Proton therapy for adult craniopharyngioma: experience of a single institution in 91 consecutive patients

Background Craniopharyngioma (CP) in adults is a rare benign tumor associated with many morbidities, with limited contemporary studies to define treatment, and follow-up guidelines. Methods A single-center retrospective study was conducted on patients aged >= 18 years from 2006-2018 with CP and who were treated with proton therapy (PT). Late toxicity was defined as a minimum of 18 months from diagnosis. Overall survival (OS), local recurrence-free survival (LRFS), and toxicity were characterized using Kaplan-Meier and Cox regression analyses. Results Ninety-one patients met the criteria, with a median age of 37 years (range 18-82 years). PT was conducted after tumor resection in 88 patients (97%), in 64 patients (70.3%) as an adjuvant strategy and in 27 (29.7%) after recurrent disease. Three patients received exclusive PT. A median MRI follow-up of 39 months revealed 35.2% complete response, 49.5% partial response, and 9.9% stable disease. Five patients developed local recurrence (LR). The pattern of failure study showed that these five LR were within the GTV volume. The 5-year LRFS was 92.0% [CI 95% 84.90-99.60]. All the patients were alive at the end of the follow-up. Patients requiring treatment adaptation during PT tend to have a higher risk of LR (P = .084). Endocrinopathy was the most frequent grade >= 2 late toxicity. Among patients who were symptom-free before the start of treatment, none developed hearing toxicity but four (9.8%) developed visual disorders and 10 (11.3%) symptomatic memory impairment. Patients with large tumors had a higher risk of developing symptomatic memory impairment (P = .029). Conclusion Adults with CP treated with PT have favorable survival outcomes, with acceptable late toxicity. Prospective quality-of-life and neurocognitive studies are needed to define late adverse effects better.

Automated summary

This study retrospectively analyzed the outcomes of adults with craniopharyngioma treated with proton therapy. The results showed that proton therapy had favorable survival outcomes with acceptable late toxicity. Patients with large tumors and those requiring treatment adaptation had a higher risk of recurrence and adverse effects.