Wolffian tumor and its nosologic relative, the recently defined STK11 adnexal tumor are rare neoplasms thought to arise from mesonephric remnants. These tumors typically arise in the broad ligament, fallopian tube, and ovarian hilum and although most are associated with a good prognosis, up to 50% of STK11 adnexal tumors demonstrate aggressive clinical behavior. The chief differential diagnoses include endometrioid adenocarcinoma and sex cord stromal tumors. However, the morphologic and immunohistochemical features of these tumors exhibit considerable overlap with peritoneal mesothelioma. To fully characterize their immunophenotypic signature, we examined a total of 21 cases (18 Wolffian and 3 STK11 adnexal tumors) with standard markers used in the diagnosis of mesothelioma. Morphologic and immunohistochemical (IHC) features were reviewed and additional IHC performed for cases with available material. Patient age ranged from 25 to 73 (mean: 51) years. Sites included adnexa/broad ligament (6, 28%), paratubal (5, 24%), ovary/paraovarian (5, 24%), tubal (intraluminal) (2, 9.5%), pelvis (2, 9.5%), and liver (1, 5%). The mean tumor size was 9.3 cm (range: 0.2 to 22 cm). The histomorphology in most cases (14/21, 66%) consisted of tubular to solid sheets of neoplastic cells lined by columnar to cuboidal cells containing uniform round to oval nuclei. Compressed tubules with slit-like lumens and sieve-like pattern were also seen in at least 7 (33%) cases. Three cases demonstrated interanastomosing cords and trabeculae of epithelioid cells with cribriform and microacinar patterns growing within prominent myxoid stroma as described in STK11 adnexal tumors. In the cases with available IHC for 3 mesothelial markers (calretinin, WT1, D2-40), 55.5% (5 of 9) showed reactivity with all 3 markers. In cases with at least 2 available mesothelial markers, 69% (11/16) were positive for 2 markers (mostly calretinin and WT1). Claudin-4, MOC31, and BER-EP4 were negative in most cases tested (78% [7/9], 71.4% [5/7], and 100% [6/6], respectively). Given the resemblance to mesothelioma, there was initial strong consideration and/or actual misdiagnosis of mesothelioma in 3 cases (14%). In summary, the morphologic and immunohistochemical features of Wolffian tumor and its recently defined relative, STK11 adnexal tumor, can lead to misdiagnosis of mesothelioma, particularly when encountered in the disseminated or metastatic setting. Wolffian tumor and STK11 adnexal tumor should be considered in the differential diagnosis of all pelvic and peritoneal mesotheliomas.

中文翻译：

---

可能起源于沃尔夫的女性附件肿瘤（沃尔夫肿瘤）：腹膜间皮瘤的潜在模仿者。


沃尔夫肿瘤及其疾病相关的最近定义的 STK11 附件肿瘤是罕见的肿瘤，被认为是由中肾残余产生的。这些肿瘤通常出现在阔韧带、输卵管和卵巢门，尽管大多数与良好的预后相关，但高达 50% 的 STK11 附件肿瘤表现出侵袭性的临床行为。主要鉴别诊断包括子宫内膜样腺癌和性索间质瘤。然而，这些肿瘤的形态学和免疫组织化学特征与腹膜间皮瘤有相当大的重叠。为了充分表征其免疫表型特征，我们使用用于诊断间皮瘤的标准标记物检查了总共 21 个病例（18 个 Wolffian 肿瘤和 3 个 STK11 附件肿瘤）。对形态学和免疫组织化学 (IHC) 特征进行了审查，并对具有可用材料的病例进行了额外的 IHC。患者年龄从 25 岁到 73 岁（平均 51 岁）不等。部位包括附件/阔韧带 (6, 28%)、输卵管旁 (5, 24%)、卵巢/卵巢旁 (5, 24%)、输卵管（管腔内）(2, 9.5%)、骨盆 (2, 9.5%)、和肝脏 (1, 5%)。平均肿瘤大小为 9.3 cm（范围：0.2 至 22 cm）。大多数病例（14/21，66%）的组织形态由管状至实心的肿瘤细胞片组成，内衬柱状至立方形细胞，含有均匀的圆形至椭圆形细胞核。至少 7 例 (33%) 病例中还观察到具有狭缝状管腔和筛状图案的受压小管。三个病例显示，如 STK11 附件肿瘤中所述，在突出的粘液样基质内生长有筛状和微腺泡图案的上皮样细胞的吻合索和小梁。在具有 3 种间皮标记物（钙视网膜蛋白、WT1、D2-40）可用 IHC 的病例中，55。5%（9 人中的 5 人）表现出与所有 3 个标记物的反应性。在至少有 2 种可用间皮标记物的病例中，69% (11/16) 的 2 种标记物呈阳性（主要是钙视网膜蛋白和 WT1）。在大多数测试病例中，Claudin-4、MOC31 和 BER-EP4 呈阴性（分别为 78% [7/9]、71.4% [5/7] 和 100% [6/6]）。鉴于与间皮瘤的相似性，有 3 例病例 (14%) 最初被强烈考虑和/或实际误诊为间皮瘤。总之，沃尔夫肿瘤及其最近定义的相关 STK11 附件肿瘤的形态学和免疫组织化学特征可能导致间皮瘤的误诊，特别是在播散性或转移性环境中遇到时。所有盆腔和腹膜间皮瘤的鉴别诊断均应考虑沃尔夫肿瘤和 STK11 附件肿瘤。