Purpose: Several studies have documented high incidence of urinary lithiasis after jejunoileal by-pass. Roux-en-y gastric bypass surgery (RYGB) is currently the most common bariatric procedure. Because of its difficult for absorption, RYGB has a potential risk to increase the incidence of lithiasis. This study was conducted in order to test the hypothesis that RYGB increases the incidence urolithiasis after 50% of excessive weight loss. Materials and Methods: We performed a retrospective cohort study to evaluate 58 patients who underwent RYGB at the Obesity Service at Santa Casa de Misericordia de Sao Paulo, between 2000 and 2005, with minimum follow-up of 10 and maximum of 72 months, after the procedure. Results: Forty-five (77.6%) patients had ≥ 50% loss of weight excess. There was no difference between the frequency of urolithiasis before and after the procedure, and nephrolithiasis was observed after surgery in only one patient, however this had been detected before the procedure. Conclusion: In the period studied, RYGB does not seem to affect the incidence of urolithiasis after weight reduction. This may be due to its smaller malabsorptive component as compared with jejunoileal “by-pass”, thereby possibly not significantly influencing the oxalate metabolism.

OBJECTIVE: To assess the occurrence of upper urinary tract urothelial tumors (UUTT) in Brazil. MATERIALS AND METHODS: We performed a clinical and histopathologic study of 33 patients who were diagnosed with a malignant neoplasm in the renal pelvis or ureter in the period of 1994 to 2004, in a single institution. RESULTS: Among the patients with upper urinary tract carcinoma, 70% were males and 30% females, with mean age of 65 ± 16 years (ranging from 31 to 91 years). Nineteen patients presented renal pelvis tumor (58%), 9 ureteral tumor (27%) and 5 synchronic pelvic and ureteral tumors (15%). Renal pelvis tumors represented 2.8% of all the urothelial neoplasms, and 11.4% of all renal neoplasms treated in the same period. Ureteral tumors represented 1.6% of all the urothelial malignancies surgically managed in these 11 years. Tobacco smoking was the most common risk factor, and analgesic abuse was not reported by those patients. Most carcinomas were high-grade and muscle-invasive. Mean time to diagnosis was 7 months, being hematuria the most common symptom. CONCLUSIONS: A high association was also found between UUTT and bladder urothelial carcinoma. UUTT were mostly seen in men in their seventies and related to a high overall and cancer-related mortality rate. The overall disease-specific survival was 40%, much lower than found in most of the reported series.

OBJECTIVE: To assess the incidence of bladder carcinoma infiltrating the prostate and prostate adenocarcinoma in patients undergoing radical cystoprostatectomy due to bladder cancer, as well as to assess if the characteristics of the bladder neoplasia influence the prostatic involvement by this neoplasia. MATERIALS AND METHODS: We retrospectively assessed 60 male patients, who underwent radical cystoprostatectomy between July 1997 and December 2003. Mean age was 66.7 years (40 and 93 years). The product of radical cystoprostatectomies was checked for involvement of urethra and prostate parenchyma by the primary neoplasia, and for the presence of associated prostate adenocarcinoma. Bladder neoplasia characteristics, such as localization, size, multifocality, association with in situ carcinoma and histological grade, were studied in order to assess the possibility of using such characteristics as predictive factors of prostate infiltration by bladder urothelial carcinoma. RESULTS: We observed the presence of 20% of patients with bladder carcinoma infiltrating the prostatic urethra, 23.3% of patients with infiltration of the prostate parenchyma and 28.3% of patients with associate prostate adenocarcinoma, resulting in a total of 55% of patients with prostatic involvement (infiltrative bladder carcinoma and/or adenocarcinoma). We also observed a statistically significant correlation between tumor location in the trigone, the presence of in situ carcinoma and the histological grade of the bladder tumor with prostatic infiltration by the vesical neoplasia. CONCLUSION: The coexistence of prostatic neoplasia in patients operated for bladder neoplasia was frequent in our sample (55%). We observed that the prostatic infiltration by bladder tumors occurs more frequently with tumors located in the trigone, with associated in situ carcinoma and with high histological grade. There was no correlation between neoplastic infiltration of prostate and multifocality or size of the bladder tumor in the studied sample.