Risk factors for relapse in patients with stage I testicular seminoma.

Abstract

e17011 Background: The relapse rate for patients with clinical stage I seminoma is approximately 20% and surveillance is strongly preferred. Risk- adapted management with adjuvant carboplatin chemotherapy is another option for those at high risk of relapse but no consensus on high risk factors has yet been determined. Tumour size > 4 cm, lymphovascular and rete testis invasion have been inconsistently associated with the risk of relapse. In our centre all patients with stage I seminoma are managed with surveillance wich gives us the opportunity to investigate risk factors for relapse. The aim of this study was to investigate the association of tumour size, lymphovascular invasion and rete testis invasion with the risk of relapse in patients with stage I seminoma. Methods: We identified patients with clinical stage I seminoma diagnosed between 2010 and 2020 who had tumour size, lymphovascular invasion and rete testis invasion reported in their medical record. Relapse rate was rhe primary outcome and the variables for relapse were tumour size > 4, lymphovascular invasion and rete testis invasion. To evaluate this variables The Cox proportional hazard model was built. Results: In total, 97 patients were evaluated. Median age of the population was 36 years (range 22- 56 years). 29 patients (29.8 %) relapsed and the median relapse time was 16 months (range 3 -57 months). Median follow- up time for patients without relapse was 9.3 years. Lymphovascular invasion and tumour size > 4 were statistically significant and independent risk factors for relapse. Lymphovascular invasion was associated with approximately 2,38 times higher risk of relapse. Tumour size > 4 cm was associated with 2,6 times higher risk of relapse and was the strongest predictor of relapse. Rete testis invasion slightly increased the risk of relapse but this was not statistically significant. Results are shown in Table 1. Conclusions: Tumour size and lymhpovascular invasion were independent factors associated with increased risk of relapse while rete testis invasion was not. The strongest risk factor for relapse was tumour size > 4 cm which is consistent with previous studies. Since the risk of relapse for stage I seminoma is acceptably low and disease specific- survival high surveillance is the preferred option. For patients not suitable for surveillance risk-adapted management with well defined risk factors can be useful in clinical practice. Results. Variable coef HR (exp(coef)) SE(coef) z p-value Lower 95% CI Upper 95% CI Lymphovascular invasion 0,8665 2,3785 0,3848 2,25 0,0245 1,1187 5,0645 Tumour size > 4 cm 0,9498 2,5852 0,3807 2,49 0,0128 1,2227 5,4627 Rete testis invasion 0,2002 1,2217 0,4087 0,49 0,6234 0,5516 2,7061 HR = hazard ratio; CI = confidence interval.