Abstract Stereotactic radiotherapy (SRT), also known as stereotactic ablative radiotherapy (SABR), includes stereotactic radiosurgery and stereotactic body radiotherapy (SBRT). This technique has the characteristics of large single fractional dose, few fractions, high equivalent biological doses, and rapid fall off-target doses. It can be implemented by relatively special equipment such as Gamma knife, Cyberknife, Tomotherapy and Vero 4D RT system, etc. In many cases, SBRT technique is employed based on linear accelerators. SRT differs from conventional radiotherapy in terms of the plan design and plan evaluation. Consequently, it is necessary to discuss the differences and provide guidance for clinical application and research.
Wang Xuetao,Wang Xin,Bai Sen et al. Physics issues on plan design and evaluation for stereotactic radiotherapy based on linear accelerator[J]. Chinese Journal of Radiation Oncology, 2021, 30(3): 221-229.
Wang Xuetao,Wang Xin,Bai Sen et al. Physics issues on plan design and evaluation for stereotactic radiotherapy based on linear accelerator[J]. Chinese Journal of Radiation Oncology, 2021, 30(3): 221-229.
[1] Alayed Y,Cheung P,Vesprini D,et al.SABR in high-risk prostate cancer:outcomes from 2 prospective clinical trials with and without elective nodal irradiation[J].Int J Radiat Oncol Biol Phys,2019,104(1):36-41.DOI:10.1016/j.ijrobp.2018.11.011. [2] Brunner TB,Blanck O,Lewitzki V,et al.Stereotactic body radiotherapy dose and its impact on local control and overall survival of patients for locally advanced intrahepatic and extrahepatic cholangiocarcinoma[J].Radiother Oncol,2019,132(1):42-47.DOI:10.1016/j.radonc.2018.11.015. [3] Klement RJ,Abbasi-Senger N,Adebahr S,et al.The impact of local control on overall survival after stereotactic body radiotherapy for liver and lung metastases from colorectal cancer:a combined analysis of 388 patients with 500 metastases[J].BMC Cancer,2019,19(1):173.DOI:10.1186/s12885-019-5362-5. [4] Bezjak A,Paulus R,Gaspar LE,et al.Safety and efficacy of a five-fraction stereotactic body radiotherapy schedule for centrally located non-small-cell lung cancer:NRG oncology/RTOG 0813 trial[J].J Clin Oncol,2019,37(15):1316-1325.DOI:10.1200/JCO.18.00622. [5] Rauschenbach BM,Mackowiak L,Malhotra HK.A dosimetric comparison of three-dimensional conformal radiotherapy,volumetric-modulated arc therapy,and dynamic conformal arc therapy in the treatment of non-small cell lung cancer using stereotactic body radiotherapy[J].J Appl Clin Med Phys,2014,15(5):4898.DOI:10.1120/jacmp.v15i5.4898. [6] Peterlin P,Stani?B K,Méndez I,et al.Treating lung cancer with dynamic conformal arc therapy:a dosimetric study[J].Radiat Oncol,2017,12(1):93.DOI:10.1186/s13014-017-0823-y. [7] Stathakis S,Narayanasamy G,Licon A,et al.A dosimetric comparison between volumetric-modulated arc therapy and dynamic conformal arc therapy in SBRT[J].J BUON,2019,24(2):838-843. [8] Mix M,Tanny S,Nsouli T,et al.Outcomes following stereotactic body radiotherapy with intensity-modulated therapy versus three-dimensional conformal radiotherapy in early stage non-small cell lung cancer[J].Lung Cancer,2019,10:151-159.DOI:10.2147/LCTT.S235713. [9] Badellino S,Muzio JD,Schivazappa G,et al.No differences in radiological changes after 3D conformal vs. VMAT-based stereotactic radiotherapy for early stage non-small cell lung cancer[J].Br J Radiol,2017,90(1078):20170143.DOI:10.1259/bjr.20170143. [10] Sapkaroski D,Osborne C,Knight KA.A review of stereotactic body radiotherapy-is volumetric modulated arc therapy the answer?