This study examined cFLIP expression in germ cell tumors (GCTs) and thymoma originating from the mediastinum.
A retrospective study included 46 consecutive patients with GCTs conducted between 1983 and 2005, and 22 consecutive thymoma in the mediastinum whose tumors had been surgically excised. CFLIP was studied immunohistochemically in 46 patients with mediastinal GCTs.
The 46 primary GCTs in mediastinum included teratoma (n = 27; 58.7%), seminoma (n = 10; 21.7%), yolk sac tumor (n = 6; 13%), embryonal carcinoma (n = 1; 2.1%), and mixed GCTs (n = 2; 4%; one consisted of teratoma and yolk sac tumor, and the other teratoma, yolk sac tumor and seminoma); and 22 thymoma including WHO type A (n = 3, 13.6%), type AB (n = 4, 18.2%), type B1 (n = 6, 27.3%), type B2 (n = 4, 13.6%), and type B3 (n = 5, 22.7%). Each tumor was examined with hematoxylin and eosin staining, and with antibodies to CFLIP. All 10 seminoma cases, 1 embryonal carcinoma case, and 1 mixed GCT case containing seminoma were immunopositive for CFLIP. In the other hand, the 22 thymoma, 6 yolk sac tumor, 27 teratomas and 1 case with mixed GCT without component of seminoma were immunonegative for CFLIP.
We conclude that immunostaining with antibodies to CFLIP is a useful diagnostic tool in the identification of seminomas and primary embryonal carcinomas in GCTs originating from the mediastinum.
CFLIP is a useful diagnostic tool in the identification of seminomas and primary embryonal carcinomas in GCTs originating from the mediastinum.
Pao-Hsien Chu, No Financial Disclosure Information; No Product/Research Disclosure Information