Discrimination between Complete versus Non-Complete Pathologic Response to Neoadjuvant Therapy Using Ultrasensitive Mutation Analysis: A Proof-of-Concept Study in BRCA1-Driven Breast Cancer Patients.

Neoadjuvant chemotherapy (NACT) for breast cancer (BC) often results in pathologic complete response (pCR), i.e., the complete elimination of visible cancer cells. It is unclear whether the use of ultrasensitive genetic methods may still detect residual BC cells in complete responders. Breast carcinomas arising in BRCA1 mutation carriers almost always carry alterations of the TP53 gene thus providing an opportunity to address this question. The analysis of consecutive BC patients treated by NACT revealed a higher pCR rate in BRCA1-driven vs. BRCA1-wildtype BCs (13/24 (54%) vs. 29/192 (15%), p < 0.0001). Twelve pre-/post-NACT tissue pairs obtained from BRCA1 mutation carriers were available for the study. While TP53 mutation was identified in all chemonaive tumors, droplet digital PCR (ddPCR) analysis of the post-NACT tumor bed revealed the persistence of this alteration in all seven pCR-non-responders but in none of five pCR responders. Eleven patients provided to the study post-NACT tissue samples only; next-generation sequencing (NGS) analysis revealed mutated TP53 copies in all six cases without pCR but in none of five instances of pCR. In total, TP53 mutation was present in post-NACT tissues in all 13 cases without pCR, but in none of 10 patients with pCR (p < 0.000001). Therefore, the lack of visible tumor cells in the post-NACT tumor bed is indeed a reliable indicator of the complete elimination of transformed clones. Failure of ultrasensitive methods to identify patients with minimal residual disease among pCR responders suggests that the result of NACT is a categorical rather than continuous variable, where some patients are destined to be cured while others ultimately fail to experience tumor eradication.

Minimal PK/PD model for simultaneous description of the maximal tolerated dose and metronomic treatment outcomes in mouse tumor models.

PURPOSE: Metronomic chemotherapy (MC) is a promising approach where, in contrast to the conventional maximal tolerated dose (MTD) strategy, regular fractionated doses of the drug are used. This approach has proven its efficacy, although drug dosing and scheduling are often chosen empirically. Pharmacokinetic/pharmacodynamic (PK/PD) models provide a way to choose optimal protocols with computational methods. Existing models are usually too complicated and are valid for only a subset of drug schedules. To address this issue, we propose herein a simple model that can describe MC and MTD regimens simultaneously. METHODS: The minimal model comprises tumor suppression due to antiangiogenic drug effect together with a cell-kill term, responsible for its cytotoxicity. The model was tested on data obtained on tumor-bearing mice treated with gemcitabine in ether MTD, MC, or combined (MTD + MC) regimens. RESULTS: We conducted a number of tests in which data were divided in various ways into training and validation sets. The model successfully described different trends in the MTD and MC regimens. With parameters obtained by fitting the model to MTD data, the simulations correctly predicted trends in both the MC and combined therapy groups. CONCLUSION: Our results demonstrate that the proposed model presents a minimal yet efficient tool for modeling outcomes in different treatment regimens in mice. We hope that this model has the potential for use in clinical practice in the development of patient-specific chemotherapy scheduling protocols based on observed treatment response.

Efficacy of immune checkpoint blockade in MUTYH-associated hereditary colorectal cancer.

Colorectal carcinomas (CRCs) caused by hereditary biallelic MUTYH gene mutations are characterized by elevated mutation load and high lymphocyte infiltration. Given that these tumor features are associated with the response to immune checkpoint inhibitors, we administered nivolumab to a CRC patient who carried two inactive MUTYH alleles (p.Y179C and p.G396D) and previously experienced failure of chemotherapy. This experimental treatment resulted in a pronounced tumor response. We further compared tumor lymphocyte infiltration in MUTYH-associated (n = 3), high-level microsatellite instability (MSI-H, n = 8) and microsatellite stable (MSS, n = 6) CRCs. Both MUTYH-driven and MSI-H CRCs showed noticeably higher lymphocyte densities than those of microsatellite stable tumors; this difference reached the level of statistical significance for the comparison of central areas of the tumors (p = 0.02 and 0.03, respectively) but not for the invasive tumor margins. Although MUTYH-associated tumors are exceptionally rare among unselected CRC cases, their share in CRC patients with somatic KRAS p.G12C substitution approaches 5-25%. These observations provide a rationale for further evaluation of the efficacy of the immune checkpoint blockade in MUTYH-driven CRC.

