Comparative Analysis of the Effective Dose in Craniospinal Irradiation of Pediatric Patients Between Helical Tomotherapy and Multi-Isocenter Intensity Modulated Radiation Therapy

Objectives: To quantify the risk of radiogenic second cancer in pediatric patients receiving hippocampal-sparing craniospinal irradiation either with intensity-modulated radiation therapy or tomotherapy due to the development of a solid second cancer after radiotherapy using the concept of excess absolute risk. Methods: Computed tomography images of 15 pediatric patients who received craniospinal irradiation treatment were selected for this study. For each case, intensity-modulated radiation therapy and tomotherapy plans were computed. Then, the dosimetry parameters were analyzed. Differential dose–volume histograms were generated, and the excess absolute risks were calculated for each plan of each patient. Results: The tomotherapy group was superior to the intensity-modulated radiation therapy group in target area homogeneity index ( P < .001). Tomotherapy offered greater hippocampal sparing than intensity-modulated radiation therapy in terms of D 2% (15.66 vs 23.05 Gy, P < .001) and Dmean (9.79 vs 20.29 Gy, P < .001). Tomotherapy craniospinal irradiation induced a much higher risk than intensity-modulated radiation therapy craniospinal irradiation to the thyroid and lungs (excess absolute risk: thyroid 28.7 vs 26.9 per 10 000 PY, P = .010; lung 20.5 vs 18.9 per 10 000 PY, P = .003). Both techniques conferred a higher risk to the stomach, but there was little difference. In addition, the 2 plans induced less carcinogenic risk to the liver (excess absolute risk 4.2 vs 4.0 per 10 000 PY, P = .020). Conclusions: The tomotherapy plan has obvious advantages in the protection of the hippocampus for children undergoing craniospinal irradiation treatment. Tomotherapy increased the risk of radiogenic second cancer in organ at risk, and therefore, it is imperative to take the risk factor into consideration in the formulation of treatment protocols.

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Influence of tumor location on the intensity-modulated radiation therapy plan of helical tomotherapy

Medical Dosimetry ◽

10.1016/j.meddos.2017.07.003 ◽

2017 ◽

Vol 42 (4) ◽

pp. 334-340 ◽

Cited By ~ 2

Author(s):

Yingjie Xu ◽

Hui Yan ◽

Zhihui Hu ◽

Pan Ma ◽

Kuo Men ◽

...

Keyword(s):

Radiation Therapy ◽

Helical Tomotherapy ◽

Intensity Modulated Radiation Therapy ◽

Tumor Location ◽

Intensity Modulated

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Encouraging Early Clinical Outcomes With Helical Tomotherapy–Based Image-Guided Intensity-Modulated Radiation Therapy for Residual, Recurrent, and/or Progressive Benign/Low-Grade Intracranial Tumors: A Comprehensive Evaluation

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2010.12.044 ◽

2012 ◽

Vol 82 (2) ◽

pp. 756-764 ◽

Cited By ~ 10

Author(s):

Tejpal Gupta ◽

Tabassum Wadasadawala ◽

Zubin Master ◽

Reena Phurailatpam ◽

Rajershi Pai-Shetty ◽

...

Keyword(s):

Radiation Therapy ◽

Clinical Outcomes ◽

Helical Tomotherapy ◽

Comprehensive Evaluation ◽

Intensity Modulated Radiation Therapy ◽

Low Grade ◽

Intracranial Tumors ◽

Image Guided ◽

Intensity Modulated ◽

Early Clinical Outcomes

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Actual Anatomical and Dosimetric Changes of Parotid Glands in Nasopharyngeal Carcinoma Patients during Intensity Modulated Radiation Therapy

BioMed Research International ◽

10.1155/2015/670327 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Gang Ren ◽

Shou-Ping Xu ◽

Lei Du ◽

Lin-Chun Feng ◽

Bao-Lin Qu ◽

...

Keyword(s):

Radiation Therapy ◽

Nasopharyngeal Carcinoma ◽

Volume Change ◽

Helical Tomotherapy ◽

Intensity Modulated Radiation Therapy ◽

Planning System ◽

Parotid Glands ◽

Intensity Modulated ◽

Data Comparison ◽

Clinical Benefits

The goal of this study was to evaluate the actual anatomical and dosimetric changes of parotid glands in nasopharyngeal carcinoma patients during intensity modulated radiation therapy. With helical tomotherapy, its planning system, and adaptive software, weekly anatomical and dosimetric changes of parotid glands in 35 NPC patients were evaluated. Interweekly parotid volume varied significantly (P<0.03). The rate of volume change reached the highest level at the 16th fraction. The averageV1increased by 32.2 (left) and 28.6 (right), and the averageD50increased by 33.9 (left) and 24.93 (right), respectively. Repeat data comparison indicated that theV1andD50varied significantly among different fractions (both withP=0.000). The variation of parotid volume was inversely correlated with that of theV1andD50(both withP=0.000). In conclusion, parotid volume and actual dose vary significantly in NPC patients during IMRT. Replanning at the end of the fourth week of IMRT may have clinical benefits.

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