Prognosis of small bowel adenocarcinoma treated with Mayo or Xelox regimen: a matched case-control study from a database of 581 patients with colorectal cancer.

The purpose of this study was to compare the effects of chemotherapy on the prognosis for patients with adenocarcinoma of the small bowel (SBC) and colorectal cancer (CRC). A case-control study was conducted, comprised of 13 SBC cases treated palliatively (n=7) following surgery with capecitabine monotherapy (Xeloda) combined with oxaliplatin (Xelox), or with adjuvant 5-fluorouracil chemotherapy (Mayo) (n=6). The control group was selected from a database of 581 patients with CRC, with each SBC case being matched to 5 CRC controls. In the palliative group, response rates (RR) for SBC patients were 14%, compared to 35% for CRC patients (p=0.08). Median progression-free survival (PFS) times were 4 and 6 months (p=0.8) and median overall survival (OS) times were 8.4 and 16.4 months (p=0.9) for SBC and CRC patients, respectively. In the adjuvant group, the recurrence-free survival rates were 66 and 89% (p=0.6) after 1 year and 66 and 71% (p=0.7) after 3 years. Three-year overall survival rates were 80 and 80% (p=0.3) in the palliative group, and 80 and 66% (p=0.4) in the adjuvant group. Standard chemotherapy regimes seemed less effective on SBC than on CRC patients, and had a less favorable prognosis. However, reliable conclusions cannot be drawn from a small patient population, and multicentre studies are needed.