Spatial fractionation of the dose using neon and heavier ions: A Monte Carlo study

摘要: Purpose: This work explores a new radiation therapy approach which might trigger renewed use of neon and heavier ions to treat cancers. These were shown be extremely efficient in radioresistant tumor killing. Unfortunately, the region also extends into normal tissue front tumor. The strategy authors propose is profit from well-established sparing effect thin spatially fractionated beams, so that impact on tissues minimized while high control achieved. main goal this provide proof concept approach. With aim, dosimetric study was carried out as first step evaluate interest further explorations avenue. Methods: GATE/GEANT4 v.6.1 Monte Carlo simulation platform employed simulate arrays rectangular minibeams (700 μm × 2 cm) four (Ne, Si, Ar, Fe). irradiations performed with cm-long spread-out Bragg peak centered at 7 cm-depth. Dose distributions water phantom scored considering two center-to-center distances: 1400 3500 μm. Peak valley doses, peak-to-valley dose ratios (PVDRs), beam penumbras, relative contribution ofmore » nuclear fragments electromagnetic processes assessed figures merit. In addition, type proportion secondary evaluated both regions. Results: Extremely PVDR values (>100) low doses obtained. higher atomic number (Z) primary ion is, lower valleys narrower penumbras. Although yield products increases Z, actual being deposited by starts dominant deeper points, helping proximal tissues. Additionally, wider distance leads valleys. Conclusions: computed suggest spatial fractionation combined submillimetric field sizes allow profiting efficiency for treatment tumors, preserving authors’ results support exploration Next steps include realization biological experiment confirm shifting complication probability curves.« less