The use of stereotactic radiosurgery to treat multiple intracranial metastases, frequently concurrently, has become increasingly common. The ability to accurately and safely deliver stereotactic radiosurgery treatment to multiple intracranial metastases (MIM) relies heavily on the technology available for targeting, planning, and delivering the dose. A number of platforms are currently marketed for such applications, each with intrinsic capabilities and limitations. These can be broadly categorised as cobalt-based, linac-based, and robotic. This review describes the most common representative technologies for each type along with their advantages and current limitations as they pertain to the treatment of multiple intracranial metastases. Each technology was used to plan five clinical cases selected to represent the clinical breadth of multiple metastases cases. The reviewers discuss the different strengths and limitations attributed to each technology in the case of MIM as well as the impact of disease-specific characteristics (such as total number of intracranial metastases, their size and relative proximity) on plan and treatment quality.

No abstract

Surgery usually represents the standard treatment of Thymoma with neoadjuvant or adjuvant chemoradiotherapy in locally advanced stages.Frequently the recurrences of disease appears on the pleura. The relative radiosensitivity of thymomas and the small tendency to systemic spread offer curative possibility to local eradicative therapies.We have evaluated in terms to local control, OS and toxicity the SABR directed to all sites of relapses. Materials/Methods: Between April 2014 and Dicember 2016, 14 pts with thymoma underwent SABR for pleural relapses Median age was 43 ys, with KPS >90. 9 pts presented myasthenia gravis at diagnosis, at the onset all patients were treated by surgery .Thymic epithelial tumours were staged according to the Masaoka-Koga staging system, 8/14 pts were stage B3, 4/14 pts were stage B2, 1/14 was B1, 1/14 was stage AB. Relapses in pleural regions were detected by CT in 100% pts, and PET-CT in 86% pts. 50% pts were treated with somatostatin analogue and all pts received corticosteroid. 51 lesions were treated with SABR. SBRT was delivered by 6MV Linac using beam modulator equipped with 4 mm MLC, through two coplanar arcs with VMAT optimization. Median GTV volume was 36.6 cc (2-173 cc). The prescription dose was 30Gy/3fx , 26 Gy /1fx , 24 Gy/3fx to the 80% isodose, in 39/51, 6/51, 7/51 lesions respectively. Setup and isocenter position was controlled before each fx using CBCT .The response was evaluated 60 days after SBRT by CT and PET scan and every 4 months successively.Toxicity was assessed by CTCAE score. Results: Only 12/14 pts and 39/51 lesions have been evaluated for response. Median FU was 19.28 (range 7-37) months the median survival was 17.7 months. All Pts are still alive and all lesions treated are in complete response. 6/12 pts had relapses outside of treatment sites, these recurrences were treated by SABR. Only grade 2 pneumonitis occurred in 1 pts, who underwent to SBRT for three ipsilateral pleural lesions simulataneously. Conclusion: In our experience SABR appears safe and effective for curative treatment of thymoma relapses. The LC of 100% of primary and following relapses and the disease chest limited lead to curative effect of SABR. All pts are still alive without any evidence of disease. The high conformity of dose distribution using VMAT limits the treatment relate toxicity.

No abstract

No abstract