Purpose: We performed this phase III study to compare the irinotecan, leucovorin (LV), and fluorouracil (FU) regimen (FOLFIRI) versus the oxaliplatin, LV, and FU regimen (FOLFOX4) in previously untreated patients with advanced colorectal cancer. Patients and Methods: A total of 360 chemotherapy-naive patients were randomly assigned to receive, every 2 weeks, either arm A (FOLFIRI: irinotecan 180 mg/m² on day 1 with LV 100 mg/m² administered as a 2-hour infusion before FU 400 mg/m² administered as an intravenous bolus injection, and FU 600 mg/m² as a 22-hour infusion immediately after FU bolus injection on days 1 and 2 [LV5FU2]) or arm B (FOLFOX4: oxaliplatin 85 mg/m² on day 1 with LV5FU2 regimen). Results: One hundred sixty-four and 172 patients were assessable in arm A and B, respectively. Overall response rates (ORR) were 31% in arm A (95% CI, 24.6% to 38.3%) and 34% in arm B (95% CI, 27.2% to 41.5%; P = .60). In both arms A and B, median time to progression (TTP; 7 v 7 months, respectively), duration of response (9 v 10 months, respectively), and overall survival (OS; 14 v 15 months, respectively) were similar, without any statistically significant difference. Toxicity was mild in both groups: alopecia and gastrointestinal disturbances were the most common toxicities in arm A; thrombocytopenia and neurosensorial were the most common toxicities in arm B. Grade 3 to 4 toxicities were uncommon in both arms, and no statistical significant difference was observed. Conclusion: There is no difference in ORR, TTP, and OS for patients treated with the FOLFIRI or FOLFOX4 regimen. Both therapies seemed effective as first-line treatment in these patients. The difference between these two combination therapies is mainly in the toxicity profile.

Purpose: Single-agent gemcitabine became standard first-line treatment for advanced pancreatic cancer after demonstration of superiority compared with fluorouracil. The Gruppo Italiano Pancreas 1 randomized phase III trial aimed to compare gemcitabine plus cisplatin versus gemcitabine alone (ClinicalTrials.gov ID NCT00813696).Patients and Methods: Patients with locally advanced or metastatic pancreatic cancer, age 18 to 75 years, and Karnofsky performance status (KPS) ≥ 50, were randomly assigned to receive gemcitabine (arm A) or gemcitabine plus cisplatin (arm B). Arm A: gemcitabine 1,000 mg/m²weekly for 7 weeks, and, after a 1-week rest, on days 1, 8, and 15 every 4 weeks. Arm B: cisplatin 25 mg/m²added weekly to gemcitabine, except cycle 1 day 22. Primary end point was overall survival. To have 8% power of detecting a 0.74 hazard ratio (HR) of death, with bilateral α .05, 355 events were needed and 400 patients planned.Results: Four hundred patients were enrolled (arm A: 199; arm B: 201). Median age was 63, 59% were male, 84% had stage IV, and 83% had KPS ≥ 80. Median overall survival was 8.3 months versus 7.2 months in arm A and B, respectively (HR, 1.10; 95% CI, 0.89 to 1.35; P = .38). Median progression-free survival was 3.9 months versus 3.8 months in arm A and B, respectively (HR, 0.97; 95% CI, 0.80 to 1.19; P = .80). The objective response rate was 10.1% in A and 12.9% in B (P = .37). Clinical benefit was experienced by 23.0% in A and 15.1% in B (P = .057). Combination therapy produced more hematologic toxicity, without relevant differences in nonhematologic toxicity.Conclusion: The addition of weekly cisplatin to gemcitabine failed to demonstrate any improvement as first-line treatment of advanced pancreatic cancer.

