皮肤颗粒细胞瘤(GCT)是罕见的肿瘤,通常表现出良性的临床行为,并且可能是雪旺氏细胞起源。由于浸润性生长模式,GCTs的一些组织学和免疫组织化学变异可能会带来挑战。神经周浸润,和Melan-A的表达在这个案例报告中,我们介绍了一名27岁的男性,他在几年前曾被诊断为背部典型的GCT。来自近端手掌的当前活检显示细胞学上相似的肿瘤,具有广泛的神经周围扩散和Melan-A的显着阳性。虽然不常见,这些特征与GCT的组织学表现一致.目前对GCT的组织发生的看法,临床关联,与黑色素瘤的鉴别诊断,并讨论了恶性GCTs的组织学标准。一组免疫组织化学染色,包括抑制素-α和黑色素瘤中优先表达的抗原(PRAME),建议用于罕见的Melan-A阳性GCTs。
Cutaneous granular cell tumors (GCTs) are rare tumors that typically exhibit benign clinical behavior and are likely of Schwann cell origin. Some histologic and immunohistochemical variants of GCTs may present challenges due to infiltrative growth patterns, perineural invasion, and expression of Melan-A. In this
case report, we present a 27-year-old male who had previously been diagnosed with a typical GCT on the back a few years ago. The current biopsy from the proximal palm demonstrated a cytologically similar tumor with extensive perineural spread and notable positivity for Melan-A. Although uncommon, these features are consistent with the histological appearances of GCTs. The current views on the histogenesis of GCTs, clinical associations, differential diagnosis with melanoma, and histological criteria for malignant GCTs are discussed. A panel of immunohistochemical stains, including Inhibin-α and preferentially expressed antigen in melanoma (PRAME), is proposed for use in rare instances of Melan-A-positive GCTs.