Abstract：
Lymphomatoid papulosis (LyP) has several histopathologic presentations. LyP featuring gamma-delta (γδ) T-cell receptor expression may masquerade as and may be misdiagnosed as aggressive cutaneous T-cell lymphoma, particularly primary cutaneous γδ T-cell lymphoma (PCGDTL) or γδ mycosis fungoides. We performed a clinicopathologic analysis of the largest series of LyP featuring γδ T-cell expression. We identified 26 patients with a diagnosis of LyP with γδ T cells from our institutions, as well as through a comprehensive review of the literature, and characterized these cases. Most cases were treated with topical steroids or not treated at all. The majority of cases showed a CD4 - CD8 + phenotype and featured at least one cytotoxic marker. Histopathologic features included an intraepidermal or dermal infiltrate with large cells and frequent angiotropism. One case was initially misdiagnosed as PCGDTL, requiring further therapy. Our case series, the largest international cohort of γδ T cell predominant LyP cases, confirms marked clinicopathologic heterogeneity that may contribute to misdiagnosis, reasserting the need to identify classic clinical features, CD30 + T-cell components, and markers of cytotoxicity when dealing with this differential diagnosis. A limitation of this study includes somewhat limited follow-up, histologic, and immunophenotypic information for some cases.
摘要：
淋巴瘤样丘疹病（LyP）有几种组织病理学表现。以γδ（γδ）T细胞受体表达为特征的LyP可能伪装成侵袭性皮肤T细胞淋巴瘤，特别是原发性皮肤γδT细胞淋巴瘤（PCGDTL）或γδ真菌病。我们对具有γδT细胞表达的最大系列LyP进行了临床病理分析。我们从我们的机构中确定了26例诊断为具有γδT细胞的LyP的患者，以及通过对文献的全面回顾，并描述了这些案件。大多数病例用局部类固醇治疗或根本不治疗。大多数病例表现为CD4-CD8表型，并具有至少一种细胞毒性标志物。组织病理学特征包括表皮内或真皮浸润，大细胞和频繁的血管生成。1例最初被误诊为PCGDTL,需要进一步的治疗。我们的案例系列，最大的国际γδT细胞优势LyP病例队列，证实了可能导致误诊的明显临床病理异质性，重申需要确定经典的临床特征，CD30+T细胞成分，以及处理这种鉴别诊断时的细胞毒性标志物。这项研究的局限性包括一些有限的随访，组织学，和一些病例的免疫表型信息。
