157
Views
4
CrossRef citations to date
0
Altmetric
ORIGINAL ARTICLE

Assessing patient characteristics and radiation-induced non-targeted effects in vivo for high dose-rate (HDR) brachytherapy

, , , , , , & show all
Pages 786-794 | Received 18 Dec 2014, Accepted 27 Jun 2015, Published online: 18 Sep 2015
 

Abstract

Purpose: To test whether blood, urine, and tissue based colony-forming assays are a useful clinical detection tool for assessing fractionated treatment responses and non-targeted radiation effects in bystander cells.

Materials and methods: To assess patients’ responses to radiation treatments, blood serum, urine, and an esophagus explant-based in vivo colony-forming assay were used from oesophageal carcinoma patients. These patients underwent three fractions of high dose rate (HDR) intraluminal brachytherapy (ILBT).

Results: Human keratinocyte reporters exposed to blood sera taken after the third fraction of brachytherapy had a significant increase in cloning efficiency compared to baseline samples (p < 0.001). Such results may suggest an induced radioresistance response in bystander cells. The data also revealed a clear inverse dose-rate effect during late treatment fractions for the blood sera data only. Patient characteristics such as gender had no statistically significant effect (p > 0.05). Large variability was observed among the patients’ tissue samples, these colony-forming assays showed no significant changes throughout fractionated brachytherapy (p > 0.05).

Conclusion: Large inter-patient variability was found in the urine and tissue based assays, so these techniques were discontinued. However, the simple blood-based assay had much less variability. This technique may have future applications as a biological dosimeter to predict treatment outcome and assess non-targeted radiation effects.

Acknowledgements

We wish to thank Varian International B.V. for supporting a portion of this work. We are grateful for the Hamilton Health Sciences JCC brachytherapy staff for assisting in sample collection. We acknowledge and thank all the patients who participated in this study. A special thanks to the Molecular Medicine laboratory at McMaster University and the JCC Clinical trials laboratory for centrifuge usage. All authors have read and approved this manuscript for submission, and have also read the journal's authorship agreement.

Declaration of interest: The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.