B-cell infiltration is associated with survival outcomes following programmed cell death protein 1 inhibition in head and neck squamous cell carcinoma

BACKGROUND

Programmed cell death protein 1 (PD-1) axis blockade has become the mainstay in the treatment of recurrent and/or metastatic (R/M) head and neck squamous cell cancer (HNSCC). Programmed death-ligand 1 (PD-L1) is the only approved biomarker for patient selection; however, response rate is limited even among high expressors. Our primary objective was to investigate the association of immune cell-related biomarkers in the tumor and tumor microenvironment with PD-1 checkpoint inhibitors' outcomes in patients with R/M HNSCC.

PATIENTS AND METHODS

NCT03652142 was a prospective study in nivolumab-treated platinum-refractory R/M HNSCC, aiming to evaluate biomarkers of response to treatment. Tumor biopsies and blood samples were collected from 60 patients at baseline, post-treatment, and at progression. Immune cells in the tumor and stromal compartments were quantified by immunofluorescence using a five-protein panel (CD3, CD8, CD20, FoxP3, cytokeratin). Tertiary lymphoid structures (TLSs), PD-L1 expression, and peripheral blood immune cell composition were also evaluated for associations with outcome. Our findings were validated by gene set enrichment analysis (GSEA) messenger RNA in situ expression data from the same patients, for B-cell- and TLS-associated genes.

RESULTS

High pre-treatment density of stromal B cells was associated with prolonged progression-free survival (PFS) (P = 0.011). This result was validated by GSEA, as stromal enrichment with B-cell-associated genes showed association with response to nivolumab. PD-L1 positivity combined with high B-cell counts in stroma defined a subgroup with significantly longer PFS and overall survival (P = 0.013 and P = 0.0028, respectively).

CONCLUSIONS

Increased B cells in pre-treatment HNSCC biopsy samples correlate with prolonged benefit from PD-1-based immunotherapy and could further enhance the predictive value of PD-L1 expression.

Well-differentiated liposarcomas and dedifferentiated liposarcomas: Systemic treatment options for two sibling neoplasms

Well-differentiated liposarcomas (WDLPS) and dedifferentiated liposarcomas (DDLPS) account for 60 % of all liposarcomas, reflecting the heterogeneity of this type of sarcoma. Genetically, both types of liposarcomas are characterized by the amplification of MDM2 and CDK4 genes, which indicates an important molecular event with diagnostic and therapeutic relevance. In both localized WDLPS and DDLPS of the retroperitoneum and the extremities, between 25 % and 30 % of patients have local or distant recurrence, even when perioperatively treated, with clear margins present. The systemic treatment of WDLPS and DDLPS remains a challenge, with anthracyclines as the gold standard for first-line treatment. Several regimens have been tested with modest results regarding their efficacy. Herein we discuss the systemic treatment options for WDLPS and DDLPS and review their reported clinical efficacy results.

Immune checkpoint inhibitors in sarcomas: a systematic review

Sarcomas are tumors that originate from mesenchymal cells. The variety of sarcomas' response to chemotherapy and the wide range of prognosis reflect their heterogeneity. In order to improve the rates of response, the research has been orientated toward other forms of therapy, such as targeted therapies and immunotherapy or toward combinations of them. Immune checkpoint inhibitors (ICIs) have been the highlight of immunotherapy in the last decade. Although ICIs are already included in the guidelines of different malignancies, their clinical benefit in sarcomas is still under study. Alveolar soft part sarcomas, undifferentiated pleomorphic sarcomas and other subtypes of sarcoma with high presence of tertiary lymphoid structures tend to respond to ICIs, but further investigation is still needed. Furthermore, the search of predictive biomarkers to determine the type of sarcomas that are sensitive to ICIs is still very challenging. This review will focus on the results of clinical trials, which examine the effect of ICIs and their combination with chemotherapy, targeted therapies and other forms of immunotherapy in sarcomas.

