Role of radiotherapy in organ-sparing treatment of seminoma

Radiotherapy after testis-sparing surgery for seminoma in monorchid patients: safety and efficacy

PURPOSE

To evaluate local control and longitudinal endocrine data in monorchid patients treated with testicular-sparing surgery and adjuvant radiotherapy (RT) for seminomatous germ-cell tumors.

METHODS

We searched our database established in 2009 for patients with seminoma who received testis irradiation following partial orchiectomy up to 2018. Eleven patients were identified. All had associated germ cell neoplasia in situ (GCNIS) in surrounding parenchyma. Analysis focused on local control and testosterone levels preservation after RT. We considered age, baseline (pre-RT) testosterone and luteinizing hormone (LH) levels, residual testicular volume, tumor size, and testosterone and LH levels trend over time in order to identify any association with endocrine impairment leading to hormonal replacement need.

RESULTS

After a median follow-up of 21 months, no local or distant relapses were observed and hormonal function was maintained in 54.5% of patients (6/11). No significant interactions were observed for the investigated covariates. Notably, we observed an association between higher baseline testosterone levels and a decreased risk of exogenous androgen replacement (hazard ratio [HR] 0.409, 95% confidence interval [CI] 0.161-1.039, p = 0.060), whereas tumor size was associated with an increased risk of exogenous androgen replacement (HR 1.847, 95% CI 0.940-3.627, p = 0.075).

CONCLUSIONS

Radiotherapy after testicular sparing surgery is effective in preventing local disease relapse in presence of GCNIS in the medium term. This strategy allows a preservation of adequate endocrine function in about half of patients. More patients and longer follow-up are needed to confirm these findings.

Long-term cardiovascular complications in stage I seminoma patients

PURPOSE

The cure rate of stage I seminoma patients is close to 100% and so the recent focus of clinical research has shifted onto the prevention of treatment-related complications. We assessed long-term cardiovascular complications and identified risk factors for cardiovascular events (CVEs) in stage I seminoma patients.

METHODS

This retrospective cohort study included 406 consecutive stage I seminoma patients. Primary endpoint was CVE rate.

RESULTS

During a median follow-up of 8.6 years, we observed 23 CVEs in 406 patients [10-year CVE risk 5.6% (95% CI 3.2 to 8.8)]. In univariable competing risk analysis, higher age, positive smoking status, history of diabetes and hypertension were significantly associated with the occurrence of CVE. In multi-state analysis, new onset of diabetes, hypertension and hyperlipidemia during follow-up predicted for an excessively increased CVE risk. In multivariable analysis adjusting for age and smoking, the development of hypertension and hyperlipidemia after tumor-specific treatment prevailed as risk factors for CVE. Regarding adjuvant treatment modalities, patients receiving adjuvant radiotherapy had a significantly higher probability of CVE than patients receiving adjuvant carboplatin [16% vs. 0%; risk difference (RD) = 16%, 95% CI 6 to 25%, p = 0.001]. This difference prevailed after adjusting for age, follow-up-time, diabetes, hypertension and smoking (RD = 11%, 95% CI 1 to 20%, p = 0.025).

CONCLUSION

We identified a panel of baseline risk factors and dynamically, occurring predictors of CVE in stage I seminoma patients. This information may be used for targeting comorbidity management in these patients. The observed association of adjuvant radiotherapy with higher CVE risk warrants further investigation.