Circulating tumor DNA in advanced solid tumors: Clinical relevance and future directions.

The application of genomic profiling assays using plasma circulating tumor DNA (ctDNA) is rapidly evolving in the management of patients with advanced solid tumors. Diverse plasma ctDNA technologies in both commercial and academic laboratories are in routine or emerging use. The increasing integration of such testing to inform treatment decision making by oncology clinicians has complexities and challenges but holds significant potential to substantially improve patient outcomes. In this review, the authors discuss the current role of plasma ctDNA assays in oncology care and provide an overview of ongoing research that may inform real-world clinical applications in the near future.

The emerging role of immunotherapy in gastric and esophageal adenocarcinoma.

Gastric and esophageal adenocarcinomas are aggressive malignancies. Systemic therapy for these tumors relies primarily on cytotoxic chemotherapy but outcomes remain poor. In recent years, immunotherapy has emerged as a new, promising therapeutic approach for a variety of solid tumors. Characterization of gastroesophageal cancers has revealed genomic and immune features of these tumors that may predict response to immunotherapy. Indeed, preliminary results from the initial trials of immune checkpoint inhibitors have been encouraging, with objective response rates of 20% in heavily pretreated patient populations. Based on these results, additional trials of single-agent checkpoint inhibitors as well as combinations with chemotherapy and targeted therapies are currently ongoing. Further work to identify predictive biomarkers will be crucial for the successful implementation of immunotherapy.

Spontaneous Regression of Hepatocellular Carcinoma with Multiple Lung Metastases: A Case Report and Review of the Literature.

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare event. Here we present a case of spontaneous regression of metastatic HCC. A 53-year-old man with hepatitis C and alcoholic cirrhosis was found to have a large liver mass consistent with HCC based on its radiographic features. Imaging also revealed left portal and hepatic vein thrombosis, as well as multiple lung nodules concerning for metastases. Approximately 2 months after the initial diagnosis, both the primary liver lesion and the lung metastases decreased in size and eventually resolved without any intervention. Thereafter, the left hepatic vein thrombus progressed into the inferior vena cava and the right atrium, and the patient died due to right heart failure. In this case report and literature review, we discuss the potential mechanisms for and review the literature on spontaneous regression of metastatic HCC.

Quantitative assessment shows loss of antigenic epitopes as a function of pre-analytic variables.

Pre-analytic variables, specifically cold ischemic time, have been implicated as key variables in the measurement of proteins by immunohistochemistry. To determine the significance and magnitude of antigenic loss due to pre-analytic variables, we have compared protein antigenicity in core needle biopsies, with essentially no cold ischemic time, with that in routinely processed tumor resection specimens. Two cohorts of matched core needle biopsies and tumor resections were collected with 20 matched pairs and 14 matched pairs, respectively. Both series were analyzed by quantitative immunofluorescence using the AQUA® method. Epitopes phospho-ERK, total ERK, phospho-AKT, total AKT, phospho-S6K1, total S6K1, estrogen receptor (ER), Ki67, cytokeratin and GAPDH were assessed. Detection levels for all phospho-epitopes were significantly decreased in tumor resections compared with biopsies while no significant change was seen in the corresponding total proteins. Of the other four proteins examined, ER and cytokeratin showed significant loss of antigenicity. This data suggest that measurement of phospho-protein antigenicity in formalin-fixed tissue by immunological methods is dramatically affected by pre-analytic variables. This study suggests that core needle biopsies are more accurate for assessment of tissue biomarkers.

Phase II study of pembrolizumab in refractory esophageal cancer with correlates of response and survival.

