GIANT PIGMENTED FIBROEPITHELIOMA OF PINKUS MIMICKING MALIGNANT MELANOMA: A DIAGNOSTIC PITFALL

Background: Fibroepithelioma of Pinkus (FeP) is an uncommon fibroepithelial tumor traditionally regarded as a variant of basal cell carcinoma. Pigmented and giant forms are rare and may clinically and dermoscopically mimic malignant melanoma, creating a significant diagnostic challenge.
Case Presentation: We report the case of a 45-year-old man presenting with a 5 cm, slow-growing, sessile, partially ulcerated pigmented tumor on the lower back. Dermoscopy revealed shiny white streaks and extensive structureless blackish pigmentation, raising strong suspicion of malignant melanoma. A complete excisional biopsy was performed. Histopathological examination demonstrated thin, anastomosing strands of basaloid cells forming a fenestrated network embedded in a loose fibrovascular stroma, consistent with giant fibroepithelioma of Pinkus. Surgical margins were free of tumor. No recurrence was observed after three years of follow-up.
Conclusion: Pigmented and giant variants of FeP can closely simulate melanoma both clinically and dermoscopically. Histopathological examination of a completely excised specimen remains the diagnostic gold standard. Awareness of this entity is essential to avoid misdiagnosis while ensuring appropriate excisional management of suspicious pigmented lesions.