Breast Cancer Found Incidentally After Reduction Mammaplasty in Young Insured Women.

[BACKGROUND] Reduction mammaplasty is a common operation performed for healthy women. The estimated incidence of breast cancer diagnosed at the time of reduction mammaplasty varies from 0.06 to 4.5%, and information on the care of these patients is limited. This study aimed to determine the incidence of breast cancer identified incidentally during reduction mammaplasty and to characterize preoperative imaging.

[METHODS] Women 18 years of age or older who underwent reduction mammaplasty from 2013 to 2015 were identified from the Truven Health MarketScan Research Databases. Patients with prior breast cancer were excluded. Descriptive statistics were calculated for patient characteristics, incidental breast cancer, preoperative breast imaging, and postoperative treatment.

[RESULTS] Reduction mammaplasty was performed for 18,969 women with a mean age of 42.5 years. Of these patients, 186 (0.98%) were incidentally found to have breast cancer, with 134 (0.71%) having invasive breast cancer and 52 (0.27%) having carcinoma in situ. The patients with incidentally found cancer were older than the patients without cancer (50.8 vs. 42.5 years; p < 0.001). Overall, 58.2% of the patients had undergone mammography before reduction mammoplasty. The rates were higher (> 80%) for the patients older than 40 years. Preoperative mammography was performed for 76.3% of those with a diagnosis of breast cancer at time of reduction mammoplasty.

[CONCLUSIONS] Breast cancer diagnosed incidentally at the time of reduction mammaplasty is uncommon and often radiographically occult. The majority of women older than 50 years appropriately received preoperative mammography. These data can be used to manage patient expectations about the potential for the incidental diagnosis of breast cancer at reduction mammaplasty, even with a negative preoperative mammography.