Hostname: page-component-68945f75b7-qf55q Total loading time: 0 Render date: 2024-08-05T18:50:52.258Z Has data issue: false hasContentIssue false

Dosimetric comparison of constant dose rate volumetric modulated arc therapy (CDR-VMAT) and intensity-modulated radiation therapy (IMRT) for gallbladder cancer

Published online by Cambridge University Press:  29 December 2020

Varsha R. Gedam*
Affiliation:
Department of Medical Physics, Delhi State Cancer Institute, Dilshad Garden, Delhi; Department of Physics, GLA University, Mathura, India
Anirudh Pradhan
Affiliation:
Department of Mathematics, GLA University, Mathura, Uttar Pradesh, India
*
Author for correspondence: Varsha R. Gedam, Department of Medical Physics, Delhi State Cancer Institute, Dilshad Garden, Delhi, 110095. E-mail: varshadhargave@gmail.com

Abstract

Aim:

To study the feasibility of constant dose rate volumetric modulated arc therapy (CDR-VMAT) in radiotherapy for gallbladder cancer by comparing dosimetric parameter suggested by International Commission on Radiation Units and Measurements-83 (ICRU-83) with step and shoot intensity-modulated radiation therapy (SS IMRT).

Methods:

For this study, we selected 21 post-operative gallbladder cancer patients, which were treated with the IMRT technique from 2016 to 2019. For each patient, we generated SS IMRT plan and CDR-VMAT plan and were dosimetrically compared by parameters suggested by ICRU-83 for PTV. Homogeneity Index (HI) and Conformity Index (CI) were also calculated. For evaluation of Organ at Risk (OAR), we compared the mean doses, volume doses to the right kidney, left kidney, both kidneys combined, liver and max dose to the spinal cord. Monitor units (MUs) and treatment delivery time were also compared.

Results:

On comparing, we found that CDR-VMAT plans were highly conformed as CI and PCI (CI define by Paddick) were found more (0·98 ± 0·01 vs. 0·97 ± 0·03 and 0·86 ± 0·05 vs. 0·85 ± 0·05) than IMRT plans but not statistically significant. Better dose HI was found for IMRT plans with statistical significant difference (p < 0·001). The tumour coverage was found similar 98·24% and 97·83% for SS IMRT and CDR-VMAT, respectively. For D2%, the maximum dose to PTV was significantly lower in IMRT (p = 0·001). D50% and mean dose to PTV were also comparable to IMRT with no statistically significant difference. The OAR parameters were comparable in both the techniques. The mean doses and volume doses V10, V20 and V30 to the right kidney, left kidney and liver were also comparable with no significant difference (p > 0·05) was noted among them. However, the maximum dose to the spinal cord was significantly less in CDR-VMAT (21·1 Gy vs. 25·1Gy) than SS IMRT with p = 0·006. More MUs were associated with the CDR-VMAT technique, but shorter treatment delivery time than the IMRT technique.

Conclusions:

On dosimetric comparison of two treatment techniques, we conclude that CDR-VMAT can be a valid option in radiotherapy as it achieved highly conformed dose distribution, comparable tumour coverage and OAR sparing as IMRT technique for gallbladder cancer.

