Single-fraction simulation of relative cell survival in response to uniform versus hypoxia-targeted dose escalation
| Autor: | Andrei Pugachev, M. Axente, Peck Sun Lin |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Cell Survival
Partial volume Models Biological Lesion Cell Line Tumor Neoplasms medicine Humans Radiology Nuclear Medicine and imaging Irradiation Radiological and Ultrasound Technology medicine.diagnostic_test business.industry Chemistry Dose fractionation Hypoxia (environmental) Tumor Oxygenation Cell Hypoxia Positron emission tomography Cell culture Positron-Emission Tomography Cancer research Dose Fractionation Radiation medicine.symptom Nuclear medicine business |
| Zdroj: | Physics in Medicine and Biology. 57:2757-2774 |
| ISSN: | 1361-6560 0031-9155 |
| DOI: | 10.1088/0031-9155/57/9/2757 |
| Popis: | The purpose of this study was to investigate the increase in cell kill that can be achieved by tumor irradiation with heterogeneous dose distributions targeting hypoxic regions that can be visualized with non-invasive imaging. Starting with a heterogeneous distribution of microvessels, a microscopic two-dimensional model of tumor oxygenation was developed using planar simulation of oxygen diffusion. Non-invasive imaging of hypoxia was simulated taking partial volume effect into account. A dose-modulation scheme was implemented with the goal of delivering higher doses to the hypoxic pixels, as seen in simulated hypoxia images. To determine the relative cell kill in response to hypoxia-targeting irradiation, tumor cell survival fractions were compared to those resulting from treatments delivering the same average dose to the lesion in a spatially uniform fashion. It was shown that hypoxia-targeting dose modulation may be better suited for tumors with low α/β, low hypoxic fraction and spatially aggregated hypoxic features. Most importantly, it was determined that at low fraction doses there is no cell kill increase from targeting hypoxic regions alone versus escalating the total tumor dose. However, for higher doses per fraction (≥8 Gy/fraction), the effectiveness of hypoxia-targeting irradiation increases, resulting in the tumoricidal effect of up to 30% higher than that of uniform tumor irradiation delivering the same average tumor dose. |
| Databáze: | OpenAIRE |
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