[J].J Med Radiat Sci,2015,62(2):142-151.DOI:10.1002/jmrs.108. [11] Morales-Paliza MA,Coffey CW,Ding GX.Evaluation of the dynamic conformal arc therapy in comparison to intensity-modulated radiation therapy in prostate,brain,head-and-neck and spine tumors[J].J Appl Clin Med Phys,2010,12(2):3197.DOI:10.1120/jacmp.v12i2.3197. [12] Al-Fishawy MM,Amin AE,Sallam AM,et al.Comparison of patient setup error effect on target evaluation parameters in 3D-CRT,IMRT and VMAT for gioblastoma[J].Pan Arab J Oncol,2018,Suppl 2(11):64-71. [13] Edvardsson A,Nordström F,Ceberg C,et al.Motion induced interplay effects for VMAT radiotherapy[J].Phys Med Biol,2018,63(8):085012.DOI:10.1088/1361-6560/aab957. [14] Stambaugh C,Nelms BE,Dilling T,et al.Experimentally studied dynamic dose interplay does not meaningfully affect target dose in VMAT SBRT lung treatments[J].Med Phys,2013,40(9):91710.DOI:10.1118/1.4818255. [15] Ong CL,Dahele M,Slotman BJ,et al.Dosimetric impact of the interplay effect during stereotactic lung radiation therapy delivery using flattening filter-free beams and volumetric modulated arc therapy[J].Int J Radiat Oncol Biol Phys,2013,86(4):743-748.DOI:10.1016/j.ijrobp.2013.03.038. [16] Dong P,Yu V,Nguyen D,et al.Feasibility of using intermediate X-ray energies for highly conformal extracranial radiotherapy[J].Med Phys,2014,41(4):041709.DOI:10.1118/1.4868464. [17] Zhang Y,Feng Y,Ahmad M,et al.Intermediate megavoltage photon beams for improved lung cancer treatments[J].PLoS One,2015,10(12):e0145117.DOI:10.1371/journal.pone.0145117. [18] Pasler M,Georg D,Wirtz H,et al.Effect of photon-beam energy on VMAT and IMRT treatment plan quality and dosimetric accuracy for advanced prostate cancer[J].Strahlenther Onkol,2011,187(12):792-798.DOI:10.1007/s00066-011-1150-0. [19] Kleiner H,Podgorsak MB.The dosimetric significance of using 10MV photons for volumetric modulated arc therapy for post-prostatectomy irradiation of the prostate bed[J].Radiol Oncol,2016,50(2):232-237.DOI:10.1515/raon-2016-0012. [20] NCRP. Report No.79:neutron contamination from medical electron accelerators[R].Bethesda,Maryland:NCRP,1987. [21] Tambe NS,Fryer A,Marsden JE,et al.Determination of clinically appropriate flattening filter free (FFF) energy for treating lung SABR using treatment plans and delivery measurements[J].Biomed Phys Express,2016,2(6):065016.DOI:10.1088/2057-1976/2/6/065016. [22] Pokhrel D,Halfman M,Sanford L.FFF-VMAT for SBRT of lung lesions:improves dose coverage at tumor-lung interface compared to flattened beams[J].J Appl Clin Med Phys,2020,21(1):26-35.DOI:10.1002/acm2.12764. [23] Guckenberger M,Roesch J,Baier K,et al.Dosimetric consequences of translational and rotational errors in frame-less image-guided radiosurgery[J].Radiat Oncol,2012,7(1):63.DOI:10.1186/1748-717X-7-63. [24] Seuntjens J,Lartigau EF,Cora S,et al.ICRU report 91.Prescribing,recording,and reporting of stereotactic treatments with small photon beams[J].ICRU,2014,2(14):1-160. [25] Wang W,Chen D,Han C,et al.Partial and full arc volumetric modulated arc therapy in lung cancer stereotactic body radiotherapy with different definitions of internal target volume based on 4D CT[J].Int J Med Phys Clin Engineer Radiat Oncol,2018,7:491-502.DOI:10.4236/ijmpcero.2018.74042. [26] Lim DH,Yi BY,Mirmiran A,et al.Optimal beam arrangement for stereotactic body radiation therapy delivery in lung tumors[J].Acta Oncol,2010,49(2):219-224.DOI:10.3109/02841860903302897. [27] Fitzgerald R,Owen R,Barry T,et al.The effect of beam arrangements and the impact of non-coplanar beams on the treatment planning of stereotactic ablative radiation therapy for early stage lung cancer[J].J Med Radiat Sci,2016,63(1):31-40.DOI:10.1002/jmrs.118. [28] Woods K,Nguyen D,Tran A,et al.Viability of non-coplanar VMAT for liver SBRT as compared to coplanar VMAT and beam orientation optimized 4π IMRT[J].Adv Radiat Oncol,2016,1(1):67-75.DOI:10.1016/j.adro.2015.12.004. [29] IshⅡ K,Okada W,Ogino R,et