Durvalumab with or without tremelimumab versus the EXTREME regimen as first-line treatment for recurrent or metastatic squamous cell carcinoma of the head and neck: KESTREL, a randomized, open-label, phase III study

BACKGROUND

Patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) have a poor prognosis. The phase III KESTREL study evaluated the efficacy of durvalumab [programmed death-ligand 1 (PD-L1) antibody] with or without tremelimumab [cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibody], versus the EXTREME regimen in patients with R/M HNSCC.

PATIENTS AND METHODS

Patients with HNSCC who had not received prior systemic treatment for R/M disease were randomized (2 : 1 : 1) to receive durvalumab 1500 mg every 4 weeks (Q4W) plus tremelimumab 75 mg Q4W (up to four doses), durvalumab monotherapy 1500 mg Q4W, or the EXTREME regimen (platinum, 5-fluorouracil, and cetuximab) until disease progression. Durvalumab efficacy, with or without tremelimumab, versus the EXTREME regimen in patients with PD-L1-high tumors and in all randomized patients was assessed. Safety was also assessed.

RESULTS

Durvalumab and durvalumab plus tremelimumab were not superior to EXTREME for overall survival (OS) in patients with PD-L1-high expression [median, 10.9 and 11.2 versus 10.9 months, respectively; hazard ratio (HR) = 0.96; 95% confidence interval (CI) 0.69-1.32; P = 0.787 and HR = 1.05; 95% CI 0.80-1.39, respectively]. Durvalumab and durvalumab plus tremelimumab prolonged duration of response versus EXTREME (49.3% and 48.1% versus 9.8% of patients remaining in response at 12 months), correlating with long-term OS for responding patients; however, median progression-free survival was longer with EXTREME (2.8 and 2.8 versus 5.4 months). Exploratory analyses suggested that subsequent immunotherapy use by 24.3% of patients in the EXTREME regimen arm contributed to the similar OS outcomes between arms. Grade 3/4 treatment-related adverse events (TRAEs) for durvalumab, durvalumab plus tremelimumab, and EXTREME were 8.9%, 19.1%, and 53.1%, respectively.

CONCLUSIONS

In patients with PD-L1-high expression, OS was comparable between durvalumab and the EXTREME regimen. Durvalumab alone, and with tremelimumab, demonstrated durable responses and reduced TRAEs versus the EXTREME regimen in R/M HNSCC.

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.

•

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

•

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

•

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

The DNA damage response network in the treatment of head and neck squamous cell carcinoma

BACKGROUND

We sought to determine whether DNA damage response (DDR)-related aberrations predict therapeutic benefit in cisplatin-treated head and neck squamous cell carcinoma (HNSCC) patients and how DDR pathways are modulated after treatment with olaparib alone or in combination with cisplatin or durvalumab.

PATIENTS AND METHODS

Oxidative stress, abasic sites and DDR-related parameters, including endogenous DNA damage, DNA repair mechanisms and apoptosis rates, were evaluated in HNSCC cell lines and peripheral blood mononuclear cells from 46 healthy controls (HC) and 70 HNSCC patients at baseline and following treatment with cisplatin-containing chemoradiation or nivolumab or enrolled in the OPHELIA phase II trial (NCT02882308; olaparib alone, olaparib plus cisplatin, olaparib plus durvalumab).

RESULTS

HNSCC patients at diagnosis exhibited deregulated DDR-related parameters and higher levels of oxidative stress and abasic sites compared with HC (all P < 0.05). Accordingly, nucleotide excision repair (NER; ERCC1, ERCC2/XPD, XPA, XPC) and base excision repair (APEX1, XRCC1) genes were downregulated in patients versus HC whereas double-strand breaks repair (MRE11A, RAD50, RAD51, XRCC2) and mismatch repair (MLH1, MSH2, MSH3) genes were overexpressed. Corresponding results were obtained in cell lines (all P < 0.001). Excellent correlations were observed between individual ex vivo and in vivo/therapeutic results, with cisplatin non-responders showing higher levels of endogenous DNA damage, augmented oxidative stress and abasic sites, increased NER capacities and reduced apoptosis than responders (all P < 0.05). Also, longer progression-free survival correlated with lower NER capacity (P = 0.037) and increased apoptosis (P = 0.029). Interestingly, treatment with olaparib-containing regimens results in the accumulation of cytotoxic DNA damage and exerts an extra antitumor effect by elevating oxidative stress (all P < 0.05). Nivolumab induced no significant changes in the DDR parameters examined.