Lack of Response to Vemurafenib in Melanoma Carrying BRAF K601E Mutation.

Vemurafenib has been developed to target common BRAF mutation V600E. It also exerts activity towards some but not all rare BRAF substitutions. Proper cataloguing of drug-sensitive and -insensitive rare mutations remains a challenge, due to low occurrence of these events and inability of commercial PCR-based diagnostic kits to detect the full spectrum of BRAF gene lesions. We considered the results of BRAF exon 15 testing in 1872 consecutive melanoma patients. BRAF mutation was identified in 1,090 (58.2%) cases. While drug-sensitive codon 600 substitutions constituted the majority of BRAF gene lesions (V600E: 962 [51.4%]; V600K: 86 [4.6%]; V600R: 17 [0.9%]), the fourth common BRAF allele was K601E accounting for 9 (0.5%) melanoma cases. The data on BRAF inhibitor sensitivity of tumors with K601E substitution are scarce. We administered single-agent vemurafenib to a melanoma patient carrying BRAF K601E mutation as the first-line treatment. Unfortunately, this therapy did not result in a tumor response. Taken together with already published data, this report indicates lack of benefit from conventional BRAF inhibitors in patients with BRAF K601E mutated melanoma.

Variability in lung cancer response to ALK inhibitors cannot be explained by the diversity of ALK fusion variants.

Multiple laboratory evidences indicate that distinct variants of ALK translocations differ in their biochemical properties and responsiveness to ALK tyrosine kinase inhibitors (TKIs). These data are supported by some clinical studies, which showed improved responses to crizotinib in non-small cell lung cancer (NSCLC) patients carrying particular variants of ALK translocation. We retrospectively considered 64 Russian patients with ALK-rearranged NSCLC, who were treated by crizotinib (n = 23), ceritinib (n = 39) or alectinib (n = 2). ALK fusion variants were genotyped by PCR. Median progression-free survival (PFS) approached to 18 and 21 months in subjects with "short" (v.3a/b, v.5a/b) vs. "long" (TAPE-domain containing) fusion variants (p = 0.783), respectively; similar data were obtained while comparing EML4/ALK variant 1 vs. other ALK translocations (19 and 21 months, respectively; p = 0.604). Objective response rates were also strikingly similar in the above groups ("short": 88%, "long": 77%, p = 0.479; variant 1: 76%, other translocations: 81%, p = 0.753). Furthermore, ALK variants did not influence the disease outcomes when patients treated by crizotinib and ceritinib were analyzed separately. Overall, PFS on ALK TKI did not depend on whether the drug was administered upfront or after chemotherapy. Ceritinib produced significantly longer PFS than crizotinib (p = 0.022). In conclusion, this study revealed that distinct ALK translocation variants render similar clinical responsiveness to ALK inhibitors.

EGFR T790M Mutation in TKI-Naïve Clinical Samples: Frequency, Tissue Mosaicism, Predictive Value and Awareness on Artifacts.

BACKGROUND: This study evaluated the distribution of epidermal growth factor receptor (EGFR) T790M mutations in treatment-naïve tumor and normal samples obtained from cancer patients. METHODS: We utilized allele-specific PCR (AS-PCR), digital droplet PCR (ddPCR) and next generation sequencing (NGS) to detect EGFR T790M allele in several collections of tumor and normal human tissues. RESULTS: AS-PCR analysis of treatment-naïve tumor samples revealed somatic T790M mutation in 3/394 (1%) non-small cell lung carcinomas (NSCLC) carrying the tyrosine kinase inhibitor (TKI)-sensitizing EGFR mutation, but in none of 334 NSCLC lacking EGFR exon 19 deletions (ex19del) or L858R substitutions and in none of 235 non-lung tumors. Use of highly sensitive and quantitative assays, such as ddPCR and NGS, produced a high number of T790M-specific signals even in presumably T790M-negative DNA specimens. This background noise was evidently higher in degraded DNA isolated from formalin-fixed paraffin-embedded tissues as compared to high molecular weight DNA. A combination of AS-PCR, ddPCR and NGS revealed mosaic EGFR T790M allele in 2/68 (3%) NSCLC treated with the first-generation TKI. Both these tumors produced evident and durable response to gefitinib. CONCLUSION: Detection of mosaic EGFR T790M mutation in treatment-naïve samples may be compromised by yet unresolved technical issues and may have limited clinical value.

