Examples of hTERT staining. a A cluster of 3 cells (top center) stains positive; note the negative cell on the right side of the field. The corresponding diagnostic specimen was called “negative for urothelial atypia or malignancy”; the patient was subsequently found to have a low-grade urothelial neoplasm. b A cluster of atypical urothelial cells, the majority of which stain positive. The corresponding diagnostic specimen was called “atypical urothelial cells of uncertain significance”; the patient was subsequently found to have high-grade urothelial carcinoma. c–h Additional specimens in which hTERT was interpreted to be positive. i An example of a specimen containing high-grade urothelial carcinoma cells in which hTERT was negative.