 months were 22% and 39% (Group 1) and 9% and 0% (Group 2). The respective median time to treatment failure and overall survival were 3 and 6.9 months (Group 1) and 1.5 and 5.9 months (Group 2).

CONCLUSION

HAI oxaliplatin combined with capecitabine +/- bevacizumab was well-tolerated and was associated with favorable outcomes in selected patients.

Overview of precision oncology trials: challenges and opportunities

INTRODUCTION

In recent years, the therapeutic management of selected patients with cancer has shifted toward the 'precision medicine' approach based on patient's mechanisms of tumorigenesis, and their baseline characteristics and comorbidities. Complete tumor and cell-free DNA profiling using next-generation sequencing, proteomic and RNA analysis, and immune mechanisms should to be taken into consideration and accurate bioinformatic analysis is essential to optimize patient's treatment. Areas covered: The challenges and opportunities of conducting clinical trials in precision oncology are summarized. Expert commentary: Precision medicine has significantly changed the diagnostic and therapeutic landscape of cancer. Successful implementation of precision medicine requires translational and bioinformatics infrastructure to support optimization of treatment selection. Targeted therapy, immunotherapy, T-cell therapy alone or in combination with cytotoxic or other effective therapeutic strategies and innovative clinical trials with adaptive design should be offered to all patients. Data sharing and 'N-of-1' models hold the promise to optimize the treatment of individual patients and expedite drug approval for rare alterations and tumor types. Artificial intelligence will facilitate accurate utilization of sequencing data to perform algorithm analysis. Collaboration of healthcare providers with pharmaceutical and biotechnical companies, scientific organizations, and governmental regulatory agencies have a crucial role in curing cancer.

Abstract 1359: Somatic involution of pathogenic BRCA1 germline mutations

There is currently a wealth of data on the tumor genomic contexture from BRCA1/2 carriers, particularly breast and ovarian carcinomas. By contrast, little attention has as yet been paid to the genomic status of cancer-related normal tissues from these individuals. Here, we investigated the status of pathogenic BRCA1 germline mutations (GM) in breast (B) and gynecologic (GYN) tissues.

Methods: We examined 121 DNA samples (48 B; 36 GYN; 37 tumors) from an equal number of paraffin blocks obtained upon prophylactic or debulking surgery from 44 BRCA1/2 carriers (mean age 38 yrs, range 24-62; 43 BRCA1 carriers). Six women had never had cancer manifestation (CM). At the time of surgery, 32 were cancer-free but had received neo- or adjuvant chemotherapy, and 6 had concurrent cancer without prior treatment. Following multimethod DNA quality control, mutation validation and sample identity match to exclude false negatives, we interrogated GM presence in tissues in comparison to clinicopathologic data and tumor genotypes (60-gene panel; mean read depth over 800).

Results: In 19 samples from 13 BRCA1 carriers, including 13 normal B/GYN and 6 tumors, the germline mutation was present at frequencies lower than 5% (observed with the integrated genome viewer) up to 12%, or it was undetectable with Sanger sequencing and multiplex PCR. This condition, termed GM-loss, was present in 13 GYN, 12 of which in the histologically normal tube, and in only 3 B with fibrocystic disease (p=0.0210). It was also present in one ovarian thecoma but it was absent in usual or atypical hyperplasia in B. GM-loss was observed in 9/55 normal tissues from breast cancer and in 4/6 normal tissues from ovarian cancer patients, while it was absent in the normal tissues from women without CM (p=0.0002). GM-loss mostly affected the BRCA1 BRCT functional domain (p&lt;0.0001) and concerned large deletions (10/17 samples), small indels (5/32; 15.6%) and less so single-nucleotide substitutions (4/66; 6.0%; p&lt;0.0001). Normal tissue GM-loss was rather localized, e.g., in 10 patients with multiple samples it was present in only one B or fallopian tube. It was, however, related to the status of concurrent ovarian tumors in 3/6 cases. In the normal tube of these patients, next to the low-frequency GM a somatic pathogenic BRCA1 mutation was present at 25-41% allelic frequency; the same was observed in one breast tumor after neoadjuvant chemotherapy. Three of the replaced GMs were indels, two corresponded to the well-known BRCA1 p.Q1777fs, and all novel mutations were missense.

