PURPOSE: The aim of the study was to estimate interfractional deviations in @entity1 and prostate position, the impact of the frequency of online verification on the treatment margins, and to assess acute radiation reactions of high-dose external beam image-guided intensity-modulated radiotherapy (IG-IMRT) of @entity263 . @entity1 AND METHODS: IG-IMRT was performed by daily online verification of implanted fiducial prostate markers using a megavoltage electronic portal imaging device (EPID). A total of 1011  image-guided treatment fractions from 23  consecutive unselected @entity263 @entity1 were analyzed. The median total dose was 79.2  Gy (range 77.4-81.0  Gy). Acute radiation reactions were assessed weekly during radiotherapy using the Common Terminology Criteria for Adverse Events (CTCAE) v.4.03. RESULTS: A relevant combined @entity1 set-up and prostate motion population random error of 4-5  mm was observed. Compared to daily IGRT, image guidance every other day required an expansion of the CTV- @entity343 (clinical target volume-planning target volume) margin of 8.1, 6.6, and 4.1  mm in the longitudinal, vertical, and lateral directions, thereby, increasing the @entity343 by approximately 30-40   %. No grade 3 or 4 acute radiation reactions were observed with daily IG-IMRT. CONCLUSION: A high dose with surprisingly low acute @entity137 can be applied with daily IG-IMRT using implanted fiducial prostate markers. Daily image guidance is clearly superior to image guidance every other fraction concerning adequate target coverage with minimal margins.

Image-guided intensity-modulated radiotherapy of @entity263 : Analysis of interfractional errors and acute XXXX .

@entity1 :: ('9606', 'Species') :: ['patients', 'patient', 'PATIENTS'] @entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity'] @entity263 :: ('MESH:D011471', 'Disease') :: ['localized prostate cancer', 'prostate cancer'] @entity343 :: ('187978', 'Species') :: ['PTV']
@entity137 :: (MESH:D064420,Disease) :: ['toxicity']
