The Total Number of Retroperitoneal Lymph Nodes Resected Impacts Clinical Outcome After Chemotherapy for Metastatic Testicular Cancer

Abstract

To evaluate the prognostic significance of the total number of lymph nodes obtained at postchemotherapy retroperitoneal lymph node dissection (PC-RPLND). After the multidisciplinary management of metastatic germ cell tumor, approximately 10%-15% of patients with the histologic finding of fibrosis or teratoma will suffer disease recurrence. Between 1989 and 2006, a total of 628 patients underwent PC-RPLND and were found to have either fibrosis or teratoma. After Institutional Review Board approval, complete clinical and pathologic data were obtained from our prospective testis cancer surgical database. A Cox proportional hazards regression model was constructed to evaluate the association of the total number of lymph nodes obtained at PC-RPLND on disease recurrence. On pathologic evaluation, 248 (57%) patients had fibrosis and 184 (43%) patients had teratoma. The median number of lymph nodes resected was 25 (interquartile range, 15-37). On multivariable analysis, increasing postchemotherapy nodal size and decreasing lymph node counts were significant predictors of disease recurrence (P=.01, .04, respectively). For patients with 10 nodes removed, the predicted 2-year relapse free probability was 90%, compared with 97% when 50 nodes were removed. Our data suggest that the total number of lymph nodes removed and analyzed is an independent predictor of disease recurrence after PC-RPLND. This has implications both for the urologist to assure completeness of resection and for the pathologist to meticulously assess the pathologic specimens.