Clinicopathologic analysis of renal angiomyolipoma / 中华泌尿外科杂志

ABSTRACT

Objective To investigate the clinicopathologic characteristics,diagnosis and differential diagnosis,and the neoplastic nature of renal angiomyolipoma(RAML).Methods A retrospective study was done by reviewing the clinical information of 62 cases(20 men and 42 women;age range,24-73 years; mean age,46 years)of RAML.HE and immunohistochemical staining were performed on paraffin-embedded tissues with a panel of antibodies including HMB45,Melan-A/MART-1,smooth muscle actin(SMA),Ki-67 and P53.Results Of the 62 cases,42 presented with clinical symptoms,and 6 had concomitantly tuber- ous sclerosis.Most of the tumors were sharply demarcated from the surrounding kidney parenchyma.Histolog- ically,the tumors were composed of 3 components in different proportionsabnormal blood vessels,variously differentiated smooth muscle cells and adipose tissues.No vascular infiltration was observed.In these cases, mixed type was in 38 cases(61.3%) ,myomatous type in 14(22.6%),lipomatous type in 10(16.1%) according to classification criteria.Immunohistochemically,the tumor cells were positive for HMB45,Melan- A/MART-1 and SMA.The expression of Ki-67 protein was negative in most eases,and that of P53 was nega- tive in all.Follow-up lasted 1-7 years,and all the cases were alive with no evidence of recurrence and me- tastasis.Conclusions RAML is mostly of mixed type.No vascular infiltration is one of its histologic fea- tures,Immunohistochemically,RAML is characterized by positive expression of HMB45,Melan-A/MART-1 and SMA.The low or negative expression of Ki-67 and P53 protein indirectly support that RAML is a benign tumor.