George Fountzilas

Effects of KRAS, BRAF, NRAS, and PIK3CA mutations on the efficacy of cetuximab plus chemotherapy in chemotherapy-refractory metastatic colorectal cancer: a retrospective consortium analysis

BACKGROUND Following the discovery that mutant KRAS is associated with resistance to anti-epidermal growth factor receptor (EGFR) antibodies, the tumours of patients with metastatic colorectal cancer are now profiled for seven KRAS mutations before receiving cetuximab or panitumumab. However, most patients with KRAS wild-type tumours still do not respond. We studied the effect of other downstream mutations on the efficacy of cetuximab in, to our knowledge, the largest cohort to date of patients with chemotherapy-refractory metastatic colorectal cancer treated with cetuximab plus chemotherapy in the pre-KRAS selection era. METHODS 1022 tumour DNA samples (73 from fresh-frozen and 949 from formalin-fixed, paraffin-embedded tissue) from patients treated with cetuximab between 2001 and 2008 were gathered from 11 centres in seven European countries. 773 primary tumour samples had sufficient quality DNA and were included in mutation frequency analyses; mass spectrometry genotyping of tumour samples for KRAS, BRAF, NRAS, and PIK3CA was done centrally. We analysed objective response, progression-free survival (PFS), and overall survival in molecularly defined subgroups of the 649 chemotherapy-refractory patients treated with cetuximab plus chemotherapy. FINDINGS 40.0% (299/747) of the tumours harboured a KRAS mutation, 14.5% (108/743) harboured a PIK3CA mutation (of which 68.5% [74/108] were located in exon 9 and 20.4% [22/108] in exon 20), 4.7% (36/761) harboured a BRAF mutation, and 2.6% (17/644) harboured an NRAS mutation. KRAS mutants did not derive benefit compared with wild types, with a response rate of 6.7% (17/253) versus 35.8% (126/352; odds ratio [OR] 0.13, 95% CI 0.07-0.22; p<0.0001), a median PFS of 12 weeks versus 24 weeks (hazard ratio [HR] 1.98, 1.66-2.36; p<0.0001), and a median overall survival of 32 weeks versus 50 weeks (1.75, 1.47-2.09; p<0.0001). In KRAS wild types, carriers of BRAF and NRAS mutations had a significantly lower response rate than did BRAF and NRAS wild types, with a response rate of 8.3% (2/24) in carriers of BRAF mutations versus 38.0% in BRAF wild types (124/326; OR 0.15, 95% CI 0.02-0.51; p=0.0012); and 7.7% (1/13) in carriers of NRAS mutations versus 38.1% in NRAS wild types (110/289; OR 0.14, 0.007-0.70; p=0.013). PIK3CA exon 9 mutations had no effect, whereas exon 20 mutations were associated with a worse outcome compared with wild types, with a response rate of 0.0% (0/9) versus 36.8% (121/329; OR 0.00, 0.00-0.89; p=0.029), a median PFS of 11.5 weeks versus 24 weeks (HR 2.52, 1.33-4.78; p=0.013), and a median overall survival of 34 weeks versus 51 weeks (3.29, 1.60-6.74; p=0.0057). Multivariate analysis and conditional inference trees confirmed that, if KRAS is not mutated, assessing BRAF, NRAS, and PIK3CA exon 20 mutations (in that order) gives additional information about outcome. Objective response rates in our series were 24.4% in the unselected population, 36.3% in the KRAS wild-type selected population, and 41.2% in the KRAS, BRAF, NRAS, and PIK3CA exon 20 wild-type population. INTERPRETATION While confirming the negative effect of KRAS mutations on outcome after cetuximab, we show that BRAF, NRAS, and PIK3CA exon 20 mutations are significantly associated with a low response rate. Objective response rates could be improved by additional genotyping of BRAF, NRAS, and PIK3CA exon 20 mutations in a KRAS wild-type population. FUNDING Belgian Federation against Cancer (Stichting tegen Kanker).

