Predictive value of DNA ploidy in bladder cancer treated with preoperative radiation therapy and cystectomy

DNA ploidy as a prognostic factor in muscle invasive transitional cell carcinoma of the bladder

Radical cystectomy represents the treatment of choice for muscle-infiltrative bladder carcinoma; however, about 50% of patients relapse and die from the disease. In the present study, the prognostic significance of the DNA ploidy in transitional cell carcinoma of the urinary bladder (TCCB) is analyzed. The study was carried out on 66 patients with TCCB who underwent radical cystectomy. DNA ploidy was determined by flow cytometry (FCM) on paraffin-embedded specimens, and the results were analyzed and correlated with the tumor malignancy grade and stage and the clinical course. Forty of the 66 tumors studied (63%) were aneuploid. Aneuploid status was correlated with higher tumor T stage (P < 0.001) and grade (P < 0.001). Median follow up was 68 months (range: 12-105). Median survival was significantly longer in patients with diploid tumors (> 60 vs 45 months, P < 0.001). All patients with diploid tumors were alive and free of bladder cancer during follow-up, in contrast to only 30% of patients with aneuploid tumors. DNA ploidy was an independent prognostic factor, as shown by multivariate analysis (P = 0.006). All patients with pT > or = 3b and diploid tumors were alive at the time of analysis as opposed to none with aneuploid tumors. The results of this study suggest that DNA ploidy can provide prognostic information on patients with muscle invasive carcinoma of the bladder and might represent a means of selection for postoperative management.

Radiotherapy in bladder cancer

In the present review, we have evaluated the outcome of radiotherapy in patients with bladder cancer. The exact value of radical radiotherapy is difficult to establish because changes in treatment techniques and selection of patients have biased the results. The 5-year survival rates are reported to be 35-71% in T1 tumors, 27-59% in T2 tumors, 10-38% in T3 tumors and 0-16% in T4 tumors. Several other factors, like performance status and hemoglobin level, are important for the outcome. Morbidity of radical radiotherapy depends on several treatment and patient related factors, but 50-75% experience acute intestinal or urological symptoms and 10-20% may develop severe late toxicity, depending on the kind of registration. The importance of field size or overall treatment time cannot be established from available data. Hyperfractionation with dose escalation has proven effective in one study. Preoperative radiotherapy with cystectomy has not proven better than cystectomy alone or better than radiotherapy alone. The addition of systemic chemotherapy has increased disease-free survival, but has not significantly reduced the rate of distant metastases or improved overall survival. Presently, the standard radiation regimen is a conventional dose and fractionation schedule to a total dose of 60-66 Gy with a three- or four-field technique covering the bladder and tumor. The efficacy of additional irradiation of regional lymph nodes is questionable. New treatment possibilities with advanced techniques of radiotherapy, hyperfractionation and dose escalation and/or the addition of systemic chemotherapy may improve outcome. These options should be further explored in clinical trials.