Prognostic factors of overall survival for patients with stage II colon cancer.

OBJECTIVE To analyze factors influencing survival of patients with stage II colon cancer treated at our cancer center (Sparrow Hospital) from February 1996 through December 2006. PATIENTS AND METHODS Survival analyses on 197 patients' age 71.1±0.9 years (29 to 97) were done using SAS system (V9.3, Cary NC). Analysis included age, gender, stage, surgery type, number of examined lymph nodes, pathological grade, tumor size and the use of adjuvant chemotherapy. RESULTS Mean follow up length was 48.1±2.3 months (0.1-133) and 56±3.3 (0.2-133) for survivors. The average number of removed lymph nodes was 18±13 (1-103). Adjuvant chemotherapy treatment (5-FU± leucovorin) was given to 49 patients, while others (148) were followed expectantly. There were 90 deaths during follow up. Only age exhibits a statistically significant relationship to survival (Hazard Ratio (HR) =1.06, 95% CI=1.03-1.08, p<0.001). Adjuvant chemotherapy possibly reduced the risk of death by 42% approaching a borderline advantage for survival (HR=0.58, CI=0.33-1.03, p=0.06. The number of removed lymph nodes also showed a possible relationship to survival (HR=0.98, CI= 0.62-1.56, p=0.07). Other investigated factors (gender, type of surgery, etc.) were not significant correlates. CONCLUSION In this study we found that the most important factor for survival of patients with Stage II colon cancer is the patient's age. Adjuvant chemotherapy showed a borderline significance while the number of resected lymph nodes seemed to be an important survival factor. However, in our study statistical significance was not achieved.