Factors associated with use of preoperative chemoradiation therapy for rectal cancer in the Cancer Care Outcomes Research and Surveillance Consortium.

PURPOSE: Preoperative (preop) chemoradiation therapy (CRT) improves local control and reduces toxicity more than postoperative (postop) CRT for the treatment of stages II/III rectal cancer, but studies suggest that many patients still receive postop CRT. We examined patient beliefs and clinical and provider characteristics associated with receipt of recommended therapy.

METHODS: We identified stages II/III rectal cancer patients who had primary site resection and CRT among subjects in the Cancer Care Outcomes Research and Surveillance Consortium, a population-based and health system-based prospective cohort of newly diagnosed colorectal cancer patients from 2003 to 2005. Patient surveys and abstracted medical records were used to construct variables and determine sequence of CRT and surgery. Logistic regression was used to model the association between predictors and receipt of preop CRT.

RESULTS: Of the 201 patients, 66% received preop and 34% received postop CRT. Those visiting a medical oncologist and/or radiation oncologist before a surgeon had a 96% (95% confidence interval, 92%-100%) predicted probability of receiving preop CRT, compared with 48% (95% confidence interval, 41%-55%) for those visiting a surgeon first. Among those visiting a surgeon first, documentation of recommended staging procedures was associated with receiving preop CRT.

CONCLUSIONS: Sequence of provider visits and documentation of recommended staging procedures were important predictors of receiving preop CRT. Initial multidisciplinary evaluation led to better adherence to CRT guidelines. Further evaluation of provider characteristics, referral patterns, and related health system processes should be undertaken to inform targeted interventions to reduce variation from recommended care.