Abstract
BACKGROUND.
It is unclear how noncancer conditions affect the use or effectiveness of adjuvant therapy among older patients with colon cancer.
METHODS.
The authors conducted a cohort study of older patients with stage III colon cancer who were diagnosed from 1993 to 1999 in the Surveillance, Epidemiology, and End ResultsโMedicare database. The correlations between receipt of adjuvant chemotherapy and heart failure, diabetes, and chronic obstructive pulmonary disease (COPD) were assessed. Multivariable regression analysis was used to assess the risk of death and hospitalization as a function of treatment and comorbidity status.
RESULTS.
The study sample consisted of 5330 patients (median age, 76 years). The use of adjuvant therapy was related significantly to heart failure (36.2% vs 64.9% of patients with vs without heart failure, respectively; adjusted odds ratio [OR], 0.49; 95% confidence interval [95% CI], 0.40โ0.60). More moderate correlations were observed for COPD (OR, 0.83; 95% CI, 0.70โ0.99) and diabetes (OR, 0.81; 95% CI, 0.68โ0.97). Among patients who had heart failure, the 5โyear survival was significantly higher among those who received adjuvant chemotherapy (adjusted 5โyear survival rate, 43%; 95% CI, 40โ47%) than among those who did not receive adjuvant chemotherapy (30%; 95% CI, 27โ34%). Among patients without heart failure, the 5โyear survival estimates among treated and untreated patients were 54% (95% CI, 52โ56%) and 41% (95% CI, 38โ44%), respectively. The probability of allโcause, conditionโspecific, or toxicityโrelated hospitalization associated with adjuvant therapy was not altered by the presence of any of the 3 conditions.
CONCLUSIONS.
Although chronic conditions appeared to be a strong barrier to the receipt of adjuvant chemotherapy, adjuvant therapy appeared to provide a significant survival benefit to patients who had colon cancer with the conditions studied. Cancer 2007. ยฉ 2007 American Cancer Society.