We report two cases of grade I papillary transitional cell carcinoma w
hich have a distinct pathological. The tumor was infiltrating the lami
na propria in the first case (pT1) and the superficial muscle in the s
econd case (pT2). These tumors were composed by nests and tubules with
few cytological atypias, making the diagnosis of cancer difficult. Th
e pronosis of these tumors is not well defined.