Abstract P2-15-09: Impact of neoadjuvant chemotherapy on the short- and long-term outcomes in patients who underwent immediate breast reconstruction after mastectomy

Background and Purpose In breast cancer patients receiving neoadjuvant chemotherapy (NAC), the use of immediate breast reconstruction (IBR) as a breast cancer treatment option remains controversial. The Japanese breast cancer society conducted retrospective multicenter cohort study in the era of IBR, and we assessed the impact of NAC on surgical and oncological outcomes in patients underwent IBR. Methods Between January 2008 and December 2016, 473 (10.0%) breast cancer cases received NAC of 4726 cases underwent IBR after mastectomy. The clinicopathological and survival data of patients who received NAC (the NAC group) and those who did not receive NAC (the control group) were compared in terms of postoperative complications (infection, hemorrhage, seroma, dehiscence, tissue expander or implant loss, flap or skin necrosis) and oncologic safety. Results Eight-hundred forty cases had minor or major complications. NAC did not increase the risk of complications after IBR (OR 1.20; 95%CI 0.95 - 1.53; p = 0.13). Smoking (OR 1.35; 95%CI 1.14 - 1.62; p = 0.001), overweight (BMI25≤) (OR 1.94; 95%CI 1.61 - 2.35; p < 0.001), PMRT (OR 1.54; 95%CI 1.20 - 1.99; p = 0.01) increased risk of complications. At the median follow-up time of 76.5 months, 36 patient (7.6%) in the NAC group and 147 patients (3.5%) in the control group had local recurrence. 35 patient (7.4%) in the NAC group and 147 patients (2.0%) in the control group had reginal recurrence. Conclusion Immediate breast reconstruction after NAC is a safe procedure with post-operative complication profile. It can be performed safely and therefore should be considered as a strategy preferred for patients with local advanced breast cancer. Citation Format: Hiroko Nogi, Akiko ogiya, Naoto Kondo, Makoto Ishitobi, Chikako Yamauchi, Hiroki Mori, Ayaka Shimo, Kazutaka Narui, Naomi Nagura, Hirohito Seki, Shinsuke Sasada, Teruhisa Sakurai, Tadahiko Shien. Impact of neoadjuvant chemotherapy on the short- and long-term outcomes in patients who underwent immediate breast reconstruction after mastectomy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-15-09.