Neuropsychological performances in patients with infiltrative non-GBM gliomas after postoperative adjuvant photon or proton radiotherapy: A prospective and preliminary investigation

Abstract

Infiltrative non-GBM gliomas are common primary intracranial malignancies, and postoperative adjuvant radiotherapy is recommended for most adult patients diagnosed with this disease to enhance local control and prolong intracranial progression-free survival (PFS). However, RT-related neurocognitive function (NCF) consequences should not be ignored. Early neurocognitive decline principally includes episodic memory, associated significantly with functions of the hippocampus. This prospective study aims to investigate the impact of adjuvant brain irradiation on neurocognitive performances and relevant oncological outcomes.

Twenty-five patients with intracranial infiltrative non-GBM gliomas were enrolled when postoperative adjuvant RT was recommended. All recruited patients should receive baseline brain magnetic resonance imaging, and neuropsychological assessments before and 4 months after the RT course. A battery of neuropsychological measures, mainly including executive functions, memory, psychomotor speed and visuoconstructive ability, was used to evaluate NCFs of interest.

Analyzing the delta values between post-irradiation and baseline NCF scores, we observed a robust trend reflecting cognitive stabilization rather than deterioration in almost all NCF. Both verbal and visual memory functions exhibited significant differences in the corresponding scaled scores (Z = −2.722, p = .006, regarding verbal memory; Z = −2.246, p = .025, concerning non-verbal memory). Moreover, patients' neuropsychological performances associated with psychomotor speed and executive functions also disclosed a tendency toward stabilization/improvement.

This prospective study demonstrated that patients with infiltrative non-GBM exhibited a marked tendency toward neurocognitive stabilization after receiving postoperative adjuvant RT.

Clinical trial registration: Trial Registration with ClinicalTrials.gov identifier: NCT03534050

Keywords:

• Hippocampus
• infiltrative non-GBM gliomas
• neurocognitive functions
• radiation therapy

Acknowledgements

The authors are considerably thankful to Ms. Hsin-Yi Chen, Case Manager at Cancer Center of Chang Gung Memorial Hospital, Linkou for assisting our neurocognitive research team in patient recruitment, nursing follow-up, and clinical data acquisition.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the [Chang Gung Memorial Hospital] at Linkou, Taiwan, R.O.C. under Grant [CMRPG3G1773] and [CMRPG3J1012].