PURPOSE: Limited prospective data are available on sequential immunotherapy and BRAF/MEK inhibition for BRAFV600-mutant metastatic melanoma. METHODS: SECOMBIT is a randomized, three-arm, noncomparative phase II trial (ClinicalTrials.gov identifier: NCT02631447 ). Patients with untreated, metastatic BRAFV600-mutant melanoma from 37 sites in nine countries were randomly assigned to arm A (encorafenib [450 mg orally once daily] plus binimetinib [45 mg orally twice daily] until progressive disease [PD] -> ipilimumab plus nivolumab [ipilimumab 3 mg/kg once every 3 weeks and nivolumab 1 mg/kg once every 3 weeks × four cycles -> nivolumab 3 mg/kg every 2 weeks]), arm B [ipilimumab plus nivolumab until PD -> encorafenib plus binimetinib], or arm C (encorafenib plus binimetinib for 8 weeks -> ipilimumab plus nivolumab until PD -> encorafenib plus binimetinib). The primary end point was overall survival (OS) at 2 years. Secondary end points included total progression-free survival, 3-year OS, best overall response rate, duration of response, and biomarkers in the intent-to-treat population. Safety was analyzed throughout sequential treatment in all participants who received at least one dose of study medication. RESULTS: A total of 209 patients were randomly assigned (69 in arm A, 71 in arm B, and 69 in arm C). At a median follow-up of 32.2 (interquartile range, 27.9-41.6) months, median OS was not reached in any arm and more than 30 patients were alive in all arms. Assuming a null hypothesis of median OS of ≤ 15 months, the OS end point was met for all arms. The 2-year and 3-year OS rates were 65% (95% CI, 54 to 76) and 54% (95% CI, 41 to 67) in arm A, 73% (95% CI, 62 to 84) and 62% (95% CI, 48 to 76) in arm B, and 69% (95% CI, 59 to 80) and 60% (95% CI, 58 to 72) in arm C. No new safety signals emerged. CONCLUSION: Sequential immunotherapy and targeted therapy provide clinically meaningful survival benefits for patients with BRAFV600-mutant melanoma.

Scientific data provide the evidence that secondary K-RAS mutations do not occur during anti-epidermal growth factor receptor therapy in colorectal cancer patients. This multicenter phase II prospective study aims to investigate the activity of a retreatment with a cetuximab-based therapy. We enrolled 39 irinotecan-refractory patients who had a clinical benefit after a line of cetuximab- plus irinotecan-based therapy and then a progression of disease for which underwent a new line chemotherapy and finally, after a clear new progression of disease, were retreated with the same cetuximab- plus irinotecan-based therapy. Median number of therapeutic lines before accrual was 4. Median interval time between last cycle of first cetuximab-based therapy and first cycle of the retreatment was 6 months. Overall response rate was 53.8% with 19 partial responses (48.7%) and 2 complete responses (5.1%). Disease stabilization was obtained in 35.9% of patients and progression in four patients (10.2%). Median progression-free survival was 6.6 months. The correlation between skin toxicity during first cetuximab therapy and during cetuximab rechallenge was significant (P = 0.01). Rechallenge with the same cetuximab-based therapy may achieve a new important clinical benefit further delaying the progression of disease and improving the therapeutic options.

Evidence suggests that metastatic colorectal carcinoma (mCRC) has a high level of intratumor heterogeneity. We carried out a quantitative assessment of tumor heterogeneity for KRAS, NRAS, BRAF and PIK3CA mutations, in order to assess potential clinical implications. Tumor samples (n = 182) from the CAPRI-GOIM trial of first-line cetuximab + FOLFIRI in KRAS exon-2 wild-type mCRC patients were assessed by next-generation sequencing that allows quantitative assessment of mutant genes. Mutant allelic frequency was normalized for the neoplastic cell content and, assuming that somatic mutations usually affect one allele, the Heterogeneity Score (HS) was calculated by multiplying by 2 the frequency of mutant alleles in neoplastic cells. Therefore, HS virtually corresponds to the fraction of neoplastic cells carrying a specific mutation. The KRAS HS ranged between 12 and 260 with mean value of 87.1 and median value of 84.4, suggesting that in most CRC, the majority of neoplastic cells carry mutant KRAS. Similar findings were observed for NRAS (HS range 35.5–146.7; mean 102.8; median 117.1). In contrast, in BRAF (HS range 17.1–120; mean 54.8; median 54.3) and PIK3CA (HS range 14.3–120; mean 59.5; median 47.3) mutant cases, only a fraction of neoplastic cells seem to carry the mutant allele. The response rate was 70% in KRAS mutant patients with an HS 33 patients (high KRAS; n = 35); median progression-free survival were 7.97 and 8.37 months, respectively. Low-KRAS tumors had a higher frequency of additional mutations in PIK3CA when compared with high-KRAS (6/10 versus 8/35). KRAS and NRAS mutations are usually present in the majority of neoplastic cells, whereas BRAF and PIK3CA mutations often affect a limited fraction of transformed cells. Resistance to cetuximab in low-KRAS patients might be driven by the complex mutational profile rather than KRAS mutation load.