1
|
Campos TPRD, Mendes BM, Trindade B, Araujo WL. Cardiac risk and MCNP/SISCODES doses in RT of the left internal mammary chain with photon and electron portals. Rep Pract Oncol Radiother 2018; 23:384-391. [DOI: 10.1016/j.rpor.2018.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/18/2017] [Accepted: 07/07/2018] [Indexed: 11/26/2022] Open
|
2
|
Mendes BM, Trindade BM, Fonseca TCF, de Campos TPR. Assessment of radiation-induced secondary cancer risk in the Brazilian population from left-sided breast-3D-CRT using MCNPX. Br J Radiol 2017; 90:20170187. [PMID: 28937271 PMCID: PMC6047661 DOI: 10.1259/bjr.20170187] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 09/06/2017] [Accepted: 09/08/2017] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE The aim of this work was to simulate a 6MV conventional breast 3D conformational radiation therapy (3D-CRT) with physical wedges (50 Gy/25#) in the left breast, calculate the mean absorbed dose in the body organs using robust models and computational tools and estimate the secondary cancer-incidence risk to the Brazilian population. METHODS The VW female phantom was used in the simulations. Planning target volume (PTV) was defined in the left breast. The 6MV parallel-opposed fields breast-radiotherapy (RT) protocol was simulated with MCNPx code. The absorbed doses were evaluated in all the organs. The secondary cancer-incidence risk induced by radiotherapy was calculated for different age groups according to the BEIR VII methodology. RESULTS RT quality indexes indicated that the protocol was properly simulated. Significant absorbed dose values in red bone marrow, RBM (0.8 Gy) and stomach (0.6 Gy) were observed. The contralateral breast presented the highest risk of incidence of a secondary cancer followed by leukaemia, lung and stomach. The risk of a secondary cancer-incidence by breast-RT, for the Brazilian population, ranged between 2.2-1.7% and 0.6-0.4%. CONCLUSION RBM and stomach, usually not considered as OAR, presented high second cancer incidence risks of 0.5-0.3% and 0.4-0.1%, respectively. This study may be helpful for breast-RT risk/benefit assessment. Advances in knowledge: MCNPX-dosimetry was able to provide the scatter radiation and dose for all body organs in conventional breast-RT. It was found a relevant risk up to 2.2% of induced-cancer from breast-RT, considering the whole thorax organs and Brazilian cancer-incidence.
Collapse
Affiliation(s)
| | - Bruno Machado Trindade
- Programa de Ciências e Técnicas Nucleares - Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Telma Cristina Ferreira Fonseca
- Programa de Ciências e Técnicas Nucleares - Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Tarcisio Passos Ribeiro de Campos
- Programa de Ciências e Técnicas Nucleares - Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| |
Collapse
|
3
|
Mendes BM, Almeida IGD, Trindade BM, Fonseca TCF, Campos TPRD. Development of a mouse computational model for MCNPx based on Digimouse (r) images and dosimetric assays. BRAZ J PHARM SCI 2017. [DOI: 10.1590/s2175-97902017000116092] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Bruno Melo Mendes
- Centro de Desenvolvimento da Tecnologia Nuclear, Brasil; Universidade Federal de Minas Gerais, Brazil
| | | | | | | | | |
Collapse
|
4
|
SOFT-RT: Software for IMRT simulations based on MCNPx code. Appl Radiat Isot 2016; 117:111-117. [DOI: 10.1016/j.apradiso.2015.12.061] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/21/2015] [Accepted: 12/29/2015] [Indexed: 11/23/2022]
|
5
|
de Lima CF, Campos TPR. Breastdosimetry of 99mTc-balloon in complementary radiotherapy. Appl Radiat Isot 2016; 118:117-123. [PMID: 27623043 DOI: 10.1016/j.apradiso.2016.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 08/02/2016] [Accepted: 08/02/2016] [Indexed: 11/20/2022]
Abstract
Dose reinforcement in primary tumor cavity can complement conventional radiotherapy in patients with early breast cancer. In this study, a dosimetric analysis was conducted by pertechnetate-99mTc-filled balloon brachytherapy (TBB). METHODS Dosimetry based on radiochromic films and on a computational voxel thorax model was performed. Calibration protocol achieved a mathematical relationship between dose and optical density in films placed on the surface at a distance of 0-9cm, 1cm between them, in which dose values were provided by MCNP® code. Moreover, experimental spatial dose distribution was prepared. A female thorax voxel model was developed in the SISCODES®/MCNP® codes. Additionally, experimental and computational doses at 8-10mm from balloon surface were compared. RESULTS Dose from 99mTc-balloon, with 16mm diameter, 32.22GBq activity, and 24h exposure time, achieved 8.08±0.42 (Ue) and 8.82±1.76 (Ue) Gy, at a distance of 10mm from the balloon surface for the experimental data and computational modeling, respectively, thus showing nonsignificant difference. The spatial dose distribution in the chest wall, glandular tissue, breast skin, and lung was presented. The dosimetric findings supported the TBB modality presenting a suitable spatial dose distribution in the tumor bed and preserving the adjacent health tissues. CONCLUSION TBB is a viable adjuvant brachytherapy modality for breast cancer in patients who have an appropriate indication.
