Abstract: A predictive model of nipple-areola complex involvement for indicating nipple-sparing mastectomy in immediate breast reconstruction patients        XU Yuan-bing*, HUANG Xiao-yan, CHEN Jia-jian, et al.*Department of Breast Surgery, Fudan University Shanghai Cancer Center and Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032,China
Corresponding author: WU Jiong, E-mail:wujiong1122@vip.sina.com
Abstract    Objective    To explore the relative risk factors of nipple-areola complex (NAC) involvement in immediate breast reconstruction after nipple-sparing mastectomy (NSM+IBR), and develop a clinical predictive model. Methods The clinical features, imaging and pathological features of 474 cases who received NSM +IBR between January 2017 and August 2019 at Fudan University Shanghai Cancer Center were analyzed retrospectively. Patients were divided into NAC positive group and NAC negative group according to the postoperative paraffin pathology of NAC. Univariate and multivariate analyses were conducted to identify predictive factors, and the corresponding predictive model was established and verified. Results    In 474 cases, the positive rate of NAC was 13.71% (65/474). Univariate analysis revealed that tumor location, nipple discharge, nipple retraction, eczema-like changes in the skin of NAC, clinical tumor size, tumor-nipple distance, clinical lymph node status, vascular invasion, MG NAC calcification, malignant characteristic calcification, concomitant carcinoma in situ, histologic type, histological grade, subtype were associated with occult NAC involvement. By logistical regression analysis, nipple bloody discharge, nipple retraction, eczema-like changes in the skin of NAC, clinical tumor size, TND, clinical lymph node status, vascular invasion were determined to be the independent predictors of nipple involvement. The development of PI-NAC (predictive index of NAC) model suggested that 0 to 1 was classified as low risk of NAC involvement, 2 to 4 as intermediate risk, and 5 or more as high risk. The AUC value of the model internally verified ROC curve was 0.85 (95%CI: 0.80-0.89). A significant correlation was observed between the predictive factors and NAC involvement. Conclusion    Nipple bloody discharge, nipple retraction, eczema-like changes in the skin of NAC, clinical tumor size, TND, clinical lymph node status, vascular invasion were important independent indicators of NAC involvement. The predictive model is helpful to evaluate the safety of nipple-areola complex involvement in the preoperative period.

Key words: nipple-sparing mastectomy, immediate breast reconstruction, nipple-areolar complex involvement, predictive model

摘要： 目的    探讨保留乳头乳晕复合体乳房切除术（NSM）联合即刻乳房重建手术（IBR）手术中乳头乳晕复合体（NAC）安全性保留的相关危险因素，并建立预测模型。方法    回顾性分析2017年1月至2019年8月在复旦大学附属肿瘤医院乳腺外科行NSM联合IBR的474例病人的临床资料。依据乳头后方组织术后石蜡病检结果进行病例分组即NAC（+）组与NAC（-）组。分析两组病人的临床、影像及病理学特征，进行多因素分析，对独立预测指标赋值，计算不同分值的NAC阳性率，建立相应预测模型并验证。结果    474例病例中，NAC阳性率为13.71%（65/474），单因素分析显示肿瘤位置、乳头溢液、乳头凹陷、NAC皮肤湿疹样改变、临床肿瘤大小、肿瘤至乳头距离（TND）、临床淋巴结状态、MG-乳头后方钙化、恶性特征钙化灶、合并原位癌成分、组织学类型、组织学分级、脉管癌栓、分子分型与NAC肿瘤阳性相关。多因素分析显示乳头血性溢液、乳头凹陷、NAC皮肤湿疹样改变、临床肿瘤大小、TND、临床淋巴结状态、脉管癌栓是NAC肿瘤阳性独立预测指标。建立NAC预测指数（Predictive Index of NAC，PI-NAC）预测模型提示，0～1分为NAC肿瘤累及低风险，2～4分为中风险，5分及以上为高风险。该模型内部验证ROC曲线AUC值0.85（95%CI 0.80-0.89），具有较好预测效能。结论    乳头血性溢液、乳头凹陷、NAC皮肤湿疹样改变、临床肿瘤大小、TND、临床淋巴结状态、脉管癌栓是NAC受累的重要独立指标。预测模型有助于术前更好地评估NSM的肿瘤安全性。

关键词: 保留乳头乳晕乳房切除术, 即刻乳房重建, 乳头乳晕复合体浸润, 预测模型