Does the histology of nodal metastasis predict systemic relapse after retroperitoneal lymph node dissection in pathological stage B1 germ cell tumors?

Purpose: We evaluated the prognostic significance of the histology of metastatic lymph nodes to predict postoperative relapse in pathological stage B1 nonseminomatous germ cell tumor (NSGCT). Materials and Methods: A retrospective review of the testicular cancer database was performed to identify all patients with clinical stage A NSGCT who underwent primary retroperitoneal lymph node dissection and were found to have pathological stage B1 disease. No patient received adjuvant chemotherapy and minimal followup was 24 months. Results: A total of 118 patients were identified with a 5-year disease-free survival (DFS) of 68% and a median followup of 43 months. Embryonal cell carcinoma was identified in 92 of 118 (77%) surgical specimens, which was significantly greater than the presence of teratoma (22%), seminoma (16%) and yolk sac (14.4%, p <= 50.001) with no difference in 5-year DFS comparing the presence or absence of each histology. Solitary histology was noted in 88 of 118 patients (74.5%). Embryonal cell carcinoma was the most common single histology identified at surgery at 64 of 88 (73%), with the incidence of seminoma, teratoma and yolk sac being 12.5%, 9.0% and 5.5%, respectively (p <= 0.001). There was no statistical difference in DFS for each of the solitary histological subtypes (p=0.67). Recurrence rates were similar for pure embryonal cell carcinoma (69%), mixed embryonal cell carcinoma (63%) and no embryonal cell carcinoma (73%) in the retroperitoneum (p=0.63). Conclusions: Retroperitoneal histology does not appear to predict outcome in patients with pathological stage B1 NSGCT.