Giant nonencapsulated pubic lipoma: a case report and literature review on differential diagnoses of atypical lipomas

Lipomas have been previously documented in the literature. Here, we present a rare case of a lipoma with exceptionally unusual size, localization, and structure. Due to exceptional presentation, we reviewed the literature for differential diagnoses. A 62-year-old female presented with a history of a slow-growing mass in the mons pubis over the past five years. The patient underwent open surgical excision. Postoperative pathological examination revealed a tumor measuring 210 × 150 × 90 mm and weighing 1,280 g; notably, no capsule formation was observed, and no evidence of malignancy was detected. During a three-year follow-up, no recurrence was observed. The rare localization and unusually large size of the lipoma may represent a component of a broader diagnostic spectrum, including liposarcoma, lipodystrophy, and rare adipose disorders (RADs). In unusual presentations of lipoma, preoperative MRI is recommended to assist in excluding malignancy, defining lesion margins, and assessing involvement of adjacent tissues, thereby minimizing unnecessary resection and improving surgical outcomes.