الفهرس 
EPIDEMIOLOGY OF BLADDER CANCEROnly 14 pages are availabe for public view
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Abstract
Bladder cancer is the most common cancer in developed countries especially Egypt. It is characterized by high recurrence rate and most of the recurred cases may progress to a higher grade and stage. Therefore, long term and close surveillance of patients with bladder cancer is mandatory.
Cystoscopy and cytology are considered the gold standards procedures to detect or follow the course of bladder cancer. However, both techniques have low sensitivity. Furthermore, cystoscopy is an invasive procedure that may also cause urinary tract infection. Therefore, several urine-based ancillary tools have been developed. Among these is the fluorescent in situ hybridization method of examination of urinary cells for aberrations of chromosomes 3,7,9 and 17 known as Urovysion.
Our study aimed for comparing Urovysion with urine cytology for detection of bladder cancer and assessment of its relevance to both stages and histopathological grades of the tumor.
This study included 30 bladder cancer patients and 15 diseased control patients. Bladder cancer patients were classified according to stages into Tis, T1 to T4 and according to grade into G1 to G3. All patients were subjected to complete urine analysis, routine radiological investigations, urine cytology and Urovysion assay.
The results of the present study revealed that Urovysion had a much higher sensitivity 90% than urine cytology 46.6% for detection of bladder cancer. Combined use of urovysion and urine cytology increased the diagnostic sensitivity for early detection of bladder cancer from 90% to 96.7%. As regards urovysion assay specificity, only one case out of 15 diseased controls gave false positive results while no false positive results were detected by urine cytology.
The detection rate of positive results by urovysion increases with progression of tumor stages being 80% in Tis, 83.3% in stage T1, 100% in each of stage T2, stage T3 and T4. While for urine cytology, the detection rate was not associated with progression of tumor stages being 60% in Tis, 57.1% in stage T1, 50% in stage T2, 42.2% in stage T3 and 33.3% in stage T4.
There was positive association of increased frequency of positive results obtained only by urovysion assay on one hand and tumor grades on the other hand being for G1 40%; G2 100%; and G3 100% respectively.
When individual chromosomes were evaluated, it was found that chromosomes 7 and 17 were the most frequent chromosomes to be positive (56.7%) while chromosomes 3 and 9 were (36.7%, 46.7%), respectively. As regards tumor stages no significant association was found but chromosome 9 was the most frequently positive among other chromosomes in stages Tis and T1 and this goes with the hypothesis that chromosome 9 aberration is the earliest to occur in bladder cancer genesis. On the other hand, chromosomes 7 and 17 were the only that showed significant association with tumor grades.
In conclusion, urovysion; both by itself and in combination with urine cytology; offers a sensitive, reliable and non invasive approach to bladder cancer diagnosis. Urovysion is associated with invasiveness of bladder cancer from stage Tis, T1 to T4 and from grades G1 to G3. Thus, urovysion assay can be used as an important diagnostic and prognostic indicator of this disease.