Long-term outcomes and late complications of intracranial germinoma: Implications for follow-up policy.

Background: We retrospectively assessed the long-term efficacy, safety, and functional outcome of chemotherapy and radiotherapy (RT) in patients with intracranial germinoma (iGE). Methods: A total of 160 patients with iGE treated between 1983 and 2013 were reviewed. Overall survival (OS) was estimated using Kaplan-Meier method. The cumulative incidence of recurrence (CIR), and secondary malignancies (CISM) were analyzed using cumulative incidence functions (CIFs), with death without the event of interest treated as a competing risk. Functional outcomes were assessed using the Karnofsky Performance Scale (KPS). Cox proportional hazards regression was used to analyze predictive factors. Results: The mean follow-up duration was 157.1 months. The 5-/10-year OS rates were 93.8% and 88.6%. The 5- and 10-year CIRs were both 5.6%, whereas the CISM were 0.6% and 2.1%, respectively. Secondary malignancies developed in 14 patients, most commonly glioblastoma. Thirty-one patients died from disease-, treatment-, or secondary malignancy-related causes. Additional causes of death were identified during long-term follow-up, even more than 20 years after treatment. Functional outcomes remained favorable (KPS ≥ 60) in 90.6% at 5 years and 88.5% at 10 years. Chemotherapy combined with reduced extent and reduced-dose RT significantly improved OS without increasing the CIR. Conclusions: Despite the generally favorable prognosis, secondary malignancies and disease- and treatment-related long-term adverse effects significantly affect patient outcomes in iGE. Long-term follow-up (over 20 years) is essential for detecting and managing these complications. Chemotherapy with reduced-extent and reduced-dose RT may help minimize long-term adverse effects.