The role of the surgeon in whether patients with lymph node-positive colon cancer see a medical oncologist.

BACKGROUND: Chemotherapy improves survival for patients with stage III colon cancer, but some older patients with lymph node-positive colon cancer do not see a medical oncologist and, thus, do not receive adjuvant chemotherapy.
METHODS: To evaluate the role of the surgeon in determining referrals to medical oncology among patients with stage III colon cancer, the authors conducted a retrospective cohort study of 6158 patients aged >or=66 years who were diagnosed with stage III colon cancer from 1992 through 1999 by using the Surveillance, Epidemiology, and End Results-Medicare linked database. Multilevel analysis was used to simultaneously model variations in patients' seeing a medical oncologist at the patient and surgeon levels.
RESULTS: Twenty-one percent of the total variance in seeing a medical oncologist was attributable to the surgeon after adjusting for available patient, tumor, and surgeon characteristics. The individual surgeon characteristics that significantly predicted whether the patient saw a medical oncologist were year since graduation (<or=10 years vs >20 years; hazard ratio [HR], 1.60; 95% confidence interval [95% CI], 1.19-2.16), practicing in a teaching hospital (yes vs. no: HR; 1.30; 95% CI, 1.07-1.58), and volume of patients with colon cancer (<30 patients vs >or=121 patients; HR, 0.66; 95% CI, 0.46-0.94). Surgeon sex, race, board certification, and type of practice were not independent predictors of medical oncology referral.
CONCLUSIONS: Surgeons accounted for approximately 20% of the variation in patients seeing a medical oncologist. Interventions at the level of the surgeon may be appropriate to improve the care of patients with colon cancer.