[1014] UTF-1 Is a Novel Diagnostic Marker for Testicular Embryonal Carcinoma and Seminoma

P Wang, RW Allan, CC Guo, Y Peng, PA Humphrey, J Li, D Cao. Beijing Ditan Hospital, Beijing, China; University of Florida, Gainesville; The University of Texas-MD Anderson Cancer Center, Houston; The University of Texas-Southwestern Medical Center, Dallas; Washington University School of Medicine, Saint Louis

Background: The diagnosis of testicular germ cell tumors (GCTs) and their subtyping sometimes can be challenging, especially in metastatic sites. In difficult cases, immunohistochemical markers often needed to achieve this goal. Here we investigated the diagnostic utility of a novel marker UTF-1.
Design: 93 primary [55 pure and 38 mixed, 49 with intratubular germ cell neoplasias (ITGCNs)] and 68 metastatic testicular GCTs (tumor type and component in tables 1 and 2) were retrieved for immunostaining with an UTF-1 antibody. Only nuclear staining was counted as positive. The staining intensity was scored as weak, moderate or strong. The percentage of tumor cells stained was scored semiquantitatively as: 0 (no tumor cell staining), 1+ (<=30%), 2+ (31-60%), 3+ (61-90%), and 4+ (>90%).
Results: The staining results were inTable 1 (primary) and Table 2 (metastatic).

UTF-1 immunostaining in 93 primary testicular GCTs

Tumor type (pure and/or component)	Staining Pattern
	0	1+	2+	3+	4+
ITGCNs (n=49)	0	0	0	0	49 (100%)
classic seminomas (N=49)	0	1 (2%)	3 (6%)	4 (8%)	41 (84%)
Spermatocytic seminomas (n=5)	5 (100%)	0	0	0	0
ECs (N=35)	0	0	0	2 (6%)	33 (94%)
YSTs (N=25)	12 (48%)	8 (32%)	2 (8%)	2 (8%)	1 (4%)
teratomas (N=17)	17 (100%)	0	0	0	0
Choriocarcinomas (N=3)	3(100%)	0	0	0	0

UTF-1 immunostaining in 68 metastatic GCTs

Tumor type	Staining Pattern
	0	1+	2+	3+	4+
Classic seminomas (N=18)	0	1 (6%)	1 (6%)	3 (17%)	13 (71%)
ECs (N=22)	0	0	0	0	22 (100%)
YSTs (N=9)	8 (89%)	1 (11%)	0	0	0
Teratomas (N=14)	14 (100%)	0	0	0	0
Choriocarcinomas (N=5)	5 (100%)	0	0	0	0

The UTF-1 staining intensity was moderate in 1 and strong in 56 embryonal carcinomas (ECs). 67 seminomas demonstrated weak staining in 10, moderate in 32, and strong in 25. The UTF-1 in YSTs was very weak.
Conclusions: UTF-1 is a novel sensitive (100%) diagnostic marker for EC and seminoma. The percentage of tumors demonstrated strong UTF-1 staining was higher in ECs than seminomas (98% versus 37%, P < 0.05). Stuy is in progress to test UTF-1 specificity with non-GCTs.
Category: Genitourinary (including renal tumors)

Monday, March 22, 2010 1:00 PM

Poster Session II # 99, Monday Afternoon