CONCLUSIONS

Aberrations in DDR signals are implicated in the response to HNSCC chemotherapy and can be exploited as novel therapeutic targets, sensitive/effective non-invasive biomarkers as well as for the design of novel clinical trials.

Single-arm, open label prospective trial to assess prediction of the role of ERCC1/XPF complex in the response of advanced NSCLC patients to platinum-based chemotherapy

Background

Platinum-based therapy, combined or not with immune checkpoint inhibitors, represents a front-line choice for patients with non-small-cell lung cancer (NSCLC). Despite the improved outcomes in the last years for this malignancy, only a sub-group of patients have long-term benefit. Excision repair cross-complementation group 1 (ERCC1) has been considered a potential biomarker to predict the outcome of platinum-based chemotherapy in NSCLC. However, the ERCC1 gene is transcribed in four splice variants where the isoform 202 was described as the only one active and able to complex Xeroderma pigmentosum group F-complementing protein (XPF). Here, we prospectively investigated if the active form of ERCC1, as assessed by the ERCC1/XPF complex (ERCC1/XPF), could predict the sensitivity to platinum compounds.

Patients and methods

Prospectively enrolled, patients with advanced NSCLC treated with a first-line regimen containing platinum were centrally evaluated for ERCC1/XPF by a proximity ligation assay. Overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) were analyzed.

Results

The absence of the ERCC1/XPF in the tumor suggested a trend of worst outcomes in terms of both OS [hazard ratio (HR) 1.41, 95% confidence interval (CI) 0.67-2.94, P = 0.373] and PFS (HR 1.61, 95% CI 0.88-3.03, P = 0.123). ORR was marginally influenced in ERCC1/XPF-negative and -positive groups [odds ratio (stable disease + progressive disease versus complete response + partial response) 0.87, 95% CI 0.25-3.07, P = 0.832].

Conclusion

The lack of ERCC1/XPF complex in NSCLC tumor cells might delineate a group of patients with poor outcomes when treated with platinum compounds. ERCC1/XPF absence might well identify patients for whom a different therapeutic approach could be necessary.

•

This is the first study investigating the ERCC1/XPF complex as a platinum-based therapy response biomarker in NSCLC.

•

The lack of ERCC1/XPF complex might delineate a group of patients with poor outcomes when treated with platinum compounds.

•

ERCC1/XPF absence might identify tumors for whom a different therapeutic approach than platinum compounds could be necessary.

ABREAST: a prospective, real-world study on the effect of nab-paclitaxel treatment on clinical outcomes and quality of life of patients with metastatic breast cancer

PURPOSE

The efficacy of nab-paclitaxel in patients with metastatic breast cancer (MBC) has been demonstrated in randomized clinical trials. However, real-world evidence on effectiveness remains limited.

PATIENTS AND METHODS

The primary objective of this multicenter prospective study was to assess the overall response rate (ORR) of patients with MBC treated with nab-paclitaxel. Secondary objectives included progression-free survival (PFS), overall survival (OS) and quality of life, assessed with the Functional Assessment of Cancer Therapy-Breast (FACT-B) instrument.

