Abstract P3-21-01: A higher locoregional recurrence rate of nipple areolar complex sparing mastectomy with immediate implant reconstruction

Abstract

Abstract Background The rate of Nipple Areolar Complex (NAC) sparing mastectomy with implant reconstruction is rapidly increasing as the Korean National Health Insurance reimbursed reconstructive surgery for breast cancer patients from 2015. However, only a few reports about oncologic safety have been reported in the absence of large-scale data. We have analyzed the oncologic outcomes of all consecutive breast cancer patients who had NAC sparing mastectomy with immediate implant reconstruction. Methods We used the data from prospectively collected clinical data of patients who underwent immediate implant reconstruction after NAC sparing mastectomy at the National Cancer Center between January 2012 and December 2017. Demographics, clinicopathological characteristics and the follow-up results were analyzed. The statistical analysis was done to infer relations between risk factors and oncologic outcomes such as death, distant metastasis or locoregional recurrence. Results: A total of 538 breasts was analyzed in 486 patients. The mean age of the patients was 44.6 years. The mean BMI was 22.48 kg/m2. The number of bilateral cases was 52 (10.7%) and 135 patients (27.8%) had multiple tumors. Median follow-up was 4.5 years. Molecular subtypes were 373 HR(+)/HER2(-) (69.3%), 31 HR(+)/HER2(+) (5.8%), 76 HR(-)/HER2(+) (14.1%) and 35 HR(-)/HER2(-) (6.5%). Chemotherapy was performed in a total of 212 (43.6%) patients, of which 68 (32.1%) were neoadjuvant and 144 (67.9%) were adjuvant purposes. Trastuzumab was administered to 53 (10.9%) of patients whose tumor size are larger than 1cm under guideline of reimbursement. Postoperative radiotherapy was performed in 131 patients (26.9%). Distant metastasis occurred in 20 patients (3.7%), and seven (1.4%) died. Locoregional recurrence occurred in 43 cases (8.0%) of 538 breasts, including 14 nipples (2.6%) and 12 subareolar lesions (2.2%). Analyzing risk factors related to locoregional recurrence, HR(-)/HER2(+) type showed the highest incidence of 11/76 (14.7%) among four subtypes. The incidence was statistically significantly lower in the group that received postmastectomy radiotherapy than in the group that did not. (6/131 (4.6%) vs 37/355 (10.4%), p=0.001). The node negative group who did not have postmastectomy radiotherapy (31/377 (8.2%)) showed a numerically higher incidence than the node positive group (8/121 (6.6%)). Conclusion Our results showed that NAC sparing mastectomy with immediate implant reconstruction had similar oncologic outcome in terms of overall survival or distant metastasis, however the locoregional recurrence was rather high. Even this is remediable problems we would admit that NAC sparing mastectomy is a bit different from traditional mastectomy. In case that we inevitably apply this operation to relatively young women with multifocal breast cancer, careful consideration would be needed. In addition, identifying risk factors of locoregional recurrence and tailored post-operative radiation therapy are expected to improve the disease-free survival of breast cancer. Citation Format: Ji Young You, Eun-Gyeong Lee, Soo Jin Park, Byeong Nam Kim, Seeyoun Lee, Eun Sook Lee, So-Youn Jung, Youngmi Kwon, Yun Ju Kim, Chan Wha Lee, Tae Hyun Kim. A higher locoregional recurrence rate of nipple areolar complex sparing mastectomy with immediate implant reconstruction [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-21-01.