Collapse
Affiliation(s)
- Carla Flávia de Lima
- Programa de Posgraduação em Ciências e Técnicas Nucleares, Departamento de Engenharia Nuclear da Escola de Engenharia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627 Bloco 4. S.2285, CEP 31270901 Belo Horizonte, MG, Brazil.
| | - Tarcísio P R Campos
- Programa de Posgraduação em Ciências e Técnicas Nucleares, Departamento de Engenharia Nuclear da Escola de Engenharia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627 Bloco 4. S.2285, CEP 31270901 Belo Horizonte, MG, Brazil.
| |
Collapse
|
6
|
de Campos TPR, Nogueira LB, Trindade B, Cuperschmid EM. Dosimetric intercomparison of permanent Ho-166 seed's implants and HDR Ir-192 brachytherapy in breast cancer. Rep Pract Oncol Radiother 2016; 21:240-9. [PMID: 27601957 PMCID: PMC5002017 DOI: 10.1016/j.rpor.2015.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 08/25/2015] [Accepted: 11/30/2015] [Indexed: 10/22/2022] Open
Abstract
AIM To provide a comparative dosimetric analysis of permanent implants of Ho(166)-seeds and temporary HDR Ir(192)-brachytherapy through computational simulation. BACKGROUND Brachytherapy with Ir(192)-HDR or LDR based on temporary wires or permanent radioactive seed implants can be used as dose reinforcement for breast radiation therapy. Permanent breast implants have not been a practical clinical routine; although, I(125) and Pd(103)-seeds have already been reported. Biodegradable Ho(166)-ceramic-seeds have been addressed recently. MATERIAL AND METHODS Simulations of implants of nine Ho(166)-seeds and equivalent with HDR Ir(192)-brachytherapy were elaborated in MCNP5, shaped in a computational multivoxel simulator which reproduced a female thorax phantom. Spatial dose rate distributions and dose-volume histograms were generated. Protocol's analysis involving exposure time, seed's activities and dose were performed. RESULTS Permanent Ho(166)-seed implants presented a maximum dose rate per unit of contained activity (MDR) of 1.1601 μGy h(-1) Bq(-1); and, a normalized MDR in standard points (8 mm, equidistant to 03-seeds - SP1, 10 mm - SP2) of 1.0% (SP1) and 0.5% (SP2), respectively. Ir(192)-brachytherapy presented MDR of 4.3945 × 10(-3) μGy h(-1) Bq(-1); and, 30% (SP1), and 20% (SP2). Therefore, seed's implant activities of 333 MBq (Ho(166)) and 259 GBq (Ir(192)) produced prescribed doses of 58 Gy (SP1; 5d) and 56 Gy (SP1, 5 fractions, 6 min), respectively. CONCLUSIONS Breast Ho(166)-implants of 37-111 MBq are attractive due to the high dose rate near 6-10 mm from seeds, equivalent to Ir(192)-brachytherapy of 259 GBq (3 fractions, 6 min) providing similar dose in standard points at a week; however, with spatial dose distribution better confined. The seed positioning can be adjusted for controlling the breast tumor, in stages I and II, in flat and deep tumors, without any breast volumetric limitation.
