Background: Approximately 75 % of patients with testicular seminoma present with stage I disease, and the probability of long-term survival approaches 100 %. However, the standard adjuvant treatment for stage I seminoma patients remains controversial, and there is no uniform consensus in the literature. The present study was performed to evaluate treatment preference and outcomes for men with stage I testicular seminoma.
Materials and methods: From 1997 to 2013, 282 patients with histologically confirmed stage IA and IB testicular seminoma who underwent orchiectomy were included. The outcomes of three management options and survivals were retrospectively analyzed. The prognostic significance of risk factors for relapse on survival was evaluated by univariate and multivariate analysis; in addition, the factors predicting relapse were also evaluated by logistic regression analysis.
Results: Of the 282 patients with stage I seminoma, 130 (46.1) received adjuvant radiotherapy (RT), 80 (28.4 %) were treated with adjuvant carboplatin, while the remaining 72 patients (25.5 %) underwent surveillance. At the time of analysis, the median follow-up period of 38.5 months; relapses were observed in 16 patients (22.3 %) on surveillance, in one patient (1.2 %) treated with adjuvant carboplatin and in ten patients (%7.7) who received adjuvant RT. The 5-year disease-free survival (DFS) rate for patients who underwent surveillance was worse than those of patients treated with adjuvant carboplatin and RT (64.2 vs. 97.7 vs. 91.9 %, respectively; p < 0.001). However, the 5-year overall survival (OS) rate for patients on surveillance was similar compared with the adjuvant treatment groups (100 vs. 92.3 vs. 97.4 %, respectively; p = 0.44). Univariate analysis showed that only the treatment approach (surveillance vs. adjuvant carboplatin vs. adjuvant RT) for DFS (p < 0.001), invasion of the rete testis (p = 0.041) and the presence of relapse (p < 0.001) for OS were important prognostic indicators. Multivariate analysis indicated that the treatment strategy for DFS (p < 0.001, HR 0.34) was an independent prognostic factor. Furthermore, a logistic regression analysis showed that adjuvant treatment was found to be an independent factor for predicting relapse (p = 0.004, odds ratio: 0.39).
Conclusions: Our results indicate that adjuvant treatment with carboplatin or RT is associated with improved DFS compared with surveillance for men with stage I testicular seminoma after orchiectomy. Moreover, the treatment strategy is an important prognostic indicator for DFS and a predictive factor for relapse. Although adjuvant treatment, especially carboplatin, seems to be a suitable treatment for patients with risk factors for relapse, surveillance is still feasible and the preferred management option after radical orchiectomy in men with stage I seminoma. More reliable predictive factors are needed to make treatment decisions.
Keywords: Adjuvant treatment; Carboplatin; Radiotherapy; Seminoma; Surveillance; Survival.