BACKGROUND: Immune checkpoint inhibitors have revolutionized cancer treatment, but the benefits in refractory patients with esophageal cancer have been modest. Predictors of response as well as new targets for novel therapeutic combinations are needed. In this phase 2 clinical trial, we tested single-agent pembrolizumab in patients with advanced esophageal cancer, who received at least one prior line of therapy. METHODS: Pembrolizumab 200 mg every 3 weeks was tested in 49 patients with refractory esophageal cancer: 39 with adenocarcinoma and 10 with esophageal squamous cell carcinoma. Major endpoints were radiological response by Immune-related Response Evaluation Criteria In Solid Tumors and survival. Tumor samples were evaluated for programmed cell death ligand 1 (PD-L1) expression, tumor mutational burden (TMB), and immune contexture by both NanoString mRNA expression analysis and flow cytometry. Peripheral blood mononuclear cells and a panel of circulating chemokines were also analyzed. RESULTS: The overall response rate (ORR) was 8% (4 of 49 patients; 95% CI 2.3% to 19.6%). Median overall survival (OS) was 5.8 months (95% CI 4.0 to 9.5). ORR and OS were not associated with histology. For PD-L1-positive patients, ORR was 13.3% (95% CI 1.7% to 40.5%) and median OS was 7.9 months (95% CI 4.7 to 15.5). A trend toward improved OS was observed in seven patients with a TMB ≥10 mut/Mb (p=0.086). Tumors with a PD-L1 Combined Positive Score ≥1 showed enrichment of LAG3 (p=0.005) and IDO1 (p=0.04) gene expression. Baseline levels of circulating CXCL10, interleukin 2 (IL2) receptor α (IL2RA) and IL6 were associated with survival: CXCL10 favorably, (HR 0.37, p=0.002 (progression-free survival); HR 0.55, p=0.018 (OS)); IL2RA and IL6 unfavorably (HR 1.57, p=0.020 for IL6 (OS); HR 2.36, p=0.025 for IL2RA (OS)). CONCLUSIONS: Pembrolizumab monotherapy was modestly effective in refractory esophageal cancer. Circulating CXCL10 at baseline appeared to be a robust predictor of response. Other T cell exhaustion markers are upregulated in PD-L1-positive patients, suggesting that immunotherapy combinations such as anti-LAG3/programmed cell death protein 1 (PD-1) or anti-IDO1/PD-1 may be of promise in refractory esophageal cancer.

Evaluation of six CTLA-4 polymorphisms in high-risk melanoma patients receiving adjuvant interferon therapy in the He13A/98 multicenter trial.

PURPOSE: Interferon is approved for adjuvant treatment of patients with stage IIb/III melanoma. The toxicity and uncertainty regarding survival benefits of interferon have qualified its acceptance, despite significant durable relapse prevention in a fraction of patients. Predictive biomarkers that would enable selection of patients for therapy would have a large impact upon clinical practice. Specific CTLA-4 polymorphisms have previously shown an association with response to CTLA-4 blockade in patients with metastatic melanoma and the development of autoimmunity. EXPERIMENTAL DESIGN: 286 melanoma patients and 288 healthy controls were genotyped for six CTLA-4 polymorphisms previously suggested to be important (AG 49, CT 318, CT 60, JO 27, JO30 and JO 31). Specific allele frequencies were compared between the healthy and patient populations, as well as presence or absence of these in relation to recurrence. Alleles related to autoimmune disease were also investigated. RESULTS: No significant differences were found between the distributions of CTLA-4 polymorphisms in the melanoma population compared with healthy controls. Relapse free survival (RFS) and overall survival (OS) did not differ significantly between patients with the alleles represented by these polymorphisms. No correlation between autoimmunity and specific alleles was shown. The six polymorphisms evaluated where strongly associated (Fisher's exact p-values < 0.001 for all associations) and significant linkage disequilibrium among these was indicated. CONCLUSION: No polymorphisms of CTLA-4 defined by the SNPs studied were correlated with improved RFS, OS, or autoimmunity in this high-risk group of melanoma patients.

Prognostic Biomarkers in Early-stage Gastric Adenocarcinoma Treated With Adjuvant Chemoradiotherapy.

