Breast conserving surgery versus mastectomy: The influence of comorbidities on choice of surgical operation in the department of defense health care system

Background: Studies on the effect of comorbidities on breast cancer operation have been limited and inconsistent. This study investigated whether pre-existing comorbidities influenced breast cancer surgical operation in an equal access health care system. Methods: This study was based on linked Department of Defense cancer registry and medical claims data. The study subjects were patients diagnosed with stage I to III breast cancer during 2001 to 2007. Logistic regression was used to determine if comorbidity was associated with operation type and time between diagnosis and operation. Results: Breast cancer patients with comorbidities were more likely to receive mastectomy (odds ratio [OR] = 1.27; 95% confidence interval [CI], 1.14 to 1.42) than breast conserving surgery plus radiation. Patients with comorbidities were also more likely to delay having operation than those without comorbidities (OR = 1.27; 95% CI, 1.14 to 1.41). Conclusions: In an equal access health care system, comorbidity was associated with having a mastectomy and with a delay in undergoing operation.