An institutional experience evaluating hTERT immunostaining in 100 consecutive ThinPrep urine specimens

Area of Science:

• Uro-oncology
• Cytopathology
• Biomarker research

Background:

• Expression of human telomerase reverse transcriptase (hTERT) in urothelial cells is linked to increased urothelial carcinoma risk.
• Immunocytochemistry offers a potential method for detecting hTERT in urine cytology specimens.

Purpose of the Study:

• To evaluate the utility of anti-hTERT immunocytochemistry using the SCD-A7 antibody in ThinPrep processed urine cytology specimens.
• To assess the diagnostic performance and potential challenges of hTERT staining in identifying urothelial carcinoma.

Main Methods:

• 100 consecutive urine cytology specimens processed with ThinPrep were stained for hTERT using the SCD-A7 antibody.
• Staining optimization was performed, and results were correlated with cytology diagnoses, histologic follow-up, and patient demographics.

Main Results:

• 68% of 92 evaluable samples were positive for anti-hTERT staining.
• 97% of specimens with atypical urothelial cells (AUCs) or higher diagnoses showed positive staining.
• 62% of negative for high-grade urothelial carcinoma (NHGUC) cases were also positive for hTERT, and nonurothelial cell staining was frequent (84%).

Conclusions:

• Interpretation of anti-hTERT immunocytochemistry in ThinPrep urine cytology is challenging due to nonurothelial cell staining and cytomorphology obscuration.
• The clinical significance of numerous hTERT-positive but cytology-negative cases remains uncertain and requires further investigation.