Radiation-induced reductions in regional lung perfusion: 0.1-12 year data from a prospective clinical study.

Published

Journal Article

PURPOSE: To assess the time and regional dependence of radiation therapy (RT)-induced reductions in regional lung perfusion 0.1-12 years post-RT, as measured by single photon emission computed tomography (SPECT) lung perfusion. MATERIALS/METHODS: Between 1991 and 2005, 123 evaluable patients receiving RT for tumors in/around the thorax underwent SPECT lung perfusion scans before and serially post-RT (0.1-12 years). Registration of pre- and post-RT SPECT images with the treatment planning computed tomography, and hence the three-dimensional RT dose distribution, allowed changes in regional SPECT-defined perfusion to be related to regional RT dose. Post-RT follow-up scans were evaluated at multiple time points to determine the time course of RT-induced regional perfusion changes. Population dose response curves (DRC) for all patients at different time points, different regions, and subvolumes (e.g., whole lungs, cranial/caudal, ipsilateral/contralateral) were generated by combining data from multiple patients at similar follow-up times. Each DRC was fit to a linear model, and differences statistically analyzed. RESULTS: In the overall groups, dose-dependent reductions in perfusion were seen at each time post-RT. The slope of the DRC increased over time up to 18 months post-RT, and plateaued thereafter. Regional differences in DRCs were only observed between the ipsilateral and contralateral lungs, and appeared due to tumor-associated changes in regional perfusion. CONCLUSIONS: Thoracic RT causes dose-dependent reductions in regional lung perfusion that progress up to approximately 18 months post-RT and persists thereafter. Tumor shrinkage appears to confound the observed dose-response relations. There appears to be similar dose response for healthy parts of the lungs at different locations.

Full Text

Duke Authors

Cited Authors

  • Zhang, J; Ma, J; Zhou, S; Hubbs, JL; Wong, TZ; Folz, RJ; Evans, ES; Jaszczak, RJ; Clough, R; Marks, LB

Published Date

  • February 1, 2010

Published In

Volume / Issue

  • 76 / 2

Start / End Page

  • 425 - 432

PubMed ID

  • 19632063

Pubmed Central ID

  • 19632063

Electronic International Standard Serial Number (EISSN)

  • 1879-355X

Digital Object Identifier (DOI)

  • 10.1016/j.ijrobp.2009.02.005

Language

  • eng

Conference Location

  • United States