al.A treatment-planning comparison of three beam arrangement strategies for stereotactic body radiation therapy for centrally located lung tumors using volumetric-modulated arc therapy[J].J Radiat Res,2016,57(3):273-279.DOI:10.1093/jrr/rrv105. [30] De Ruysscher D,Faivre-Finn C,Moeller D,et al.European organization for research and treatment of cancer (EORTC) recommendations for planning and delivery of high-dose,high precision radiotherapy for lung cancer[J].Radiother Oncol,2017,124(1):1-10.DOI:10.1016/j.radonc.2017.06.003. [31] Clark GM,Popple RA,Young PE,et al.Feasibility of single-isocenter volumetric modulated arc radiosurgery for treatment of multiple brain metastases[J].Int J Radiat Oncol Biol Phys,2010,76(1):296-302.DOI:10.1016/j.ijrobp.2009.05.029. [32] Thomas EM,Popple RA,Covington E,et al.Single-isocenter,multiple metastasis treatment planning[M].Radiotherapy in managing brain metastases,2020,249-280.DOI:10.1007/978-3-030-43740-4. [33] Thomas EM,Popple RA,Wu X,et al.Comparison of plan quality and delivery time between volumetric arc therapy (RapidArc) and gamma knife radiosurgery for multiple cranial metastases[J].Neurosurgery,2014,75(4):409-418.DOI:10.1227/NEU.0000000000000448. [34] Roper J,Chanyavanich V,Betzel GT,et al.Single-isocenter multiple-target stereotactic radiosurgery:risk of compromised coverage[J].Int J Radiat Oncol Biol Phys,2015,93(3):540-546.DOI:10.1016/j.ijrobp.2015.07.2262. [35] Chang J,Wernicke AG,Pannullo SC.Restricted single isocenter for multiple targets dynamic conformal arc (RSIMT DCA) technique for brain stereotactic radiosurgery (SRS) planning[J].J Radiosurg SBRT,2018,5(2):145-156. [36] Kirkpatrick JP,Wang Z,Sampson JH,et al.Defining the optimal planning target volume in image-guided stereotactic radiosurgery of brain metastases:results of a randomized trial[J].Int J Radiat Oncol Biol Phys,2015,91(1):100-108.DOI:10.1016/j.ijrobp.2014.09.004. [37] Gevaert T,Verellen D,Engels B,et al.Clinical evaluation of a robotic 6-degree of freedom treatment couch for frameless radiosurgery[J].Int J Radiat Oncol Biol Phys,2012,83(1):467-474.DOI:10.1016/j.ijrobp.2011.05.048. [38] Alderliesten T,Sonke JJ,Betgen A,et al.3D surface imaging for monitoring intrafraction motion in frameless stereotactic body radiotherapy of lung cancer[J].Radiother Oncol,2012,105(2):155-160.DOI:10.1016/j.radonc.2012.08.016. [39] Ding GX,Duggan DM,Lu B,et al.Impact of inhomogeneity corrections on dose coverage in the treatment of lung cancer using stereotactic body radiation therapy[J].Med Phys,2007,34(7):2985-2994.DOI:10.1118/1.2745923. [40] Papanikolaou N,Battista J,Boyer A,et al.Tissue inhomogeneity corrections for megavoltage photon beams.AAPM Report No.85[EB/OL] [2020-02-10].https://www.aapm.org/pubs/reports/rpt_85.pdf. [41] Bush K,Gagne IM,Zavgorodni S,et al.Dosimetric validation of Acuros XB with Monte Carlo methods for photon dose calculations[J].Med Phys,2011,38(4):2208-2221.DOI:10.1118/1.3567146. [42] Chopra KL,Leo P,Kabat C,et al.Evaluation of dose calculation accuracy of treatment planning systems in the presence of tissue heterogeneities[J].Ther Radiol Oncol,2018,2(1):28.DOI:10.21037/tro.2018.07.01. [43] Dempsey JF,Romeijn HE,Li JG,et al.A fourier analysis of the dose grid resolution required for accurate IMRT fluence map optimization[J].Med Phys,2005,32(2):380-388.DOI:10.1118/1.1843354. [44] Bedford JL,Childs PJ,Nordmark-Hansen V,et al.Commissioning and quality assurance of the Pinnacle (3) radiotherapy treatment planning system for external beam photons[J].Br J Radiol,2003,76(903):163-176.DOI:10.1259/bjr/42085182. [45] Benedict SH,Yenice KM,Followill D,et al.Stereotactic body radiation therapy:the report of AAPM task group 101[J].Med Phys,2010,37(8):4078-4101.DOI:10.1118/1.3438081. [46] Ma