"Lazarus Response" to Olaparib in a Virtually Chemonaive Breast Cancer Patient Carrying Gross BRCA2 Gene Deletion.

This report describes an estrogen receptor-positive breast cancer patient, who relapsed at two and a half years after the completion of adjuvant chemotherapy while being on the aromatase inhibition. Based on the clinical evidence for potential sensitivity of the tumor to hormone ablation, everolimus was added to continuing exemestane treatment. Oral chemotherapy was administered at further disease progression, however, it lasted only for 10 days due to rapidly deteriorating condition of the patient. BRCA test was performed just before the failure of endocrine therapy and revealed a gross deletion within BRCA2 gene. Since the patient already developed contraindications to the standard chemotherapy, olaparib (300 mg twice a day) was given as a last hope option. The patient demonstrated a "Lazarus response": the performance status and the results of the biochemical tests went back to the norm within first two weeks of treatment. Positron emission tomography-computed tomography (PET-CT) was performed at one month after the start of olaparib therapy, and revealed complete metabolic response for all multiple metastatic lesions located in the liver, bones, small pelvis, lungs, mediastinum, retroperitoneum, etc. Cytotoxic therapy and poly ADP-ribose polymerase (PARP) inhibitors are known to have virtually identical mechanisms of tumor escape from the treatment, which are confined to the restoration of BRCA proficiency within cancer cells. The pronounced tumor response to the treatment in this patient can be attributed to the lack of recent exposure to standard cytotoxic treatment as well as to the inability of tumors with gross BRCA rearrangements to restore BRCA function via secondary mutation. This observation calls for comprehensive evaluation of PARP inhibitors in chemonaive patients with hereditary cancer.

First-Line Cetuximab Monotherapy in KRAS/NRAS/BRAF Mutation-Negative Colorectal Cancer Patients.

BACKGROUND: Colorectal carcinomas (CRCs) are sensitive to treatment by anti-epidermal growth factor receptor (EGFR) antibodies only if they do not carry activating mutations in down-stream EGFR targets (KRAS/NRAS/BRAF). Most clinical trials for chemo-naive CRC patients involved combination of targeted agents and chemotherapy, while single-agent cetuximab or panitumumab studies included either heavily pretreated patients or subjects who were not selected on the basis of molecular tests. We hypothesized that anti-EGFR therapy would have significant efficacy in chemo-naive patients with KRAS/NRAS/BRAF mutation-negative CRC. METHODS: Nineteen patients were prospectively included in the study. RESULTS: Two (11%) patients experienced partial response (PR) and 11 (58%) subjects showed stable disease (SD). Median time to progression approached 6.1 months (range 1.6-15.0 months). Cetuximab efficacy did not correlate with RNA expression of EGFR and insulin-like growth factor 2 (IGF2). Only one tumor carried PIK3CA mutation, and this CRC responded to cetuximab. Exome analysis of patients with progressive disease (PD) revealed 1 CRC with high-level microsatellite instability and 1 instance of HER2 oncogene amplification; 3 of 4 remaining patients with PD had allergic reactions to cetuximab, while none of the subjects with PR or SD had this complication. Comparison with 19 retrospective KRAS/NRAS/BRAF mutation-negative patients receiving first-line fluoropyrimidines revealed no advantages or disadvantages of cetuximab therapy. CONCLUSIONS: Cetuximab demonstrates only modest efficacy when given as a first-line monotherapy to KRAS/NRAS/BRAF mutation-negative CRC patients. It is of question, why meticulous patient selection, which was undertaken in the current study, did not result in the improvement of outcomes of single-agent cetuximab treatment.

Observed benefit and safety of aflibercept in elderly patients with metastatic colorectal cancer: An age-based analysis from the randomized placebo-controlled phase III VELOUR trial.

