Department of Dermatology, Nara Medical University School of Medicine, Kashihara, Japan.
Department of Pathology, Tokyo Metropolitan Cancer and Infectious Disease Center Komagome Hospital, Tokyo, Japan.
J Cutan Pathol. 2023 Aug;50(8):695-701. doi: 10.1111/cup.14401. Epub 2023 Feb 20.
Poromatosis is a rare condition characterized by the development of multiple poromas, mainly reported in patients with a history of malignancy. Recently, frequent YAP1::MAML2 and YAP1::NUTM1 fusions have been described in poromas and porocarcinomas. To date, the molecular features of poromatosis have been investigated in one patient only, wherein the poromas harbored YAP1::MAML2 fusions. Herein, we present two additional cases of poromatosis with YAP1::MAML2 fusions. Case 1: An 81-year-old woman presented with nine papules on the scalp, trunk, and extremities persisting for a year. She had a history of breast cancer, with no information on the treatment. Seven papules were excised. Case 2: A 65-year-old woman presented with 21 lesions on her trunk and lower extremities persisting for 2 years. She had been diagnosed with breast cancer 11 years prior and had undergone partial mastectomy, radiotherapy, chemotherapy, and endocrine therapy. Four lesions were excised. All 11 lesions in both patients were histopathologically similar: anastomosing cords and strands extending from the epidermis, and poroid and cuticular cell proliferation with interspersed small ducts. The tumors showed diffuse nuclear expression of YAP1 N-terminus and loss of YAP1 C-terminus expression. No lesions showed NUT immunopositivity. Sanger sequencing identified YAP1::MAML2 fusions in the poromas of both patients.
多发性汗管瘤病是一种罕见的疾病，其特征是多发性汗管瘤的发生，主要见于有恶性肿瘤病史的患者。最近，在汗管瘤和汗管癌中频繁描述了 YAP1::MAML2 和 YAP1::NUTM1 融合。迄今为止，仅在一名患者中研究了汗管瘤病的分子特征，其中汗管瘤存在 YAP1::MAML2 融合。在此，我们报告了另外两例具有 YAP1::MAML2 融合的汗管瘤病。病例 1：一名 81 岁女性因头皮、躯干和四肢的九个丘疹持续一年就诊。她患有乳腺癌，治疗情况不详。切除了 7 个丘疹。病例 2：一名 65 岁女性因躯干和下肢的 21 个病变持续 2 年就诊。她在 11 年前被诊断患有乳腺癌，并接受了部分乳房切除术、放疗、化疗和内分泌治疗。切除了 4 个病变。两名患者的所有 11 个病变在组织病理学上均相似：从表皮延伸的吻合性索和条带，以及汗管样和角质细胞增生，伴有穿插的小导管。肿瘤表现为 YAP1 N 末端弥漫核表达和 YAP1 C 末端表达缺失。没有病变表现出 NUT 免疫阳性。Sanger 测序在两名患者的汗管瘤中均鉴定出 YAP1::MAML2 融合。
