1Department of Physics, Tilak Dhari P. G. College, Jaunpur, (U.P.) - 222002, India
2V.B.S. Purvanchal University, Jaunpur, (U.P.) - 222003, India
3Department of Radiation Oncology, Uttar Pradesh University of Medical Sciences, Saifai, Etawah (U.P.) - 206130, India
4Department of Physics, D.A.V. Degree College, Lucknow, (U.P.) - 226004, India
5Department of Radiotherapy, King George Medical University, Lucknow (U.P.) - 226003, India
6Department of Radiation Oncology, Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow (U.P.) 226010, India
چکیده
Background: In Radiotherapy, computation of dose is important since in a small field with heterogeneity, dose is usually computed with discrepancies. Objective: The present study was aimed to evaluate the dosimetry of treatment planning algorithms in lung equivalent heterogeneous medium for Volumetric Modulated Arc Therapy (VMAT) with step and shoot Intensity-Modulated Radiation Therapy (ss-IMRT), and dynamic Intensity-Modulated Radiation Therapy (d-IMRT). Material and Methods: In this experimental study, Computerized Imaging Reference System (CIRS) phantom was used with an inhomogeneous Racemosa wood cylinder for two types of tumors, namely, Left Lung Central Tumor (LCT) and Left Lung Peripheral Tumor (LPT) in the CIRS left lung cavity. The computed tomography (CT) datasets were employed with the generation of VMAT, d-IMRT and ss-IMRT plans for the LCT and LPT irradiated with 6 MV photon beams. In this study, the accuracy and efficacy of two algorithms: Monte Carlo (MC) and the Pencil Beam (PB), from the Monaco treatment planning system (TPS), were tested by using Gafchromic EBT3 films and CIRS thorax phantom. Results: Regardless of treatment techniques, both algorithms exhibited higher divergence in LPT than LCT. In both LCT and LPT, the highest deviation was near the tumor-lung junction. However, the deviation was higher in the PB algorithm than MC algorithm, with a minimally acceptable variation of -0.8%. Conclusion: The MC algorithm shows more consistency for EBT3 measured dose in lung equivalent heterogeneous medium. However, accurate dose predictions are complicated due to electronic disequilibrium within and at the interface of inhomogeneity. These constraints may cause variations from the anticipated outcomes of the treatments.
Mesbahi A. The effect of electronic disequilibrium on the received dose by lung in small fields with photon beams: Measurements and Monte Carlo study. Iran J Radiat Res. 2008;6:70‑6.
Verma T, Painuly NK, Mishra SP, Shajahan M, Singh N, Bhatt ML, et al. Performance Evaluation of Algorithms in Lung IMRT: A comparison of Monte Carlo, Pencil Beam, Superposition, Fast Superposition and Convolution Algorithms. J Biomed Phys Eng. 2016;6(3):127-38. PubMed PMID: 27853720. PubMed PMCID: PMC5106545.
Young ME, Kornelsen RO. Dose corrections for low-density tissue inhomogeneities and air channels for 10-MV x rays. Med Phys. 1983;10(4):450-5. doi: 10.1118/1.595392. PubMed PMID: 6888356.
Klein EE, Morrison A, Purdy JA, Graham MV, Matthews J. A volumetric study of measurements and calculations of lung density corrections for 6 and 18 MV photons. Int J Radiat Oncol Biol Phys. 1997;37(5):1163-70. doi: 10.1016/s0360-3016(97)00110-7. PMID: 9169827.
Wambersie A. The role of the ICRU in quality assurance in radiation therapy. Int J Radiat Oncol Biol Phys. 1984;10(Suppl 1):81-6. doi: 10.1016/0360-3016(84)90454-1. PubMed PMID: 6429103.
Golestani A, Houshyari M, Mostaar A, Jabbari Arfaie A. Evaluation of Dose Calculation Algorithms of Isogray Treatment Planning System Using Measurement in Heterogeneous Phantom. Rep Radiother Oncol. 2015;2(3):e5320. doi: 10.17795/rro-5320.