BACKGROUND/AIM: Early-stage gastric cancer has a high risk of recurrence, despite trimodality therapy with surgery, chemotherapy and radiation. To improve patient selection for adjuvant chemoradiotherapy, we evaluated the prognostic significance of immunohistochemical and genetic biomarkers in patients with resected gastric adenocarcinoma. PATIENTS AND METHODS: Tumors from 119 patients were subjected to immunohistochemistry for 12 protein biomarkers, as well as next-generation sequencing. Clinical and biomarker data were available for 91 patients. RESULTS: EBV-positive tumors and tumors with mutations had higher intratumoral CD8 tumor-infiltrating lymphocyte density (p=0.009 and p=0.017, respectively). PIK3CA mutations were correlated with VEGFA overexpression (p=0.042), while KRAS mutations and HER2 expression were mutually exclusive (p=0.036). PTEN expression univariately confirmed longer overall survival (HR=0.27; p=0.046), while there was a trend between the presence of KRAS mutations and inferior disease-free and overall survival. CONCLUSION: PTEN protein expression and KRAS mutations may predict disease outcome in early-stage gastric cancer. These results need to be further validated in larger cohorts.

Combination chemotherapy with docetaxel, vinorelbine and estramustine phosphate in metastatic androgen-resistant prostate cancer: a single institution experience.

UNLABELLED: The aim of this study was to evaluate the activity and toxicity of docetaxel, vinorelbine and oral estramustine in androgen-resistant prostate cancer (ARPC). PATIENTS AND METHODS: Fifty-two eligible patients were treated with docetaxel at 30 mg/m2 (day 1 and 8), vinorelbine at 20 mg/m2 (day 1 and 8), and oral estramustine of 280 mg p.o. (daily on days 1 to 7) every 3 weeks for 12 cycles. Patients with osseous metastases received zoledronic acid of 4 mg every 3 weeks. Low molecular weight heparin was administered on a prophylaxis basis to all patients. RESULTS: A prostate-specific antigen (PSA) response > or = 50% from baseline was obtained in 29 (56%; 95% confidence interval [CI], 42-70%) patients. Objective responses among the 25 patients with measurable disease were observed in 48% (95% CI, 27-69%), including 1 patient with complete response (CR) and 11 patients with partial response (PR). Patients with extraosseous only, skeletal only, and extraosseous and skeletal metastases showed different PSA responses (87% vs. 44% vs. 59%, respectively, p = 0.094). Furthermore, patients with soft tissue disease only showed insignificantly better PSA response than those with skeletal metastases (response rate: 87% vs. 50%, p = 0.064). The median progression-free survival was 7.6 months (95% CI, 6.7-8.4 months) and the median overall survival was 18.2 months (95% CI, 15.5-20.8 months). The only parameters which were found to have an impact on survival were the extent of disease and the baseline levels of PSA. Toxicity was generally mild except for myelotoxicity. Neutropenia grade 3/4 was recorded in 33% of patients and 6% experienced febrile neutropenia. Anemia and thrombocytopenia grade 3 or 4 were not a problem. Three patients (6%) developed grade 3 sensory neuropathy and 2 patients (4%) developed grade 3 fatigue. Edema grade 3 occurred in 1 (2%) patient and thromboembolism grade 3 occurred in 2 (4%) patients. CONCLUSION: The combination of docetaxel, vinorelbine and oral estramustine is a well-tolerated regimen with high biochemical and objective response rates in patients with ARPC.

Carboplatin and paclitaxel in metastatic or recurrent cervical cancer.

