Wehkamp Ulrike, Pott Christiane, Unterhalt Michael, Koch Karoline, Weichenthal Michael, Klapper Wolfram, Oschlies Ilske
*Department of Dermatology †Medical Department II §Department of Pathology, Hematopathology Section, Christian-Albrechts-University Kiel, Kiel ‡Department of Internal Medicine III, University Hospital of Munich, Munich, Germany.
Am J Surg Pathol. 2015 Aug;39(8):1093-101. doi: 10.1097/PAS.0000000000000445.
Mantle cell lymphoma (MCL) is a B-cell neoplasm with a variable and generally aggressive clinical course. So far our knowledge of skin involvement of MCL is limited. To understand the clinical and histopathologic features of MCL with skin involvement, the files of the Lymph Node Registry Kiel were screened for MCL diagnosed in the skin. Over a period of 13 years, 1321 biopsy specimens were diagnosed as MCL; among them, 14 patients (1%) showed skin involvement. Of these, skin was the initial site of manifestation in 6/11 (55%) cases. One patient presented with a skin-limited lymphoma. Furthermore, 7/12 (58%) patients presented with lesions on the leg. The lymphomas were highly proliferative with blastoid cytology in 12/14 (86%) cases. Moreover, the immunophenotype with expression of BCL2 (100%), MUM-1/IRF4 (83%), and IgM (82%) and lack of CD10 (25%) and BCL6 (0%) closely resembled the features of primary cutaneous diffuse large B-cell lymphoma, leg type. Solely the expression of cyclin D1 (100%) and the presence of t(11;14) (100%) allowed a distinction from cases of primary cutaneous diffuse large B-cell lymphoma, leg type. Only 2 MCL cases with skin involvement presented with classical cytology. Interestingly, in these 2 cases skin involvement occurred simultaneously in a lesion of coexisting primary cutaneous marginal zone lymphoma. Our data suggest that clinical presentation on the leg and blastoid cytology along with high proliferation and expression of Bcl2, Mum-1/IRF4, and IgM are typical for MCL involving the skin. Lymphomas with these features might be erroneously diagnosed as diffuse large B-cell lymphoma, leg type, if cyclin D1 staining is not performed.
套细胞淋巴瘤（MCL）是一种B细胞肿瘤，临床病程多变且通常具有侵袭性。到目前为止，我们对MCL皮肤受累的了解有限。为了了解皮肤受累的MCL的临床和组织病理学特征，我们筛查了基尔淋巴结登记处诊断为皮肤MCL的病例档案。在13年的时间里，1321份活检标本被诊断为MCL；其中14例（1%）出现皮肤受累。在这些病例中，皮肤是6/11（55%）病例的首发部位。1例患者表现为皮肤局限性淋巴瘤。此外，7/12（58%）患者腿部出现病变。12/14（86%）病例中的淋巴瘤具有高度增殖性且细胞形态呈母细胞样。此外，免疫表型表现为BCL2（100%）、MUM-1/IRF4（83%）和IgM（82%）表达，而CD10（25%）和BCL6（0%）缺乏表达，这与原发性皮肤弥漫性大B细胞淋巴瘤（腿部型）的特征非常相似。仅细胞周期蛋白D1（100%）的表达和t(11;14)（100%）的存在可将其与原发性皮肤弥漫性大B细胞淋巴瘤（腿部型）区分开来。只有2例皮肤受累的MCL病例表现为典型细胞形态。有趣的是，在这2例病例中，皮肤受累同时出现在共存的原发性皮肤边缘区淋巴瘤的病变中。我们的数据表明，腿部临床表现、母细胞样细胞形态以及高增殖性和Bcl2、Mum-1/IRF4和IgM的表达是皮肤受累MCL的典型特征。如果不进行细胞周期蛋白D1染色，具有这些特征的淋巴瘤可能会被错误地诊断为原发性皮肤弥漫性大B细胞淋巴瘤（腿部型）。