RESULTS

Eligible patients (N = 150; 36% with de novo MBC presentation) with a median age of 64.5 years were enrolled (86% were ER+, 33.3% (50/150) were ≥ 70 years of age and 53% were treated in the third or later line of treatment). A median of 6 cycles were administered but 26% of patients required dose reduction due to toxicity. The ORR was 26.7% [95% confidence interval (CI) 19.6-33.7], the median PFS was 6.2 months (95% CI 5.2-7.3), and the median OS 21.1 months (95% CI 17.2-not estimable). There was no statistical significant difference in the median PFS of patients < and ≥ 70 years of age. The patients' baseline FACT-B total score remained unchanged. The serious and non-serious adverse event incidence rates were 13% and 48%, respectively.

CONCLUSIONS

This prospective study provides further evidence on quality of life, efficacy, and safety of nab-paclitaxel in patients with MBC and sheds more light in special subpopulations such as the elderly and those treated beyond the second line.

Abstract P4-08-13: Prognostic significance of CD8+ tumor-infiltrating lymphocytes (TILs) in patients with early breast cancer (EBC) treated with dose-dense sequential adjuvant chemotherapy (dds-CT). An observational study (ACTRN12616001043426)

Background - aim: Information on the prognostic role of cytotoxic CD8+ T cells in the era of modern adjuvant CT is limited. The primary objective of the present report is to assess the prognostic impact of CD8+ cells in patients with intermediate or high-risk EBC (T1-3N1-2M0) treated with dds-CT. Secondary endpoints are safety, disease-free survival (DFS) and overall survival (OS).

Patients and Methods: Patients (N=1,000) were treated with 4 cycles of Epirubicin, 75mg/m2, and Cyclophophamide, 600mg/m2 every 2 weeks followed by 4 cycles of Docetaxel (D), 100mg/m2 every 3 weeks with G-CSF support in all cycles. Trastuzumab was initiated concurrently with D and continued for a total of 1 year. Hormonal and radiation therapy were given post CT, as indicated. Formalin-fixed paraffin-embedded tumors were available for 642 patients (64.2%) and were centrally assessed for immunohistochemical subtypes (IHC4; N=526), stromal TILs density by morphology (N=636), as well as stromal and intratumoral cytotoxic CD8+ T cell numbers (N=554). TILs and CD8+ were assessed as continuous variables for associations and as 10% increments for outcome.

Results: In total, 901/1,000 pts (90.1%) completed 8 cycles of CT. Severe (gradeIII-IV) toxicitiesincludedneutropenia (5.6%), leucopenia (3.6%), lymphopenia (2.1%), hand-footsyndrome (2.1%), and hepatotoxicity (1.8%). Febrileneutropenia occurred in 1.6% of the patients. The 5-year DFS and OS rates were 89.5% and 93.1%, respectively. Luminal A tumors were classified in 26.2%, Luminal B in 35.2%, luminal HER2 in 9.5%; HER2-enriched in 7.2%; and, triple-negative (TNBC) in 21.9% of informative patients. Among subtypes, stromal TILs density was higher in HER2-enriched and TNBC (p&lt;0.001); intratumoral CD8+ values were higher in TNBC (p&lt;0.001); and, stromal CD8+ were higher in HER2-enriched (p=0.034). In all patients, TILs density and intratumoral CD8+ cell numbers were not associated with DFS and OS, while increased stromal CD8+ were marginally associated with prolonged DFS (HR=0.98, 95%CI 0.96-1.00, p=0.066).Adjusted for histological grade, menopausal, ER/PgR and nodal status, higher stromal CD8+ were associated with prolonged DFS (HR=0.98, 95% CI 0.96-1.00, p=0.043). In TNBC, higher stromal TILs density conferred prolonged DFS (HR=0.97, 95%CI 0.94-0.99, p=0.029), which retained its prognostic significance in multivariate analysis (HR=0.97, 95% CI 0.94-1.00, p=0.049).

Conclusions: In this study, dds-CT was well tolerated and active in patients with EBC. We confirm the presence of morphologically assessed higher TILs density, and of higher cytotoxic CD8+ T cell numbers in hormone receptor negative EBC, as well as the favorable prognostic impact of higher stromal TILs density in TNBC. In comparison to stromal TILs density, higher stromal CD8+ may confer favorable prognosis irrespectively of EBC subtype. Stromal CD8+ seems to be a marker worth further standardizing for reporting on immune cell infiltrates in EBC.

