Document Detail

The radiobiological P(+) index for pretreatment plan assessment with emphasis on four-dimensional radiotherapy modalities.
MedLine Citation:
PMID:  23039677     Owner:  NLM     Status:  In-Data-Review    
Purpose: Radiation treatment modalities will continue to emerge that promise better clinical outcomes albeit technologically challenging to implement. An important question facing the radiotherapy community then is the need to justify the added technological effort for the clinical return. Mobile tumor radiotherapy is a typical example, where 4D tumor tracking radiotherapy (4DTRT) has been proposed over the simpler conventional modality for better results. The modality choice per patient can depend on a wide variety of factors. In this work, we studied the complication-free tumor control probability (P(+)) index, which combines the physical complexity of the treatment plan with the radiobiological characteristics of the clinical case at hand and therefore found to be useful in evaluating different treatment techniques and estimating the expected clinical effectiveness of different radiation modalities.Methods: 4DCT volumes of 18 previously treated lung cancer patients with tumor motion and size ranging from 2 mm to 15 mm and from 4 cc to 462 cc, respectively, were used. For each patient, 4D treatment plans were generated to extract the 4D dose distributions, which were subsequently used with clinically derived radiobiological parameters to compute the P(+) index per modality.Results: The authors observed, on average, a statistically significant increase in P(+) of 3.4% ± 3.8% (p < 0.003) in favor of 4DTRT. There was high variability among the patients with a <0.5% up to 13.4% improvement in P(+).Conclusions: The observed variability in the improvement of the clinical effectiveness suggests that the relative benefit of tracking should be evaluated on a per patient basis. Most importantly, this variability could be effectively captured in the computed P(+). The index can thus be useful to discriminate and hence point out the need for a complex modality like 4DTRT over another. Besides tumor mobility, a wide range of other factors, e.g., size, location, fractionation, etc., can affect the relative benefits. Application of the P(+) objective is a simple and effective way to combine these factors in the evaluation of a treatment plan.
Teboh Roland; Erik Tryggestad; Panayiotis Mavroidis; Russell Hales; Nikos Papanikolaou
Related Documents :
21093617 - Limited pulmonary resection for peripheral small-sized adenocarcinoma of the lung.
12640107 - Oral and salivary gland angiosarcoma: a clinicopathologic study of 29 cases.
8949757 - The neutron therapy clinical programme at the national accelerator centre (nac).
24123027 - Hypofractionation with vmat versus 3dcrt in post-operative patients with prostate cancer.
6871637 - Prognostic factors in locally recurrent rectal carcinoma treated by radiotherapy.
9129927 - Surgical treatment of invasive penile cancer--the heidelberg experience from 1968 to 1994.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Medical physics     Volume:  39     ISSN:  0094-2405     ISO Abbreviation:  Med Phys     Publication Date:  2012 Oct 
Date Detail:
Created Date:  2012-10-08     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0425746     Medline TA:  Med Phys     Country:  United States    
Other Details:
Languages:  eng     Pagination:  6420-30     Citation Subset:  IM    
Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  The use of exit detector sinograms to detect anatomical variations for patients extending beyond the...
Next Document:  Liver motion during cone beam computed tomography guided stereotactic body radiation therapy.