Clinicopathological predictive factors for ipsilateral and contralateral events following initial surgery to treat ductal carcinoma in situ

BACKGROUND: Ipsilateral breast tumor recurrence (IBTR) after partial breast resection and contralateral breast tumor recurrence (CBTR) have been shown to occur relatively frequently in patients with ductal carcinoma in situ (DCIS). However, there is only limited data from Japanese institutes to support this. METHODS: Of 301 consecutive DCIS patients, 179 patients underwent a mastectomy, and the other 122 underwent partial resection in the National Cancer Center Hospital, Tokyo, with a median follow-up period of 2,106 days. We reviewed clinicopathological parameters including age, menopausal status, body mass index, family history (FH) of breast cancer, tumor size, histological subtype, nuclear grade (NG), hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status, treatment, and the surgical margin status of partially resected specimens. The risk associated with each of these parameters for IBTR in 122 patients who underwent partial resections, and for CBTR in a total of 301 patients were calculated using Cox proportional hazard general linear models. RESULTS: Of the 122 patients who underwent partial breast resection, IBTR occurred in 7 (5.7 %). The risk of IBTR was higher or tended to be higher in younger patients or those with lower NG tumors, but did not change significantly with respect to margin status or irradiation. Amongst the entire cohort of 301 patients, CBTR occurred in 18 cases (6.0 %). CBTR occurred significantly more frequently in patients with a FH of breast cancer and with HR+/HER2− subtype tumors by univariate analyses, and tumor subtype was an independent risk factor for CBTR by multivariate analysis. CONCLUSIONS: The local recurrence rate was low following partial resection of DCIS. Younger age was a risk factor for IBTR, whereas the HR+/HER2− tumor subtype and a FH of breast cancer were risk factors for CBTR.