Margins to compensate for respiratory-induced mismatches between lung tumor and fiducial marker positions using four-dimensional computed tomography.

ABSTRACT:

Background and purpose

Tumors and fiducial markers do not always exhibit synchronous motion across different respiratory phases, in a phenomenon called the target localization error (TLE). We determined the margin to compensate for the TLE using four-dimensional computed tomography (4D-CT).

Materials and methods

We analyzed data from 21 lung tumor patients with fiducial markers; 11 for TLE determination and 10 for validation. Shifted CT images were generated by aligning the centroids of the fiducial markers in the reference phase of 4D-CT with those in each respiratory phase, and the union of gross tumor volumes (GTVs) was determined ( G T V u n i o n s h i f t ). Conversely, variations in GTV centroids across the respiratory phases were calculated, and the 95th percentil

SUBMITTER: Matsumoto S 

PROVIDER: S-EPMC11871501 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature