皮内痣伴结缔组织增生性结节一例

Desmoplastic nodule associated with intradermal nevus:a case report

患者男,28岁,因左侧胸部单发褐色肿物4年、多发小丘疹1年就诊。皮肤科检查:胸部左侧一1.2 cm×1.1 cm×1.0 cm褐色类圆形肿物,质韧,其右侧数个直径3~5 mm褐色丘疹,左侧腋下淋巴结未触及肿大。手术完整切除肿物后行组织病理检查:肿物和小丘疹内均可见真皮浅层痣细胞聚集成巢,考虑皮内痣;最大肿物内见一结缔组织增生性结节,其内痣细胞散在分布于纤维之间,并见痣巨细胞;结节中痣细胞体积较大,呈上皮样或梭形,细胞核呈类圆形或梭形,可见明显核仁,痣细胞分裂象少见。免疫组化:皮内痣和增生性结节内痣细胞S100均阳性;皮内痣真皮浅层痣细胞Melan-A、HMB45阳性,而增生性结节内Melan-A、HMB45阴性;皮内痣及增生性结节Ki-671%、CD34阳性,P16、P63均阴性。诊断:皮内痣伴结缔组织增生性结节。

A 28-year-old male patient presented with a 4-year history of a solitary brown mass,and a 1-year history of multiple small papules on the left chest.Skin examination showed a quasi-round brown firm mass measuring about 1.2 cm×1.1 cm×1.0 cm in size on the left chest,and several brown papules with diameters ranging from 3 to 5 mm on the right side of the mass;no enlarged lymph nodes were detected in the left axilla on palpation.The mass and papules were completely resected,and histopathological examination showed clustered nevus cells in the superficial dermis of the mass and small papules,and the diagnosis of intradermal nevus was considered.There was a desmoplastic nodule in the mass,nevus cells were scattered among the fibers in the nodule,and giant nevus cells were also observed;the nevus cells in the nodule were relatively larger,epithelioid or spindle-shaped with round or spindle-shaped nuclei,obvious nucleoli,and rare mitotic figures.Immunohistochemical study showed that the nevus cells in both the intradermal nevus and proliferative nodule were positive for S100;the nevus cells in the superficial dermis of the intradermal nevus were positive for Melan-A and HMB45,while the nevus cells in the proliferative nodule were negative for Melan-A and HMB45;both the intradermal nevus and proliferative nodule tissues showed a Ki-67 index of 1%,positive staining for CD34,but negative staining for P16 and P63.Finally,the patient was diagnosed with intradermal nevus associated with desmoplastic nodule.