The use of urine cytology for diagnosing bladder cancer in spinal cord injured patients

Abstract

Purpose: The diagnosis of bladder cancer in spinal cord injured patients is complicated by inflammatory changes caused by long-term indwelling catheters, which make cystoscopic followup difficult. We evaluated cytology as an aid in diagnosing bladder cancer in spinal cord injured patients.

Materials and methods: The charts of 208 spinal cord injured patients were reviewed retrospectively from January 1988 to July 1995 to define the value of cytology in the diagnosis of bladder cancer in this population. In all patients at least 1 urine cytology study was done less than 3 months before bladder biopsy. We examined 272 bladder biopsies (several patients underwent more than 1 biopsy at least 1 year apart) with 1 to 6 cytology studies done before biopsy.

Results: Cytology results were classified as negative-no malignant cells, inflammation or benign urothelial cells, reactive-atypia or atypical reactive and suspicious-atypical suspicious, keratinizing squamous metaplasia, suspicious for cancer, cancer or dysplastic. A total of 960 cytology specimens was obtained before the 272 biopsies (average 3 before each biopsy). Of 17 patients with cancer 12 had at least 1 prior suspicious urine cytology result. The sensitivity and specificity of cytology were 71 and 97%, respectively, when evaluating only patients with suspicious findings.

Conclusions: The high sensitivity and specificity of multiple cytology studies in this population suggest that cytology is a useful adjunct to improve the detection of bladder cancer in spinal cord injured patients with chronic (longer than 5 years) indwelling catheters. We recommend a minimum of yearly cytology in all high risk spinal cord injured patients with subsequent biopsies in all patients with any suspicious finding.