Conclusions: We observed BRCA1 GM-loss in normal tissues, breast and mostly fallopian tube, in about 30% of the carriers in the present cohort, all with previous or concurrent cancer. The phenomenon seems analogous to the GM reversion described in tumors but, as shown, it may also occur in the absence of prior treatment. Its origin and impact on cancer dynamics and therapeutic approaches seem worth further pursuing with functional studies.

Citation Format: Vassiliki Kotoula, Efterpi Demiri, Florentia Fostira, Eleni Vrettou, Kyriaki Papadopoulou, Ioannis Tikas, Konstantinos Papazisis, Thomas Zaramboukas, Asimina Asimaki-Vlachopoulou, Spyridon Miliaras, Elena Fountzilas, Ananias Ananiadis, Sofia Chrisafi, Christos Poulios, Ioannis Natsiopoulos, Aris Tsiftsoglou, George Fountzilas. Somatic involution of pathogenic BRCA1 germline mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1359.

Abstract P3-04-04: Germline and somatic mutation status in tissues from BRCA1/2 carriers

Background – aim: In carriers of BRCA1/2 pathogenic mutations (mut), it is expected that the germline mut is present in all tissues, particularly in normal; the somatic mut status in normal tissues from these patients is usually not addressed. We investigated the mut status in normal and tumor tissues in a real-life cohort of BRCA1/2 carriers who underwent prophylactic surgery.

Methods: All 53 women had known BRCA1/2 germline mut that had been assessed independently; 42 had previous cancer manifestation (PCM); all had prophylactic mastectomy; 22 had prophylactic hystero-salpingo-oophorectomy. By using a 60-gene NGS panel, we examined the mut status of 231 samples, 39 peripheral blood and 192 paraffin tissues (FFPE: 46 tumors, out of which 43 breast; 97 normal breast [NB]; 49 normal ovary and salpinx [NGYN]). Germline mut status was interrogated in tissues with the above panel, Sanger sequencing and a multiplex PCR protocol for large exonic deletions, along with extensive FFPE DNA quality control (QC) to exclude false negatives.

Results: Eight patients carried germline BRCA2 and 45 BRCA1 mut (29 in the BRCT-domain; 31 substitutions/indels). We identified somatic mut in 85% of the tumors and in 64% of the normal samples; mut were found significantly more often (p=0.003) and in higher numbers (p&lt;0.001) in NGYN than in NB. In NB and NGYN, top 3 genes with somatic mut were BRCA2 (28%), BRCA1 (17%), TP53 (7%). In tumors, somatic mut were most frequent in TP53 (49%; p&lt;0.001) and BRCA1 (38%; p=0.039). Among all tissue types, the 5 tumors post-neoadjuvant treatment had the highest and NB the lowest mut load (p=0.001). In NB and NGYN, mut load was not affected by PCM or BRCA1 mut domain but it was higher in BRCA1 vs. BRCA2 carriers (p=0.027) and in those with BRCA1 substitutions/indels vs. exon deleting and skipping mut (p&lt;0.001). In tumors, germline BRCA1 substitutions/indels were associated with higher mut load (p=0.014). We validated germline mut status in all blood samples and in 111 tissue samples that passed FFPE DNA QC from 40 patients. The germline mut was not found in 14 samples (4 breast tumors; 3 NB; 7 NGYN) from 10 (25%) patients, all BRCA1 carriers, 9 with germline mut in the BRCT-domain. The only non-BRCT domain germline mut that was lost in one breast tumor, p.V1234fs, was replaced by the R1751* (validated), again in the BRCT domain. In normal tissues, those with lost germline mut had significantly less somatic mut compared to those with preserved germline mut (p&lt;0.001).

Conclusions: In BRCA1/2 carriers, somatic mut in BRCA genes and TP53 are present in normal breast and GYN tissues, more frequently in the latter, and seem associated with the mutated gene and with the type of mut in the germline. The mut status of normal breast tissue does not seem to be affected by neoadjuvant chemotherapy for breast cancer. The observed BRCA1 germline mut loss, particularly in normal tissues, may be approached as a negative selection for the inherited mut; similarly to the described germline mut reversion after chemotherapy, tissues may react to deleterious effects of haploinsufficiency, which needs functional validation.

Citation Format: Kotoula V, Demiri E, Fostira F, Vrettou E, Papadopoulou K, Tikas I, Papazisis K, Zaramboukas T, Asimaki-Vlachopoulou A, Miliaras S, Fountzilas E, Ananiadis A, Chrisafi S, Poulios C, Natsiopoulos I, Tsiftsoglou A, Fountzilas G. Germline and somatic mutation status in tissues from BRCA1/2 carriers [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 P3-04-04.

