Rete Testis Invasion Is Consistent With Pathologic Stage T1 in Germ Cell Tumors

Abstract

Objectives: Rete testis invasion by germ cell tumors is frequently concomitant with lymphovascular or spermatic cord invasion (LVI/SCI); independent implications for staging are uncertain.

Methods: In total, 171 seminomas and 178 nonseminomatous germ cell tumors (NSGCTs; 46 had 1%-60% seminoma component) came from five institutions. Metastatic status at presentation, as a proxy for severity, was available for all; relapse data were unavailable for 152. Rete direct invasion (ReteD) and rete pagetoid spread (ReteP) were assessed.

Results: ReteP and ReteD were more frequent in seminoma than NSGCT. In seminoma, tumor size bifurcated at 3 cm or more or less than 3 cm predicted metastatic status. Tumors with ReteP or ReteD did not differ in size from those without invasions but were less than with LVI/SCI; metastatic status or relapse did not show differences. In NSGCT, ReteP/ReteD did not correlate with size, metastatic status, or relapse.

Conclusions: Findings support retaining American Joint Committee for Cancer pathologic T1 stage designation for rete testis invasion and pT1a/pT1b substaging of seminoma.

Keywords: Epididymis; Nonseminomatous germ cell tumor; Pathologic stage; Rete; Seminoma; Testis.