Paclitaxel Plus Carboplatin Versus Gemcitabine Plus Paclitaxel in Advanced Non–Small-Cell Lung Cancer: A Phase III Randomized Trial

PURPOSE We conducted this randomized study comparing the activity and toxicity of paclitaxel and gemcitabine (PG) and paclitaxel and carboplatin (PC) combinations for the treatment of advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Chemotherapy-naive patients were randomized to paclitaxel 200 mg/m(2) on day 1 plus either carboplatin at an area under the concentration-time curve of 6 on day 1 (group A) or gemcitabine 1,000 mg/m(2) on days 1 and 8 (group B) every 3 weeks. A retrospective cost analysis was conducted using Students t test to compare independent samples between groups. RESULTS A total of 509 patients (group A, 252 patients; group B, 257 patients) were enrolled; all characteristics were well balanced. The median survival time was 10.4 months (95% confidence interval [CI], 8.8 to 12 months) for group A and 9.8 months (95% CI, 8.0 to 11.7 months) for group B (P =.32). Respective 1-year survival rates were 41.7% and 41.4%. The response rate for group A was 28.0% (2% complete response [CR], 26% partial response [PR] [95% CI, 22% to 34%]), and the response rate for group B was 35.0% (5% CR, 30% PR) [95% CI, 29% to 41%]) (P =.12). Toxicity was mild. Grades 3/4 neutropenia, thrombocytopenia, and anemia for groups A and B were seen in 15% and 15%, 2% and 1%, and 5% and 2%, respectively. The mean total cost (outpatient clinic visits plus chemotherapy drug fee) for group A (euro; 7,612.64) versus group B (euro; 7,484.77) was not statistically significant (P <.66). CONCLUSION The PG combination is as equally active and well tolerated as the PC combination in patients with advanced NSCLC.

Inherited Mutations in 17 Breast Cancer Susceptibility Genes Among a Large Triple-Negative Breast Cancer Cohort Unselected for Family History of Breast Cancer

PURPOSE Recent advances in DNA sequencing have led to the development of breast cancer susceptibility gene panels for germline genetic testing of patients. We assessed the frequency of mutations in 17 predisposition genes, including BRCA1 and BRCA2, in a large cohort of patients with triple-negative breast cancer (TNBC) unselected for family history of breast or ovarian cancer to determine the utility of germline genetic testing for those with TNBC. PATIENTS AND METHODS Patients with TNBC (N = 1,824) unselected for family history of breast or ovarian cancer were recruited through 12 studies, and germline DNA was sequenced to identify mutations. RESULTS Deleterious mutations were identified in 14.6% of all patients. Of these, 11.2% had mutations in the BRCA1 (8.5%) and BRCA2 (2.7%) genes. Deleterious mutations in 15 other predisposition genes were detected in 3.7% of patients, with the majority observed in genes involved in homologous recombination, including PALB2 (1.2%) and BARD1, RAD51D, RAD51C, and BRIP1 (0.3% to 0.5%). Patients with TNBC with mutations were diagnosed at an earlier age (P < .001) and had higher-grade tumors (P = .01) than those without mutations. CONCLUSION Deleterious mutations in predisposition genes are present at high frequency in patients with TNBC unselected for family history of cancer. Mutation prevalence estimates suggest that patients with TNBC, regardless of age at diagnosis or family history of cancer, should be considered for germline genetic testing of BRCA1 and BRCA2. Although mutations in other predisposition genes are observed among patients with TNBC, better cancer risk estimates are needed before these mutations are used for clinical risk assessment in relatives.

