Histologic type, staging, and distribution of germ cell tumors in Korean adults

Objectives: To investigate the presentation of germ cell tumors (GCT) in terms of histology and stage, to better clarify the epidemiology of this disease in eastern Asia. Methods: Six hundred ninety-eight patients diagnosed with GCT between 1995 and 2004 were analyzed. Clinical parameters at the time of initial diagnosis were classified in terms of the American Joint Committee on Cancer (AJCC) tumor, nodes, metastasis staging (TNMS) system, the International Germ Cell Cancer Collaborative Classification (IGCCC), for high-risk stage I nonseminomatous GCT (NSGCT) of testis. Results: The anatomic distributions for the primary sites of the observed tumors were as follows: testis 471 cases (67%); central nervous system (CNS) 137 cases (20%); mediastinum 78 cases (11%), and retroperitoneum 12 cases (2%); 239 (51%) of 471 tumors with testicular primary were seminoma. High risk vs. non-high risk stage I NSGCT cases were 62 vs. 58. Of NSGCT of testis, 129 (58%), 73 (33%), and 21 (9%) of tumors presented with good, intermediate, and poor prognosis, respectively, based on IGCCC, whereas 231 (99%) patients were classified with a good prognosis and 3 (1%) with an intermediate prognosis amongst seminomas of testis; 193 (82%) cases presented as stage I testicular seminoma whereas 120 (54%) cases presented as stage I NSGCT. Conclusions: Extragonadal primary GCTs are very common in Korean. Incidence of high risk NSGCT of testis with stage I disease was lower than in the Western report. NSGCT presents itself as a more aggressive form whereas seminoma is a very indolent tumor when compared with cases in Western countries.