CC.Physics and dosimetric principles of SRS and SBRT[J].Mathews J Cancer Sci,2019,4(2):22.DOI:10.30654/MJCS.10022. [47] Consortium U.Stereotactic ablative body radiatin therapy (SABR):a resource[EB/OL] [2020-02-10].https://www.sabr.org.uk/wp-content/uploads/2019/04/SABRconsortium-guidelines-2019-v6.1.0.pdf. [48] Ding M,Newman F,Chen C,et al.Dosimetric comparison between 3DCRT and IMRT using different multileaf collimators in the treatment of brain tumors[J].Med Dosim,2009,34(1):1-8.DOI:10.1016/j.meddos.2007.04.001. [49] Shang Q,Qi P,Ferjani S,et al.Effect of MLC leaf width on treatment adaptation and accuracy for concurrent irradiation of prostate and pelvic lymph nodes[J].Med Phys,2013,40(6):061701.DOI:10.1118/1.4803499. [50] Amoush A,Long H,Subedi L,et al.Dosimetric effect of multileaf collimator leaf width on volumetric modulated arc stereotactic radiotherapy for spine tumors[J].Med Dosim,2017,42(2):111-115.DOI:10.1016/j.meddos.2017.01.007. [51] Subramanian SV,Subramani V,Thirumalai-Swamy S,et al.Is 5mm MMLC suitable for VMAT-based lung SBRT? A dosimetric comparison with 2.5mm HDMLC using RTOG-0813 treatment planning criteria for both conventional and high-dose flattening filter-free photon beams[J].J Appl Clin Med Phys,2015,16(4):112-124.DOI:10.1120/jacmp.v16i4.5415. [52] Abisheva Z,Floyd SR,Salama JK,et al.The effect of MLC leaf width in single-isocenter multi-target radiosurgery with volumetric modulated arc therapy[J].J Radiosurg SBRT,2019,6(2):131-138. [53] Serna A,Puchades V,Mata F,et al.Influence of multi-leaf collimator leaf width in radiosurgery via volumetric modulated arc therapy and 3D dynamic conformal arc therapy[J].Phys Med,2015,31(3):293-296.DOI:10.1016/j.ejmp.2015.01.011. [54] Feuvret L,No?Bl G,Mazeron JJ,et al.Conformity index:a review[J].Int J Radiat Oncol Biol Phys,2006,64(2):333-342.DOI:10.1016/j.ijrobp.2005.09.028. [55] Yaparpalvi R,Garg MK,Shen J,et al.Evaluating which plan quality metrics are appropriate for use in lung SBRT[J].Br J Radiol,2018,91(1083):20170393.DOI:10.1259/bjr.20170393. [56] Paddick I.A simple scoring ratio to index the conformity of radiosurgical treatment plans.Technical note[J].J Neurosurg,2000,93(Suppl 3):219-222.DOI:10.3171/jns.2000.93.supplement. [57] Craft D,Khan F,Young M,et al.The price of target dose uniformity[J].Int J Radiat Oncol Biol Phys,2016,96(4):913-914.DOI:10.1016/j.ijrobp.2016.07.033. [58] Lucia F,Key S,Dissaux G,et al.Inhomogeneous tumor dose distribution provides better local control than homogeneous distribution in stereotactic radiotherapy for brain metastases[J].Radiother Oncol,2019,130:132-138.DOI:10.1016/j.radonc.2018.06.039. [59] Abraham C,Garsa A,Badiyan SN,et al.Internal dose escalation is associated with increased local control for non-small cell lung cancer (NSCLC) brain metastases treated with stereotactic radiosurgery (SRS)[J].Adv Radiat Oncol,2018,3(2):146-153.DOI:10.1016/j.adro.2017.11.003. [60] Timmerman RD.An overview of hypofractionation and introduction to this issue of seminars in radiation oncology[J].Semin Radiat Oncol,2008,18(4):215-222.DOI:10.1016/j.semradonc.2008.04.001. [61] Hanna GG,Murray L,Patel R,et al.UK consensus on normal tissue dose constraints for stereotactic radiotherapy[J].Clin Oncol,2018,30(1):5-14.DOI:10.1016/j.clon.2017.09.007. [62] Milano MT,Usuki KY,Walter KA,et al.Stereotactic radiosurgery and hypofractionated stereotactic radiotherapy:normal tissue dose constraints of the central nervous system[J].Cancer Treat Rev,2011,37(7):567-578.DOI:10.1016/j.ctrv.2011.04.004. [63] Pollom EL,Chin AL,Diehn M,et al.Normal tissue constraints for abdominal and thoracic stereotactic body radiotherapy[J].Semin Radiat Oncol,2017,27(3):197-208.DOI:10.1016/j.semradonc.2017.02.001.
2021, Vol. 30 