Citation Format: Kourea HP, Koletsa T, Kotoula V, Koliou G-A, Batistatou A, Pentheroudakis G, Arapantoni-Dadioti P, Zagouri F, Bobos M, Sotiropoulou M, Papoudou-Bai A, Chrisafi S, Efstratiou I, Aravantinos G, Nicolaou I, Gogas H, Visvikis A, Christodoulou C, Petraki C, Koutras A, Psyrri A, Pectasides D, Fountzilas G. Prognostic significance of CD8+ tumor-infiltrating lymphocytes (TILs) in patients with early breast cancer (EBC) treated with dose-dense sequential adjuvant chemotherapy (dds-CT). An observational study (ACTRN12616001043426) [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 P4-08-13.

Hellenic Alliance for Metastatic Breast Cancer: A Platform of Support, a Platform for Life

Background and context: W4O-Hellas (Women for Oncology-Hellas, a network of women professionals in oncology) and K.E.F.I. (an association of cancer patients) joined forces to create the “Hellenic Alliance for Metastatic Breast Cancer”, a project awarded through the SPARC initiative. The project is consisting among others, on creating, promoting and maintaining a Web-based platform of education, information, communication, advocacy and support for MBC patients in Greece. Aim: The aim of the platform is to provide education at patients and caregivers on various aspects concerning the disease, from diagnosis to palliative care, the available medical facilities, social services, benefits and allowances, clinical trials and issues concerning quality of life and psychological support. Strategy/Tactics: The development of an innovative Web-based tool was included in the “Hellenic Alliance for Metastatic Breast Cancer” project. It was overseen by a steering committee with W4O-Hellas and K.E.F.I. representatives, journalists, health economics advisors and state representatives. A support team was also created, to run and update the platform. Program/Policy process: The platform (“w4life.gr” reading “women for life” or “life for women with stage 4 disease”) is functional since June 2016 and was officially presented to the public on November 2016. The site´s structure is consisting of the main sections and an online forum. The sections contain information about the disease, the access to doctors, medical facilities, social services and patient groups, quality of life, nutrition and exercise issues, patient guidance and clinical trials available in Greece. The online forum is accessible 24 hours per day, and provides information and update about the network´s actions and upcoming seminars and forums. There is also a patient support direct line available on weekdays and access to other useful links. An online survey measuring quality of life data are running through the platform and the results will be presented in the near future. Since last year, a mobile application was also created aiming to an easier and user friendly access. Outcomes: By March 2018, the platform had 27,018 page views, 10,416 users who completed 13,020 sessions, with average session duration 2:23 minutes and bounce rate 74.54%. w4life received two awards from the Boussias-Health Care Business Awards-2017. The Gold Award, in the e-Health category digital applications for information and integrated patient care and a Silver Award for actions aimed at information, awareness, and prevention. What was learned: During the severe Hellenic socioeconomic crisis we have found that an alternative approach, as the above described, of dedicated oncologists toward their patients is needed, easy to use, helpful and sustainable and can provide important information and comfort to women with mBC their families and caregivers.

Evaluation of the impact of tumor HPV status on outcome in patients with locally advanced unresectable head and neck squamous cell carcinoma (HNSCC) receiving cisplatin, 5-fluorouracil with or without docetaxel: a subset analysis of EORTC 24971 study

Background

EORTC 24971 was a phase III trial demonstrating superiority of induction regimen TPF (docetaxel, cisplatin, 5-fluorouracil) over PF (cisplatin/5-fluorouracil), in terms of progression-free (PFS) and overall survival (OS) in locoregionally advanced unresectable head and neck squamous cell carcinomas. We conducted a retrospective analysis of prospectively collected data aiming to evaluate whether only HPV(-) patients (pts) benefit from adding docetaxel to PF, in which case deintensifying induction treatment in HPV(+) pts could be considered.