OBJECTIVES: The purpose of this study was to evaluate the activity and toxicity of carboplatin and paclitaxel combination in advanced or recurrent carcinoma of the cervix. METHODS: Fifty-one eligible patients with measurable advanced or recurrent cervical carcinoma were treated with carboplatin (area under the curve, 5) and paclitaxel 175 mg/m every 3 weeks for 6 to 9 cycles or until disease progression or unacceptable toxicity. RESULTS: Eight complete (16%) and 19 partial responses (37%) occurred, for an overall response rate (RR) of 53% (95% confidence interval [CI], 39%-67%). The median progression-free survival was 6 months (95% CI, 5.4-6.5 months), and the median overall survival was 13 months (95% CI, 11.4-14.5 months). The RR was higher in patients with disease outside a previously irradiated site compared with those with disease in a previously irradiated field (68% vs 30%) (P = 0.011). Patients previously treated with chemoradiation had an RR of 28%, whereas in those previously treated with radiotherapy alone, the RR was 68% (P = 0.023). There was no statistically significant difference between histology and response to therapy. Patients with performance status of 0 or 1 had a higher RR than those with worse performance status. Toxicity was generally mild except for myelotoxicity. Neutropenia grade 3/4 was recorded in 44% of patients, and 6% experienced febrile neutropenia. Twenty-two percent of patients experienced anemia grade 3-4, whereas 14% had thrombocytopenia grade 3-4. Three patients (6%) developed grade 3 sensory neuropathy. CONCLUSION: The combination of carboplatin and paclitaxel seems to have activity in advanced or recurrent cervical carcinoma with an acceptable toxicity profile.

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.

A Comprehensive PDX Gastric Cancer Collection Captures Cancer Cell-Intrinsic Transcriptional MSI Traits.

Gastric cancer is the world's third leading cause of cancer mortality. In spite of significant therapeutic improvements, the clinical outcome for patients with advanced gastric cancer is poor; thus, the identification and validation of novel targets is extremely important from a clinical point of view. We generated a wide, multilevel platform of gastric cancer models, comprising 100 patient-derived xenografts (PDX), primary cell lines, and organoids. Samples were classified according to their histology, microsatellite stability, Epstein-Barr virus status, and molecular profile. This PDX platform is the widest in an academic institution, and it includes all the gastric cancer histologic and molecular types identified by The Cancer Genome Atlas. PDX histopathologic features were consistent with those of patients' primary tumors and were maintained throughout passages in mice. Factors modulating grafting rate were histology, TNM stage, copy number gain of tyrosine kinases/KRAS genes, and microsatellite stability status. PDX and PDX-derived cells/organoids demonstrated potential usefulness to study targeted therapy response. Finally, PDX transcriptomic analysis identified a cancer cell-intrinsic microsatellite instability (MSI) signature, which was efficiently exported to gastric cancer, allowing the identification, among microsatellite stable (MSS) patients, of a subset of MSI-like tumors with common molecular aspects and significant better prognosis. In conclusion, we generated a wide gastric cancer PDX platform, whose exploitation will help identify and validate novel "druggable" targets and optimize therapeutic strategies. Moreover, transcriptomic analysis of gastric cancer PDXs allowed the identification of a cancer cell-intrinsic MSI signature, recognizing a subset of MSS patients with MSI transcriptional traits, endowed with better prognosis. SIGNIFICANCE: This study reports a multilevel platform of gastric cancer PDXs and identifies a MSI gastric signature that could contribute to the advancement of precision medicine in gastric cancer.

Combination chemotherapy with carboplatin, paclitaxel and pegylated liposomal doxorubicin for advanced or recurrent carcinosarcoma of the uterus: clinical experience of a single institution.