OBJECTIVES: Aflibercept (ziv-aflibercept) significantly improves progression-free (PFS) and overall survival (OS) when added to 5-fluorouracil, leucovorin and irinotecan (FOLFIRI), compared with FOLFIRI alone, in patients with metastatic colorectal cancer previously treated with oxaliplatin-based therapy. This subset analysis of the VELOUR study investigates aflibercept plus FOLFIRI versus placebo plus FOLFIRI according to age. METHODS: Efficacy and safety were analyzed by treatment arm and age (≥ or <65years). RESULTS: Overall, 443 patients were ≥65years old (205 in aflibercept arm; 238 in placebo arm) and 783 were <65years old (407 in aflibercept arm; 376 in placebo arm). Median OS was 12.6 versus 11.3months (hazard ratio [HR]: 0.85; 95.34% CI 0.68-1.07) in patients ≥65years old and 14.5 versus 12.5months (HR: 0.80; 95.34% CI 0.67-0.95) in those patients <65years old, for patients receiving FOLFIRI plus aflibercept or placebo, respectively. There was no interaction between treatment and age. Treatment-emergent adverse events (AEs) were comparable for patients <65years and ≥65years old. The incidence of grade 3/4 AEs was higher for patients ≥65years old than for those <65years old in both the aflibercept (89.3% versus 80.5%) and placebo (67.4% versus 59.4%) arms. Interaction tests for grade 3/4 antiangiogenic agent-related AEs suggested no heterogeneity between the older and younger patient populations (p>0.1). CONCLUSION: A limited but consistent benefit on both OS and PFS was associated with the addition of aflibercept to FOLFIRI compared with placebo in patients <65 and ≥65years old, with a marked but manageable increase in the toxicity profile in older patients. TRIAL REGISTRATION: clinicaltrials.govNCT00561470.

Survival Outcomes in EGFR Mutation-Positive Lung Cancer Patients Treated with Gefitinib until or beyond Progression.

BACKGROUND: Discontinuation of gefitinib treatment is often accompanied by a disease flare. Some studies have demonstrated a benefit of the use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) beyond progression; however, long-term results of these investigations remain limited. PATIENTS AND METHODS: We observed 70 patients with EGFR-mutated (EGFR-M+) non-small cell lung cancer (NSCLC) receiving single-agent gefitinib in a routine clinical setting; 56 patients were experiencing RECIST progression at the time of the analysis. RESULTS: There was a significant increase (p = 0.00001) in overall survival (OS) in patients continuing on gefitinib beyond progression (n = 21; median duration of continued gefitinib use: 4.2 months; median OS: not reached; expected OS: 29.7 months) as compared to those who stopped gefitinib treatment upon disease progression (n = 35; median OS: 14.0 months). The association between extended gefitinib use and improved OS remained true in multivariate Cox regression analysis (hazard ratio = 4.49, 95% confidence interval 1.25-16.09; p = 0.021). Patient selection bias constitutes an essential limitation of this clinical observational study, given that patients with a more favorable disease course and/or high initial tumor sensitivity to TKI treatment were more likely to be considered for prolonged gefitinib use. CONCLUSION: This study confirms that continued administration of gefitinib beyond progression is a viable treatment option for some patients with EGFR-M+ NSCLC, in particular those who cannot be rescued by novel EGFR mutation-specific inhibitors such as osimertinib.

Aflibercept Plus FOLFIRI vs. Placebo Plus FOLFIRI in Second-Line Metastatic Colorectal Cancer: a Post Hoc Analysis of Survival from the Phase III VELOUR Study Subsequent to Exclusion of Patients who had Recurrence During or Within 6 Months of Completing Adjuvant Oxaliplatin-Based Therapy.

The aim of this post hoc analysis of the VELOUR study (ClinicalTrials.gov NCT00561470) was to investigate the treatment effect of adding aflibercept to second-line infusional 5-fluorouracil (5-FU), leucovorin and irinotecan (FOLFIRI) in patients with metastatic colorectal cancer (mCRC) who had failed any prior oxaliplatin-containing regimen. Adjuvant rapid relapsers (ARR), who were enrolled directly following relapse during or within 6 months of completion of oxaliplatin-containing adjuvant chemotherapy (N = 124, including 17 patients who also received bevacizumab as part of their adjuvant therapy), were excluded from the original VELOUR intention-to-treat (ITT) population (N = 1226). After exclusion of the ARR, overall survival (OS) in the ITT minus ARR (ITT-ARR) population (N = 1102) was longer in the aflibercept plus FOLFIRI arm than in the placebo plus FOLFIRI arm [hazard ratio (HR) 0.78, 95 % confidence interval (CI) 0.68-0.90; median survival difference 1.87 months]. In the subgroup of patients assigned to the prior bevacizumab stratum at randomization, OS was numerically longer in the aflibercept plus FOLFIRI arm than in the placebo plus FOLFIRI arm (HR 0.81; 95 % CI 0.63-1.04; median survival difference 2.14 months). Comparison of the post hoc analysis results with the primary analysis from VELOUR suggests that the inclusion of the directly enrolled ARR may have understated the aflibercept treatment benefit for both bevacizumab-pretreated and bevacizumab-naïve patients in the strictly second-line setting although no definitive conclusion may be inferred. The benefit associated with the addition of aflibercept to second-line FOLFIRI in patients with mCRC was observed whatever the timing of first-line disease progression. There were no unexpected safety concerns.

