The Clinical Characters And Risk Factors In Recurrence Of Non-muscle Invasive Bladder Cancer

Background: Bladder cancer is the most common malignant tumor, it shows an increasing trend of incidence in recent years and approximately 75% of patients with bladder cancer were male. There were two established risk factors for bladder cancer, one was smoking and the other one was history of exposure to certain carcinogens. About 80% bladder cancer confined to the bladder mucosa, known as non-muscle invasive bladder cancer (NMIBC); while the other 20% was muscle invasion bladder cancer. The two types of bladder cancer were completely different in treatment and prognosis: NMIBC was low grade but high risk of recurrence in the new bladder cancer patients after resection by transurethral resection of bladder tumor (TURBT), if further treatment was absent, the recurrence rate was about 70% and about 35% of patients would face with a increasing stage and grade. Recurrence of bladder cancer are closely related with many factors, analysis and study of these factors in bladder cancer recurrence plays an important role, particularly in further treatment, follow-up and long-term prognosis. To improve the efficacy of bladder cancer and reduce recurrence rate, a considerable number of researches has been done to find out the risk factors affecting the prognosis, however most of them were still controversial or lack of support with large-scale researches. A retrospective study of 407 cases with non-muscle invasive bladder cancer was done to analysis clinical data of patients including age, gender, tumor number and size and other factors which were affected with the recurrence of bladder cancer, we hoped this study would provide a basis for clinical practice.Objective: To investigate the recurrence-related factors of non-muscle invasive bladder cancer and its clinical characteristics, and analysis the role of various risk factors in prognosis and outcome, meanwhile to give interventions and countermeasures.Methods: A retrospective study was done to analysis 407 cases that were diagnosed with non-muscle invasive bladder cancer in urology department, the First Affiliated Hospital of Soochow University from January, 2004 to January, 2011. All clinical information were collected, including: gender, age, chief complaint, past treatment and recurrence of bladder cancer, smoking history, imaging data, surgical type, tumor number, size, pathology, tumor grade, bladder instillation, time, dose, recurrence and progress. Follow-up data were collected in outpatient department or by telephone. Univariate and COX multivariate analysis were done for screening the significant indicators that affect the recurrence of bladder cancer risk factors and patient survival curves was draw. Analysis the clinical characters of T1 high grade (T₁G₃) bladder cancer and compare the outcomes of different treatment method.Results: Univariate analysis showed that gender (P=0.018), tumor stage (P=0.021), grade (P=0.048), tumor number (P=0.002), previous recurrence (P=0.001) and intravesical instillation treatment (P=0.004) were associated with tumor recurrence; age, tumor location, tumor size, previous recurrence times, and infusion drugs had no effect in tumor recurrence (P>0.05). Characters of T₁G₃ were significantly different with other types of bladder cancer including age (P=0.024), gender (P=0.013), tumor number (P=0.036), number of patients recurrence within one year (P=0.043), recurrence time (P=0.032) and progress time (P=0.039). T₁G₃ bladder cancer treated with intravenous chemotherapy had significantly longer recurrence time compared with intravesical instillation treatment (P=0.032).Conclusion: Gender, tumor stage and grade,previous recurrence, tumor number, and whether routine intravesical instillation treatment play the most important role in recurrence of non-muscle invasive bladder cancer. Combine with transurethral resection of bladder tumor and intravenous chemotherapy can significantly prolong recurrence time in high-risk T₁G₃ non-muscle invasive bladder cancer, and intravenous chemotherapy is well tolerated in patients.