Patients and methods

Pretherapy tumor biopsies (blocks or slides) were assessed for high-risk HPV by p16 immunohistochemistry, PCR and quantitative PCR. HPV-DNA+ and/or p16+ tumors were subjected to in situ hybridization (ISH) and HPV E6 oncogene expression qRT-PCR analysis. Primary and secondary objectives were to evaluate the value of HPV/p16 status as predictive factor of treatment benefit in terms of PFS and OS. The predictive effect was analyzed based on the model used in the primary analysis of the study with the addition of a treatment by marker interaction term and tested at two-sided 5% significance level.

Results

Of 358, 119 pts had available tumor samples and 58 of them had oropharyngeal cancer. Median follow-up was 8.7 years. Sixteen of 119 (14%) evaluable samples were p16+ and 20 of 79 (25%) evaluable tumors were HPV-DNA+. 13 of 40 pts (33%) assessed with HPV-DNA ISH and 12 of 28 pts (43%) assessed for HPV E6 mRNA were positive. The preplanned analysis showed no statistical evidence of predictive value of HPV/p16 status for PFS (P = 0.287) or OS (P = 0.118).

Conclusions

The incidence of HPV positivity was low in the subset of EORTC 24971 pts analyzed. In this analysis only powered to detect a large treatment by marker interaction, there was no statistical evidence that treatment effect found overall was different in magnitude in HPV(+) or HPV(-) pts. These results do not justify selection of TPF versus PF according to HPV status.

Abstract P2-09-18: Multiplexed (18-Plex) measurement of protein targets in trastuzumab-treated patients using imaging mass cytometry

Introduction: Recent studies have shown that the molecular heterogeneity of HER2 intracellular (ICD) and extracellular (ECD) domains, as well as overall immune infiltration, are associated with response to adjuvant trastuzumab. Traditional strategies for in situ measurement in the tumor microenvironment allow the combination of up to 6 targets, limiting our capability for in-depth interrogation of tissues. Imaging Mass Cytometry (IMC) uses metal-conjugated antibodies to provide multidimensional, objective measurement of protein targets. We used this high-throughput multiplexing platform to perform an 18-plex assessment of HER2 ICD/ECD, cytotoxic T cell infiltration and other structural and signaling proteins in a cohort of patients treated with trastuzumab.

Methods: An antibody panel for detection of 18 targets (Pancytokeratin, HER2 ICD, HER2 ECD, CD8, vimentin, cytokeratin 7, beta-catenin, HER3, MET, EGFR, ERK 1-2, MEK 1-2, PTEN, PI3K p110 alpha, Akt, mTOR, Ki67 and Histone H3) was conjugated to unique metals for detection in an IMC instrument (Fluidigm). All assays were objectively standardized and validated using quantitative immunofluoresce (QIF). Finally, the IMC technique was validated against HER2 single marker assays by QIF. We used a collection of trastuzumab-treated patients from the HeCOG 10/05 trial (n=180), and identified a case:control series using 5-year recurrence events (n=19), which were matched to controls (n=41) by age and TNM stage. Formalin-fixed, paraffin embedded tissues in tissue microarray format were ablated in the IMC attachment to the CyTOF flow cytometer for simultaneous detection of markers. Image visualization was conducted using MCD Viewer (Fluidigm). Statistical analyses were performed using a range of platforms.

Results: Patients that recurred after adjuvant treatment with trastuzumab showed a decreased fraction of HER2 ECD pixels over threshold in a compartment determined by CK and HER2 ICD compared to cases without recurrence (p=0.057). After exclusion of the lowest HER2 expressers (that would have fallen below the threshold for positive by current HER2 assays), 5-year recurrence events where associated with reduced total ECD/ ICD ratio intensity in tumor (p=0.044). Patients below the median for total ECD/ICD ratio showed a trend for decreased benefit from trastuzumab (p=0.066). Levels of cytotoxic T cell infiltration, depicted by total CD8 intensity, were lower in patients with recurrences (p=0.05).

