In‐phantom dosimetry for the reaction as a source for accelerator‐based BNCT

Abstract

The use of the 13C(d,n) 14N reaction at Ed=1.5 MeV for accelerator-based boron neutron capture therapy (AB-BNCT) is investigated. Among the deuteron-induced reactions at low incident energy, the 3C(d,n)14N reaction turns out to be one of the best for AB-BNCT because of beneficial materials properties inherent to carbon and its relatively large neutron production cross section. The deuteron beam was produced by a tandem accelerator at MIT's Laboratory for Accelerator Beam Applications (LABA) and the neutron beam shaping assembly included a heavy water moderator and a lead reflector. The resulting neutron spectrum was dosimetrically evaluated at different depths inside a water-filled brain phantom using the dual ionization chamber technique for fast neutrons and photons and bare and cadmium-covered gold foils for the thermal neutron flux. The RBE doses in tumor and healthy tissue were calculated from experimental data assuming a tumor 10B concentration of 40 ppm and a healthy tissue 10B concentration of 11.4 ppm (corresponding to a reported ratio of 3.5:1). All results were simulated using the code MCNP, a general Monte Carlo radiation transport code capable of simulating electron, photon, and neutron transport. Experimental and simulated results are presented at 1, 2, 3, 4, 6, 8, and 10 cm depths along the brain phantom centerline. An advantage depth of 5.6 cm was obtained for a treatment time of 56 min assuming a 4 mA deuteron current and a maximum healthy tissue dose of 12.5 RBE Gy.

The possibility of an appropriate neutron beam achievement for medical purposes based on GEANT4 calculations

“…Moderators should be covered by the reflector to focus the beam. In this case, 20-cm-thick Pb is used as a reflector, which is known as one of the useful materials and widely used as an optimal one [16][17][18][19].…”

Boron neutron capture therapy design calculation of a 3H(p,n) reaction based BSA for brain cancer setup

“…Boron neutron capture therapy (BNCT) is a binary radiation therapy modality proposed as an alternative treatment for brain tumors. [1][2][3][4][5][6][7][8][9] The two major components of the therapy are a stable isotope 10 B of boron that can be concentrated preferentially in tumor cells and a beam of low energy neutrons. [2][3]8 Initially the BNCT treatment was proposed using the thermal neutrons beams.…”

“…2,8 There are several techniques to produce epithermal beams of neutrons either using nuclear reactors 1,6 or a particle accelerator as a neutron source. [2][3][4][5][7][8][9] Epithermal beams of neutrons from nuclear reactors have been tested to treat patients with a glioblastom multiforme, and intracranial metastatic and subcutaneous melanoma. 1,6 The accelerator based neutron sources have certain advantages over reactor based neutron sources such as low gamma ray background associated with neutrons, low cost, ease of placing an accelerator in or near hospitals etc.…”

Gadolinium concentration analysis in brain phantom by X-ray fluorescence

“…Also, boron has poor tumour to blood ratios, poor solubility in aqueous or biological media, and lacks tumour specificity [26][27][28][29][30][31][32][33][34][35][36][37][38] . In recent work, [39] the two radionuclides combined were considered for treatment.…”