Background:
Chromophobe renal cell carcinoma (rcc) is a distinctive subtype of rcc with a more favorable prognosis than clear cell rcc. we describe the pathologic features of 23 solitary cases and 2 cases with coexistent papillary rccs, 7 of which developed metastases.
Methods:
Cases were retrieved from the pathology files of our institutions. clinical follow-up was obtained from the medical records. dna analysis was performed on feulgen-stained slides using image analysis.
Results:
Twenty-five cases were identified. all cases had characteristic pathologic features, including diffuse cytoplasmic reactivity for hale's colloidal iron. dna ploidy analysis of ten cases revealed a diploid pattern in five, a hyperdiploid pattern in four, and a hypodiploid pattern in one. follow-up was available for 20 cases, and metastases developed in 7 (from 4 to 120 months after surgery). in 5 of these cases, the tumors were solitary and more than 8 cm in greatest dimension and metastases developed in the liver. in both cases with papillary rccs in the same kidney, metastases developed in the lung, although which tumor metastasized is unknown.
Conclusions:
Despite the overall favorable prognosis for chromophobe rcc, large tumors and those with coexistent papillary rccs may produce in metastases.