Rash is one of the commonly observed adverse events with brentuximab vedotin (BV), a CD30-targeted antibody-drug conjugate used to treat cutaneous T-cell lymphoma (CTCL). However, clinical and histopathologic characterization of BV-associated rash (BVAR) is limited. Distinguishing BVAR from a patient's underlying CTCL can be challenging and can lead to treatment interruptions or even premature drug discontinuation. We performed a thorough clinical and histopathologic retrospective characterization of BVAR from a single institution. Utilizing polymerase chain reaction (PCR) and T-cell receptor high-throughput sequencing (TCR-HTS), we were able to isolate skin biopsy specimens from rash clinically suggestive of BVAR that also lacked a dominant TCR clone. A retrospective evaluation was performed of 26 biopsy specimens from 14 patients. Clinical features of BVAR included predominantly morbilliform or maculopapular morphology, delayed onset, and the trend toward moderate to severe classification, often requiring oral steroids. Most histopathologic specimens (25/26) showed spongiotic dermatitis as the primary reaction pattern. Many cases showed subtle findings to support a background interface or lichenoid eruption. Langerhans cell microabscesses were seen in one-fourth of specimens, and eosinophils were present in over one-half of the specimens. There were focal features mimicking CTCL, but these were not prominent. In 17 specimens with immunohistochemistry, the CD4:CD8 ratio in intraepidermal lymphocytes was relatively normal (1-6:1) in 65% (11/17) and 1:1 in 35% (6/17), demonstrating a trend toward increased CD8-positive cells compared with baseline CTCL. We have identified features that can help distinguish BVAR from a patient's CTCL, which can, in turn, help guide appropriate clinical management.

中文翻译：

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Brentuximab Vedotin 相关皮疹的组织病理学和临床特征。


皮疹是 brentuximab vedotin (BV) 常见的不良事件之一，BV 是一种用于治疗皮肤 T 细胞淋巴瘤 (CTCL) 的 CD30 靶向抗体药物缀合物。然而，BV 相关皮疹 (BVAR) 的临床和组织病理学特征有限。将 BVAR 与患者的潜在 CTCL 区分开来可能具有挑战性，并且可能导致治疗中断甚至过早停药。我们对单一机构的 BVAR 进行了全面的临床和组织病理学回顾性表征。利用聚合酶链反应 (PCR) 和 T 细胞受体高通量测序 (TCR-HTS)，我们能够从临床提示 BVAR 的皮疹中分离出皮肤活检标本，该皮疹也缺乏显性 TCR 克隆。对 14 名患者的 26 份活检标本进行了回顾性评估。 BVAR 的临床特征包括主要为麻疹状或斑丘疹形态、起病延迟以及中度至重度分类的趋势，通常需要口服类固醇。大多数组织病理学标本（25/26）显示海绵状皮炎是主要反应模式。许多病例显示出微妙的发现来支持背景界面或苔藓样喷发。四分之一的标本中可见朗格汉斯细胞微脓肿，超过一半的标本中存在嗜酸性粒细胞。有一些类似于 CTCL 的局灶性特征，但这些特征并不突出。在 17 例免疫组化标本中，表皮内淋巴细胞 CD4:CD8 比例相对正常 (1-6:1)，占 65% (11/17)，占 35% (6/17) 为 1:1，显示出增加的趋势CD8 阳性细胞与基线 CTCL 相比。 我们已经确定了有助于区分 BVAR 与患者 CTCL 的特征，从而有助于指导适当的临床管理。