Edrecolomab alone or in combination with fluorouracil and folinic acid in the adjuvant treatment of stage III colon cancer: a randomised study

BACKGROUND Edrecolomab is a murine monoclonal antibody to the cell-surface glycoprotein 17-1A, which is expressed on epithelial tissues and on various carcinomas. Preliminary data suggested that it might be of use in the adjuvant treatment of patients with resected stage III colon cancer. We did a randomised trial in 27 countries to determine the effect of adding edrecolomab to the combination of fluorouracil and folinic acid in these patients. METHODS After surgery, 2761 patients were randomly assigned edrecolomab plus fluorouracil-folinic acid (combination therapy [n=912]); fluorouracil-folinic acid alone (chemotherapy [n=927]); or edrecolomab alone (edrecolomab monotherapy [n=922]). Patients were assessed for survival and disease recurrence after surgery. The primary endpoint tested the hypothesis that combination therapy improved overall survival relative to chemotherapy. The key secondary endpoint was to test whether edrecolomab monotherapy was non-inferior to chemotherapy in terms of disease-free survival. Analysis was by intention to treat. FINDINGS Median follow-up time was 26 months (IQR 20-36). 3-year overall survival on combination therapy was no different from that on chemotherapy (74.7% vs 76.1%, hazard ratio 0.94 [95% CI 0.76-1.15], p=0.53). Disease-free survival was significantly lower on edrecolomab monotherapy than on chemotherapy (53.0% vs 65.5%, 0.62 [0.53-0.73], p<0.0001). Hypersensitivity reactions occurred in 452 (25%) patients receiving edrecolomab, causing treatment discontinuation in 71 (4%). The addition of edrecolomab to chemotherapy did not increase neutropenia, diarrhoea, or mucositis. INTERPRETATION The addition of edrecolomab to fluorouracil and folinic acid in the adjuvant treatment of resected stage III colon cancer does not improve overall or disease-free survival, and edrecolomab monotherapy is associated with significantly shorter overall and disease-free survival than fluorouracil and folinic acid and is therefore an inferior treatment option. Edrecolomab is well tolerated and its addition to fluorouracil and folinic acid does not increase the toxicity of chemotherapy.

Phase II Study of Sunitinib Administered in a Continuous Once-Daily Dosing Regimen in Patients With Cytokine-Refractory Metastatic Renal Cell Carcinoma

PURPOSE Sunitinib has demonstrated antitumor activity in metastatic renal cell carcinoma (mRCC) when given at 50 mg/d on a 4-weeks-on 2-weeks-off regimen. Herein, we report results of an open-label, multicenter phase II mRCC study of sunitinib administered on a continuous once-daily dosing regimen. PATIENTS AND METHODS Eligibility criteria included histologically proven mRCC with measurable disease, failure of one prior cytokine regimen, and good performance status. Patients were randomly assigned to a sunitinib starting dose of 37.5 mg/d in the morning (AM) or evening (PM). RECIST-defined objective response rate (ORR) was the primary end point. Secondary end points included progression-free survival (PFS), overall survival (OS), adverse events (AEs), and quality-of-life measures. RESULTS One hundred seven patients were randomly assigned to AM (n = 54) or PM (n = 53) dosing and on study for a median 8.3 months. Eighty-three patients discontinued, 65 due to disease progression and 16 because of AEs; two patients withdrew consent. Dosing was reduced to 25 mg/d in 46 patients (43%) due to grade 3/4 AEs. The most common grade 3 treatment-related AEs were asthenia/fatigue (16%), diarrhea (11%), hypertension (11%), hand-foot syndrome (9%), and anorexia (8%). ORR was 20% with a 7.2-month median response duration. Median PFS and OS were 8.2 and 19.8 months, respectively, at median follow-up of 26.4 months. Efficacy, tolerability, and quality-of-life results were similar between patients dosed in the AM or PM. CONCLUSION Sunitinib 37.5 mg, administered on a continuous once-daily dosing regimen, has a manageable safety profile as second-line mRCC therapy, providing flexible dosing, which can be explored in combination studies.

