512MO - Outcomes of relapsed clinical stage I versus de novo metastatic testicular cancer patients: An analysis of the IGCCCG Update database

Background

Between 60-70% of patients with germ-cell tumors (GCT) present with clinical stage I (CSI) disease. Active surveillance after orchiectomy is the preferred management but is associated with a 15 to 30% relapse rate. We compared the outcomes of patients relapsing from CSI to the ones of similar patients presenting with de novo metastatic disease.

Methods

We identified in the IGCCCG Updated database all patients with gonadal disseminated GCT who had complete information on initial tumor stage whether CSI or de novo metastatic. Patients relapsing from initial CSI were compared to patients with de novo metastatic GCT. Progression-free survival and overall survival at 5 years (5y-PFS and 5y-OS) were estimatedby the Kaplan-Meier method and compared with the hazard ratio (HR).

Results

A total of 1014 seminoma (S) [298 (29.4%) relapsing from CSI, 716 (70.6%) de novo] and 3103 non-seminoma (NS) [626 (20.2%) relapsing from CSI, 2477 (79.8%) de novo] patients were identified. No statistically significant differences in PFS and OS were found between patients relapsing from CSI and de novo metastatic disease for S patients (5y-PFS 87.6% versus 88.5% and 5y-OS 93.2% versus 96.1%). For NS patients there was no difference in outcome between relapsing and de novo patients within the same IGCCCG group (HR=0.89; 95% CI: 0.70-1.12). IGCCCG group was more favorable in NS patients relapsing from CSI: (good risk: 82.1% vs 51.4%) and equal in S patients (good risk: 96.3% vs 96.4%). Nevertheless 112/626 (18%) NS and 11/298 (4%) S CSI patients relapsed with intermediate or poor IGCCCG group.

Conclusions

We found no differences in PFS or OS at 5 years in patients relapsing from initial CSI as compared to de novo metastatic patients within the same IGCCCG prognostic group. However, a substantial proportion of CSI patients relapsed with intermediate or poor prognostic features with a need of intensified treatment. The study underlines the importance of improving active surveillance techniques and schedules to detect recurrence as early as possible in CSI patients and to avoid unnecessary toxicity.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The International Germ Cell Cancer Collaborative Group (IGCCCG).

Funding

EORTC.

Disclosure

All authors have declared no conflicts of interest.