Bevacizumab combined with capecitabine and oxaliplatin in patients with advanced adenocarcinoma of the small bowel or ampulla of vater: A single-center, open-label, phase 2 study

To evaluate the efficacy and safety of bevacizumab when added to first-line oxaliplatin-based chemotherapy (either capecitabine plus oxaliplatin [XELOX] or fluorouracil/folinic acid plus oxaliplatin [FOLFOX-4]) in patients with metastatic colorectal cancer (MCRC). Patients with MCRC were randomly assigned, in a 2 x 2 factorial design, to XELOX versus FOLFOX-4, and then to bevacizumab versus placebo. The primary end point was progression-free survival (PFS). A total of 1,401 patients were randomly assigned in this 2 x 2 analysis. Median progression-free survival (PFS) was 9.4 months in the bevacizumab group and 8.0 months in the placebo group (hazard ratio [HR], 0.83; 97.5% CI, 0.72 to 0.95; P = .0023). Median overall survival was 21.3 months in the bevacizumab group and 19.9 months in the placebo group (HR, 0.89; 97.5% CI, 0.76 to 1.03; P = .077). Response rates were similar in both arms. Analysis of treatment withdrawals showed that, despite protocol allowance of treatment continuation until disease progression, only 29% and 47% of bevacizumab and placebo recipients, respectively, were treated until progression. The toxicity profile of bevacizumab was consistent with that documented in previous trials. The addition of bevacizumab to oxaliplatin-based chemotherapy significantly improved PFS in this first-line trial in patients with MCRC. Overall survival differences did not reach statistical significance, and response rate was not improved by the addition of bevacizumab. Treatment continuation until disease progression may be necessary in order to optimize the contribution of bevacizumab to therapy.

Adenocarcinomas of the small bowel and ampulla of Vater represent rare cancers that have limited data regarding first-line therapy. We conducted a phase II trial to evaluate the benefit of capecitabine in combination with oxaliplatin (CAPOX) in patients with advanced adenocarcinoma of small bowel or ampullary origin. Eligible patients with metastatic or unresectable tumors and no prior systemic chemotherapy for advanced disease participated in this phase II trial. CAPOX was administered as a 21-day cycle with oxaliplatin 130 mg/m(2) on day 1 and capecitabine 750 mg/m(2) twice a day on days 1 through 14. The primary end point was overall response rate as assessed by Response Evaluation Criteria in Solid Tumors. Thirty-one patients were enrolled onto the study, and 30 patients received study treatment. The confirmed overall response rate was 50%; three patients with metastatic disease achieved complete responses. The median time to progression (TTP) was 11.3 months, and the median overall survival (OS) was 20.4 months. Subset analysis of patients with metastatic disease only (n = 25) revealed a median TTP of 9.4 months and median OS of 15.5 months. The most common grades 3 or 4 toxicities included fatigue (30%), peripheral neuropathy (10%), vomiting (10%), diarrhea (10%), and neutropenia (10%). When administered to patients with good performance status, CAPOX is well tolerated and produces a superior response rate and longer OS compared with other regimens in the literature. CAPOX should be considered a new standard regimen for advanced small bowel and ampullary adenocarcinomas.

Background: Despite having a dramatically larger surface area than the large intestine, the small intestine is an infrequent site for the development of adenocarcinoma. To better understand the molecular abnormalities in small bowel adenocarcinoma (SBA), we characterised a number of candidate oncogenic pathways and the immunophenotype of this rare cancer. Methods: Tissue microarrays were constructed from tumour samples from 54 patients with all stages of the disease. Immunohistochemistry and microsatellite instability (MSI) testing were conducted. Results: The profile of cytokeratin 20 and 7 coexpression was variable, but expression of caudal type homeobox transcription factor 2 (CDX2) was present in 70% of cases. In this young population (median age 54 years), loss of mismatch repair (MMR) proteins occurred in 35% of patients, with confirmed MSI in 100% of tested cases. Expression of vascular endothelial growth factor-A (VEGF-A) and epidermal growth factor receptor (EGFR) was common, occurring in 96 and 71% of patients, respectively. Only one case showed HER2 expression and none showed loss of phosphatase and tensin homologue mutated on chromosome 10 (PTEN). Conclusions: These results suggest that alterations in DNA MMR pathways are common in SBAs, similar to what is observed in large bowel adenocarcinomas. Furthermore, the high percentage of tumours expressing both EGFR and VEGF suggests that patients with this rare cancer may benefit from therapeutic strategies targeting EGFR and VEGF receptor (VEGFR).