ABSTRACT
Background: We aim to better characterize stereotactic body radiation therapy (SBRT)-related hepatic biochemical toxicity in patients with multiple intrahepatic lesions from hepatocellular carcinoma (HCC). Methods: We conducted a retrospective analysis of patients with HCC who underwent SBRT for 2 or more synchronous or metachronous liver lesions. We collected patient characteristics and dosimetric data (mean liver dose [MLD], cumulative effective volume [Veff], cumulative volume of liver receiving 15 Gy [V15Gy], and cumulative planning target volume [PTV]) along with liver-related toxicity (measured by albumin-bilirubin [ALBI] and Child-Pugh [CP] scores). A linear mixed-effects model was used to assess the effect of multi-target SBRT on changes in ALBI. Results: There were 25 patients and 56 lesions with median follow-up of 29 months. Eleven patients had synchronous lesions, and 14 had recurrent lesions treated with separate SBRT courses. Among those receiving multiple SBRT courses, there were 7 lesions with overlap of V15Gy (median V15Gy overlap: 35 mL, range: 0.5-388 mL). There was no association between cumulative MLD, Veff, V15Gy, or PTV and change in ALBI. Four of 25 patients experienced non-classic radiation-induced liver disease (RILD), due to an increase of CP score by ≥2 points 3 to 6 months after SBRT. Sixteen of 25 patients experienced an increase in ALBI grade by 1 or more points 3 to 6 months after SBRT. Comparing the groups that received SBRT in a single course versus multiple courses revealed no statistically significant differences in liver toxicity. Conclusion: Liver SBRT for multiple lesions in a single or in separate courses is feasible and with acceptable risk of hepatotoxicity. Prospective studies with a larger cohort are needed to better characterize safety in this population.
ABSTRACT
BACKGROUND: Radiation therapy is a common treatment for meningiomas. Volume changes of meningiomas in response to radiation are not well characterized. This study seeks to quantify the volume change of meningiomas following radiation. METHODS: Data were collected from a retrospective single-institution database of cases from 2005-2015. Tumors were measured using T1-weighted post-contrast magnetic resonance imaging. Volumes were calculated using the ABC/2 ellipsoidal approximation. RESULTS: A total of 63 patients fit the inclusion criteria; 37 patients (59%) received radiation following resection, 19 (30%) received radiation alone, 4 (6%) received radiation following a biopsy, and 3 (5%) had unknown surgical status. A total of 39 patients (62%) had skull base meningiomas; 43 tumors were World Health Organization (WHO) grade I, and 12 tumors were WHO grade II. Thirteen patients received radiosurgery, 43 received radiotherapy, and 7 received an unknown number of treatments. Eight patients did not attain local control and were excluded from volume analyses. WHO grade I meningiomas saw an average of 33% ± 19% decrease in tumor volume; WHO grade II tumor volumes decreased by an average 30% ± 23%. Radiosurgery saw an average volume decrease of 34% ± 13%, while radiotherapy resulted in volume decrease of 31% ± 21%. For those who achieved local control, there was an average decrease in tumor size of 30% ± 19%, 30% ± 22%, and 41% ± 19% over 0.5-1.5, 2.5-3.5, and >5 years, respectively. CONCLUSIONS: Meningiomas treated with radiation exhibit nonlinear decrease in size over time. The greatest decrease in tumor volume occurs within the first year and begins to plateau 5 years post-radiation treatment.
