Scalp dosimetry as a predictor of radiation-induced alopecia in primary brain tumours: a retrospective study from a tertiary cancer centre in south India

Introduction: Radiotherapy is essential in treating primary brain tumours, but radiation-induced alopecia (RIA) remains a common side effect that significantly affects patients' quality of life (QOL). With its psychosocial impact on self-image, emotional well-being, and social interactions, alopecia warrants focused attention. This study aims to evaluate the scalp as an organ at risk by defining dose constraints that minimize RIA while maintaining optimal target coverage.Materials and methods: A retrospective analysis was conducted on ۷۰ patients with primary brain tumours who received focal cranial radiotherapy between January ۲۰۲۲ and December ۲۰۲۴. Scalp dose-volume histograms (DVHs) were generated from treatment planning systems, and the mean scalp dose (D mean), maximum scalp dose (D max), median volume of scalp, volume of scalp receiving ≥ ۳۰ Gy (V۳۰Gy), dose received by ۲۰cc (D۲۰cc), and ۳۰cc (D۳۰cc) scalp volume were recorded. RIA was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version ۵.۰. ROC statistical analysis was performed to evaluate the predictive value of scalp dosimetric parameters for RIA severity.Results: The median age of the cohort was ۵۷ years, with a male-to-female ratio of ۱.۰۸:۱. The median D max, D mean, V ۳۰ Gy, D۲۰cc were ۶۰.۴ Gy, ۱۷.۵ Gy, ۱۹.۲%, and ۴۶.۴ Gy, respectively. Grade ۲ and higher RIA was observed in ۶۳% of patients. V۳۰Gy, either independently or in combination with Scalp D mean, was identified as a significant predictor of Grade ۲ or higher RIA.Conclusion: Optimising scalp dose parametric during radiotherapy planning may help mitigate RIA and improve QOL.Introduction: Radiotherapy is essential in treating primary brain tumours, but radiation-induced alopecia (RIA) remains a common side effect that significantly affects patients' quality of life (QOL). With its psychosocial impact on self-image, emotional well-being, and social interactions, alopecia warrants focused attention. This study aims to evaluate the scalp as an organ at risk by defining dose constraints that minimize RIA while maintaining optimal target coverage. Materials and methods: A retrospective analysis was conducted on ۷۰ patients with primary brain tumours who received focal cranial radiotherapy between January ۲۰۲۲ and December ۲۰۲۴. Scalp dose-volume histograms (DVHs) were generated from treatment planning systems, and the mean scalp dose (D mean), maximum scalp dose (D max), median volume of scalp, volume of scalp receiving ≥ ۳۰ Gy (V۳۰Gy), dose received by ۲۰cc (D۲۰cc), and ۳۰cc (D۳۰cc) scalp volume were recorded. RIA was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version ۵.۰. ROC statistical analysis was performed to evaluate the predictive value of scalp dosimetric parameters for RIA severity. Results: The median age of the cohort was ۵۷ years, with a male-to-female ratio of ۱.۰۸:۱. The median D max, D mean, V ۳۰ Gy, D۲۰cc were ۶۰.۴ Gy, ۱۷.۵ Gy, ۱۹.۲%, and ۴۶.۴ Gy, respectively. Grade ۲ and higher RIA was observed in ۶۳% of patients. V۳۰Gy, either independently or in combination with Scalp D mean, was identified as a significant predictor of Grade ۲ or higher RIA. Conclusion: Optimising scalp dose parametric during radiotherapy planning may help mitigate RIA and improve QOL.

کلیدواژه ها:

Scalp dosimetry ، Radiotherapy-induced alopecia ، Primary brain tumours ، VMAT ، QOL