Limits...
Application of Volumetric Modulated Arc Therapy and Simultaneous Integrated Boost Techniques to Prepare "Safe Margin" in the Rabbit VX2 Limb Tumor Model.

Wang CW, Zhou Y, Bai JP, Liu H, Liu Y, Shi GL, Ding JJ, Ma DH, Li WT, Xie PM, Yan Y - Med. Sci. Monit. (2015)

Bottom Line: After radiotherapy, the two groups showed a significant difference in the GTVboost area.The 3D-PDA observation showed that tumor vascular structures decreased significantly.The formation of a necrotic zone can be effectively defined as safe margin in the GTVboost area. showing potential clinical applicability.

View Article: PubMed Central - PubMed

Affiliation: Department of Bone and Soft Tissue, The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China (mainland).

ABSTRACT

Background: In this study, we aimed to establish the rabbit VX2 limb tumor model, and then prepare a "necrotic zone" as a safe margin by volumetric modulated arc therapy and simultaneous integrated boost (VMAT-SIB) technique applied in the areas where the tumor is located adjacent to the bone (GTVboost area).

Material and methods: Rabbits in the control group (n=10) were not treated, while those in the test group (n=10) were treated with the SIB schedule delivering a dose of 40Gy, 35Gy, 30Gy, and 25Gy to the GTVboost, GTV (gross tumor volume), CTV (clinical target volume), and PTV (planning target volume) in 10 fractions. Magnetic resonance diffusion-weighted imaging (MRDWI), 3-dimensional power Doppler angiography (3D-PDA), and histological changes were observed after radiotherapy.

Results: After radiotherapy, the two groups showed a significant difference in the GTVboost area. In the test group, the tumor necrosis showed a significantly low signal in DWI and high signal in apparent diffusion coefficient (ADC) maps. The 3D-PDA observation showed that tumor vascular structures decreased significantly. Histological analysis demonstrated that a necrotic zone could be generated in the GTVboost area, and microscopic examination observed cell necrosis and fibroplasia.

Conclusions: This studies demonstrated the feasibility of using VMAT-SIB technique in the rabbit VX2 limb tumor model. The formation of a necrotic zone can be effectively defined as safe margin in the GTVboost area. showing potential clinical applicability.

No MeSH data available.


Related in: MedlinePlus

3D-PDA images of two groups after radiotherapy. The control group displayed some vessel network with tortuous pathways inside the tumor, and peripheral thick vessels were observed (A). In the test group, tumor vascular structures decreased significantly, and only dot- and line-like vessels were observed around the tumor (B). Red arrow: femur.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4544349&req=5

f5-medscimonit-21-2397: 3D-PDA images of two groups after radiotherapy. The control group displayed some vessel network with tortuous pathways inside the tumor, and peripheral thick vessels were observed (A). In the test group, tumor vascular structures decreased significantly, and only dot- and line-like vessels were observed around the tumor (B). Red arrow: femur.

Mentions: The 3D-PDA analysis detected significant difference between the control and the test groups, as significantly decreased vascularization was observed at the GTVboost area in the test group. Based on the criteria of blood vessel classification, 2 and 8 vessels in the control group were classified as type II and type III vessels, respectively (Table 1). The control group displayed some vessel network with tortuous pathways inside the tumor, and peripheral thick vessels were observed (Figure 5A). In the test group, however, 9 vessels were classified as type I and only one was classified as type II. Tumor vascular structures decreased significantly, as no vessel distribution was detected in the tumor, and only dot- and line-like vessels were observed around the tumor (Figure 5B).


Application of Volumetric Modulated Arc Therapy and Simultaneous Integrated Boost Techniques to Prepare "Safe Margin" in the Rabbit VX2 Limb Tumor Model.

Wang CW, Zhou Y, Bai JP, Liu H, Liu Y, Shi GL, Ding JJ, Ma DH, Li WT, Xie PM, Yan Y - Med. Sci. Monit. (2015)

3D-PDA images of two groups after radiotherapy. The control group displayed some vessel network with tortuous pathways inside the tumor, and peripheral thick vessels were observed (A). In the test group, tumor vascular structures decreased significantly, and only dot- and line-like vessels were observed around the tumor (B). Red arrow: femur.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4544349&req=5

f5-medscimonit-21-2397: 3D-PDA images of two groups after radiotherapy. The control group displayed some vessel network with tortuous pathways inside the tumor, and peripheral thick vessels were observed (A). In the test group, tumor vascular structures decreased significantly, and only dot- and line-like vessels were observed around the tumor (B). Red arrow: femur.
Mentions: The 3D-PDA analysis detected significant difference between the control and the test groups, as significantly decreased vascularization was observed at the GTVboost area in the test group. Based on the criteria of blood vessel classification, 2 and 8 vessels in the control group were classified as type II and type III vessels, respectively (Table 1). The control group displayed some vessel network with tortuous pathways inside the tumor, and peripheral thick vessels were observed (Figure 5A). In the test group, however, 9 vessels were classified as type I and only one was classified as type II. Tumor vascular structures decreased significantly, as no vessel distribution was detected in the tumor, and only dot- and line-like vessels were observed around the tumor (Figure 5B).

Bottom Line: After radiotherapy, the two groups showed a significant difference in the GTVboost area.The 3D-PDA observation showed that tumor vascular structures decreased significantly.The formation of a necrotic zone can be effectively defined as safe margin in the GTVboost area. showing potential clinical applicability.

View Article: PubMed Central - PubMed

Affiliation: Department of Bone and Soft Tissue, The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China (mainland).

ABSTRACT

Background: In this study, we aimed to establish the rabbit VX2 limb tumor model, and then prepare a "necrotic zone" as a safe margin by volumetric modulated arc therapy and simultaneous integrated boost (VMAT-SIB) technique applied in the areas where the tumor is located adjacent to the bone (GTVboost area).

Material and methods: Rabbits in the control group (n=10) were not treated, while those in the test group (n=10) were treated with the SIB schedule delivering a dose of 40Gy, 35Gy, 30Gy, and 25Gy to the GTVboost, GTV (gross tumor volume), CTV (clinical target volume), and PTV (planning target volume) in 10 fractions. Magnetic resonance diffusion-weighted imaging (MRDWI), 3-dimensional power Doppler angiography (3D-PDA), and histological changes were observed after radiotherapy.

Results: After radiotherapy, the two groups showed a significant difference in the GTVboost area. In the test group, the tumor necrosis showed a significantly low signal in DWI and high signal in apparent diffusion coefficient (ADC) maps. The 3D-PDA observation showed that tumor vascular structures decreased significantly. Histological analysis demonstrated that a necrotic zone could be generated in the GTVboost area, and microscopic examination observed cell necrosis and fibroplasia.

Conclusions: This studies demonstrated the feasibility of using VMAT-SIB technique in the rabbit VX2 limb tumor model. The formation of a necrotic zone can be effectively defined as safe margin in the GTVboost area. showing potential clinical applicability.

No MeSH data available.


Related in: MedlinePlus