title: Estimation of neutron-equivalent dose in organs of patients undergoing radiotherapy by the use of a novel online digital detector.
abstract: Neutron peripheral contamination in patients undergoing high-energy photon radiotherapy is considered as a risk factor for secondary cancer induction. Organ-specific neutron-equivalent dose estimation is therefore essential for a reasonable assessment of these associated risks. This work aimed to develop a method to estimate neutron-equivalent doses in multiple organs of radiotherapy patients. The method involved the convolution, at 16 reference points in an anthropomorphic phantom, of the normalized Monte Carlo neutron fluence energy spectra with the kerma and energy-dependent radiation weighting factor. This was then scaled with the total neutron fluence measured with passive detectors, at the same reference points, in order to obtain the equivalent doses in organs. The latter were correlated with the readings of a neutron digital detector located inside the treatment room during phantom irradiation. This digital detector, designed and developed by our group, integrates the thermal neutron fluence. The correlation model, applied to the digital detector readings during patient irradiation, enables the online estimation of neutron-equivalent doses in organs. The model takes into account the specific irradiation site, the field parameters (energy, field size, angle incidence, etc) and the installation (linac and bunker geometry). This method, which is suitable for routine clinical use, will help to systematically generate the dosimetric data essential for the improvement of current risk-estimation models.
authors.affiliation: Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Sánchez-Doblado
authors.forename: C
authors.initials: C
authors.lastname: Domingo
authors.forename: F
authors.initials: F
authors.lastname: Gómez
authors.forename: B
authors.initials: B
authors.lastname: Sánchez-Nieto
authors.forename: J L
authors.initials: JL
authors.lastname: Muñiz
authors.forename: M J
authors.initials: MJ
authors.lastname: García-Fusté
authors.forename: M R
authors.initials: MR
authors.lastname: Expósito
authors.forename: R
authors.initials: R
authors.lastname: Barquero
authors.forename: G
authors.initials: G
authors.lastname: Hartmann
authors.forename: J A
authors.initials: JA
authors.lastname: Terrón
authors.forename: J
authors.initials: J
authors.lastname: Pena
authors.forename: R
authors.initials: R
authors.lastname: Méndez
authors.forename: F
authors.initials: F
authors.lastname: Gutiérrez
authors.forename: F X
authors.initials: FX
authors.lastname: Guerre
authors.forename: J
authors.initials: J
authors.lastname: Roselló
authors.forename: L
authors.initials: L
authors.lastname: Núñez
authors.forename: L
authors.initials: L
authors.lastname: Brualla-González
authors.forename: F
authors.initials: F
authors.lastname: Manchado
authors.forename: A
authors.initials: A
authors.lastname: Lorente
authors.forename: E
authors.initials: E
authors.lastname: Gallego
authors.forename: R
authors.initials: R
authors.lastname: Capote
authors.forename: D
authors.initials: D
authors.lastname: Planes
authors.forename: J I
authors.initials: JI
authors.lastname: Lagares
authors.forename: X
authors.initials: X
authors.lastname: González-Soto
authors.forename: F
authors.initials: F
authors.lastname: Sansaloni
authors.forename: R
authors.initials: R
authors.lastname: Colmenares
authors.forename: K
authors.initials: K
authors.lastname: Amgarou
authors.forename: E
authors.initials: E
authors.lastname: Morales
authors.forename: R
authors.initials: R
authors.lastname: Bedogni
authors.forename: J P
authors.initials: JP
authors.lastname: Cano
authors.forename: F
authors.initials: F
authors.lastname: Fernández
mesh_terms: D000054:Acceleration; D006801:Humans; D009010:Monte Carlo Method; D009502:Neutrons / Q000009:adverse effects*; D009862:Online Systems; D058958:Organs at Risk / Q000528:radiation effects*; D019047:Phantoms, Imaging; D061766:Proton Therapy / Q000009:adverse effects / Q000295:instrumentation; D011829:Radiation Dosage; D011879:Radiotherapy Dosage; D011881:Radiotherapy, Computer-Assisted / Q000009:adverse effects* / Q000295:instrumentation*