Purpose: Guideline-recommended treatment for stage II/III colorectal cancer includes postsurgical chemotherapy and/or radiation as standard of care. This study measures adherence to guidelines across 3 Canadian provinces and evaluates the relationship of patient characteristics with receiving standard care.
Patients and methods: All surgically treated patients diagnosed in 2004 with stage III colon or stage II/III rectal cancer and residing in Alberta, Saskatchewan, or Manitoba were identified from provincial cancer registries. Sex, age at diagnosis, and area of residence were also obtained from the cancer registry. The primary outcome of interest was receipt of standard care: surgery followed by chemotherapy or radiation therapy (adjuvant therapy). chi2 tests and binary regression with log link assessed the relationship of patient demographic characteristics (age, sex, residence, cancer disease stage) with receipt of standard care.
Results: About half of the patients received adjuvant therapy. Patients with stage III rectal cancer were more likely to receive adjuvant treatment than stage II patients in Alberta and Saskatchewan. There was a large decrease in the percentage of patients who received adjuvant treatment with increasing age in all the provinces (P < .001), ranging from about 80% of those aged < 65 years to about 20% of those aged >or= 75 years for colon cancer patients and from about 70% to 30%, respectively, for rectal cancer patients. The decrease of adjuvant treatment with increasing age was most marked in Alberta.
Conclusion: The percentage of patients receiving guideline-recommended treatment is low. Reasons for lack of adherence to guidelines need to be addressed.