Home About us Editorial board Ahead of print Current issue Search Archives Submit article Instructions Subscribe Contacts Login 
ORIGINAL ARTICLE
Year : 2011  |  Volume : 7  |  Issue : 1  |  Page : 58-63

Intensity-modulated radiation to spare neural stem cells in brain tumors: A computational platform for evaluation of physical and biological dose metrics


Department of Advanced Centre for Radiation Oncology, Dr. Balabhai Nanavati Hospital, Mumbai - 400 056, Maharashtra, India

Correspondence Address:
Arun Jaganathan
Advance Centre for Radiation Oncology, Dr. Balabhai Nanavati Hospital, S. V. Road, Vile Parle West, Mumbai - 400 056, Maharashtra
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0973-1482.80463

Rights and Permissions

Background: Neurocognitive effects following whole-brain and partial-brain irradiation can cause considerable morbidity. Sparing of neural stem cells (NSCs) is proposed as an avenue for reducing the long-term radiation-induced defects in learning, memory, and intelligence. We performed an analytical study to spare the NSC from partial-brain irradiation by intensity-modulated radiotherapy (IMRT). Objective: The aim of this study is to achieve maximal sparing of NSC during irradiation of brain tumors using biologically equivalent dose (BED) for all plans. The consequent clinical benefit will possibly be in terms of acute effects on stem cells and delayed neurologic sequelae to brain. A tool to modulate various physical and biological dose metrics has been used to study the optimization of radiation therapy for brain tumors with constraints imposed on total radiation to NSC. Materials and Methods: A total of 10 successive patients of grade III and IV gliomas of brain, who underwent total or near total excision of brain tumors, were included in the study. Patients underwent computed tomography and magnetic resonance imaging fusion for contouring. Computational codes used to analyze the efficacy of the plan are quality of coverage, homogeneity index, and conformity index. Wide range of radiosensitivity parameters were evaluated by using equivalent uniform dose and tumor control probability (TCP) to predict tumor control with and without sparing of NSC. Results: The physical and biological dose metrics were modulated by fitting standard deviation of 0.3% for all plans. The maximum NSC sparing was achieved in IMRT plans with constraints applied to local TCP. Similarly, for BED of plans with and without constraints, the estimated mean reduction in acute complications of NSC achieved was 12.23% (range, 4.27-28.33%). The estimated mean reduction in BED for late complications of late-reacting brain tissue is 14.69% (range, 7.39-33.56%).


[FULL TEXT] [PDF]*
Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)
 

 Article Access Statistics
    Viewed3072    
    Printed223    
    Emailed2    
    PDF Downloaded336    
    Comments [Add]    
    Cited by others 1    

Recommend this journal