OBJECTIVES: The purpose of this study was to evaluate the activity and toxicity of carboplatin, paclitaxel and pegylated liposomal doxorubicin combination in advanced or recurrent of the uterine carcinosarcoma. METHODS: Twenty-nine eligible patients with measurable disease were treated with carboplatin [area under the curve (AUC) 5], paclitaxel 175 mg/m(2) and pegylated liposomal doxorubicin 25 mg/m(2) every 3 weeks for 6-8 cycles. RESULTS: There were 10 complete responses (CRs) (34%) and 8 partial responses (PRs) (28%) for an overall response rate (RR) of 62% (95% confidence interval [CI], 43-81%). The median progression-free survival (PFS) was 8.2 months (95% CI, 4.1-12.2 months) and the median overall survival (OS) was 16.4 months (95% CI, 14.7-18.0 months). There was no statistically significant difference between histology and response to therapy. Patients with PS of 0 or 1 had a higher RR than those with worst PS. Toxicity was generally mild except for myelotoxicity. Neutropenia grade 3/4 was recorded in 52% of patients and 10% experienced febrile neutropenia. Anemia grade 3 or 4 developed in 27% of patients and thrombocytopenia grade 3 or 4 in 31% of patients. Three patients (10%) developed grade 3 sensory neuropathy and only 2 patients (8%) grade 3 palmar-plantar erythrodysesthesias. No treatment-related deaths were recorded in our series. CONCLUSION: The combination of carboplatin, paclitaxel and pegylated liposomal doxorubicin appears to have activity in advanced, persistent or recurrent endometrial carcinosarcoma with an acceptable toxicity profile.

Genomic Heterogeneity as a Barrier to Precision Medicine in Gastroesophageal Adenocarcinoma.

Gastroesophageal adenocarcinoma (GEA) is a lethal disease where targeted therapies, even when guided by genomic biomarkers, have had limited efficacy. A potential reason for the failure of such therapies is that genomic profiling results could commonly differ between the primary and metastatic tumors. To evaluate genomic heterogeneity, we sequenced paired primary GEA and synchronous metastatic lesions across multiple cohorts, finding extensive differences in genomic alterations, including discrepancies in potentially clinically relevant alterations. Multiregion sequencing showed significant discrepancy within the primary tumor (PT) and between the PT and disseminated disease, with oncogene amplification profiles commonly discordant. In addition, a pilot analysis of cell-free DNA (cfDNA) sequencing demonstrated the feasibility of detecting genomic amplifications not detected in PT sampling. Lastly, we profiled paired primary tumors, metastatic tumors, and cfDNA from patients enrolled in the personalized antibodies for GEA (PANGEA) trial of targeted therapies in GEA and found that genomic biomarkers were recurrently discrepant between the PT and untreated metastases. Divergent primary and metastatic tissue profiling led to treatment reassignment in 32% (9/28) of patients. In discordant primary and metastatic lesions, we found 87.5% concordance for targetable alterations in metastatic tissue and cfDNA, suggesting the potential for cfDNA profiling to enhance selection of therapy.Significance: We demonstrate frequent baseline heterogeneity in targetable genomic alterations in GEA, indicating that current tissue sampling practices for biomarker testing do not effectively guide precision medicine in this disease and that routine profiling of metastatic lesions and/or cfDNA should be systematically evaluated. Cancer Discov; 8(1); 37-48. ©2017 AACR.See related commentary by Sundar and Tan, p. 14See related article by Janjigian et al., p. 49This article is highlighted in the In This Issue feature, p. 1.

Sequencing Treatment in BRAFV600 Mutant Melanoma: Anti-PD-1 Before and After BRAF Inhibition.

Novel agents targeting immune checkpoint molecules or mutated BRAF are active therapeutic options for patients with BRAF-mutant melanoma. However, the most effective first-line treatment and the optimal sequencing of these agents have not been well characterized. To explore this, we retrospectively assessed 114 patients from 4 centers with advanced, BRAF-mutant melanoma who received anti-programmed cell death-1 (PD-1)/PD-L1 antibodies. We evaluated clinical outcomes, including objective response rate (ORR), overall survival (OS), and progression-free survival (PFS) to initial and subsequent therapies in patients that received anti-PD-1 first (n=56) versus those that received BRAF±MEK inhibitors (BRAFi) first (n=58). Median OS was similar between these groups (27.5 vs. 40.3 mo, P=0.71). Patients who progressed on anti-PD-1 during the study timeframe had worse outcomes after starting subsequent BRAFi than those who had not received prior anti-PD-1 (median PFS 5 vs. 7.4 mo, median OS 10.6 vs. 40.3 mo). Similarly, patients who previously progressed on BRAFi had seemingly inferior outcomes after starting anti-PD-1 compared with those without prior BRAFi, including ORR (25% vs. 41%), median PFS (2.8 vs. 10.6 mo) and median OS (8.2 vs. 27.6 mo). Notably, patients who benefited >6 months from BRAFi had superior ORR to subsequent anti-PD-1 compared with those with more rapid progression (<6 mo) on BRAFi (34% vs. 15%, P=0.04). We conclude that either BRAFi or anti-PD-1 may be effective regardless of treatment sequence in patients with BRAF-mutant melanoma, but clinical outcomes to front-line therapy are superior. In addition, we suggest a shared "responder phenotype" between BRAFi and anti-PD-1.

