Little is known about the association of angiomyolipoma and adult renal-cel
l neoplasia. We studied the clinicopathologic features of 36 patients with
concurrent angiomyolipoma and renal-cell neoplasia from the consultation an
d surgical pathology files of nine institutions. HMB-45 immunoreactivity wa
s analyzed in both neoplasms. Twenty-five sporadic cases of patients with a
ngiomyolipoma and renal-cell neoplasia and II cases of patients with tubero
us sclerosis, as defined by Gomez' criteria, had mean ages of 59 and 53 yea
rs, respectively, and female-male ratios of 2:1 and 5:1, respectively. The
mean size of the angiomyolipomas was 1 cm in the sporadic cases and 3 cm in
those patients with tuberous sclerosis (medians: 0.5 and 3 cm, respectivel
y, P =.002). The mean sizes of the renal-cell neoplasms were 5 cm in sporad
ic cases and 6 cm in patients with tuberous sclerosis (medians: 4 and 5 cm,
respectively; P =.88), In both clinical settings, angiomyolipoma was more
commonly the incidental tumor. Clear-cell (conventional) renal-cell carcino
ma was the most common renal-cell neoplasm in both groups of patients, acco
unting for approximately two thirds of the tumors. In patients with tuberou
s sclerosis, 27% of renal-cell neoplasms were oncocytomas, compared with 8%
in sporadic cases (P =.15). Papillary neoplasia, chromophobe, and collecti
ng-duct renal-cell carcinoma were found only in sporadic cases. All of the
22 renal-cell neoplasms studied were negative for HMB-45, whereas all 25 an
giomyolipomas studied were positive.