Pellegrino Benedetta, Mazzaschi Giulia, Madeddu Denise, Mori Cristina, Lagrasta Costanza Anna Maria, Missale Gabriele, Quaini Federico, Musolino Antonino
Medical Oncology and Breast Unit, University Hospital of Parma, Parma, Italy.
Department of Medicine and Surgery, University of Parma, Parma, Italy.
Front Oncol. 2020 Feb 25;10:192. doi: 10.3389/fonc.2020.00192. eCollection 2020.
A patient with HER2-positive early breast cancer (BC) developed dermatomyositis (DM), which disappeared after the first administration of adjuvant trastuzumab. No HER2 overexpression/amplification was observed in DM skin biopsies. Both BC and skin immune infiltrates were composed mostly of CD3+ T-lymphocytes. Interestingly, tumor-infiltrating lymphocytes expressed PD-1, which was negligible in skin-infiltrating lymphocytes, while both BC cells and keratinocytes were PD-L1-positive. High serum levels of endogenous anti-HER2 antibodies were detected, confirming the induction of a HER2-specific adaptive immune response. It may be argued that HER2-specific T-lymphocytes cross-reacted with one or more unknown skin antigens, causing DM. Trastuzumab may have silenced skin cross-reaction by eliminating any residual HER2-positive micrometastatic disease and, thus, inducing DM remission.
一名HER2阳性早期乳腺癌（BC）患者发生了皮肌炎（DM），在首次给予辅助曲妥珠单抗后DM消失。在DM皮肤活检中未观察到HER2过表达/扩增。BC和皮肤免疫浸润均主要由CD3 + T淋巴细胞组成。有趣的是，肿瘤浸润淋巴细胞表达PD-1，而在皮肤浸润淋巴细胞中可忽略不计，而BC细胞和角质形成细胞均为PD-L1阳性。检测到高血清水平的内源性抗HER2抗体，证实诱导了HER2特异性适应性免疫反应。可以认为，HER2特异性T淋巴细胞与一种或多种未知皮肤抗原发生交叉反应，导致了DM。曲妥珠单抗可能通过消除任何残留的HER2阳性微转移病灶，从而诱导DM缓解，使皮肤交叉反应沉默。
