Retrospective Study Of DNA Flow Cytometry Values In Diagnosis And Prognosis In Bladder Tumor

Objective: To evaluate the sensitivity of DNA flow cytometry (FCM) for detection of DNA aberration in bladder tumor by investigating the relationship between diagnose and DNA heteroploid, S-phase fraction (SPF), coefficient of variation (CV) for the G0/G1 peak and apoptotic peak (APO), respectively; as well as the relevancy between tumor grade by pathology and the prognosis in urinary bladder tumor.Methods: The experiment includes three processes, such as, urine sample collection and preparation, DNA fluorescence staining, and detection/analysis by FCM.53 cases of bladder tumor (tumor group) and 26 cases of non-tumor (control group) were enrolled into this retrospective study. The diagnosis of bladder tumoris confirmed by the criterion by Collste and Klein. The cases of bladder tumor group included 4 sub-groups such as: papillary tumor of bladder, grade Ⅰ bladder cancer, grade Ⅱ bladder cancer, grade Ⅲ bladder cancer. Samples of the second morning urine were obtained from patients admitted in this study. Cells isolated from urine samples were analyzed by flow cytometry for DNA measurements such as: DNA heteroploid, SPF, CV, and APO. Each index was further compared between bladder tumor group and control group, as well as among the 4 bladder sub-groups.Results: The ratio of positive-FCM-cases in bladder tumor group was significantly higher than that in control (71.7% vs. 26.9%; X~2=12.23, V=1, p =0.000). The difference of ratio of DNA heteroploid between G3 and G1, G3 and papillary tumor, and G2 and G1 was significant (three all p<0.05), while that between G3 and G2, G2 and papillary tumor, and G1 and papillary tumor was not significant (three all p > 0.05).The ration of recrudesce of bladder tumor in DNA- heteroploid cases was significantly higher than that in non- DNA- heteroploid cases (87.5% Vs. 45.9%; X~2=7.94, V=1 ,p =0.005). The difference of ratio of SPF>15% between bladder tumor group and control is significant (58.5% Vs. 19.2%, X~2=10.84, V=1, P=0.001). Besides that, the difference of the value of SPF between every 2 grads in bladder tumor group was significant (all p<0.05), except G2 and G1 (p > 0.05), which showed that the higher grade of bladder tumor exhibited higher value of SPF. Furthermore, the value of SPF in 31 recrudesce-bladder tumor cases was significantly greater than that in 22 non- recrudesce-bladder tumor cases (24.66±7.45 vs.12.87±5.67; t=6.24,p=0.000). Additionally, the ratio of CV > 9% in bladder tumor cases is significantly higher than that of non-tumor (49.1% Vs. 15.38%, X~2=8.39, V=1,P=0.04). As to the ratio of APO, bladder tumor group revealed significantly bigger ration than control (32.1% vs. 11.5%; X~2=3.89, V=1, P < 0.05). Among positive and suspicious-positive FCM cases in control group, urinary infection cases occupied 58.3%, which implied that urinary infection might the main cause of false-positive in FCM.Conclusion: DNA FCM appears to be a clinically sensitive, convenient, and safe laboratory procedure to monitor patients with bladder tumor. Heteroploid is a specific characteristic of bladder tumor, which is also more likely to induce tumor recurrence. SPF>15% and CV>9% are both valuable factors of this assessment, and high SPF value is inclined to recurrence. In total, FCM is effective but limited in diagnosis and prognosis in urinary bladder tumor because of the false-positive and false-negative results. Therefore, FCM should be used combining clinical data in diagnosing urinary bladder tumor.