Prediction of Retroperitoneal Histology in Metastatic Nonseminomatous Testicular Cancer Patients after Chemotherapy Based on Clinical and Radiological Parameters

Abstract

Introduction: We retrospectively analysed the predictive value of numerous clinical and radiological parameters to identify a predictor for either necrosis or residual tumors found by retroperitoneal lymph node dissection (RPLND) histology in a collection of nonseminomatous germ cell tumor (NSGCT) patients. Materials and Methods: A database was created containing detailed clinical, radiological and histological information of all consecutive NSGCT patients, who underwent post chemotherapy RPLND between 1984 and 2007. According to the histology of the RPLND specimen, patients were assigned to the “necrosis-only” group or the “residual tumor” group. Associations between clinical and radiological parameters and histology of RPLND were analyzed. Results: Histology of dissected masses showed complete necrosis in 57.4% of patients and residual tumors in 42.6% (3.1% viable cancer and 39.5% teratoma). Univariate analysis showed significant correlation of RPLND histology and the following parameters: teratoma-positive primary tumors, pre-chemotherapy α-fetoprotein (AFP) and – less pronounced – human chorionic gonadotropin levels, size of metastatic mass, total volume of metastatic retroperitoneal lymph nodes, and percentage of volume reduction. The best prediction for necrosis in RPLND histology was in patients with no evidence of teratomatous elements in primary tumors and with normal pre-chemotherapy AFP levels and small lymph nodes. Stepwise multivariate logistic regression analysis confirmed AFP < 10 ng/ml as the best independent predictor for only necrosis in RPLND histology. Conclusions: At the present time we still consider all patients with metastatic NSGCT as candidates for a post-chemotherapy RPLND, arguing that in experienced hands mortality is negligible and morbidity is low and therefore not relevant compared to the risk of missing a residual tumor.