The spectrum of radiation therapy options for craniopharyngioma: a systematic review

Craniopharyngiomas (CPs) are rare, slow-growing brain tumors which originate in the sellar region. CPs may present with symptoms secondary to compression of surrounding structures, particularly the pituitary gland, and surgical removal has traditionally been the mainstay of treatment. However, due to high recurrence rates for CPs, especially when gross total resection is not feasible, radiotherapy has played an increasingly significant role in their management. Here, we review radiation modalities, treatment settings, and future directions in the management of CP. In addition, we outline emerging therapeutic combinations involving targeted therapies.

A systematic review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A search of the MEDLINE/PubMed, Embase, and Web of Science databases was used for initial identification of articles. Included studies were then grouped into the following treatment modalities: conventional radiotherapy (CRT), intensity-modulated radiotherapy (IMRT), proton therapy, fractionated stereotactic radiotherapy (FSRT) /stereotactic radiosurgery (SRS), and brachytherapy.

A total of 60 studies met inclusion criteria, comprising 3041 patients, with a median sample size of 33 (range: 10-242) and age ranging from 6 to 55. This review included 8, 15, 3, 12, and 29 reports corresponding to brachytherapy, CRT, IMRT, proton therapy, and FSRT/SRS, respectively. Proton therapy and FSRT had the highest median 5-year progression-free survival (PFS), with rates of 92% and 89%, respectively. IMRT and proton therapy were primarily investigated in pediatric patients (median ages of 8.2 and 10.3 years, respectively). By comparison, FSRT and SRS research has mainly been in adult cohorts.

Precision radiotherapy appears to be associated with high rates of tumor control in CP, suggesting these approaches bear further investigation. Selection of the appropriate radiation modality from those reviewed likely depends on several patient-specific factors. Important considerations include tumor location and volume, patient age, prior treatments for CP, and patient preference.