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A comparative dosimetric study comparing dose to the carotid artery using 3D conformal radiotherapy and intensity-modulated radiotherapy for T1-T2 glottic cancer at Gharbia Cancer Society, Egypt

Published online by Cambridge University Press:  15 February 2017

Mohamed Mahmoud ,
Safa Elfaramawy  and
Maha H. Mokhtar
Mohamed Mahmoud*
Affiliation:
Radiation Oncology Department, National Cancer Institute, Cairo University, Cairo, Egypt
Safa Elfaramawy
Affiliation:
Radiation Physics Department, Gharbia Cancer Society, Gharbia, Egypt
Maha H. Mokhtar
Affiliation:
Radiation Oncology Department, National Cancer Institute, Cairo University, Cairo, Egypt
*
Correspondence to: Mohamed Mahmoud, Radiation Oncology Department, National Cancer Institute, Cairo University, Cairo 11796, Egypt. Tel: +2 010 015 366 81. E-mail: m_mahmoud1973@hotmail.com
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Abstract

Purpose

This is a dosimetric study to compare the feasibility of carotid artery sparing as a primary objective, as well as planning target volume coverage and dose to spinal cord as a secondary objective, by using 3D conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) for patients with early glottis cancer.

Patients and methods

Six patients who had been treated for early stage glottic carcinoma (stage T1-2 N0M0) were included in this study. All patients were immobilised in the supine position with a thermoplastic mask and treatment planning computed tomography scans were obtained from the top of the skull to the top of aortic arch with a 3-mm slice thickness. Two plans were created for every patient, one using 3DCRT and the second using IMRT. Comparison between the two plans was undertaken and analysis was made regarding the dose to the carotids arteries, target coverage and doses to the organs at risk.

Results

For target coverage, the V95% for both plans was the same with no significant difference, hot spots were the highest in 3DCRT with p=0·002, the homogeneity index for IMRT plan was better than 3DCRT (p=0·0001). Regarding the dose to the carotids, it was significantly lower in the IMRT plan compared with the 3DCRT plan (p=0·01). The spinal cord dose was significantly higher in the IMRT plan.

Conclusion

IMRT significantly reduces the radiation dose to the carotid arteries compared with 3DCRT while maintaining clinical target volume coverage. Such a results assists in decreasing the incidence of radiation-induced carotid stenosis, thus improving the quality of life for patients.

Keywords

3DCRTcarotidsIMRTorgans at risktarget coverage
Type
Original Articles
Information
Journal of Radiotherapy in Practice , Volume 16 , Issue 2 , June 2017 , pp. 177 - 182
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Copyright
© Cambridge University Press 2017 

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References

1. Mendenhall, W M, Mancuso, A A, Amdur, R J, Werning, J W. Laryngeal cancer. In: Halperin E C, Brady L W, Perez C A, et al, (eds). Perez and Brady’s Principles and Practice of Radiation Oncology, 6th edition. Philadelphia, PA: Lippincott Williams & Wilkins, 2013: 850–868.Google Scholar
2. Petrakos, I, Kontzoglou, K, Nikolopoulos, T P, Papadopoulos, O, Kostakis, A. Glottic and supraglottic laryngeal cancer: epidemiology, treatment patterns and survival in 164 patients. J BUON 2012; 17: 700–705.Google ScholarPubMed
3. Teshima, T, Chatani, M, Hata, K, Inoue, T. Radiation therapy of early glottic cancer (T1N0M0); retrospective review of historical control. Rinsho Hoshasen 1989; 34: 1603–1606.Google Scholar
4. Gujral, D M, Shah, B N, Chahal, N S, Senior, R, Harrington, K J, Nutting, C M. Clinical features of radiation-induced carotid atherosclerosis. Clin Oncol (R Coll Radiol) 2014; 26: 94–102.Google Scholar
5. Doaa, M A, Ehab, M A H S A, Shady, F, Wafaa, K. Dosimetric comparison of intensity-modulated radiotherapy versus 3D conformal radiotherapy in patients with head and neck cancer. J Multidiscip Eng Sci Technol 2015; 2: 678–683.Google Scholar
6.International commission on radiation units and measurements. J ICRU 2010; 10 (1), report 83.CrossRefGoogle Scholar
7. Brown, P D, Foote, R L, McLaughlin, M P et al. A historical prospective cohort study of carotid artery stenosis after radiotherapy for head and neck malignancies. Int J Radiat Oncol Biol Phys 2005; 63: 1361–1367.CrossRefGoogle ScholarPubMed
8. Smith, G L, Smith, B D, Buchholz, T A et al. Cerebrovascular disease risk in older head and neck cancer patients after radiotherapy. J Clin Oncol 2008; 26: 5119–5125.Google Scholar
9. Dorresteijn, L D, Kappelle, A C, Boogerd, W et al. Increased risk of ischemic stroke after radiotherapy on the neck in patients younger than 60 years. J Clin Oncol 2002; 20: 282–288.CrossRefGoogle ScholarPubMed
10. Rosenthal, D I, Fuller, C D, Barker, J L Jr, et al. Simple carotid-sparing intensity-modulated radiotherapy technique and preliminary experience for T1-2 glottic cancer. Int J Radiat Oncol Biol Phys 2010; 77: 455–461.CrossRefGoogle ScholarPubMed
11. Zumsteg, Z S, Riaz, N, Jaffery, S et al. Carotid sparing intensitymodulated radiation therapy achieves comparable locoregional control to conventional radiotherapy in T1-2N0 laryngeal carcinoma. Oral Oncol 2015; 51: 716–723.CrossRefGoogle ScholarPubMed
12. Hoon, S C, Bae, K J, Hojin, J et al. Carotid sparing intensity modulated radiotherapy on early glottic cancer: preliminary study. Radiat Oncol J 2016; 34 (1): 26–33.Google Scholar