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bartlett, D L. Gallbladder cancer. Semin Surg Oncol 2000; 19: 145155.3.0.CO;2-6>CrossRefGoogle ScholarPubMed
Ferlay, J, Soerjomataram, I, Ervik, M et al. GLOBOCAN 2012 v1.0, Cancer Incidence and Mortality Worldwide: IARC CancerBase No. 11 [Internet]. Lyon, France: International Agency for Research on Cancer; 2013.Google Scholar
Mojica, P, Smith, D, Ellenhorn, J. Adjuvant radiation therapy is associated with improved survival for gallbladder carcinoma with regional metastatic disease. J Surg Oncol 2007; 96: 813.CrossRefGoogle ScholarPubMed
Todoroki, T, Ohara, K, Kawamoto, T et al. Benefits of adjuvant radiotherapy after radical resection of locally advanced main hepatic duct carcinoma. Int J Radiat Oncol Biol Phys 2000; 46: 581587.-(survival).CrossRefGoogle ScholarPubMed
Kresl, J J, Schild, S E, Henning, G T et al. Adjuvant external beam radiation therapy with concurrent chemotherapy in the management of gallbladder carcinoma. Int J Radiat Oncol Biol Phys 2002; 52: 167175-(survival).CrossRefGoogle ScholarPubMed
Houry, S, Schlienger, M, Huguier, M, Lacaine, F, Penne, F, Laugier, A. Gallbladder carcinoma: role of radiation therapy. Br J Surg 1989; 76: 448450.CrossRefGoogle Scholar
Smoron, G L. Radiation therapy of carcinoma of gallbladder and biliary tract. Cancer 1977; 40: 14221424.3.0.CO;2-1>CrossRefGoogle ScholarPubMed
Czito, B G, Hurwitz, H I, Clough, R W et al. Adjuvant external-beam radiotherapy with concurrent chemotherapy after resection of primary gallbladder carcinoma: a 23-year experience. Int J Radiat Oncol Biol Phys 2005; 62: 10301034.CrossRefGoogle ScholarPubMed
Itoh, H, Nishijima, K, Kurosaka, Y et al. Magnitude of combination therapy of radical resection and external beam radiotherapy for patients with carcinomas of the extrahepatic bile duct and gallbladder. Dig Dis Sci 2005; 50: 22312242.CrossRefGoogle ScholarPubMed
Sun, X -N, Wang, Q, Gu, B -X, et al. Adjuvant radiotherapy for gallbladder cancer: a dosimetric comparison of conformal radiotherapy and intensity-modulated radiotherapy. World J Gastroenterol 2011; 17 (3): 397402.CrossRefGoogle ScholarPubMed
Mackie, T R, Holmes, T W, Reckwerdt, P J et al. A proposal for a dedicated computer controlled delivery and verification system for conformal radiotherapy. In: Proceedings of the XIth International Conference on the use of Computers in Radiation therapy. Manchester, UK, 1994: 176177.Google Scholar
Mackie, T R, Holmes, T W, Swerdloffff, S et al. A new concept for the delivery of conformal radiotherapy. Med Phys 1993; 20: 17091719.CrossRefGoogle ScholarPubMed
Otto, K. Volumetric modulated arc therapy: IMRT in a single gantry arc. Med Phys 2008; 35: 310317.CrossRefGoogle Scholar
Brahme, A, Roos, F E, Lax, I. Solution of an integral equation encountered in rotational therapy. Phys Med Biol 1982; 27: 12211229.CrossRefGoogle Scholar
Cozzi, L, Dinshaw, K A, Shrivastava, S K et al. A treatment planning study comparing volumetric arc modulation with RapidArc and fixed field IMRT for cervix uteri radiotherapy. Radiother Oncol 2008; 89: 180191.CrossRefGoogle ScholarPubMed
Pesce, G A, Clivio, A, Cozzi, L et al. Early clinical experience of radiotherapy of prostate cancer with volumetric modulated arc therapy. Radiat Oncol 2010; 5: 54.CrossRefGoogle ScholarPubMed
The International Commission on Radiation Units and Measurements. J ICRU 2010; 10 (1). Report 83 Oxford University Press doi: 10.1093/jicru/ndq001 Google Scholar
Shaw, E, Scott, C, Souhami, L et al. Radiosurgery for the treatment of previously irradiated recurrent primary brain tumors and brain metastases: initial report of radiation therapy oncology group protocol 90-05. Int J Radiat Oncol Biol Phys 1996; 34 (3): 647654.CrossRefGoogle ScholarPubMed
Paddick, I. A simple scoring ratio to index the conformity of radiosurgical treatment plans. J Neurosurg 2000; 3 (93): 219222.CrossRefGoogle Scholar
Hatanaka, S, Tamaki, S, Endo, H, Mizuno, N, Nakamura, N. Utility of Smart Arc CDR for intensity-modulated radiation therapy for prostate cancer. J Radiation Res 2014; 55: 774779.CrossRefGoogle ScholarPubMed
Yu, W, Shang, H, Xie, C, et al. Feasibility of CDR-VMAT in the treatment of nasopharyngeal cancer patients. Radiat Oncol 2014; 9: 235.CrossRefGoogle ScholarPubMed
Palma, D, Vollans, E, James, K et al. Volumetric modulated arc therapy (VMAT) for delivery of prostate radiotherapy: reduction in treatment time and monitor unit requirements compared to intensity modulated radiotherapy. Int J Radiat Oncol Biol Phys 2008; 76: S312.CrossRefGoogle Scholar
Didona, A, Lancellotta, V, Zucchetti, C, et al. Is volumetric modulated arc therapy with constant dose rate a valid option in radiation therapy for head and neck cancer patients? Rep Pract Oncol Radiother 2018; 23 (3): 175182.CrossRefGoogle Scholar
Yang, R, Wang, J, Xu, F, Li, H, Zhang, X Feasibility of volumetric modulated arc therapy with constant dose rate for endometrial cancer. Med Dosim 2013; 38: 351355.CrossRefGoogle ScholarPubMed
Tang, G, Earl, M A, Yu, C X. Variable dose rate single-arc IMAT delivered with a cosntant dose rate and variable angular spacing. Phys Med Biol 2009; 54: 64396456.CrossRefGoogle Scholar
Iori, M, Cattaneo, G M, Cagni, E et al. Dose-Volume and biological-model based comparison between helical tomotherapy and (inverse-planned) IMAT for prostate tumours. Radiother Oncol 2008; 88: 3445.CrossRefGoogle ScholarPubMed
McGarry, C K, McMahon, S J, Craft, D, O’Sullivan, J M, Prise, K M, Hounsell, A R. Inverse planned constant dose rate volumetric modulated arc therapy (VMAT) as an efficient alternative to five-field intensity modulated radiation therapy (IMRT) for prostate. J Radiother Pract 2014; 13: 6878.CrossRefGoogle Scholar