Dataset Information

Imaging prior to radiotherapy impacts in-vitro survival.

ABSTRACT:

Background and purpose

Cone Beam Computed Tomography (CBCT) is routinely used in radiotherapy to identify the position of the target volume. The aim of this study was to determine whether the CBCT dose, when followed by the treatment, influences the therapeutic outcomes as determined by in-vitro clonogenic cell survival in a radiobiological experiment.

Materials and methods

Human cell lines, four cancer and one normal, were exposed to a 6 MV photon beam, produced by a linear accelerator. For half of each sample, a prior imaging dose was delivered using the on-board CBCT. A sample size of n = 103 was used to achieve statistical power.

Results

The experimental group of cell lines exposed to CBCT imaging prior to treatment exhibited a reduction in mean cancer cell survival of ~17 times (p = 0.02) greater than predicted from the average dose response and equivalent to more than 5% of the therapeutic dose, compared to 11 times greater than predicted for normal cells (n.s.).

Conclusion

The greater than predicted reduction in survival resulting from the additional CBCT dose is consistent with radiation-induced bystander effects.

SUBMITTER: Kench PL

PROVIDER: S-EPMC7807556 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Imaging prior to radiotherapy impacts <i>in-vitro</i> survival.

Kench Peter L PL Rogers Linda L Esteves Ana A Gorjiara Tina T Mackonis Elizabeth Claridge EC Morrell Stephen S McKenzie David R DR Suchowerska Natalka N

Physics and imaging in radiation oncology 20201001

<h4>Background and purpose</h4>Cone Beam Computed Tomography (CBCT) is routinely used in radiotherapy to identify the position of the target volume. The aim of this study was to determine whether the CBCT dose, when followed by the treatment, influences the therapeutic outcomes as determined by in-vitro clonogenic cell survival in a radiobiological experiment.<h4>Materials and methods</h4>Human cell lines, four cancer and one normal, were exposed to a 6 MV photon beam, produced by a linear accel ...[more]

PMID: 33458357

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