High efficacy of cisplatin neoadjuvant therapy in a prospective series of patients carrying BRCA1 germ-line mutation.

Development of malignancies in BRCA1 germ-line mutation carriers usually involves somatic inactivation of the remaining BRCA1 allele. This feature leads to a tumor-specific deficiency of double-strand DNA break repair and underlies pronounced sensitivity of BRCA1-driven cancers to cisplatin. BRCA1-specific activity of cisplatin has been repeatedly demonstrated in cell culture and animal experiments; however, corresponding clinical evidence remains limited. We applied neoadjuvant monotherapy by cisplatin (75-100 mg/m(2), 4-6 cycles) to six breast cancer patients carrying BRCA1 5382insC mutation. Pronounced reduction in tumor size was observed in all treated women. Three patients (T2N0M0, T4N2M0 and T4N2M0) showed pathologic complete response, two women (T4N0M0 and T2N1M0) had partial pathologic response, and one woman (T3N2M0) declined surgery. This study and available literature data suggest that cisplatin is a preferable option for systemic treatment of BRCA1-related hereditary breast cancer.

Time course of safety and efficacy of aflibercept in combination with FOLFIRI in patients with metastatic colorectal cancer who progressed on previous oxaliplatin-based therapy.

BACKGROUND: Patients with metastatic colorectal cancer (mCRC) previously-treated with oxaliplatin benefit significantly from the addition of aflibercept to FOLFIRI in relation to overall survival, progression-free survival and response rate. PATIENTS AND METHODS: The results for efficacy and safety over the time course of the VEGF Trap (aflibercept) with irinotecan in colorectal cancer after failure of oxaliplatin regimen trial were analysed based on data from 1226 patients randomised to receive FOLFIRI plus either aflibercept (n=612) or placebo (n=614). Hazard ratios (HR) by 6-month time period were estimated using a piecewise Cox proportional hazard model. Severity of adverse events (AEs) was graded using National Cancer Institute Common Terminology Criteria, version 3.0. RESULTS: The estimated probabilities of survival were 38.5% versus 30.9% at 18 months, 28.0% versus 18.7% at 24 months and 22.3% versus 12.0% at 30 months, for the aflibercept- and placebo-treated arms, respectively. The proportional improvement in the HR over time was consistent with the survival probability results; survival at 24 months was improved by 50% and almost doubled at 30 months. The majority of worst-grade AEs occurred within the first four cycles of treatment and in a small percent of treatment cycles and were mostly reversible. Common chemotherapy- and anti-vascular epithelial growth factor (VEGF)-associated AEs occurred rarely and in a small proportion of cycles with the majority being of single occurrence. CONCLUSIONS: The addition of aflibercept to FOLFIRI showed a continued and persistent improvement in overall survival over time in patients with mCRC. Although grade 3-4 AEs were more frequent in the aflibercept arm, they occurred in early treatment cycles and decreased sharply following initial presentation.

Evidence for clinical efficacy of mitomycin C in heavily pretreated ovarian cancer patients carrying germ-line BRCA1 mutation.

Ovarian carcinomas (OC) arising in BRCA1 and BRCA2 mutation carriers demonstrate pronounced sensitivity to platinum-based therapy due to deficiency of double-strand break DNA repair. However, the choice of subsequent treatment lines for this category of women remains complicated. We considered mitomycin C for heavily pretreated hereditary OC patients, based on multiple evidence for BRCA-specific activity of this drug. Twelve patients carrying BRCA1 germ-line mutation were included in the study. All women had a history of surgical intervention followed by adjuvant platinum-based therapy; three patients also received platinating agents prior the operation. The number of preceding treatment lines for metastatic disease was one for three patients, two for four patients, three for two patients, four for two patients and six for one woman. Administration of mitomycin C (10 mg/m2, every 4 weeks) resulted in one complete response (duration 36 weeks), two partial responses (duration 36 and 48 weeks) and six instances of disease stabilization (duration 12, 16, 20, 24, 24 and 24 weeks). In addition, three patients with the stable disease showed a decline of CA-125 level. We conclude that mitomycin C may deserve further evaluation in clinical trials involving BRCA1/2-related cancers.

