(ChemotherapyAdvisor) – Histologic G3 grade and mucinous histotype colon adenocarcinomas are associated with poorer outcomes among patients with stage-II colon cancer, according to a single-institution study published in the International Journal of Colorectal Disease.
Adding adjuvant chemotherapy to radical surgical resection of stage-II colon cancer did not improve patients’ 5-year survival rates, but a trend was identified toward better prognosis associated with higher numbers of lymph nodes recovered in surgery, reported lead author Roberto Biffi, MD, Division of Abdomino-Pelvic and Minimally Invasive Surgery at the European Institute of Oncology in Milan, Italy, and colleagues.
“(O)ur retrospective analysis of a large consecutive monocentric series of pT3 N0 colon cancer patients who underwent radical colectomy confirms the association between lymph node recovery and outcome,” the authors wrote. The risk of tumor-specific deaths was inversely proportion to the number of dissected lymph nodes, “even over 20 up to about 25 lymph nodes,” they reported.
Adjuvant chemotherapy for stage-II colon cancer is controversial, and efforts are under way to identify clinical and pathological variables that predict prognosis.
The authors retrospectively studied data for 137 patients treated for pT3 N0 colon adenocarcinomas between 2000 and 2005. Adjuvant chemotherapy was not associated with survival, they found. Neither was patient age, gender, ASA score, body-mass index, multifocality, site of colon neoplasm, or perivascular invasion, they wrote.
“Only histological grade III and mucinous histotype were found to impact on cumulative incidence of colon-related events (P=0.03 and 0.02, respectively),” the authors reported. “The number of analyzed lymph nodes emerged as a factor possibly affecting cumulative incidence of colon-related events (P=0.09) as well as the cumulative incidence of colonic neoplasm recurrence-related deaths (P=0.10).”
Risk of colon-related events was inversely proportional to the number of dissected lymph nodes, the authors noted.
“Given the results, efforts to improve lymph node evaluation should result in clinically significant improvements in outcome, and also the quality of care, for patients with radically resected stage-II colon cancer,” the authors wrote.