Pleomorphic lipoma of the loin region; a case report with literature review

Abstract

Introduction: Pleomorphic lipoma (PL) is a rare type of lipoma that accounts for only 1.5% of all adipocytic tumors. The aim of this report is to present the first case of PL in the flank. Case report: A 67-year-old male presented with fullness of the right flank, without any other symptoms. On examination there was a soft mass that mimicked hernia. Laboratory findings showed elevated renal function tests (blood urea of 46.1 mg/dl and s. creatinine of 1.59 mg/dl) Computed tomography (CT) scan showed a large fatty mass lesion (25 × 18 cm) in the right lower abdomen under the right-side external oblique muscle and over the internal oblique muscle with no extension to the abdomen, imaging features were suggestive of lipoma. The patient was operated for transverse flank incision to completely remove the mass, which was yellow in color. Histopathology confirmed the diagnosis PL. The operation was uneventful. Discussion: PL is characterized by the admixture of variable sized adipocytes and pleomorphic multinucleated giant cells with floret-like arrangement. It is a disease of old ages with higher male predominance, and mostly occurs in the subcutaneous tissue of the posterior neck, upper back and shoulders. PL localization in deep tissues is highly rare with a very few cases being reported in the intramuscular region. Conclusion: PL in the flank is an exceptional finding with the current case being the first report in the literature. Histopathology is the only key to provide definitive diagnosis. Highlights

An extremely rare neoplasm ‘atypical spindle cell pleomorphic lipomatous tumor’: a case report

“…They are termed as a collection of proliferating matured fat cells, encapsulated by a thin fibrous tissue. Lipomas are generally benign tumors [ 1 ]. Spindle cell lipoma differs from liposarcoma because it does not contain lipoblasts and lacks MDM2 and CDK4 amplification [ 2 , 3 ].…”