Title:
Lymph Node Yield in Primary Retroperitoneal Lymph Node Dissection for Nonseminoma Germ Cell Tumors.

Abstract:
The number of lymph nodes removed at surgery for various malignancies has diagnostic and prognostic value. However, there are limited data on the significance of the number of nodes removed at retroperitoneal lymph node dissection performed for testicular nonseminoma germ cell tumors.
From 1979 to 2012 primary open retroperitoneal lymph node dissection was performed by a single experienced surgeon for clinical stage I/II testicular nonseminoma germ cell tumor in 157 patients. Node count was available in 111 cases (71%). Factors associated with total node count and nodes with viable cancer were assessed by linear regression. The association between node count and time to relapse was assessed by multivariate Cox proportional hazards models controlled for adjuvant chemotherapy.
The median total lymph node count was 28 (IQR 19-38). Patient age, cancer laterality, body mass index, clinical stage, time from orchiectomy to retroperitoneal lymph node dissection, pathologist and lymph node dissection year were not associated with total lymph node count. A viable germ cell tumor was found in 70 patients (63%). Total node yield was not associated with nodal cancer metastasis. After lymph node dissection 17 patients (16%) received adjuvant chemotherapy. At a median 57-month followup 18 cases (17%) relapsed after primary retroperitoneal lymph node dissection. Increasing total node count was associated with a decreased risk of relapse on univariate and multivariate analysis (HR 0.96, 95% CI 0.92-0.99, p = 0.03 and HR 0.94, 95% CI 0.89-0.99, p = 0.017, respectively).
No analyzed clinical or pathological variable was associated with the node yield of primary retroperitoneal lymph node dissection. However, there may be a relationship between the total node yield at retroperitoneal lymph node dissection and the risk of relapse.