Circular tumor growth: a prognostic factor in stage II colorectal carcinoma.

Background/Aims: Almost all patients with stage II colorectal cancer are spared adjuvant chemotherapy, yet a considerable number of these patients die from the disease. The aim of this retrospective study was to identify factors negatively affecting survival of patients with stage II colorectal cancer treated by curative resection. Methodology: Study subjects were 88 patients who had undergone curative resection for stage II colorectal cancers at Miyazaki University Hospital during the period from 1987-1999. Patients were followed up for a minimum of 5 years or until death. The influence of clinical and pathologic variables on 5-year cancer-specific survival was assessed by uni variate and multivariate analyses. Results: The 5-year cancer-specific survival rate was 83.4%. Univariate analysis showed circular tumor growth to be significantly associated with decreased survival (p=0.0047). Furthermore, multivariate analysis showed that circular tumor growth significantly affected long-term cancer-specific survival of patients with stage II colorectal cancer (hazard ratio 1.184, p=0.025). Conclusions: Circular tumor growth is an independent prognostic factor for patients with stage II colorectal cancer. The long-term prognosis of stage II colorectal cancer patients with circular-type carcinoma appear to be poor.