Grading scheme for transitional cell carcinoma. Grade 1Ñusu. pedunculated, soft pink, delicate, frond-like papillary structures with central fibrovascular core, transitional cells almost identical to normal, with few mitoses; grade 2Ñmore solid consistency than grade 1, more crowding and layering of cells, with enlarged nuclei and scattered mitoses; grade 3Ñsessile, cauliflower-type form, frequent ulceration and necrosis, with common mitoses; grade 4Ñsessile, necrotic, ulcerated, widely invasive, pronounced cellular atypia and pleomorphism, with frequent mitoses.