Proton beam radiotherapy for uveal melanoma

Abstract

Proton beam radiotherapy of uveal melanoma can be administered as primary treatment, as salvage therapy for recurrent tumor, and as neoadjuvant therapy prior to surgical resection. The physical properties of proton beams make it possible to deliver highdoses of radiation to the tumor with relative sparing of adjacent tissues. This form of therapy is effective for a wider range of uveal melanoma than any other modality, providing exceptionally-high rates of local tumor control. This is particularly the case with diffuse iris melanomas, many of which are unresectable. The chances of survival, ocular conservation, visual preservation and avoidance of iatrogenic morbidity depend greatly on the tumor size, location and extent. When treating any side-effects and/or complications, it is helpful to consider whether these are the result of collateral damage or persistence of the irradiated tumor ('toxic tumor syndrome').

Characterization of the HollandPTC proton therapy beamline dedicated to uveal melanoma treatment and an interinstitutional comparison

“…It has been estimated that 50 patients a year will be treated with the HollandPTC ocular beamline. 18 The clinical workflow [19][20][21][22][23][24] is similar to other existing institutions. Three to five tantalum clips surrounding the transilluminated Results: A pristine Bragg peak of HollandPTC eyeline corresponded to the constant energy of 75 MeV (maximal range 3.97 g/cm 2 in water) with an energy spread of 1.10 MeV.…”

“…It has been estimated that 50 patients a year will be treated with the HollandPTC ocular beamline 18 . The clinical workflow 19‐24 is similar to other existing institutions. Three to five tantalum clips surrounding the transilluminated tumor base are sewn onto the sclera during surgery 2 weeks before the PT treatment.…”

Three‐dimensional MRI‐based treatment planning approach for non‐invasive ocular proton therapy

“…The clinical workflow, including surgery for clips placement, in‐room simulations and positioning, planning and treatment completions, has been described in detail by a wide spectrum of publications over the last four decades 8,14–18 . In short, patients undergo surgery prior to proton therapy, with clips stitched onto the sclera to outline the tumor boundary.…”

“…3,13 The clinical workflow, including surgery for clips placement, in-room simulations and positioning, planning and treatment completions, has been described in detail by a wide spectrum of publications over the last four decades. 8,[14][15][16][17][18] In short, patients undergo surgery prior to proton therapy, with clips stitched onto the sclera to outline the tumor boundary. The purpose of these invasive clips is twofold: first, to delineate the tumor volume within a geometrical-based eye model; second, to position and verify the correct gazing angle during treatment.…”