J Drugs Dermatol. 2020 Feb 1;19(2):205-206. doi: 10.36849/JDD.2020.4640.
Here we report a case of linear porokeratosis with recurrent malignant degeneration to squamous cell carcinoma (SCC) recurring six years after excision of initial SCC. A 79-year-old woman presented with a friable tumor located within a longstanding lesion on her posterior thigh. Six years prior, she was diagnosed with SCC arising within the same lesion, which had been surgically excised with negative margins. Physical examination revealed a 3.5 x 2.7 cm friable tumor on the left proximal posterior thigh. The tumor was located within a hyperpigmented and erythematous scaly linear plaque within a line of Blaschko, extending from the left buttock to the left distal posterior thigh. Two 4 mm punch biopsies were performed: one of the erythematous plaque on the left buttock and one from the friable tumor on the left posteromedial thigh. Histology from the left buttock revealed a cornoid lamella consistent with porokeratosis and the left posteromedial thigh revealed SCC. The patient underwent Mohs micrographic surgery with negative margins, followed by a linear repair. Porokeratosis is a disorder of epidermal keratinization that has been associated with malignant degeneration, although such cases are rare. The risk of recurrence of SCC arising within a porokeratosis is unknown. This case emphasizes the importance of ongoing monitoring for malignant degeneration within these lesions. J Drugs Dermatol. 2020;19(2)205-206. doi:10.36849/JDD.2020.4640
我们在此报告一例线性角化病，其鳞状细胞癌（SCC）在最初 SCC 切除后六年复发且恶性转化。一名 79 岁女性因位于大腿后侧长期病变内的易碎肿瘤就诊。六年前，她被诊断为 SCC，起源于同一病变，该病变已通过手术切除且切缘阴性。体格检查显示左大腿近端后外侧有一个 3.5 x 2.7 cm 的易碎肿瘤。该肿瘤位于 Blaschko 线上的色素沉着和红斑鳞屑性线状斑块内，从左臀部延伸至左大腿后远端。进行了两次 4mm 打孔活检：一次取自左臀部的红斑斑块，一次取自左大腿后内侧易碎肿瘤。左臀部的组织学显示角蛋白板层一致，符合角化病，而左大腿后内侧则显示 SCC。患者接受了 Mohs 显微镜手术，切缘阴性，随后进行了线性修复。角化病是一种表皮角化的疾病，与恶性转化有关，尽管这种情况很少见。角化病内 SCC 复发的风险尚不清楚。该病例强调了对这些病变内恶性转化进行持续监测的重要性。J Drugs Dermatol. 2020;19(2)205-206. doi:10.36849/JDD.2020.4640
