Der Lymphknotenstatus beim Prostatakarzinom - Korrelationen mit präoperativen Parametern und prognostischen Endpunkten unter besonderer Berücksichtigung der Lymphknotendichte

Globally, prostate cancer is the fourth most common male malignant neoplasm. In the male population of Western Europe and North America it claims the highest incidence and the second most common cause of lethality of all malignant tumors. In early stage disease, therapy of choice is radical prostatectomy including pelvic lymphadenectomy to detect metastatic spread to the lymph nodes. It is well acknowledged that the presence of lymph node metastasis is a poor prognostic sign. Up to now, it was distinguished between N0- and N1-status, this classification seems to be too simple for a differentiated consideration of prognosis. In recent years, great advances in diagnosis and treatment have been achieved, however, many questions remain. Amongst others, these questions concern the impact on prognosis of different characteristics of lymph node metastasis. The purpose of this study was, on the one hand, to determine the predictability of lymph node metastasis by the use of preoperative surveyed parameters and on the other hand, to show which single factors in positive lymph nodes affect prognostic endpoints. 913 patients from the Department of Urology, University Medical Center Marburg were analyzed retrospectively, 99 patients showed histologically proven lymph node metastasis (10,84%). Median follow-up was 51 months after radical prostatectomy. A data base with the SPSS software was established for the aquisition and statistical analysis of the patients parameters. The evidence for the ability of prediction of lymph node infiltration by the use of the pretherapeutic surveyed parameters clinical stage, PSA and Gleason-Score was clearly shown for each single factor and in multivariate analysis, too, with highly significant values (p<0,001). In a second part of this study, the correlation of the pN-status as well as the different specifications of lymph node metastasis like extranodal growth, lymph node density and absolute lymph node count on the one hand and the prognostic parameters survival, recurrence-free survival, recurrence-free interval and cancer-specific mortality on the other hand, was examined. Therefor, tables, statistical tests and Kaplan-Meier survival estimates were created. Overall survival was not dependent on the pN-status. In synopsis with comorbidities, tendencies were observable. The lymph node status correlated significantly with the frequency of disease recurrence (p=0,046). In the analyzed study cohort and with the given follow-up, time to progression was not correlating significantly with any of the examined parameters. Caused by the nature of slow progredience of prostate cancer, in this study, the follow-up was too short and the particular groups of patients were too small to achieve significant results concerning these questions. Only two out of the 913 patients died specifically by prostate cancer, both of them had positive lymph nodes. The contentment with continence was dependent on surgical technique, there was no evident correlation to lymph node spread and adjuvant therapy, respectively. In summary, the correlation between preoperative parameters and positive lymph nodes could clearly be affirmed. With regard to the examined prognostic parameters, there were tendencies identifiable. Henceforth, there is necessity of accurate evaluation of these parameters in prospective studies with long follow-up-intervals and very big patient numbers. The data base containing the prostate cancer patients of the University Marburg established for this study, will be administered and enlarged with all patients operated in this department in the future, so that there will be possibility of accomplishment of further studies with longer follow-ups and increased patient numbers.