Conclusion: Objective measurement of highly multiplexed protein targets in routine, fixed breast cancer tissues shows that a decreased ratio of HER2 ECD/ ICD is associated with 5-year recurrence after trastuzumab treatment. This observation is consistent with our previous work using QIF but represents the first time this has been done on identical cell content (on a single tissue section). Additionally, on the same section we found that lower levels of overall cytotoxic T cell infiltration were associated with worse outcome. Further analysis of the multiplexed data, including both correlative and distance-based analyses are underway.

Citation Format: Carvajal-Hausdorf DE, Stanton KP, Patsenker J, Villarroel-Espindola F, Esch A, Montgomery RR, Psyrri A, Kalogeras KT, Kotoula V, Fountzilas G, Schalper KA, Kluger Y, Rimm DL. Multiplexed (18-Plex) measurement of protein targets in trastuzumab-treated patients using imaging mass cytometry [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 P2-09-18.

Cancer gene-panel testing identifies two loss-of-function alleles in PALB2 and PTEN

Synchronous loss-of-function mutations in the cancer predisposing genes, PTEN and PALB2 identified by multigene panel.

The promise of immunotherapy in head and neck squamous cell carcinoma

Squamous cell cancers of the head and neck (HNSCC) comprise a diverse group of malignancies that includes tobacco-related tumors in addition to an increasing number of human papillomavirus-associated cancers. Independently of cause, there is a growing body of evidence supporting that the immune system plays a pivotal role in HNSCC development, as tumor cells evade immunosurveillance by exploiting inhibitory checkpoint pathways that suppress anti-tumor T-cell responses. HNSCC cells have the ability to manipulate the immune system through a variety of different mechanisms, forcing it to promote tumor growth and spread. Over the last decade, discoveries in immunologic research resulted in increased understanding of complex interactions between HNSCC and the host immune system as well as T-cell regulatory mechanisms, promoting the development of a variety of novel immunotherapies. Following the availability of novel immunotherapeutic strategies, the challenge for clinicians is to understand how and in which clinical setting to use these agents in order to provide greater clinical benefit for patients. Combination of immunotherapies with standard treatment approaches also represents an evolving field of research. Herein, we provide a comprehensive review of immune escape mechanisms in HNSCC, as well as current immunotherapy approaches under investigation.

Prognostic role of pretreatment plasma fibrinogen in patients with solid tumors: A systematic review and meta-analysis

BACKGROUND

Plasma fibrinogen may be involved in several stages of cancer progression. Clinical studies have demonstrated that pretreatment plasma fibrinogen is associated with poor survival in various cancers. The aim of this meta-analysis was to examine the prognostic effect of circulating fibrinogen in solid tumors.

MATERIALS AND METHODS

We searched Medline, EMBASE, Cochrane Database of Systematic Reviews, and meeting proceedings to identify studies assessing the effect of pretreatment plasma fibrinogen on survival of cancer patients. Pooled multivariable-adjusted hazard ratios (HRs) for overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS) were estimated using random-effects models.

RESULTS

Data from 52 observational studies and 15,371 patients were summarized. An elevated baseline plasma fibrinogen was significantly associated with worse OS (pooled HR = 1.69; 95% CI = 1.48–1.92). The highest negative effect of elevated plasma fibrinogen on OS was demonstrated in renal cell carcinoma (pooled HR = 2.22), followed by head and neck cancer (pooled HR = 2.02), and colorectal cancer (pooled HR = 1.89). The adverse prognostic impact of high plasma fibrinogen remained in both non-metastatic and metastatic disease and patients of different ethnicity. Patients with high baseline fibrinogen had a significantly shorter DFS (pooled HR = 1.52) and CSS (pooled HR = 2.50).

