Carotid sparing intensity modulated radiotherapy on early glottic cancer: preliminary study.
- Author:
Hoon Sik CHOI
1
;
Bae Kwon JEONG
;
Hojin JEONG
;
Jin Ho SONG
;
Jin Pyeong KIM
;
Jung Je PARK
;
Seung Hoon WOO
;
Ki Mun KANG
Author Information
- Publication Type:Original Article
- Keywords: Carotid arteries; Intensity-modulated radiotherapy; Glottic cancer
- MeSH: Atherosclerosis; Carotid Arteries; Follow-Up Studies; Humans; Radiotherapy*; Radiotherapy, Intensity-Modulated; Recurrence; Risk Factors; Spinal Cord
- From:Radiation Oncology Journal 2016;34(1):26-33
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: To compare the dose distribution between carotid sparing intensity modulated radiotherapy (IMRT) and opposed lateral field technique (LAFT), and to determine the effects of carotid sparing IMRT in early glottic cancer patients who have risk factors for atherosclerosis. MATERIALS AND METHODS: Ten early glottic cancer patients were treated with carotid sparing IMRT. For each patient, the conventional LAFT plan was developed for comparison. IMRT and LAFT plans were compared in terms of planning target volume (PTV) coverage, conformity index, homogeneity index, and the doses to planning organ at risk volume (PRV) for carotid arteries, spinal cord and pharyngeal constrictor muscle. RESULTS: Recurrence was not observed in any patients during the follow-up period. V95% for PTV showed no significant difference between IMRT and LAFT plans, while V100% was significantly higher in the IMRT plan (95.5% vs. 94.6%, p = 0.005). The homogeneity index (11.6%) and conformity index (1.4) in the IMRT plan were significantly better than those in the LAFT plans (8.5% and 5.1, respectively) (p = 0.005). The median V5Gy (90.0%), V25Gy (13.5%), and V50Gy (0%) for carotid artery PRV in the IMRT plan were significantly lower than those in the LAFT plan (99.1%, 89.0%, and 77.3%, respectively) (p = 0.005). CONCLUSION: Our study suggests that carotid sparing IMRT can significantly decrease the dose to carotid arteries compared to LAFT, and it would be considered for early glottic cancer patient with high risk of atherosclerosis.
