DNA ploidy in carcinoma of the gallbladder. Prognostic significance and comparison of flow and image cytometry on archival tumor material.

The aim of this investigation was to determine whether the cytometrically assessed DNA ploidy is a parameter of prognostic significance in gallbladder carcinomas. For this purpose the DNA content of tumor cells from archival tumor material from 80 patients with cholecystic cancer was analysed retrospectively by using comparatively different cytometrical methods, namely flow cytometry (FCM) and image cytometry, using tissue sections (ICM-S) and nuclear suspensions (ICM-N). Conventional tumor classifications (according to pTNM and Nevin) were able to predict the further clinical course. DNA ploidy showed a statistically significant correlation only to histological grade (P < 0.001), but not to tumor stage and survival. Only a trend towards a poorer outcome for patients harboring non-diploid tumors became evident especially when no residual tumor was present postoperatively (R 0-stage; P = 0.08). The different cytometrical methods discussed in detail, showed a highly significant concordance in the determination of DNA index values (DI) and in the classification of the tumors as either diploid or non-diploid. In conclusion, our results indicate that cytometrical determination of DNA ploidy provides no further prognostic informations in gallbladder carcinomas as compared to conventional tumor staging.