Khan Jawad, Kashif Amna, Safdar Fatima, Rashdi Pir Sameeullah Shah, Rehmat Sadaqat Ullah, Shehzad Hira
Department of Urology, Ayub Teaching Hospital, Abbottabad, PAK.
Department of Surgery, Jinnah Sindh Medical University, Karachi, PAK.
Cureus. 2025 Aug 6;17(8):e89512. doi: 10.7759/cureus.89512. eCollection 2025 Aug.
This report presents the case of a 62-year-old male who presented with a two-month history of right flank pain and decreased appetite. Clinical evaluation revealed a palpable, non-tender mass in the right flank, while laboratory tests demonstrated mild anemia (hemoglobin 9.3 g/dL) with otherwise normal renal function. Contrast-enhanced computed tomography of the abdomen showed a large, heterogeneous mass arising from the lower pole of the right kidney, containing mixed densities, fatty components, and coarse calcifications. The initial differential diagnosis included angiomyolipoma. Following multidisciplinary discussion, the patient underwent radical nephrectomy. Gross examination revealed a lobulated, yellowish tumor with areas of necrosis and hemorrhage. Histopathological analysis confirmed the diagnosis of dedifferentiated liposarcoma, characterized by spindle cell proliferation with moderate nuclear atypia and mature adipocytes. Immunohistochemistry showed strong nuclear positivity for MDM2 and p16, supporting the diagnosis. The tumor was staged as pT3aNxM0. Postoperative follow-up was arranged to monitor for recurrence. This case highlights the diagnostic challenge posed by rare renal tumors with fatty components and emphasizes the importance of including dedifferentiated liposarcoma in the differential diagnosis. Early surgical intervention remains essential to optimize outcomes, given the tumor's limited response to adjuvant therapies.
本报告介绍了一名62岁男性患者的病例，该患者有两个月的右侧胁腹疼痛和食欲减退病史。临床评估发现右侧胁腹有一个可触及的、无压痛的肿块，而实验室检查显示轻度贫血（血红蛋白9.3 g/dL），肾功能其他指标正常。腹部增强计算机断层扫描显示右肾下极有一个大的、不均匀的肿块，包含混合密度、脂肪成分和粗大钙化。初步鉴别诊断包括血管平滑肌脂肪瘤。经过多学科讨论，患者接受了根治性肾切除术。大体检查显示为分叶状、淡黄色肿瘤，伴有坏死和出血区域。组织病理学分析确诊为去分化脂肪肉瘤，其特征为梭形细胞增殖，核中度异型，伴有成熟脂肪细胞。免疫组织化学显示MDM2和p16核强阳性，支持诊断。肿瘤分期为pT3aNxM0。安排了术后随访以监测复发情况。该病例突出了具有脂肪成分的罕见肾肿瘤所带来的诊断挑战，并强调了在鉴别诊断中纳入去分化脂肪肉瘤的重要性。鉴于肿瘤对辅助治疗反应有限，早期手术干预对于优化治疗结果仍然至关重要。
