Comparison of dosimetry distribution between three-dimension conformal and intensity modulated plan integrated with breath motion in postoperative radiation of gastric cancer
10.3760/cma.j.issn.1004-4221.2010.06.014
- VernacularTitle:整合呼吸因素后三维适形及调强放疗计划在胃癌术后放疗中的剂量学研究
- Author:
Wenjie SUN
;
Zhen ZHANG
;
Weigang HU
;
Weilie GU
;
Ji ZHU
;
Guichao LI
;
Gang CAI
;
Xuejun MA
- Publication Type:Journal Article
- Keywords:
Gastric neoplasms/radiotherapy;
Radiotherapy,three-dimension conformal or intensity modulated;
Organ motion;
Free breathing
- From:
Chinese Journal of Radiation Oncology
2010;19(6):528-531
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the dose distribution of the target and normal tissues in gastric cancers between three-dimension conformal radiation therapy (3DCRT) and intensity modulated radiation therapy (IMRT) plan when respiratory motion factors integrated in the plan. Methods From January 2005to November 2006, 10 patients with post-operatively radiation of gastric cancer were enrolled in this study.Planning CT were acquired conventionally with free-breath mode and the static treatment plans of the 3DCRT and IMRT were designed respectively. Probability distribution functions (PDF) were generated and convoluted with the static dose distributions from 3DCRT and IMRT plans to obtain the integrated plans. The dose distributions of the target and normal tissues were compared between 3DCRT and IMRT integration treatment plans, such as V45 of clinical target volume, V4o of liver and V15, V18 of left and right kidney.Results In the respiratory integrated treatment planning, the target volume coverage and homogeneity with IMRT are superior to those with 3DCRT ( ( V45 98%∶ 87% (t = -3. 35 ,P =0. 010) ,mean dose 46. 81 Gy ±0. 75 Gy∶45.99 Gy ± 1.12 Gy (t = -0. 31 ,P=0. 020) ). The V40 of teh liver in IMRT are smaller than those in 3DCRT ( 12%∶ 16% ;t=3.75,P=0.010). For the left kidney, the V15 and V18 in IMRT are smaller than those in 3DCRT ( (34%∶ 50% (t = 2. 17 ,P = 0. 050) and 27%∶46% (t = 3. 11 ,P = 0. 020) ),but for the right kidney, V15 and V18 in 3DCRT are smaller than those in IMRT ( ( 15%∶ 21% (t = - 2. 42,P=0.040) and 11%∶15% (t= -2.71,P=0.030)). Conclusions When respiratory motion factor integrated in the treatment plan, IMRT showed advantage both in target coverage and normal tissue sparing in the high dose region of liver and left kidney.
