Individual learning curve reduces the clinical value of urinary cytology.

UNLABELLED: The aim of the study was to define the learning curve of a single cytologist as a limitation of urinary cytology. A total of 1034 cytologic and histologic findings of patients undergoing transurethral resection of the bladder for suspicion of bladder cancer were reviewed, and cytologic evaluations of a single cytologist from the beginning of his learning period were compared with the results of a cytologist at a national reference center. Our results showed that the individual learning curve has a significant impact on the quality of urine cytology.

BACKGROUND: To define the learning curve of a single cytologist as a limitation of urinary cytology and to compare his results with a reference center for urinary cytology.

PATIENTS AND METHODS: Cytologic and histologic findings of patients undergoing transurethral resection of the bladder for suspicion of bladder cancer were reviewed. Cytologic evaluations from a single local cytologist during his learning period and of a cytologist of a national reference center were compared. Changes of sensitivity and specificity of cytology from the local cytologist over the time period were assessed. Differences were estimated by using kappa statistics.

RESULTS: The local cytologist evaluated 1034 cytologic findings. Sensitivity and specificity of cytology estimated by the local cytologist were 86% and 66% at the beginning of the learning period, but 68% and 84% at the end of it (P ≤ .05). In high-grade carcinomas, sensitivity did not decrease over the years (P > .05). In contrast, the sensitivity in the diagnosis of low-grade tumors decreased from 86% to 56% (P ≤ .05). The reference center estimated a constant sensitivity and specificity of 59% and 97%, respectively. Agreement of findings between local and national cytologists increased significantly over the learning period (P < .05).

CONCLUSION: The individual learning curve has a significant impact on the quality of urinary cytology. Both specificity of cytology and sensitivity for low-grade tumors changed significantly when done by a local cytologist at the beginning of learning period. These findings emphasize the impact of the individual learning curve on the clinical value of urinary cytology in diagnosis of bladder cancer.