Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-23T16:12:07.439Z Has data issue: false hasContentIssue false

Dosimetric comparison of volumetric modulated arc therapy and intensity modulated radiation therapy for anal cancer

Published online by Cambridge University Press:  01 July 2019

Bing-Hao Chiang
Affiliation:
Department of Radiation Oncology, Peggy & Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
Kerry Hibbitts
Affiliation:
Department of Radiation Oncology, Peggy & Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
Heather Ortega
Affiliation:
Department of Radiation Oncology, Peggy & Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
Terence Herman
Affiliation:
Department of Radiation Oncology, Peggy & Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
Salahuddin Ahmad*
Affiliation:
Department of Radiation Oncology, Peggy & Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
*
Author for correspondence: Salahuddin Ahmad, 800 NE 10th St, SCC L100, Oklahoma City, OK 73104. Tel: (405) 271-3016. E-mail: [email protected]

Abstract

Aim:

Volumetric modulated arc therapy (VMAT), an extension of intensity modulated radiation therapy (IMRT), employs modifications in gantry rotation speed, machine dose rate and multi-leaf collimator motion to deliver a three-dimensional dose distribution. This study compared VMAT to IMRT for patients with anal carcinoma.

Materials and Methods:

Sixteen patients previously treated with IMRT were retrospectively selected. Each patient received a total dose of 57·6–63·0 Gy in 1·8 Gy fractions. A single- or double-isocenter multi-arc VMAT treatment plan was generated using Eclipse RapidArc system with the same computed tomography image sets and optimisation constraints used for IMRT. Dose–volume histograms (DVHs) for planning target volumes (PTVs) and organs at risk (OARs), and monitor units (MUs) and beam on times (BOTs) were used for comparison.

Results:

IMRT and VMAT plans showed insignificant differences in PTV homogeneity and conformity and sparing hips and bowel. VMAT required fewer mean MU and shorter BOT per plan (1,597 MU, 2·66 min) compared to IMRT (2,571 MU, 4·29 min) with p < 0·0001.

Conclusions:

Fewer MU and shorter BOT for VMAT may decrease the damage from secondary radiation and treatment delivery uncertainty due to intra-fraction tumour motion, leading to higher machine throughput and improving patient comfort, with less treatment time.

Type
Technical Note
Copyright
© Cambridge University Press 2019

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

Cancer facts and figures 2018. American Cancer Society Inc., Atlanta, Georgia, USA, 2018.Google Scholar
UKCCCR Anal Cancer Trial Working Party. Epidermoid anal cancer: results from the UKCCCR randomised trial of radiotherapy alone versus radiotherapy, 5-fluorouracil, and mitomycin. Lancet 1996; 348 (9034): 10491054.CrossRefGoogle Scholar
Bartelink, H, Roelofsen, F, Eschwege, Fet al.Concomitant radiotherapy and chemotherapy is superior to radiotherapy alone in the treatment of locally advanced anal cancer: results of a phase III randomized trial of the European organization for research and treatment of cancer radiotherapy and gastrointestinal cooperative groups. J Clin Oncol 1997; 15 (5): 20402049.CrossRefGoogle ScholarPubMed
Flam, M, John, M, Pajak, T Fet al.Role of mitomycin in combination with fluorouracil and radiotherapy, and of salvage chemoradiation in the definitive nonsurgical treatment of epidermoid carcinoma of the anal canal: results of a phase III randomized intergroup study. J Clin Oncol 1996; 14 (9): 25272539.CrossRefGoogle ScholarPubMed
Mundt, A J, Lujan, A E, Rotmensch, Jet al. Intensity-modulated whole pelvic radiotherapy in women with gynecologic malignancies. Int J Radiat Oncol Biol Phys 2002; 52 (5): 13301337.CrossRefGoogle ScholarPubMed
Chen, Y J, Liu, A, Tsai, P Tet al. Organ sparing by conformal avoidance intensity-modulated radiation therapy for anal cancer: dosimetric evaluation of coverage of pelvis and inguinal/femoral nodes. Int J Radiat Oncol Biol Phys. 2005; 63 (1): 274281.CrossRefGoogle ScholarPubMed
Menkarios, C, Azria, D, Laliberté, Bet al.Optimal organ-sparing intensity-modulated radiation therapy (IMRT) regimen for the treatment of locally advanced anal canal carcinoma: a comparison of conventional and IMRT plans. Radiat Oncol 2007; 2 (1): 41. doi: 10.1186/1748-717X-2-41.CrossRefGoogle ScholarPubMed
Mok, H, Briere, T M, Martel, M Ket al.Comparative analysis of volumetric modulated arc therapy versus intensity modulated radiation therapy for radiotherapy of anal carcinoma. Pract Radiat Oncol 2011; 1 (3): 163172.CrossRefGoogle ScholarPubMed
Clivio, A, Fogliata, A, Franzetti-Pellanda, Aet al.Volumetric-modulated arc radiotherapy for carcinomas of the anal canal: a treatment planning comparison with fixed field IMRT. Radiother Oncol 2009; 92 (1): 118124.CrossRefGoogle ScholarPubMed
Vieillot, S, Azria, D, Lemanski, Cet al.Plan comparison of volumetric-modulated arc therapy (RapidArc) and conventional intensity-modulated radiation therapy (IMRT) in anal canal cancer. Radiat Oncol 2010; 5 (1): 92. doi: 10.1186/1748-717X-5-92.CrossRefGoogle Scholar
Stieler, F, Wolff, D, Lohr, Fet al.A Fast radiotherapy paradigm for anal cancer with volumetric modulated arc therapy (VMAT). Radiat Oncol 2009; 4: 48. doi: 10.1186/1748-717X-4-48.CrossRefGoogle Scholar