Spindle cell neoplasms encountered in dermatologic surgery: A review

Cutaneous spindle cell tumors share the common feature of appearing as spindle-shaped cells on light microscopy. Their pathogenesis, presentation, and prognosis are highly variable, and numerous techniques for workup and treatment have been reported. We performed an analysis of the available scientific literature in order to codify the clinical, immunohistochemical, and biologic features of these tumors and to provide insight into the most effective practices for their management, with a focus on Mohs micrographic surgery (MMS). In this article, the clinical and histopathological characteristics of dermatofibrosarcoma protuberans, atypical fibroxanthoma, malignant fibrous histiocytoma, spindle cell squamous cell carcinoma, superficial leiomyosarcoma, desmoplastic melanoma, cutaneous angiosarcoma, and myofibrosarcoma are described, and methods for diagnosis, workup, treatment, and surveillance are evaluated. Cutaneous spindle cell neoplasms are diverse in origin, presentation, and behavior. Immunostaining assists in differentiating among the various types. Further workup is sometimes indicated to characterize local invasion or assess for metastatic disease. Surgery is typically the first-line treatment, and MMS is associated with low recurrence rates and a tissue-sparing advantage for many tumors. Adjuvant treatments, including radiation therapy, molecular-targeted therapy, and conventional chemotherapy, are sometimes indicated, and close clinical surveillance is required after treatment.