Tracking target position variability using intraprostatic fiducial markers and electronic portal imaging in prostate cancer radiotherapy

摘要

Modern radiotherapy has achieved substantial improvement in tumour control and toxicity rates by escalating the total dose to the target volume while sparing surrounding normal tissues. It has therefore become necessary to precisely track tumour position in order to minimise geometrical uncertainties due to setup errors and organ motion. We conducted this prospective evaluation of prostate cancer patients treated with image-guided conformal radiation therapy at our institution. We implanted three fiducial markers (gold seeds) within the prostatic gland in order to quantify daily target displacements and to generate specific margins around the clinical target volume (CTV) to create an appropriate planned target volume (PTV).