Assessment of new prognostic risk models for recurrence in patients with clinical stage I seminoma

To evaluate two new prognostic risk models aimed at improving clinical decision-making in patients with clinical stage (cS) I seminomatous testicular germ cell tumours (GCTs), 5%-30% of whom experience recurrence during surveillance after orchiectomy and may benefit from adjuvant therapy.

In this exploratory study, patients with unilateral cS I seminoma, normalised serum tumour markers after orchiectomy, no adjuvant therapy and at least 12 months of follow-up were included. Cox regression analysis was applied to evaluate the prognostic factors proposed by the Danish Testicular Cancer Database (DaTeCa) and the European Association of Urology (EAU), and recurrence probabilities were estimated using the Kaplan-Meier method.

Among 139 patients, 25 (18%) experienced recurrence within a median follow-up of 37 months (95% confidence interval 47.9-63.1 months). Multivariable analysis confirmed only rete testis infiltration as an independent predictor of recurrence (P = 0.039), while other prognostic factors included in the DaTeCa risk model (i.e. hilar soft tissue invasion, rete testis infiltration, lymphovascular invasion, and elevated pre-orchiectomy human chorionic gonadotropin and lactate dehydrogenase) and the EAU model (i.e. tumour size, rete testis infiltration and lymphovascular invasion) were not. However, 5-year recurrence risks for the different risk groups, defined by the combination of prognostic factors, aligned well with the DaTeCa (no risk factors: 4% vs 6%; all risk factors: 67% vs 62%) and the EAU risk models (low [13% vs 8%] and intermediate risk [22% vs 20%]). A discrepancy was observed in EAU high-risk cases (67% vs 44%), which was probably attributable to the very small number of patients in our high-risk subgroup (n = 6 [4.3%]).

The DaTeCa and EAU risk classification models demonstrated overall consistency in our exploratory cohort and may aid in identifying patients with cS I seminoma who are at high risk for recurrence and who might be candidates for adjuvant therapy. Further multicentre validation studies are needed.