Radiation therapy for childhood-onset craniopharyngioma: systematic review and meta-analysis

Background: Craniopharyngioma (CP), a benign tumor originating from remnants of Rathke's pouch in the sellar region, accounts for approximately 30% of all cases of craniopharyngioma. Radiation therapy has been used to treat CP patients for decades; however, there is still a lack of systematic reviews on the long-term tumor control outcomes in pediatric CP patients treated with external radiation therapy.

Methods: We conducted a comprehensive search of multiple databases for studies on the tumor progression rates of childhood-onset CP(COCP) patients who received external radiotherapy. We also recorded morbidities related to hypopituitarism and vasculopathy. A meta-analysis was performed to calculate the pooled incidence rates. Meta-regression was applied to explore potential sources of heterogeneity in the tumor progression rates.

Results: A total of 22 studies were included after screening and eligibility assessment in accordance with PRISMA guidelines. The median (mean) follow-up period ranged from 2 to 14.9 years. The pooled overall tumor progression rate was 0.10 (95% CI 0.07-0.15). The recurrence rates were 0.14 (95% CI 0.09-0.19) for photon therapy and 0.04 (95% CI 0.01-0.07) for proton therapy. Meta-regression indicated that none of the following underlying risk factors significantly affected the heterogeneity of the recurrence rate: radiation modality (photon vs. proton), median (mean) follow-up duration, or the proportion of patients who did not undergo surgical resection. The pooled incidence of growth hormone deficiency (GHD), thyroid hormone deficiency (THD), adrenocorticotropic hormone deficiency (ACTHD), gonadotropin-releasing hormone deficiency (GnRHD), and diabetes insipidus (DI) were 0.81 (95% CI 0.70-0.90), 0.88 (95% CI 0.79-0.95), 0.69 (95% CI 0.52-0.85), 0.43 (95% CI 0.38-0.49), and 0.56 (95% CI 0.33-0.78), respectively. The pooled morbidity rate for vasculopathy was 0.06 (95% CI 0.04-0.09), with similar rates observed for both photon and proton therapy.

Conclusion: Radiotherapy is a suitable adjuvant or alternative treatment method for childhood CP patients. However, patients inevitably face significant long-term treatment-related complications.