Volumetric modulated arc radiotherapy for carcinomas of the oro-pharynx, hypo-pharynx and larynx: A treatment planning comparison with fixed field IMRT

被引：261

作者：

Vanetti, Eugenio

Clivio, Alessandro

Nicolini, Giorgia

Fogliata, Antonella

Ghosh-Laskar, Sarbani ^{[2
,3
]}

Agarwal, Jai Prakash ^{[2
,3
]}

Upreti, Ritu Raj ^{[2
,3
]}

Budrukkar, Ashwini ^{[2
,3
]}

Murthy, Vedang ^{[2
,3
]}

Deshpande, Deepak Dattatray ^{[2
,3
]}

Shrivastava, Shyam Kishore ^{[2
,3
]}

Dinshaw, Ketayun Ardeshir ^{[2
,3
]}

Cozzi, Luca ^{[1
]}

机构：

[1] Oncol Inst So Switzerland, Dept Radiat Oncol, Med Phys Unit, CH-6504 Bellinzona, Switzerland

[2] Tata Mem Hosp, Dept Radiat Oncol, Mumbai 400012, Maharashtra, India

[3] Tata Mem Hosp, Dept Med Phys, Mumbai 400012, Maharashtra, India

来源：

RADIOTHERAPY AND ONCOLOGY | 2009年 / 92卷 / 01期

关键词：

RapidArc; IMRT; Head and neck radiation therapy; DOSE CALCULATION ALGORITHMS; RADIATION-THERAPY; CLINICAL IMPLEMENTATION; INTENSITY; HEAD; IMAT;

D O I：

10.1016/j.radonc.2008.12.008

中图分类号：

R73 [肿瘤学];

学科分类号：

100214 ;

摘要：

Purpose: A planning study was performed to evaluate the performance of volumetric modulated arc radiotherapy on head and neck cancer patients. Conventional fixed field IMRT was used as a benchmark. Methods and materials: CT datasets of 29 patients with squamous cell carcinoma of the oro-pharynx, hypo-pharynx and larynx were included. Plans for fixed beam IMRT, single (RA1) and double (RA2) modulated arcs with the RapicArc technique were optimised. Dose prescription was set to 66 Gy to the primary tumour (at 2.2 Gy/fraction), 60 Gy to intermediate-risk nodes and 54 Gy to low-risk nodal levels. The planning objectives for PTV were minimum dose >95%. and maximum dose <107%. Maximum dose to spinal cord was limited to 46 Gy, maximum to brain stem to 50 Gy. For parotids, mean dose <26 Gy (or median <30Gy) was assumed as the objective. The MU and delivery time were scored to measure expected treatment efficiency. Results: Target coverage and homogeneity results improved with RA2 plans compared to both RA1 and IMRT. All the techniques fulfilled the objectives on Maximum dose, while small deviations were observed on minimum dose for PTV. The conformity index (CI95%) Was 1.7 +/- 0.2 for all the three techniques. RA2 allowed a reduction of D-2% to spinal cord of similar to 3 Gy compared to IMRT (RA1 D-2% increased it of similar to 1 Gy). On brain stem, D-2% was reduced from 12 Gy (RA1 vs. IMRT) to 13.5 Gy (RA2 vs. IMRT). The mean dose to ipsi-lateral parotids was reduced from 40 Gy (IMRT) to 36.2 Gy (RA1) and 34.4 Gy (RA2). The mean dose to the contra-lateral gland ranged from 32.6 Gy (IMRT) to 30.9 Gy (RA1) and 28.2 Gy (RA2). Conclusion: RapidArc was investigated for head and neck cancer. RA1 and RA2 showed some improvements in organs at risk and healthy tissue sparing, while only RA2 offered improved target coverage with respect to conventional IMRT. (C) 2009 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 92 (2009) 111-117

引用

页码：111 / 117

页数：7

共 29 条

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