Collapse
Affiliation(s)
- Tarcisio Passos Ribeiro de Campos
- NRI – Nucleo de Radiações Ionizantes, Professor do Departamento de Engenharia Nuclear da Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Luciana Batista Nogueira
- Departamento de Anatomia e Imagem, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Bruno Trindade
- Programa de Ciências e Técnicas Nucleares, Núcleo de Radiações Ionizantes – NRI (Grupo de Pesquisa), UFMG, Brazil
| | | |
Collapse
|
7
|
Brandão SF, Campos TPR. Intracavitary moderator balloon combined with (252)Cf brachytherapy and boron neutron capture therapy, improving dosimetry in brain tumour and infiltrations. Br J Radiol 2015; 88:20140829. [PMID: 25927876 PMCID: PMC4628521 DOI: 10.1259/bjr.20140829] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 04/28/2015] [Accepted: 04/30/2015] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE This article proposes a combination of californium-252 ((252)Cf) brachytherapy, boron neutron capture therapy (BNCT) and an intracavitary moderator balloon catheter applied to brain tumour and infiltrations. METHODS Dosimetric evaluations were performed on three protocol set-ups: (252)Cf brachytherapy combined with BNCT (Cf-BNCT); Cf-BNCT with a balloon catheter filled with light water (LWB) and the same set-up with heavy water (HWB). RESULTS Cf-BNCT-HWB has presented dosimetric advantages to Cf-BNCT-LWB and Cf-BNCT in infiltrations at 2.0-5.0 cm from the balloon surface. However, Cf-BNCT-LWB has shown superior dosimetry up to 2.0 cm from the balloon surface. CONCLUSION Cf-BNCT-HWB and Cf-BNCT-LWB protocols provide a selective dose distribution for brain tumour and infiltrations, mainly further from the (252)Cf source, sparing the normal brain tissue. ADVANCES IN KNOWLEDGE Malignant brain tumours grow rapidly and often spread to adjacent brain tissues, leading to death. Improvements in brain radiation protocols have been continuously achieved; however, brain tumour recurrence is observed in most cases. Cf-BNCT-LWB and Cf-BNCT-HWB represent new modalities for selectively combating brain tumour infiltrations and metastasis.
Collapse
Affiliation(s)
- S F Brandão
- Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Escola de Engenharia, Belo Horizonte, Minas Gerais, Brazil
| | - T P R Campos
- Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Escola de Engenharia, Belo Horizonte, Minas Gerais, Brazil
| |
Collapse
|
8
|
Franca CADS, Vieira SL, Carvalho ACP, Bernabe AJS, Penna ABRC. Relationship between two year PSA nadir and biochemical recurrence in prostate cancer patients treated with iodine-125 brachytherap. Radiol Bras 2015; 47:89-93. [PMID: 25741055 PMCID: PMC4337165 DOI: 10.1590/s0100-39842014000200010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 10/22/2013] [Indexed: 11/22/2022] Open
Abstract
Objective To evaluate the relationship between two year PSA nadir (PSAn) after brachytherapy
and biochemical recurrence rates in prostate cancer patients. Materials and Methods In the period from January 1998 to August 2007, 120 patients were treated with
iodine-125 brachytherapy alone. The results analysis was based on the definition
of biochemical recurrence according to the Phoenix Consensus. Results Biochemical control was observed in 86 patients (71.7%), and biochemical
recurrence, in 34 (28.3%). Mean PSAn was 0.53 ng/ml. The mean follow-up was 98
months. The patients were divided into two groups: group 1, with two year PSAn
< 0.5 ng/ml after brachytherapy (74 patients; 61.7%), and group 2, with two
year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%). Group 1
presented biochemical recurrence in 15 patients (20.3%), and group 2, in 19
patients (43.2%) (p < 0.02). The analysis of biochemical
disease-free survival at seven years, stratified by the two groups, showed values
of 80% and 64% (p < 0.02), respectively. Conclusion Levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly
correlated with a poor prognosis. This fact may help to identify patients at risk
for disease recurrence.