Quality of life in the trastuzumab for gastric cancer trial.

BACKGROUND: The Trastuzumab for Gastric Cancer phase III trial demonstrated that combining trastuzumab with chemotherapy significantly improved overall survival compared with chemotherapy alone in HER2-positive advanced gastric or gastroesophageal junction cancer. We report health-related quality of life (HRQoL) and quality-adjusted time without symptoms of disease or toxicity (Q-TWiST) results from this trial. PATIENTS AND METHODS: Patients were randomized to receive six cycles of chemotherapy given every 3 weeks (capecitabine or fluorouracil, plus cisplatin) either alone or combined with administration of trastuzumab every 3 weeks until disease progression. At each clinical visit, HRQoL was assessed using two European Organization for Research and Treatment of Cancer quality of life questionnaires, QLQ-C30 and QLQ-STO22. Q-TWiST methodology was applied retrospectively using the clinical data and utility coefficients. RESULTS: Trastuzumab plus chemotherapy prolonged time to 10% definitive deterioration in all QLQ-C30 and QLQ-STO22 scores, including QLQ-C30 global health status versus chemotherapy alone, from 6.4 months to 10.2 months. In addition, trastuzumab plus chemotherapy extended Q-TWiST by 2.42 months compared with chemotherapy alone. CONCLUSION: Compared with chemotherapy alone, trastuzumab plus chemotherapy prolongs time to deterioration of HRQoL and increases quality-adjusted survival in patients with HER2-positive gastric or gastroesophageal junction cancer.

Aflibercept versus placebo in combination with fluorouracil, leucovorin and irinotecan in the treatment of previously treated metastatic colorectal cancer: prespecified subgroup analyses from the VELOUR trial.

PURPOSE: The antiangiogenic agent aflibercept (ziv-aflibercept in the United States) in combination with 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) significantly improved survival in a phase III study of patients with metastatic colorectal cancer (mCRC) previously treated with an oxaliplatin-based regimen. In the present analysis, outcomes were evaluated in prespecified subgroups to assess the consistency of the treatment effect. METHODS: Patients were randomised to receive FOLFIRI plus aflibercept or placebo every 2weeks until disease progression or unacceptable toxicity occurred. Efficacy and safety outcomes were analysed with respect to demographic and baseline characteristics, and stratification factors (prior bevacizumab treatment and Eastern Cooperative Oncology Group performance status). RESULTS: Median overall survival (OS, months [95.34% confidence interval (CI)]) for aflibercept versus placebo was 12.5 (10.8-15.5) versus 11.7 (9.8-13.8) in patients with prior bevacizumab treatment and 13.9 (12.7-15.6) versus 12.4 (11.2-13.5) in patients with no prior bevacizumab treatment. The p value for interaction was 0.5668, indicating there was no heterogeneity in these subgroups. For OS and progression-free survival (PFS), there was a significantly greater benefit (at the 2-sided 10% level) of treatment for patients with liver only metastases versus patients with no liver metastases/liver metastases with other organ involvement (p value for interaction: 0.0899 [OS]; 0.0076 [PFS]). There was no evidence of heterogeneity in treatment effect in any of the other subgroups examined. CONCLUSIONS: The benefits of aflibercept in combination with FOLFIRI in patients with mCRC previously treated with oxaliplatin were maintained across the specified patient subgroups, including in patients with or without prior bevacizumab treatment.

Capecitabine and cisplatin with or without cetuximab for patients with previously untreated advanced gastric cancer (EXPAND): a randomised, open-label phase 3 trial.

