Pancreatic tumors show large interfractional position variation. In addition, changes in gastrointestinal gas volumes and body contour take place over the course of radiation therapy. We aimed to quantify the effect of these anatomical changes on target dose coverage, for the clinically used fiducial marker-based patient position verification and, for comparison, also for simulated bony anatomy...

PurposeTo investigate the potential of an offline Adaptive Radiotherapy (ART) strategy, based on interfractional vagina motion (IVM) measured using fiducial markers (FM) during initial number fractions, CTV to PTV margins in post-operative gynecological patients.Materials and methodsIn 18 patients, treated post-operatively for tumors, systematic residual IVM was quantified after simulating ART ...

This study compared the dosimetric performance of (a) volumetric modulated arc therapy (VMAT) with standard optimization (STD) and (b) multi-criteria optimization (MCO) to (c) intensity modulated radiation therapy (IMRT) with MCO for hippocampal avoidance whole brain radiation therapy (HA-WBRT) in RayStation treatment planning system (TPS). Ten HA-WBRT patients previously treated with MCO-IMRT ...

Larynx may alternatively serve as a target or organs at risk (OAR) in head and neck cancer (HNC) image-guided radiotherapy (IGRT). The objective of this study was to estimate IGRT parameters required for larynx positional error independent of isocentric alignment and suggest population-based compensatory margins. Ten HNC patients receiving radiotherapy (RT) with daily CT on-rails imaging were a...

BACKGROUND Rectal cancer patients that show a pathological complete response (pCR) after neo-adjuvant chemo-radiotherapy, have better prognosis. To increase pCR rates several studies escalate the tumor irradiation dose. However, due to lacking tumor contrast on online imaging techniques, no direct tumor setup can be performed and large boost margins are needed to ensure tumor coverage. The purp...

Accurate definition of the lumpectomy cavity (LC) is essential for both partial breast and electron boost planning and delivery. The goal of this study is to evaluate CT, 3DUS and clips in the daily target localization of the LC. Twenty whole breast radiation patients, including 10 with clips, underwent two sets of treatment planning CTs (CT1, CT2) with co-registered 3DUS (US1, US2), separated ...

Received July 19, 2002; revision received September 16, 2002; accepted September 24, 2002. BACKGROUND. Randomized trials have shown improved local control with the use of a breast boost for patients given breast-conserving treatment for breast carcinoma. Although the use of a breast boost is routine practice, no standard technique has been established. The authors compared the commonly used cli...

BACKGROUND AND PURPOSE To investigate the definition of planning target volumes (PTVs) based on four-dimensional computed tomography (4DCT) compared with conventional PTV definition and PTV definition using asymmetrical margins for thoracic primary esophageal cancer. MATERIALS AND METHODS Forty-three patients with esophageal cancer underwent 3DCT and 4DCT simulation scans during free breathin...

This work is to show which is more relevant to cause local failures (LFs) due to patient setup uncertainty between the planning target volume (PTV) underdosage and the potential target underdosage subject to patient setup uncertainties in head and neck (H&N) cancer treated with volumetric-modulated arc therapy (VMAT). Thirteen LFs in 10 H&N patients treated by VMAT were analyzed. Measures have ...