CDK4/6 or MAPK blockade enhances efficacy of EGFR inhibition in oesophageal squamous cell carcinoma.

Oesophageal squamous cell carcinoma is a deadly disease where systemic therapy has relied upon empiric chemotherapy despite the presence of genomic alterations pointing to candidate therapeutic targets, including recurrent amplification of the gene encoding receptor tyrosine kinase epidermal growth factor receptor (EGFR). Here, we demonstrate that EGFR-targeting small-molecule inhibitors have efficacy in EGFR-amplified oesophageal squamous cell carcinoma (ESCC), but may become quickly ineffective. Resistance can occur following the emergence of epithelial-mesenchymal transition and by reactivation of the mitogen-activated protein kinase (MAPK) pathway following EGFR blockade. We demonstrate that blockade of this rebound activation with MEK (mitogen-activated protein kinase kinase) inhibition enhances EGFR inhibitor-induced apoptosis and cell cycle arrest, and delays resistance to EGFR monotherapy. Furthermore, genomic profiling shows that cell cycle regulators are altered in the majority of EGFR-amplified tumours and a combination of cyclin-dependent kinase 4/6 (CDK4/6) and EGFR inhibitors prevents the emergence of resistance in vitro and in vivo. These data suggest that upfront combination strategies targeting EGFR amplification, guided by adaptive pathway reactivation or by co-occurring genomic alterations, should be tested clinically.

Genomic Alterations and Targeted Therapy in Gastric and Esophageal Adenocarcinoma.

PURPOSE: Gastric and esophageal adenocarcinomas are common and aggressive malignancies. Systemic therapy for these tumors is based primarily on cytotoxic chemotherapy, but outcomes remain poor. Precision medicine, where treatments are tailored to specific molecular abnormalities of tumors, holds great promise for improving outcomes in this disease. METHODS: A search was performed in PubMed to identify studies that have characterized the molecular basis of gastric and esophageal adenocarcinoma, as well as clinical trials exploring targeted therapies in this disease. FINDINGS: Recent genomic studies have identified potentially targetable genomic alterations in gastroesophageal adenocarcinoma. Specifically, The Cancer Genome Atlas study defined 4 subgroups of gastric cancer, each harboring distinct genomic features. However, development of targeted therapies for gastroesophageal cancer has been challenging. The only biomarker-driven therapy in clinical practice, trastuzumab for the ~15% of patients with human epidermal growth factor receptor 2-positive disease, is modestly effective, extending median overall survival by 2.7 months. Clinical trials of other targeted therapies, including epidermal growth factor receptor, fibroblast growth factor receptor 2, and MET inhibitors, have had disappointing results so far. IMPLICATIONS: The availability of genomic tools provides an unprecedented opportunity to develop new rational therapeutic strategies. New trial designs of targeted therapies in biomarker-selected patient populations have the potential to improve outcomes in this lethal disease. As these clinical trials are being developed, it is increasingly important to incorporate correlative studies that will allow us to identify biomarkers of response or resistance to targeted therapies.

ERBB2 emerges as a new target for colorectal cancer.

ERBB2 mutations and amplifications are present in 7% of colorectal cancers. The presence of these alterations may be a marker of resistance to anti-EGFR therapy and, more importantly, could help identify patients who would benefit from ERBB2-directed therapy.

