Women with Lynch syndrome (LS) have a high risk of developing endometrial carcinoma (EC) and, less frequently, ovarian carcinoma. As EC not uncommonly is the first malignancy, prophylactic hysterectomy (PH) has been increasingly implemented. In this study, we report the clinicopathologic features of a series of 70 LS patients who underwent either PH (n=39) or nonprophylactic hysterectomy (NPH) (n=31) at 3 tertiary referral centers. Among the 39 patients with PH, 2 had endometrial tumors seen grossly, whereas 37 showed no macroscopic lesions. Total inclusion of the endometrium was performed in 24/39 (61.5%). Abnormal histologic findings were identified in 9/39 (23.1%) PHs: 3 endometrial endometrioid carcinomas (EECs), including the 2 macroscopic and 1 microscopic (0.6 cm), and 4 atypical and 6 nonatypical hyperplasias. NPH included those performed for endometrial and ovarian cancer treatment. Tumor sampling followed standard protocols. ECs comprised 26 EECs and 1 clear cell carcinoma, with a median size of 3.7 cm. Hyperplasia was observed in 10 (33.3%) as background in EC, in 4 showing atypia. Eight (29.6%) tumors were centered in the lower uterine segment (all EECs). EECs were predominantly well differentiated (53.8%) and FIGO stage I (77.8%). A papillary architecture was common (51.9%) and associated with microcystic elongated and fragmented foci in 4. Mucinous differentiation was observed in 25.9% of endometrial tumors, typically representing <10%. Most endometrial tumors (81.5%) showed tumor-infiltrating lymphocyte counts ≥42/10 high-power fields. Four tumors showed extensive necrosis. Eight patients had ovarian tumors (4 synchronous), including 2 endometrioid carcinomas, 2 clear cell carcinomas, 1 borderline clear cell adenofibroma, 1 Müllerian carcinoma of mixed cell types, 1 primitive neuroectodermal tumor, and 1 metastatic melanoma. Total inclusion of the endometrium should be done in all LS patients' surgical specimens without macroscopic lesions as some of these patients harbor preneoplastic or neoplastic conditions treatable at an early stage. The phenotype of LS-associated endometrial and ovarian tumors is variable and frequently includes features not commonly observed in sporadic cancers, but in our experience carcinomas were in general low grade and low stage.
Lynch 综合征 (LS)女性发生子宫内膜癌(EC)的风险较高，其次发生卵巢癌的风险也高。因为EC常为首发恶性肿瘤，所以预防性子宫切除已越来越多。
9/39 (23.1%) 例PHs有异常组织学发现：3例子宫内膜子宫内膜样癌(EECs)，包括2例大体可见和1例镜下癌(0.6 cm)，4例非典型性和6例无非典型性增生。NPH包括因子宫内膜和卵巢癌治疗切除的病例。肿瘤取材遵循标准方案。ECs病例包括26例EECs和1例透明细胞癌，中位大小3.7cm。EC中，10 (33.3%)例可见增生背景，4例显示非典型性。8(29.6%)例肿瘤位于子宫下段（全部为EECs）。EECs大部分为高分化(53.8%)，FIGO I 期(77.8%)。乳头状结构常见(51.9%)，4例伴微囊拉长和碎片状病灶。25.9%的子宫内膜肿瘤可见粘液分化，典型区域<10%。大部分子宫内膜肿瘤(81.5%)显示肿瘤浸润性淋巴细胞计数≥42/10HPF。4例肿瘤出现广泛坏死。8名患者有卵巢肿瘤（4例为同时性），包括2例子宫内膜样癌，2例透明细胞癌，1例交界性透明细胞腺纤维瘤，1例混合细胞型苗勒氏癌，1例原始神经外胚层肿瘤和1例转移性黑色素瘤。