Expanded access to investigational drugs: balancing patient safety with potential therapeutic benefits

Introduction:

Expanded access is the use of an investigational product by patients with serious medical conditions without participation in a clinical trial. It is a complicated process involving the collaboration of many parties and pharmaceutical companies. Ongoing efforts focus on accelerating expanded access procedures in the best interest of patients with cancer.

Areas covered:

We review the regulatory and ethical challenges encountered in efforts to optimize expanded access.

Expert opinion:

In the era of personalized medicine, patients may benefit from novel therapeutic agents that demonstrate encouraging results in early studies. However, drug approval is a lengthy and cumbersome procedure that might exceed the time frame of a life-threatening disease. Expanded access provides options to patients with unmet needs. It may provide informative safety and efficacy data to the manufacturers and the scientific and regulatory organizations.

Ongoing efforts are being made by global governmental and scientific committees, regulatory agencies, and patient organizations to address the ethical and regulatory issues and to optimize the expanded access process. Their goal is to expand access to promising novel drugs for individual patients and to accelerate the necessary procedures while preserving patient safety.

Genomic features of normal tissues from prophylactic surgery in BRCA1/2 mutation carriers

e13055

Background: Genomic alterations in normal tissues from pathogenic germline BRCA1/2 mutation (mut) carriers are as yet poorly described. We investigated the genomic status of normal breast (NB) and hystero-salpingo-oophorectomy (GYN) tissues removed upon prophylactic surgery in a real-life cohort of BRCA1/2 carriers. Methods: By using targeted NGS we examined the mut status of 220 samples (39 peripheral blood and 181 paraffin tissue) from 53 BRCA1/2 carriers who underwent prophylactic surgery, 42 with and 11 without prior cancer manifestation (PCM). We compared germline BRCA1/2 mut status with tumor, NB and GYN mut status. Results: Eight patients carried germline BRCA2 and 45 BRCA1 mut. Somatic mut were most frequent in BRCA2 (28%), BRCA1 (17%), TP53 (7%) among 136 NB and GYN samples; and, in TP53 (49%; p < 0.001) and BRCA1 (38%; p = 0.039) among 45 tumor samples. Among all tissue types, the 85 NB had the lowest mut load (p = 0.001). In NB and GYN, mut load was higher in BRCA1 vs. BRCA2 carriers (p = 0.027) and in those with BRCA1 substitutions/indels vs. exon deleting and skipping mut (p < 0.001). In tumors, only germline BRCA1 substitutions/indels were associated with higher mut load (p = 0.014). Preservation of germline mut in tissues was assessable in 84 samples from 26 patients. The germline mut was lost in 8 tumor and NB samples from 6 patients (23%) with PCM. Somatic deleterious mut in the BRCA1 BRCT-domain emerged in two such cases; the rest had combinations of TP53, MRE11A and NF1 mut. GYN samples from these patients retained the germline mut and presented the highest mut load among all examined samples (p < 0.001). Conclusions: Somatic mut in normal tissues from BRCA1/2 carriers are affected by the inherited mutated gene and by the type of the germline mut concerning BRCA1. Germline BRCA1 mut may be substituted by somatic mut in tumor and normal tissues, in an organ specific manner. Mutagenesis in tumors and normal tissues appear to be driven by different pathways. Our findings shed new light on the biological impact of BRCA1/2 mut in tissues.

Disease evolution and heterogeneity in bilateral breast cancer

Bilateral breast cancers (BBC) are currently treated as independent tumors arising in the same patient. Herein, we investigated whether BBC indeed evolve independently at the genomic level. We examined paired targeted next generation sequencing genotypes from 155 paraffin tumors corresponding to 76 BBC patients (75 women and one man; 52 concurrent and 24 metachronous), for coding mutations (amino acid changing, minor allele frequency <0.1%) and single nucleotide polymorphism (SNP) zygosity. Germline genotypes were available for 29 patients. Mutations were present in 80 tumors (54/76 patients; 71%), were mostly tumor-private (90%), more frequent in TP53 (19%), PIK3CA (14%), CDH1, GATA3, MLL3. TP53 mutations were more frequent in metachronous tumors (P<0.001); hormone receptor negative (P<0.001); with higher Ki-67 (P=0.002); and, in younger patients (P=0.01). Hypermutated tumors, all TP53 mutated, were diagnosed as the first incidence in 5 patients; their metachronous counterparts were mutation poor without TP53 involvement. Paired tumors shared common mutations at intratumoral frequency >20% in 10/54 comparable BBC (18.5%), 8/10 concurrent. SNP zygosity status was less preserved in metachronous, compared to concurrent disease. Pathogenic germline mutations were present in 10/29 patients, 9 in BRCA1 and one in TP53 (p.Phe341Val, first report in the germline). BBC demonstrated extensive inter- and intra-patient heterogeneity in the present thus far largest series of corresponding paired genotypes. The majority evolve independently and unpredictably, supporting current clinical practice. A considerable minority though, retains clonal origin and may be regarded as a distinct group for therapeutic interventions among concurrent BBC.

