ALLELIC LOSSES AT CHROMOSOMES 1P, 2P, 6P, 10P, 13Q, 17P, AND 21Q SIGNIFICANTLY CORRELATE WITH THE CHROMOPHOBE SUBTYPE OF RENAL-CELL CARCINOMA

We analyzed 50 sporadic renal cell carcinomas (RCCs) for loss of heter ozygosity (LOH) at the chromosomal regions 1p, 2p, 6p, 7q, 10p, 11p, 1 3q, 14q, 17p, 21q, and 22q. Histologically, the tumors were distinguis hed into clear cell, chromophilic, and chromophobe carcinomas. Whereas LOH at 14q was identified in 42-64% of all three tumor types, only th e chromophobe tumors showed high frequencies of LOH (73-91%) at 1p, 2p , 6p, 10p, 13q, 17p, and 21q. These findings provide substantial evide nce that the chromophobe subtype of RCC represents a distinct genetic entity. Thus, specific LOH patterns may define the histogenesis and on cogenesis of chromophobe RCC and may be useful in tumor diagnosis and clinical prognosis.