Trastuzumab in the Adjuvant Treatment of Early-Stage Breast Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND We performed a systematic review and meta-analysis to compare treatment outcomes for human epidermal growth factor receptor (HER)-2-positive breast cancer patients receiving adjuvant chemotherapy with or without trastuzumab. METHODS We identified randomized clinical trials comparing adjuvant chemotherapy with or without trastuzumab in patients with resectable breast cancer. Fixed-effects meta-analysis was used to combine data. RESULTS Five eligible trials were identified, reporting outcomes on 13,493 women. Fixed-effects analysis showed disease-free survival to be superior for trastuzumab-treated patients (risk ratio [RR], 0.62; 95% confidence interval [CI], 0.56-0.68). Superiority was also observed for patients receiving trastuzumab with respect to mortality (RR, 0.66; 95% CI, 0.57-0.77), locoregional recurrence (RR, 0.58; 95% CI, 0.43-0.77), and distant recurrence (RR, 0.60; 95% CI, 0.52-0.68). Patients receiving trastuzumab with chemotherapy had a higher risk for congestive heart failure (RR, 7.60; 95% CI, 4.07-14.18) and left ventricular ejection fraction decline (RR, 2.09; 95% CI, 1.84-2.37). A higher risk for central nervous system metastasis as the first recurrence event (RR, 1.60; 95% CI, 1.06-2.40) was also noted in patients receiving trastuzumab. CONCLUSIONS The use of trastuzumab should be considered an integral part of the adjuvant therapy of HER-2-positive breast cancer patients.

A multicenter phase III trial comparing irinotecan-gemcitabine (IG) with gemcitabine (G) monotherapy as first-line treatment in patients with locally advanced or metastatic pancreatic cancer

Our purpose was to determine the response rate and median and overall survival of gemcitabine as monotherapy versus gemcitabine plus irinotecan in advanced or metastatic pancreatic cancer. Patients with histologically or cytologically confirmed adenocarcinoma who were chemotherapy and radiotherapy naive were enrolled. Patients were centrally randomised at a one-to-one ratio to receive either gemcitabine monotherapy (900 mg m−2 on days 1, 8 and 15 every 4 weeks (arm G), or gemcitabine (days 1 and 8) plus irinotecan (300 mg m−2 on day 8) (arm IG), repeated every 3 weeks. The total number of cycles administered was 255 in the IG arm and 245 in the G arm; the median number of cycles was 3. In all, 145 patients (71 in arm IG and 74 in arm G) were enrolled; 60 and 70 patients from arms IG and G, respectively, were evaluable. A complete clinical response was achieved in three (4.3%) arm G patients; nine (15%) patients in arm IG and four (5.7%) in arm G achieved a partial response. The overall response rate was: arm IG 15% and arm G 10% (95% CI 5.96–24.04 and 95% CI 2.97–17.03, respectively; P=0.387). The median time to tumour progression was 2.8 months and 2.9 months and median survival time was 6.4 and 6.5 months for the IG and G arms, respectively. One-year survival was 24.3% for the IG arm and 21.8% for the G arm. No statistically significant difference was observed comparing gemcitabine monotherapy versus gemcitabine plus irinotecan in the treatment of advanced pancreatic cancer, with respect to overall and 1-year survival.

Carboplatin Plus Paclitaxel in Unknown Primary Carcinoma: A Phase II Hellenic Cooperative Oncology Group Study

PURPOSE To evaluate the efficacy of the carboplatin/paclitaxel combination in patients with carcinoma of unknown primary site (CUP). PATIENTS AND METHODS Seventy-seven consecutive CUP patients (45 women and 32 men; median age, 60 years) were treated with carboplatin at target area under the curve 6 mg/mL/min followed by paclitaxel 200 mg/m(2) as a 3-hour infusion and granulocyte colony-stimulating factor from days 5 to 12. Treatment courses were repeated every 3 weeks to a maximum of eight cycles. Forty-seven patients had adenocarcinomas, 27 had undifferentiated carcinomas, and three had squamous cell carcinomas. Thirty-three patients presented with liver, bone, or multiple organ metastases, 23 with predominantly nodal/pleural disease, and 19 (16 women) with peritoneal carcinomatosis. RESULTS The overall response rate by intent-to-treat analysis was 38.7% (95% confidence interval, 27.5% to 49.9%). There were no differences in response between adenocarcinomas and undifferentiated carcinomas, but efficacy varied among clinical subsets. The response rates and median survival times in the three clinically defined subsets were 47.8% and 13 months, respectively, for patients with predominantly nodal/pleural disease, 68.4% and 15 months, respectively, in women with peritoneal carcinomatosis, and 15.1% and 10 months, respectively, in patients with visceral or disseminated metastases. Chemotherapy was well-tolerated. CONCLUSION Carboplatin plus paclitaxel combination chemotherapy is effective in patients with predominantly nodal/pleural metastases of unknown primary carcinoma and in women with peritoneal carcinomatosis. However, in patients with liver, bone, or multiple organ involvement, the combination offers limited benefit. The investigation of novel treatment approaches is highly warranted for this group of patients.

