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Stereotactic radiotherapy for small and very small tumours (≤1 to ≤3 cc): evaluation of the influence of volumetric-modulated arc therapy in comparison to dynamic conformal arc therapy and 3D conformal radiotherapy as a function of flattened and unflattened beam models

Published online by Cambridge University Press:  13 January 2020

Gopinath Mamballikalam*
Affiliation:
R & D, Bharathiar University, Coimbatore, Tamilnadu, India Aster Medcity, Kochi, Kerala, India
S. Senthilkumar
Affiliation:
Department of Radiotherapy, Government Rajaji Hospital & Madurai Medical College, Madurai, Tamil Nadu, India
R. C. Jaon Bos
Affiliation:
Aster Medcity, Kochi, Kerala, India
P. M. Ahamed Basith
Affiliation:
Aster Medcity, Kochi, Kerala, India
P. M. Jayadevan
Affiliation:
Aster Medcity, Kochi, Kerala, India
*
Author for correspondence: Gopinath Mamballikalam, Aster Medcity, Kochi, Kerala, India. E-mail: [email protected]

Abstract

Purpose:

The objective of this article is to evaluate the dosimetric efficacy of volumetric modulated arc therapy (VMAT) in comparison to dynamic conformal arc therapy (DCAT) and 3D conformal radiotherapy (3DCRT) for very small volume (≤1 cc) and small volume (≤3 cc) tumours for flattened (FF) and unflattened (FFF) 6 MV beams.

Materials and methods:

A total of 21 patients who were treated with single-fraction stereotactic radiosurgery, using either VMAT, DCAT or 3DCRT, were included in this study. The volume categorisation was seven patients each in <1, 1–2 and 2–3 cc volume. The treatment was planned with 6 MV FF and FFF beams using three different techniques: VMAT/Rapid Arc (RA) (RA_FF and RA_FFF), dynamic conformal arc therapy (DCA_FF and DCA_FFF) and 3DCRT (Static_FF and Static_FFF). Plans were evaluated for target coverage (V100%), conformity index, homogeneity index, dose gradient for 50% dose fall-off, total MU and MU/dose ratio [intensity-modulated radiotherapy (IMRT) factor], normal brain receiving >12 Gy dose, dose to the organ at risk (OAR), beam ON time and dose received by 12 cc of the brain.

Result:

The average target coverage for all plans, all tumour volumes (TVs) and delivery techniques is 96·4 ± 4·5 (range 95·7 ± 6·1–97·5 ± 2·9%). The conformity index averaged over all volume ranges <1, 2, 3 cc> varies between 0·55 ± 0·08 and 0·68 ± 0·04 with minimum and maximum being exhibited by DCA_FFF for 1 cc and Static_FFF/RA_FFF for 3 cc tumours, respectively. Mean IMRT factor averaged over all volume ranges for RA_FF, DCA_FF and Static_FF are 3·5 ± 0·8, 2·0 ± 0·2 and 2·0 ± 0·2, respectively; 50% dose fall-off gradient varies in the range of 0·33–0·42, 0·35–0·40 and 0·38–0·45 for 1, 2 and 3 cc tumours, respectively.

Conclusion:

This study establishes the equivalence between the FF and FFF beam models and different delivery techniques for stereotactic radiosurgery in small TVs in the range of ≤1 to ≤3 cc. Dose conformity, heterogeneity, dose fall-off characteristics and OAR doses show no or very little variation. FFF could offer only limited time advantage due to excess dose rate over an FF beam.

Type
Original Article
Copyright
© The Author(s), 2020. Published by Cambridge University Press.