Verma TR, Painuly NK, Mishra SP, Singh N, Bhatt MLB, Jamal N, Pant MC. Evaluation of dose calculation accuracy of various algorithms in lung equivalent inhomogeneity: Comparison of calculated data with Gafchromic film measured results. J Cancer Res Ther. 2017;13(6):1007-14. doi: 10.4103/0973-1482.168992. PubMed PMID: 29237967.
Nalbant N, Kesen D, Hatice B. Pre-treatment dose verification of IMRT using gafchromic EBT3 film and 2D array. J Nucl Med Radiat Ther. 2014;5(2):1-6. doi: 10.4172/2155-9619.1000182.
Casanova Borca V, Pasquino M, Russo G, Grosso P, Cante D, Sciacero P, et al. Dosimetric characterization and use of GAFCHROMIC EBT3 film for IMRT dose verification. J Appl Clin Med Phys. 2013;14(2):4111. doi: 10.1120/jacmp.v14i2.4111. PubMed PMID: 23470940. PubMed PMCID: PMC5714357.
Wen N, Lu S, Kim J, Qin Y, Huang Y, Zhao B, Liu C, Chetty IJ. Precise film dosimetry for stereotactic radiosurgery and stereotactic body radiotherapy quality assurance using Gafchromic™ EBT3 films. Radiat Oncol. 2016;11(1):132. doi: 10.1186/s13014-016-0709-4. PubMed PMID: 27716323. PubMed PMCID: PMC5050597.
Tillikainen L, Helminen H, Torsti T, Siljamäki S, Alakuijala J, Pyyry J, Ulmer W. A 3D pencil-beam-based superposition algorithm for photon dose calculation in heterogeneous media. Phys Med Biol. 2008;53(14):3821-39. doi: 10.1088/0031-9155/53/14/008. PubMed PMID: 18583728.
Gagné IM, Zavgorodni S. Evaluation of the analytical anisotropic algorithm in an extreme water-lung interface phantom using Monte Carlo dose calculations. J Appl Clin Med Phys. 2006;8(1):33-46. doi: 10.1120/jacmp.v8i1.2324. PubMed PMID: 17592451. PubMed PMCID: PMC5722400.
Bragg CM, Conway J. Dosimetric verification of the anisotropic analytical algorithm for radiotherapy treatment planning. Radiother Oncol. 2006;81(3):315-23. doi: 10.1016/j.radonc.2006.10.020. PubMed PMID: 17125862.
Stathakis S, Esquivel C, Quino LV, Myers P, Calvo O, Mavroidis P, et al. Accuracy of the small field dosimetry using the Acuros XB dose calculation algorithm within and beyond heterogeneous media for 6 MV photon beams. Int J Med Phys Clin Radiat Oncol. 2012;1:78‑87. doi: 10.4236/ijmpcero.2012.13011.
Ojala JJ, Kapanen MK, Hyödynmaa SJ, Wigren TK, Pitkänen MA. Performance of dose calculation algorithms from three generations in lung SBRT: comparison with full Monte Carlo-based dose distributions. J Appl Clin Med Phys. 2014;15(2):4662. doi: 10.1120/jacmp.v15i2.4662. PubMed PMID: 24710454. PubMed PMCID: PMC5875463.
Alagar AGB, Ganesh KM, Kaviarasu K. Dose Calculation Accuracy of AAA and AcurosXB Algorithms for Small Central and Interface Lung Lesions - Verification with Gafchromic Film Dosimetry. Asian Pac J Cancer Prev. 2018;19(1):253-9. doi: 10.22034/APJCP.2018.19.1.253. PubMed PMID: 29374410. PubMed PMCID: PMC5844627.
Saini A, Pandey VP, Singh A, Kumar P. Evaluating impact of medium variation on dose calculated through planning system in a low cost in-house phantom. Biomed Phys Eng Express. 2022;8(2):025022. doi: 10.1088/2057-1976/ac53bc. PubMed PMID: 35144251.