Induction chemotherapy followed by concomitant radiotherapy and weekly cisplatin versus the same concomitant chemoradiotherapy in patients with nasopharyngeal carcinoma: a randomized phase II study conducted by the Hellenic Cooperative Oncology Group (HeCOG) with biomarker evaluation

BACKGROUND Concomitant administration of radiation therapy (RT) and chemotherapy with cisplatin (CCRT) is considered standard treatment in patients with locally advanced nasopharyngeal cancer (LA-NPC). The role of induction chemotherapy (IC) when followed by CCRT in improving locoregional control remains controversial. PATIENTS AND METHODS Totally, 141 eligible patients with LA-NPC were randomized to either three cycles of IC with cisplatin 75 mg/m(2), epirubicin 75 mg/m(2) and paclitaxel (Taxol) 175 mg/m(2) (CEP) every 3 weeks followed by definitive RT (70 Gy) and concomitant weekly infusion of cisplatin 40 mg/m(2) (investigational arm, 72 patients) or to the same CCRT regimen alone (control arm, 69 patients). RESULTS Sixty-two patients (86%) received three cycles of IC. No difference between the arms was observed in the number of patients who completed RT (61 versus 64, P = 018). Overall and complete response rates were very similar in the two arms and so were 3-year progression-free and overall survival rates. Grade III or IV toxic effects from IC were infrequent, apart of alopecia. Mucositis, weight loss and leukopenia were the most prominent side-effects from CCRT. CONCLUSION IC with three cycles of CEP when followed by CCRT did not significantly improve response rates and/or survival compared with that of CCRT alone.

Objective Response to Chemotherapy As a Potential Surrogate End Point of Survival in Metastatic Breast Cancer Patients

PURPOSE To assess the validity of objective response to chemotherapy as a surrogate end point for survival in metastatic breast cancer. PATIENTS AND METHODS We carried out a meta-analysis on individual data from 2,126 metastatic breast cancer patients who were enrolled onto 10 randomized trials comparing standard versus intensified epirubicin-containing chemotherapy. RESULTS The intensified chemotherapy was associated with a significantly higher tumor response rate compared with standard chemotherapy (pooled odds ratio for nonresponse, 0.60; 95% CI, 0.51 to 0.72). The intensified regimens also led to better (although not significant) survival (pooled odds ratio, 0.94; 95% CI, 0.86 to 1.04; P = .22). Tumor response was a highly significant predictor of survival (P < .0001). When tumor response was introduced in the Cox model, the hazard ratio in favor of experimental treatment changed from 0.94 to 1.005 (95% CI, 0.91 to 1.11; P = .92), indicating that no residual effect of the experimental treatment on survival was present once tumor response was adjusted for. This suggests that the overall survival benefit of intensified epirubicin was a result of the increase in response rate. The median survival time of patients with complete response and partial response was 28.8 months (95% CI, 25.4 to 45.3 months) and 21.3 months (95% CI, 19.2 to 22.4 months), respectively; whereas, the median survival time of patients with no response was 14.6 months (95% CI, 13.9 to 15.4 months). CONCLUSION These results support the hypothesis that the achievement of an objective response to chemotherapy in metastatic breast cancer is associated with a true survival benefit. The potential role of objective response as a surrogate end point for survival in chemotherapy trials of metastatic breast cancer warrants further investigation.