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References

Leksell, L. The stereotaxic method and radiosurgery of the brain. Acta Chir Scand 1951 Dec 13; 102 (4): 316319.Google ScholarPubMed
Hakim, R, Alexander, E III, Loeffler, JS et al. Results of linear accelerator-based radiosurgery for intracranial meningiomas. Neurosurgery 1998 Mar 1; 42 (3): 446454.Google ScholarPubMed
Sarkar, B, Pradhan, A, Munshi, A. Do technological advances in linear accelerators improve dosimetric outcomes in stereotaxy? A head-on comparison of seven linear accelerators using volumetric modulated arc therapy-based stereotactic planning. Indian J Cancer 2016 Jan 1; 53 (1): 166173.10.4103/0019-509X.180815CrossRefGoogle ScholarPubMed
Puataweepong, P, Dhanachai, M, Hansasuta, A et al. The clinical outcome of intracranial hemangioblastomas treated with linac-based stereotactic radiosurgery and radiotherapy. J Radiat Res 2014 Jul 1;55 (4): 761768.10.1093/jrr/rrt235CrossRefGoogle ScholarPubMed
Mitsumori, M, Shrieve, DC, Alexander, E et al. Initial clinical results of LINAC-based stereotactic radiosurgery and stereotactic radiotherapy for pituitary adenomas. Int J Radiat Oncol Biol Phys 1998 Oct 1; 42 (3): 573580.10.1016/S0360-3016(98)00256-9CrossRefGoogle ScholarPubMed
Dunbar, SF, Tarbell, NJ, Kooy, HM et al. Stereotactic radiotherapy for pediatric and adult brain tumors: preliminary report. Int J Radiat Oncol Biol Phys 1994 Oct 15; 30 (3): 531–519.CrossRefGoogle ScholarPubMed
Norén, G, Greitz, D, Hirsch, A, Lax, I. Gamma knife surgery in acoustic tumours. Acta Neurochir Suppl (Wien) 1993; 58: 104107.Google ScholarPubMed
Touboul, E, Al Halabi, A, Buffat, L et al. Single-fraction stereotactic radiotherapy: a dose–response analysis of arteriovenous malformation obliteration. Int J Radiat Oncol Biol Phys 1998 Jul 1; 41 (4): 855861 10.1016/S0360-3016(98)00115-1CrossRefGoogle ScholarPubMed
Sarkar, B, Munshi, A, Manikandan, A, Anbazhagan, S, Ganesh, T, Mohanti, BK. Standardization of volumetric modulated arc therapy based frameless stereotactic technique using a multidimensional ensemble aided knowledge based planning. Med Phys 2019 May; 46 (5): 19531962.10.1002/mp.13470CrossRefGoogle ScholarPubMed
Munshi, A, Sarkar, B, Roy, S, Ganesh, T, Mohanti, BK. Dose fall-off patterns with volumetric modulated arc therapy and three-dimensional conformal radiotherapy including the ‘organ at risk’ effect. Experience of linear accelerator-based frameless radiosurgery from a single institution. Cancer/Radiothérapie. 2019 Apr; 23 (2): 138146.10.1016/j.canrad.2018.10.003CrossRefGoogle Scholar
Das, IJ, Ding, GX, Ahnesjö, A. Small fields: nonequilibrium radiation dosimetry. Med Phys 2008 Jan 1;35 (1): 206215.CrossRefGoogle ScholarPubMed
Kataria, T, Sharma, K, Subramani, V, Karrthick, KP, Bisht, SS. Homogeneity index: an objective tool for assessment of conformal radiation treatments. J Med Phys 2012 Oct-Dec; 37 (4): 207213.10.4103/0971-6203.103606CrossRefGoogle ScholarPubMed
Benedict, SH, Yenice, KM, Followill, D et al. Stereotactic body radiation therapy: the report of AAPM Task Group 101. Med Phys 2010; 37: 40784101.10.1118/1.3438081CrossRefGoogle ScholarPubMed
Sarkar, B, Ghosh, B, Sriramprasath, SM, Basu, A, Goswami, J, Ray, A. Optimized point dose measurement for monitor unit verification in intensity modulated radiation therapy using 6 MV photons by three different methodologies with different detector-phantom combinations: a comparative study. J Med Phys/Association of Medical Physicists of India 2010 Jul; 35 (3): 144150.Google ScholarPubMed
Flickinger, JC, Kondziolka, D, Lunsford, LD et al. A multi-institutional experience with stereotactic radiosurgery for solitary brain metastasis. Int J Radiat Oncol Biol Phys 1994 Mar 1; 28 (4): 797802.10.1016/0360-3016(94)90098-1CrossRefGoogle ScholarPubMed