Prognostic biomarkers in phase II trial of cetuximab-containing induction and chemoradiation in resectable HNSCC: Eastern cooperative oncology group E2303.

PURPOSE: We sought to evaluate the correlation between tissue biomarker expression (using standardized, quantitative immunofluorescence) and clinical outcome in the E2303 trial. EXPERIMENTAL DESIGN: Sixty-three eligible patients with operable stage III/IV head and neck squamous cell cancer (HNSCC) participated in the Eastern Cooperative Oncology Group (ECOG) 2303 phase II trial of induction chemotherapy with weekly cetuximab, paclitaxel, and carboplatin followed by chemoradiation with the same regimen. A tissue microarray (TMA) was constructed and EGF receptor (EGFR), ERK1/2, Met, Akt, STAT3, ß-catenin, E-cadherin, EGFR Variant III, insulin-like growth factor-1 receptor, NF-κB, p53, PI3Kp85, PI3Kp110a, PTEN, NRAS, and pRb protein expression levels were assessed using automated quantitative protein analysis (AQUA). For each dichotomized biomarker, overall survival (OS), progression-free survival (PFS), and event-free survival (EFS) were estimated by the Kaplan-Meier method and compared using log-rank tests. Multivariable Cox proportional hazards models were used to estimate HRs and test for significance. RESULTS: Forty-two of 63 patients with TMA data on at least one biomarker were included in the biomarker analysis. Tumor extracellular signal-regulated kinase (ERK)1/2 levels were significantly associated with PFS [HR (low/high), 3.29; P = 0.026] and OS [HR (low/high), 4.34; P = 0.008]. On multivariable Cox regression analysis, ERK1/2 remained significantly associated with OS (P = 0.024) and PFS (P = 0.022) after controlling for primary site (oropharynx vs. non-oropharynx) and disease stage (III vs. IV), respectively. Clustering analysis revealed that clusters indicative of activated RAS/MAPK/ERK and/or PI3K/Akt pathways were associated with inferior OS and/or PFS and maintained significance in multivariable analysis. CONCLUSIONS: These results implicate PI3K/Akt and RAS/MAPK/ERK pathways in resistance to cetuximab-containing chemoradiation in HNSCC. Large prospective studies are required to validate these results.

Markers of epithelial to mesenchymal transition in association with survival in head and neck squamous cell carcinoma (HNSCC).

BACKGROUND: Elucidating the molecular phenotype of cancers with high metastatic potential will facilitate the development of novel therapeutic approaches to the disease. Gene expression profiles link epithelial to mesenchymal transition (EMT) phenotype with high-risk HNSCC. We sought to determine the role of protein biomarkers of EMT in head and neck squamous carcinoma (HNSC) prognosis. METHODS: Protein expression analysis of EGFR, ß-catenin and E-cadherin was performed on a cohort of 102 patients with HNSCC recruited between 1992 and 2005 using automated quantitative protein analysis (AQUA). We evaluated associations with clinicopathological parameters and prognosis. RESULTS: There were 67 patients with primary squamous cell carcinoma of the head and neck in this cohort who met inclusion criteria and for whom we had complete E-cadherin, beta-catenin and EGFR expression data. High E-cadherin expressers had longer 5-year progression-free survival (PFS) compared to those with low E-cadherin (59.7% versus 40.6%, p = 0.04) and overall survival (OS) (69.6% versus 44.3%, p  = 0.05). Kaplan-Meier analysis showed that patients with low beta-catenin-expressing tumors trended toward worse 5-year PFS (p = 0.057). High EGFR expressers had inferior OS compared to low EGFR expressers (27.7% vs. 54%, p = 0.029). In the multivariable analysis context, E-cadherin remained an independent predictor of improved OS (HR = 0.204, 95% CI 0.043 to 0.972, p = 0.046) while EGFR trended towards significance for OS. CONCLUSIONS: The putative markers of EMT defined within a panel of HNSCC using AQUA are associated with tumors of poor prognosis.