Outcomes of active surveillance of clinical stage I non-seminomatous germ cell tumors: sub-analysis of the multi-institutional nationwide case series of the Japanese Urological Association

To evaluate the survival rate and risk factors of distant metastasis in stage I non-seminomatous germ cell tumor (NSGCT) cases without adjuvant treatments.A national testicular cancer survey of cases newly diagnosed in 2005 and 2008 was conducted by the Japanese Urological Association in 2011. In 159 stage I NSGCT cases, 132 were followed by active surveillance after high orchiectomy. Their recurrence-free survival rate (RFS) was compared with 27 cases that received adjuvant treatments, and clinical and pathological parameters were explored to identify significant risk factors of recurrence.Within a median follow-up period of 30.3 months (range: 0.3-65.6 months), 16 (12.1%) of the 132 surveillance cases relapsed at 2.8-51.2 months after high orchiectomy (median: 8.35 months). The 2-year RFS rate was 90%. Eleven (68.8%) cases relapsed within 1 year, and five (31.3%) cases relapsed in 3 years or more. Half (50%) of the recurrences were detected by imaging studies alone, 37.5% by imaging combined with tumor markers, and 12.5% by tumor marker elevation alone. The only significant risk factor of recurrence was the existence of embryonal carcinoma elements in the primary testicular tumor (P = 0.0068). There was no significant difference in RFS between cases with active surveillance and adjuvant treatments.The present report is the first large scale study of clinical stage I NSGCTs in Japan. Active surveillance appears to be an effective treatment option for patients with clinical stage I NSGCTs.