Collapse
Affiliation(s)
- Carlos Antônio da Silva Franca
- Master, MD, Radiation Oncology at Instituto Brasileiro de Oncologia (IBO), Radioterapia Botafogo, Universidade Federal do Rio de Janeiro (UFRJ) and Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio), Rio de Janeiro, RJ, Brazil
| | - Sérgio Lannes Vieira
- Full Professor, MD, Radiation Oncology at Instituto Brasileiro de Oncologia (IBO), Radioterapia Botafogo and Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio), Rio de Janeiro, RJ, Brazil
| | | | | | - Antonio Belmiro Rodrigues Campbell Penna
- PhD, MD, Radiation Oncology at Instituto Brasileiro de Oncologia (IBO), Radioterapia Botafogo and Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio), Rio de Janeiro, RJ, Brazil
| |
Collapse
|
9
|
Brandão SDF, Campos TPRD. Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors. Radiol Bras 2013. [DOI: 10.1590/s0100-39842013000400008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Objective Comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and Methods Simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results Intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h-1.p-1.s, respectively, on the healthy tissue, on the balloon periphery and on the I 1 and I 2 tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h-1.p-1.s, respectively on the healthy tissue, on the target tumor and on the I 1 and I 2 infiltration zones. Conclusion Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones.
Collapse
|
10
|
Trindade BM, Christóvão MT, Trindade DDFM, Falcão PL, Campos TPRD. Dosimetria comparativa de braquiterapia de próstata com sementes de I-125 e Pd-103 via SISCODES/MCNP. Radiol Bras 2012. [DOI: 10.1590/s0100-39842012000500007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJETIVO: O presente artigo visa apresentar um estudo dosimétrico comparativo de braquiterapia de próstata com sementes de I-125 e Pd-103. MATERIAIS E MÉTODOS: Um protocolo adotado para ambos os implantes com 148 sementes foi simulado em um fantoma tridimensional heterogêneo de pelve por meio dos códigos SISCODES/MCNP5. Histogramas dose-volume na próstata, bexiga e reto, índices de doses D10, D30, D90, D0,5cc, D2cc e D7cc, e representações de distribuição espacial de dose foram avaliados. RESULTADOS: A atividade inicial de cada semente de I-125, para que D90 seja equivalente à dose de prescrição, foi calculada em 0,42 mCi, e de Pd-103, em 0,94 mCi. A dose máxima na uretra foi 90% e 108% da dose de prescrição para I-125 e Pd-103, respectivamente. A D2cc para I-125 foi 30 Gy no reto e 127 Gy na bexiga, e para Pd-103 foi 29 Gy no reto e 189 Gy na bexiga. A D10 no osso do púbis foi 144 Gy para I-125 e 66 Gy para Pd-103. CONCLUSÃO: Os resultados indicam que os implantes de Pd-103 e I-125 puderam depositar a dose prescrita no volume alvo. Entre os achados, observou-se excessiva exposição de radiação nos ossos da pelve, principalmente no protocolo com I-125.
Collapse
|
11
|
Christóvão MT, Campos TPRD, Trindade BM. Simulação e análise dosimétrica de protonterapia e íons de carbono no tratamento do melanoma uveal. Radiol Bras 2011. [DOI: 10.1590/s0100-39842011000600008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
OBJETIVO: Este artigo apresenta a avaliação dosimétrica da radioterapia por íons de carbono em comparação à protonterapia. MATERIAIS E MÉTODOS: As simulações computacionais foram elaboradas no código Geant4 (GEometry ANd Tracking). Um modelo de olho discretizado em voxels implementado no sistema Siscodes (sistema computacional para dosimetria em radioterapia) foi empregado, em que perfis de dose em profundidade e curvas de isodose foram gerados e superpostos. Nas simulações com feixe de íons de carbono, distintos valores de energia do feixe foram adotados, enquanto nas simulações com feixe de prótons os dispositivos da linha de irradiação foram incluídos e diferentes espessuras do material absorvedor foram aplicadas. RESULTADOS: As saídas das simulações foram processadas e integradas ao Siscodes para gerar as distribuições espaciais de dose no modelo ocular, considerando alterações do posicionamento de entrada do feixe. Os percentuais de dose foram normalizados em função da dose máxima para um feixe em posição de entrada específica, energia da partícula incidente e número de íons de carbono e de prótons incidentes. CONCLUSÃO: Os benefícios descritos e os resultados apresentados contribuem para o desenvolvimento das aplicações clínicas e das pesquisas em radioterapia ocular por íons de carbono e prótons.
Collapse
|