Flickinger, JC, Lunsford, LD, Kondziolka, D et al. Radiosurgery and brain tolerance: an analysis of neurodiagnostic imaging changes after gamma knife radiosurgery for arteriovenous malformations. Int J Radiat Oncol Biol Phys 1992 Jan 1; 23 (1): 1926.10.1016/0360-3016(92)90539-TCrossRefGoogle ScholarPubMed
Khataniar, N, Sarkar, B, Gupta, R, Agrawal, S, Mohanti, B, Munshi, A. EP-1203: post-radiation T2 changes in MRI brain: is there a dose-effect relation? Radiother Oncol 2018 Apr 1; 127: S670S671.10.1016/S0167-8140(18)31513-5CrossRefGoogle Scholar
Kondziolka, D, Nathoo, N, Flickinger, JC, Niranjan, A, Maitz, AH, Lunsford, LD. Long-term results after radiosurgery for benign intracranial tumors. Neurosurgery 2003; 53: 815822.10.1093/neurosurgery/53.4.815CrossRefGoogle ScholarPubMed
Jalali, R, Mallick, I, Dutta, D et al. Factors influencing neurocognitive outcomes in young patients with benign and low-grade brain tumors treated with stereotactic conformal radiotherapy. Int J Radiat Oncol Biol Phys 2010; 77: 974979.CrossRefGoogle ScholarPubMed
Marks, LB, Yorke, ED, Jackson, A et al. Use of normal tissue complication probability models in the clinic. Int J Radiat Oncol Biol Phys 2010 Mar 1; 76 (3): S10S19.CrossRefGoogle ScholarPubMed
Laing, RW, Bentley, RE, Nahumb, AE, Warrington, AP, Brada, M. Stereotactic radiotherapy of irregular targets: a comparison between static conformal beams and non-coplanar arcs. Radiother Oncol 1993; 28: 241246.10.1016/0167-8140(93)90064-FCrossRefGoogle ScholarPubMed
Sarkar, B, Pradhan, A, Munshi, A, Roy, S, Ganesh, T, Mohanti, B. EP-1685: influence of flat, flattening filter free beam model and different MLC’s on VMAT based SRS/SRT. Radiother Oncol 2016 Apr 1; 119: S787.10.1016/S0167-8140(16)32936-XCrossRefGoogle Scholar
Shepard, DM, Yu, C, Murphy, MJ, Bussière, M, Bova, FJ. Treatment planning for stereotactic radiosurgery. In: Chin, L, Regine, W (eds). Principles and Practice of Stereotactic Radiosurgery. New York, NY: Springer, 2015: 6990.Google Scholar
Wu, QJ, Wang, Z, Kirkpatrick, JP et al. Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra-and extracranial lesions. Radiat Oncol 2009; 4: 3. doi:10.1186/1748-717X-4-3 CrossRefGoogle ScholarPubMed
Munshi, A, Sarkar, B, Roy, S, Ganesh, T, Mohanti, BK. EP-1667: dose fall off patterns and the OAR effect-experience of Linac based frameless radiosurgery. Radiother Oncol 2016 Apr 1; 119: S778S779.10.1016/S0167-8140(16)32918-8CrossRefGoogle Scholar
Tanyi, JA, Kato, CM, Chen, Y, Chen, Z, Fuss, M. Impact of the high-definition multileaf collimator on linear accelerator-based intracranial stereotactic radiosurgery. Br J Radiol 2011 Jul; 84 (1003): 629638.CrossRefGoogle ScholarPubMed
Ernst-Stecken, A, Lambrecht, U, Ganslandt, O et al. Radiosurgery of small skull-base lesions. Strahlenther Onkol 2005 May 1; 181 (5): 336344.CrossRefGoogle ScholarPubMed
Monk, JE, Perks, JR, Doughty, D, Plowman, PN. Comparison of a micro-multileaf collimator with a 5-mm-leaf-width collimator for intracranial stereotactic radiotherapy. Int J Radiat Oncol Biol Phys 2003 Dec 1; 57 (5): 14431449.CrossRefGoogle ScholarPubMed
Peng, LC, Kahler, D, Samant, S et al. Quality assessment of frameless fractionated stereotactic radiotherapy using cone beam computed tomography. Int J Radiat Oncol Biol Phys 2010 Dec 1; 78 (5): 15861593.10.1016/j.ijrobp.2010.02.011CrossRefGoogle ScholarPubMed
Sarkar, B, Munshi, A, Krishnankutty, S, Ganesh, T, Kalyan, MB. Positional errors in linear accelerator based frameless cranial stereotaxy: a note of caution. J BUON 2017; 22 (6): 16061607.Google ScholarPubMed
Manikandan, A, Sarkar, B, Holla, R, Vivek, TR, Sujatha, N. Quality assurance of dynamic parameters in volumetric modulated arc therapy. Br J Radiol 2012 Jul; 85 (1015): 10021010.10.1259/bjr/19152959CrossRefGoogle ScholarPubMed
Manikandan, A, Sarkar, B, Nandy, M et al. Detector system dose verification comparisons for arc therapy: couch vs. gantry mount. J Appl Clin Med Phys 2014 May 1; 15 (3): 4153.CrossRefGoogle ScholarPubMed