Optimal Timing of VVhole-Brain Radiation Therapy Following Craniotomy for Cerebral Malignancies

BACKGROUND: For patients with cerebral metastases that are limited in number, surgical resection followed by whole-brain radiation therapy is the standard of care. In addition, for high-grade gliomas, maximal Surgical resection followed by local radiotherapy is considered the optimal treatment. Radiation is known to impair wound healing, including healing of surgical incisions. Radiotherapy shortly after surgical resection would be expected to minimize the opportunity for tumor regrowth or progression. Owing to these competing interests, the purpose of this study was to shed light on the optimal timing of radiotherapy after surgical resection of brain metastasis or high-grade gliomas. METHODS: A review of the literature was conducted on the following topics: radiation and wound healing, corticosteroid use and wound healing, radiotherapy for tumor control for cerebral metastases and high-grade gliomas, and whole-brain radiation therapy or focal radiotherapy after craniotomy with focus on the timing of radiotherapy after surgery. RESULTS: In animal models, wound integrity and healing was less impaired by radiotherapy administered 1 week after surgery. In humans, this timing would be expected to be significantly longer, on the order of several weeks. CONCLUSIONS: Given the limited literature, insufficient conclusions can be drawn. However, animal data suggest a period of at least 1 week (but it is likely several weeks in humans) is necessary for reconstitution of wound strength before initiation of radiation therapy. A randomized prospective study is recommended to understand better the effect of the timing of radiation therapy following surgical intervention for brain metastasis or high-grade gliomas.