A 73-Year-Old Female Diagnosed With Dermatofibrosarcoma Protuberans in the Primary Care Setting: A Case Report and Literature Review of Misdiagnosed Cases.

Dermatofibrosarcoma protuberans (DFSP) is a rare, slow-growing, malignant tumor in the dermis and subcutaneous fat diagnosed by pathological and immunohistochemical examinations. This case report provides the dermatological findings of a 73-year-old woman with DFSP who presented to a primary care clinic with a longstanding nodular lesion on her left upper thigh. Dermatological examination showed a solitary, skin-colored violaceous/hyperpigmented nodule on the superior anteromedial portion of the left thigh. A punch biopsy revealed spindle cell proliferation, and diffuse CD34 positivity, confirming the diagnosis of DFSP. A dermatology referral was placed for further management and complete surgical excision. Patient underwent wide local excision (WLE) and has no recurrence to date. Unfortunately, DFSP is commonly misdiagnosed before skin biopsy which delays treatment. This case is significant because DFSP is not often diagnosed accurately outside the dermatology specialty and serves as a reminder to practitioners to use biopsies during the diagnostic process of skin findings to prevent the delay in management.