CONCLUSIONS

An elevated pretreatment plasma fibrinogen significantly correlates with decreased survival in patients with solid tumors. Future clinical trials are warranted to determine whether plasma fibrinogen could be incorporated in cancer staging systems and whether fibrinogen-lowering therapies have a favorable effect on disease recurrence and mortality.

Abstract P3-07-06: Objective measurement of HER2 (ERBB2) intracellular and extracellular domain spatial co-localization stratifies benefit from adjuvant trastuzumab

Background: The ASCO/CAP guidelines consider chromogen-based immunohistochemistry (IHC) as the primary assay to determine HER2 status in breast cancer. U. S. Food and Drugs Administration (FDA) approved HER2 antibody assays target the protein's intracellular domain (ICD). Studies suggest that quantitative, domain-specific measurement of HER2 might predict benefit from trastuzumab therapy, further classifying traditional HER2-positive breast cancer. Here we define a method of simultaneous, objective measurement of HER2 ICD and extracellular (ECD) domains, and determine its effect on trastuzumab benefit in the adjuvant setting.

Methods: We measured co-expression of HER2 ICD and ECD using a proximity ligation assay (PLA) and quantitative immunofluorescence (QIF) in a HER2 standardization tissue microarray (TMA) with CLIA-lab defined HER2 status. Previously validated, standardized HER2 antibodies were used to detect ICD and ECD (CB11 and SP3, respectively). We determined the relationship between HER2 PLA scores, HER2 clinical status and domain-specific scores. Finally, we measured HER2 ICD/ECD PLA in 180 patients from a clinical trial of adjuvant chemotherapy followed by trastuzumab (HeCOG 10/05). Median cut-point was used to stratify patients according to HER2 PLA scores. Cut-points for HER2 ICD and ECD were obtained using Joinpoint software. All statistical tests were two-sided.

Results: In the standardization TMA, HER2 PLA levels were associated to HER2 CLIA status (P&lt;0.0001). There was a good correlation between HER2 PLA scores and HER2 ICD and ECD (R2=0.57 and R2=0.54, respectively). In trastuzumab-treated patients from HeCOG 10/05, a similarly good correlation was observed between HER2 PLA scores and HER2 ICD and ECD (R2=0.41 and R2=0.3, respectively). In univariate analysis, HER2 PLA-low status was associated with ER-positive status (P=0.005). There was no association with age, histological grade, tumor size, lymph node status and TNM stage. Although all tumors were HER2-positive, HER2 PLA-high status was significantly associated with longer 5-year disease-free survival (DFS) (log-rank P=0.036, HR=0.32, 95% CI: 0.132-0.935). HER2 PLA status was superior to ICD status (log-rank P=0.67) and numerically comparable to ECD status (log-rank P=0.049, HR=0.31, 95% CI: 0.144-0.997) to predict benefit from adjuvant trastuzumab, as previously published by our group. HER2 PLA-high status was independent predictor of better outcome in a Cox proportional hazards model including age, histological grade, ER status, tumor size, lymph node status and TNM stage.

Discussion: Using an objective, quantitative HER2 assay for synchronous, domain-specific measurement, we stratified benefit from adjuvant trastuzumab treatment in patients from a prospective cohort. Our results further support the concept that benefit from HER2 ECD-targeted therapies might be modulated by the presence of truncated HER2 protein variants and that tyrosine kinase inhibitors (ICD-directed) may be advantageous for a subset of HER2-positive patients. Furthermore, this technique that uses two antibodies has the potential to increase both sensitivity and specificity of the IHC assay to predict response to HER2 pathway inhibitors.

Citation Format: Carvajal-Hausdorf DE, Toki M, Schalper KA, Pusztai L, Psyrri A, Kalogeras KT, Kotoula V, Fountzilas G, Rimm DL. Objective measurement of HER2 (ERBB2) intracellular and extracellular domain spatial co-localization stratifies benefit from adjuvant trastuzumab. [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 P3-07-06.