Pilomatricoma of the calf: a case report and review of literature.

Introduction and importance: Pilomatricoma (PMC) is a benign adnexal dermal or subcutaneous tumor, which is derived from immature hair matrix cells. It makes up around 20% of all tumors related to hair follicles in most series and is therefore the most common hair-follicle neoplasm. Nevertheless, diagnosing it remains intricate due to the prevalence of more frequent pathological conditions in soft-tissue. Anatomopathological examination proves to be a valuable asset, offering a definitive and certain diagnosis. Case presentation: The authors hereby present a case of a 17-year-old patient with no medical history, who was referred to our medical unit subsequent to the emergence of swelling in the right calf. MRI results highlighted the presence of a subcutaneous nodule situated on the right calf. Following a percutaneous biopsy, the diagnosis of PMC was definitively confirmed. A successful surgical excision of the tumor was performed, and the postoperative progress demonstrated positive outcomes. Clinical discussion: PMC usually appears as flesh-colored to white, firm papules or papulonodules that may have an overlying pink to blue hue. MRI plays a crucial role in diagnosis, as it delineates the tumor's extent in relation to the skin and muscle compartments. Preoperative histological confirmation is essential to rule out other potential diagnoses and precisely establish the required resection margins. Conclusion: PMC is an infrequent occurrence in general surgery departments. General surgeons should, however, be well-acquainted with this benign tumor while assessing soft-tissue masses.