Correlation of Transabdominal Ultrasonography and Cystoscopy in Follow-up of Patients with Non-muscle Invasive Bladder Cancer

Abstract

Cystoscopy (CS) is considered to be the gold standard in the follow-up of non-muscle invasive bladder cancer. However, CS is invasive, time-consuming, and expensive. On the other hand, modern sensitive transducers have improved the imaging of urinary tract rendering transabdominal ultrasonography (US) more effective in visualizing intraluminal filling defects in the bladder than it was in the past. Twenty-five follow-up patients of low-risk bladder cancer meeting the inclusion and exclusion criteria were included in study. Ultrasonography of the bladder was performed by a single senior radiologist, and subsequently, these patients were subjected to flexible cystoscopy under local anesthesia. Pain score was calculated for each of the cystoscopies done. Findings of transabdominal ultrasound of the bladder were correlated and compared with those of cystoscopy. Subjects with US and/or CS findings suggestive of recurrence underwent transurethral resection of bladder tumor (TURBT) under general anesthesia and confirmation of the bladder carcinoma was achieved by the histopathological examination. Mean patient age was 60.56 years with range of 29 to 77 years. The sensitivity of modern ultrasonographic techniques was found to be 84.61% with specificity of 91.7% taking flexible cystoscopy as the gold standard for detection of recurrence. The accuracy of US was 88% with positive predictive value of 91.7% and negative predictive value of 84.61%. Technological evolution has improved the accuracy of ultrasonography in diagnosis of bladder carcinoma. It represents a valuable surveillance tool in selected sub group of low risk non-muscle invasive bladder cancer patients.