Clinical Characteristics and Surgical Outcomes of Renal Epithelioid Angiomyolipoma: A Comparison with the Classic Type

Nattaporn Wanvimolkul; Ekkarin Chotikawanich; Siros Jitpraphai; Varat Woranisarakul; Thitipat Hansomwong; Kantima Jongjitaree; Pongsatorn Laksanabunsong; Ngoentra Tantranont; Tawatchai Taweemonkongsap

doi:10.33192/smj.v78i3.279923

Authors

Nattaporn Wanvimolkul Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Ekkarin Chotikawanich Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Siros Jitpraphai Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Varat Woranisarakul Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Thitipat Hansomwong Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Kantima Jongjitaree Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Pongsatorn Laksanabunsong Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Ngoentra Tantranont Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Tawatchai Taweemonkongsap Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.

DOI:

https://doi.org/10.33192/smj.v78i3.279923

Keywords:

Angiomyolipoma, Epithelioid, Renal, Surgery, Classic

Abstract

Objective: To compare clinical characteristics and surgical outcomes between patients with epithelioid angiomyolipoma (EAML) and classic angiomyolipoma (AML), and to identify factors associated with EAML diagnosis.

Materials and Methods: All patients with renal AML who underwent surgery at Siriraj Hospital between January 2013 and December 2024 were reviewed. Clinical features and surgical outcomes were compared between patients with classic AML and those with EAML, and predictors of EAML were evaluated using multivariable analyses.

Results: Among 116 eligible patients, 101 had classic AML and 15 had EAML (12.9%). Most patients were female and were diagnosed in their fifth decade. Demographics, tumor laterality, prevalence of tuberous sclerosis complex gene mutation, and comorbidities did not differ between the 2 groups. Palpable mass (26.7%) and hematuria (13.3%) were more frequent in patients with EAML than in those with classic AML. Most patients with EAML underwent radical or partial nephrectomy due to suspected malignancy. In multivariable analysis, tumor size ≥ 10 cm (odds ratio 15.44; P = 0.003) and a radiologic impression of cancer (odds ratio 46.98; P < 0.001) independently predicted EAML. Four patients with EAML had adverse pathologic features and experienced poor survival; 3 patients died with metastases. The 3-year overall survival was 100% in classic AML and 76.9% in EAML (P < 0.001).

Conclusions: Patients with EAML had less favorable surgical outcomes than those with classic AML. Larger tumor size and a preoperative radiologic impression of malignancy were associated with an EAML diagnosis. Adverse pathologic features in EAML suggest malignant potential.

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