URINARY CYTOLOGY AND COMPETITIVE REVERSE-TRANSCRIPTASE POLYMERASE-CHAIN-REACTION ANALYSIS OF A SPECIFIC CD44 VARIANT TO DETECT AND MONITOR BLADDER-CANCER

Purpose: Recently a novel molecular approach, CD44 variant exon (v)8-1 0/CD44 v10 competitive reverse transcription-polymerase chain reaction (RT-PCR), was developed. CD44 competitive RT-PCR can detect a sparse population of cancer cells over expressing CD44 v8-10 among a much lar ger population of nonneoplastic cells in body fluids, that is pleural effusion and urine, by the measurement of transcriptional CD44 v8-10 r elative to CD44 v10. The use of the CD44 competitive RT-PCR assay to d iagnose and monitor bladder cancer was compared to urinary cytology. M aterials and Methods: Spontaneously voided wine samples from 71 patien ts with bladder cancer and 50 with benign urological diseases were ana lyzed by CD44 competitive RT-PCR and convectional urinary cytology. Ur ine samples from 24 patients with completely resected bladder tumors a lso were analyzed. Results: The CD44 competitive RT-PCR assay and urin ary cytology revealed a sensitivity of 77 and 58%, and a specificity o f 100 and 98%, respectively. Furthermore, combining the results of the 2 methods increased sensitivity to 90%. Urine samples from patients w ith bladder cancer following curative surgery were correctly diagnosed in 96% with the CD44 competitive RT-PCR assay compared to 83% with ur inary cytology, Conclusions: The CD44 competitive RT-PCR assay is a us eful, noninvasive method to diagnose and monitor bladder cancer. The a ssay could be an important adjunct to urinary cytology to detect exfol iated bladder cancer cells in urine.