Approaching Oxygen-Guided Intensity-Modulated Radiation Therapy

Approaching Oxygen-Guided Intensity-Modulated Radiation Therapy Full article

Journal

Advances in Experimental Medicine and Biology
ISSN: 0065-2598

Output data

Year: 2016, Volume: 876, Pages: 185-193 Pages count : 9 DOI: 10.1007/978-1-4939-3023-4_23

Tags

Radiation therapy; Oxygen guided therapy; Oxygen imaging; EPRimaging

Authors

Epel Boris ^1,2 , Redler Gage ^1,2 , Pelizzari Charles ^1,2 , Tormyshev Victor M. ^1,3 , Halpern Howard J. ^1,2

Affiliations

1	(Данные Web of science) Univ Chicago, Ctr EPR Imaging In Vivo Physiol, Chicago, IL 60637 USA
2	(Данные Web of science) Univ Chicago, Dept Radiat & Cellular Oncol, Chicago, IL 60637 USA
3	(Данные Web of science) Novosibirsk Organ Chem Inst, Novosibirsk, Russia

The outcome of cancer radiation treatment is strongly correlated with tumor oxygenation. The aim of this study is to use oxygen tension distributions in tumors obtained using Electron Paramagnetic Resonance (EPR) imaging to devise better tumor radiation treatment. The proposed radiation plan is delivered in two steps. In the first step, a uniform 50 % tumor control dose (TCD50) is delivered to the whole tumor. For the second step an additional dose boost is delivered to radioresistant, hypoxic tumor regions. FSa fibrosarcomas grown in the gastrocnemius of the legs of C3H mice were used. Oxygen tension images were obtained using a 250 MHz pulse imager and injectable partially deuterated trityl OX63 (OX71) spin probe. Radiation was delivered with a novel animal intensity modulated radiation therapy (IMRT) XRAD225Cx microCT/radiation therapy delivery system. In a simplified scheme for boost dose delivery, the boost area is approximated by a sphere, whose radius and position are determined using an EPR O-2 image. The sphere that irradiates the largest fraction of hypoxic voxels in the tumor was chosen using an algorithm based on Receiver Operator Characteristic (ROC) analysis. We used the fraction of irradiated hypoxic volume as the true positive determinant and the fraction of irradiated normoxic volume as the false positive determinant in the terms of that analysis. The most efficient treatment is the one that demonstrates the shortest distance from the ROC curve to the upper left corner of the ROC plot. The boost dose corresponds to the difference between TCD90 and TCD50 values. For the control experiment an identical radiation dose to the normoxic tumor area is delivered.

Epel B. , Redler G. , Pelizzari C. , Tormyshev V.M. , Halpern H.J.
Approaching Oxygen-Guided Intensity-Modulated Radiation Therapy

Advances in Experimental Medicine and Biology. 2016. V.876. P.185-193. DOI: 10.1007/978-1-4939-3023-4_23 WOS Scopus РИНЦ

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Web of science	WOS:000373880600024
Scopus	2-s2.0-84958567766
Elibrary	26854516
OpenAlex	W2293836989