Clinico-pathological analysis of 120 cases of renal angiomyolipoma with emphasis on follow-up

Objective To highlight clinical pathological features of renal angiomyolipoma(AML)and their prognostic significance by follow-up.Methods 120 AMLs between 1981-2010 were retrospectively analyzed and classified into three subtypes:classical,epithelioid with atypia,and epithelioid without atypia.χ2 test was performed to clarify significance of the specially pathological findings among the classical and epithelioid subtypes with or without atypia.Results All 120 AMLs were classified into classical and epithelioid with or without atypia.The classical AMLs were 78.3%(94/120),epithelioid AMLs(EAMLs)were 21.7%(26/120),of which 10 were with atypia(8.4%,10/120).EAMLs had more obvious mitosis,hemorrhage,and multinucleated giant cells than classical ones(P0.05).EAMLs with atypia had more nucleoli and mitosis than EAML without atypia(P0.05).Follow-up results of 86.7%(104/120)cases were obtained,and only one(0.8%,1/120)presented liver metastasis one year after nephrectomy.Conclusion Few AMLs and EAMLs are malignant.EAMLs with atypical nuclear features including nucleoli and atypical mitosis may possess malignant behavior.