Abstract P2-07-02: Tumor infiltrating lymphocytes density and coding mutations effects on the outcome of operable triple negative breast cancer patients

Background-Aim: Neoantigens are considered to trigger host immune responses against tumors, which may be reflected by tumor infiltrating lymphocytes (TILs) density within the tumor stroma. High TILs levels have been associated with favorable triple-negative breast cancer (TNBC) patient outcome. Herein we evaluated the presence of coding mutations and TILs density with regard to outcome in a cohort of TNBC patients treated with anthracycline-based adjuvant chemotherapy.

Patients and Methods: Paraffin TNBC tissues from 242 patients treated in the context of four prospective clinical trials were histologically reviewed and submitted to massively parallel semiconductor sequencing with a custom panel targeting 57 breast cancer (BC)-related genes. Mutations (mut) were evaluated in 210 informative samples as missense/nonsense amino acid changing variants, with minor allele frequency &lt;1% in the case of single nucleotide polymorphisms. TILs density was morphologically evaluated as percent of the stromal area in 197 tumors; lymphocyte predominant (LP) BC tumors were called for TILs &gt;50%. Disease-free survival (DFS) was used as the endpoint for the present analysis.

Results: 426 Mut were observed for 40 genes in 147 TNBC patients (70%). Among mutated genes, ranging from 1 in 97 tumors up to &gt;10 in 8 tumors, the most frequently affected were TP53 (102 tumors, 69%) and PIK3CA (40 tumors, 27%). Intriguingly, mut rate (p=0.042) and number of mut genes (p=0.018) per tumor were inversely associated with TILs density. Nineteen tumors (10%) were LP-TNBC, carrying TP53 and PIK3CA mut as the only coding alterations in 10 and 3 cases, respectively. LP-TNBC patients did not experience any relapses during a follow-up period of 46-152 months (mean 66 months). For the 90% of non-LP-TNBC, the previously reported outcome benefit for 10% increments of TILs density was only demonstrated for tumors with 31-50% TILs. In non-LP-TNBC, upon adjustment for standard clinicopathological parameters, PIK3CA mut, TP53 mut and TILs density as a continuous variable, TP53 mut and nodal status independently conferred unfavorable DFS (HR=1.89, 95% CI 1.03-3.47, p=0.040 and HR=2.89, 95% CI 1.59-5.24, p=0.001, respectively). When continuous TILs density was added in the multivariate models in the entire cohort, 10% increments significantly predicted favorable DFS (HR=0.73, 95% CI 0.59-0.91, p=0.006), while high nodal status predicted unfavorable DFS (HR=2.75, 95% CI 1.51-4.99, p&lt;0.0001).

Conclusions: In the present study, tumors with higher TILs density, including LP-TNBC, were not characterized by multiple mutations or mutated genes with the panel tested. In TNBC, increasing TILs density is a strong favorable and high nodal status a strong unfavorable prognosticator. Importantly, LP-TNBC may be regarded as a distinct subgroup with excellent prognosis concerning 10% of TNBC. In non-LP-TNBC, TP53 mut and nodal status were significant unfavorable prognosticators. These data may suggest that the level of morphologically assessed TILs density does not necessarily correspond to the tumoral mutational load and merit validation in larger cohorts.

Citation Format: Kotoula V, Fountzilas E, Chatzopoulos K, Alexopoulou Z, Timotheadou E, Xanthakis I, Gogas H, Skondra M, Christodoulou C, Papadopoulou K, Chrisafi S, Koutras A, Xepapadakis G, Venizelos V, Efstratiou I, Patsea H, Kalogeras KT, Lakis S, Fountzilas G. Tumor infiltrating lymphocytes density and coding mutations effects on the outcome of operable triple negative breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-07-02.