Internal dose escalation associated with increased local control for melanoma brain metastases treated with stereotactic radiosurgery.

Autor:	Kennedy WR; Departments of1Radiation Oncology and., DeWees TA; 2Department of Biomedical Statistics and Informatics, Mayo Clinic, Scottsdale, Arizona; and., Acharya S; 3Department of Radiation Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee., Mahmood M; Departments of1Radiation Oncology and., Knutson NC; Departments of1Radiation Oncology and., Goddu SM; Departments of1Radiation Oncology and., Kavanaugh JA; Departments of1Radiation Oncology and., Mitchell TJ; Departments of1Radiation Oncology and., Rich KM; 4Neurosurgery, Washington University School of Medicine, St. Louis, Missouri., Kim AH; 4Neurosurgery, Washington University School of Medicine, St. Louis, Missouri., Leuthardt EC; 4Neurosurgery, Washington University School of Medicine, St. Louis, Missouri., Dowling JL; 4Neurosurgery, Washington University School of Medicine, St. Louis, Missouri., Dunn GP; 4Neurosurgery, Washington University School of Medicine, St. Louis, Missouri., Chicoine MR; 4Neurosurgery, Washington University School of Medicine, St. Louis, Missouri., Perkins SM; Departments of1Radiation Oncology and., Huang J; Departments of1Radiation Oncology and., Tsien CI; Departments of1Radiation Oncology and., Robinson CG; Departments of1Radiation Oncology and., Abraham CD; Departments of1Radiation Oncology and.
Jazyk:	angličtina
Zdroj:	Journal of neurosurgery [J Neurosurg] 2020 Dec 11; Vol. 135 (3), pp. 855-861. Date of Electronic Publication: 2020 Dec 11 (Print Publication: 2021).
DOI:	10.3171/2020.7.JNS192210
Abstrakt:	Objective: The internal high-dose volume varies widely for a given prescribed dose during stereotactic radiosurgery (SRS) to treat brain metastases (BMs). This may be altered during treatment planning, and the authors have previously shown that this improves local control (LC) for non-small cell lung cancer BMs without increasing toxicity. Here, they seek to identify potentially actionable dosimetric predictors of LC after SRS for melanoma BM. Methods: The records of patients with unresected melanoma BM treated with single-fraction Gamma Knife RS between 2006 and 2017 were reviewed. LC was assessed on a per-lesion basis, defined as stability or a decrease in lesion size. Outcome-oriented approaches were utilized to determine optimal dichotomization for dosimetric variables relative to LC. Univariable and multivariable Cox regression analysis was implemented to evaluate the impact of collected parameters on LC. Results: Two hundred eighty-seven melanoma BMs in 79 patients were identified. The median age was 56 years (range 31-86 years). The median follow-up was 7.6 months (range 0.5-81.6 months), and the median survival was 9.3 months (range 1.3-81.6 months). Lesions were optimally stratified by volume receiving at least 30 Gy (V30) greater than or equal to versus less than 25%. V30 was ≥ and < 25% in 147 and 140 lesions, respectively. For all patients, 1-year LC was 83% versus 66% for V30 ≥ and < 25%, respectively (p = 0.001). Stratifying by volume, lesions 2 cm or less (n = 215) had 1-year LC of 82% versus 70% (p = 0.013) for V30 ≥ and < 25%, respectively. Lesions > 2 to 3 cm (n = 32) had 1-year LC of 100% versus 43% (p = 0.214) for V30 ≥ and < 25%, respectively. V30 was still predictive of LC even after controlling for the use of immunotherapy and targeted therapy. Radionecrosis occurred in 2.8% of lesions and was not significantly associated with V30. Conclusions: For a given prescription dose, an increased internal high-dose volume, as indicated by measures such as V30 ≥ 25%, is associated with improved LC but not increased toxicity in single-fraction SRS for melanoma BM. Internal dose escalation is an independent predictor of improved LC even in patients receiving immunotherapy and/or targeted therapy. This represents a dosimetric parameter that is actionable at the time of treatment planning and warrants further evaluation.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu