Zhang Jun, Wang Wen-Juan, Chen Li-Hong, Wang Ning, Wang Ming-Wen, Liu Hao, Pang Li-Juan, Jiang Han-Guo, Qi Yan
Department of Pathology, Zhanjiang Central Hospital, Guangdong Medical University, Guangdong, China.
Department of Pathology, Shihezi University School of Medicine & the First Affiliated Hospital to Shihezi University School of Medicine, Xinjiang, China.
Front Oncol. 2023 Aug 22;13:1207536. doi: 10.3389/fonc.2023.1207536. eCollection 2023.
Epithelioid angiomyolipoma (EAML) is a rare type of mesenchymal angiomyolipoma with potential malignancy in the kidney that can cause lymph node metastases, local recurrence, and distant metastases. Herein, we describe a case of EAML in the right kidney of a 51-year-old man who was admitted to the hospital with a right abdominal mass. Computed tomography revealed a heterogeneously enhanced mass with blurred margins, which was considered a malignant tumor. A radical nephrectomy was then performed. Two years later, the patient developed liver metastases from EAML and was administered sintilimab combined with bevacizumab. The patient survived after 6 months of follow-up. Histologically, the tumors showed clear boundaries and no obvious capsules. The tumor tissue mainly consisted of epithelioid tumor cells, thick-walled blood vessels, and a small amount of adipose tissue. Tumor cells with lipid vacuoles and acinar areas were large, round, polygonal, eosinophilic, or transparent in the cytoplasm. The enlarged and hyperchromatic nuclei were accompanied by distinct nucleoli and pathological mitosis. These histopathological findings resembled those of renal cell carcinoma, and immunohistochemical analysis was performed. The tumor cells were diffusely positive for HMB45, Melan-A, CK20, vimentin antibodies, and TFE3, suggesting that the tumor originated from perivascular epithelioid cells, excluding renal cell carcinoma. The Ki-67 index was 10%. These histopathological features were observed in liver mass puncture tissues. We also summarized 46 cases of EAML with distant metastasis and explored the clinicopathological features of EAML to improve the treatment of the disease. EAML is often ignored in the clinical setting, leading to metastasis and recurrence. Therefore, EAMLs require long-term follow-up, and timely detection of recurrent disease can improve the prognosis.
上皮样血管平滑肌脂肪瘤（EAML）是一种罕见的间叶性血管平滑肌脂肪瘤，发生于肾脏，具有潜在恶性，可导致淋巴结转移、局部复发和远处转移。在此，我们描述一例51岁男性右肾EAML病例，该患者因右侧腹部肿块入院。计算机断层扫描显示一个边缘模糊的不均匀强化肿块，考虑为恶性肿瘤。随后进行了根治性肾切除术。两年后，该患者出现EAML肝转移，并接受了信迪利单抗联合贝伐单抗治疗。随访6个月后患者存活。组织学上，肿瘤边界清晰，无明显包膜。肿瘤组织主要由上皮样肿瘤细胞、厚壁血管和少量脂肪组织组成。含有脂质空泡和腺泡区域的肿瘤细胞大，呈圆形、多边形，胞质嗜酸性或透明。细胞核增大、染色质增多，伴有明显核仁和病理性核分裂。这些组织病理学表现类似于肾细胞癌，因此进行了免疫组化分析。肿瘤细胞对HMB45、Melan - A、CK20、波形蛋白抗体和TFE3呈弥漫性阳性，提示肿瘤起源于血管周上皮样细胞，排除肾细胞癌。Ki - 67指数为10%。在肝脏肿块穿刺组织中也观察到了这些组织病理学特征。我们还总结了46例发生远处转移的EAML病例，并探讨了EAML的临床病理特征，以改善该疾病的治疗。EAML在临床中常被忽视，导致转移和复发。因此，EAML需要长期随访，及时发现复发性疾病可改善预后。