BACKGROUND: Patients with advanced gastric cancer have a poor prognosis and few efficacious treatment options. We aimed to assess the addition of cetuximab to capecitabine-cisplatin chemotherapy in patients with advanced gastric or gastro-oesophageal junction cancer. METHODS: In our open-label, randomised phase 3 trial (EXPAND), we enrolled adults aged 18 years or older with histologically confirmed locally advanced unresectable (M0) or metastatic (M1) adenocarcinoma of the stomach or gastro-oesophageal junction. We enrolled patients at 164 sites (teaching hospitals and clinics) in 25 countries, and randomly assigned eligible participants (1:1) to receive first-line chemotherapy with or without cetuximab. Randomisation was done with a permuted block randomisation procedure (variable block size), stratified by disease stage (M0 vs M1), previous oesophagectomy or gastrectomy (yes vs no), and previous (neo)adjuvant (radio)chemotherapy (yes vs no). Treatment consisted of 3-week cycles of twice-daily capecitabine 1000 mg/m(2) (on days 1-14) and intravenous cisplatin 80 mg/m(2) (on day 1), with or without weekly cetuximab (400 mg/m(2) initial infusion on day 1 followed by 250 mg/m(2) per week thereafter). The primary endpoint was progression-free survival (PFS), assessed by a masked independent review committee in the intention-to-treat population. We assessed safety in all patients who received at least one dose of study drug. This study is registered at EudraCT, number 2007-004219-75. FINDINGS: Between June 30, 2008, and Dec 15, 2010, we enrolled 904 patients. Median PFS for 455 patients allocated capecitabine-cisplatin plus cetuximab was 4.4 months (95% CI 4.2-5.5) compared with 5.6 months (5.1-5.7) for 449 patients who were allocated to receive capecitabine-cisplatin alone (hazard ratio 1.09, 95% CI 0.92-1.29; p=0.32). 369 (83%) of 446 patients in the chemotherapy plus cetuximab group and 337 (77%) of 436 patients in the chemotherapy group had grade 3-4 adverse events, including grade 3-4 diarrhoea, hypokalaemia, hypomagnesaemia, rash, and hand-foot syndrome. Grade 3-4 neutropenia was more common in controls than in patients who received cetuximab. Incidence of grade 3-4 skin reactions and acne-like rash was substantially higher in the cetuximab-containing regimen than in the control regimen. 239 (54%) of 446 in the cetuximab group and 194 (44%) of 436 in the control group had any grade of serious adverse event. INTERPRETATION: Addition of cetuximab to capecitabine-cisplatin provided no additional benefit to chemotherapy alone in the first-line treatment of advanced gastric cancer in our trial. FUNDING: Merck KGaA.

Evidence for predictive role of BRCA1 and bTUBIII in gastric cancer.

Sensitivity of gastric cancer (GC) to conventional cytotoxic therapy may be at least in part attributed to molecular features of the tumor cells. We analyzed all patients with metastatic GC treated in the N.N. Petrov Institute of Oncology (St. Petersburg) within years 1999-2010 and identified 65 cases with evaluable treatment response and available biological material. Two of 65 patients (3 %) carried germ-line BRCA1 5382insC mutation and demonstrated particularly pronounced response to the treatment; both of their tumors showed loss of the remaining BRCA1 allele, thus confirming the causative role of BRCA1 heterozygosity in GC predisposition. RNA expression of TS, DPD, BRCA1, ERCC, TOP2A and bTUBIII was analyzed in the remaining 63 tumors. Low BRCA1 expression was associated with increased response rate [6/9 (67 %) vs. 17/54 (32 %), p = 0.04]. Low bTUBIII level correlated with the improved probability of tumor response [21/49 (43 %) vs. 1/13 (8 %), p = 0.02] and prolonged overall survival (10.5 vs. 7.1 months, p = 0.02); this trend was maintained both for taxane-containing and for taxane-free drug combinations. We conclude that GC should be considered as a part of BRCA1-related hereditary cancer syndrome. Tumors with BRCA1 inactivation and low bTUBIII expression demonstrate improved response to cytotoxic therapy.

KIT mutations in Russian patients with mucosal melanoma.

A single institution series of 48 mucosal melanomas (MMs) has been analyzed for the presence of KIT mutations using high-resolution melting and sequencing of abnormally melted DNA fragments. The analysis of exons 9, 11, 13, and 17 has revealed eight of 48 (17%) nonsynonymous alterations, including zero of seven head and neck, six of 24 anorectal, one of 15 genitourinary, one of one gastric, and zero of one mediastinal MMs. Seven of these mutations were potentially associated with the tumor sensitivity to KIT tyrosine kinase inhibitors. One tumor harbored somatically acquired silent nucleotide substitution c.1383A>G (T461T). This study adds to the evidence that a substantial portion of MMs carry a therapeutically relevant mutation in the KIT oncogene.