A prospective study of weekly intensity modulated radiation therapy plan adaptation for head and neck cancer: improved target coverage and organ at risk sparing.
Farhannah AlyA A MillerM G JamesonP E MetcalfePublished in: Australasian physical & engineering sciences in medicine (2018)
This prospective study of weekly CT scanning and plan adaption during H&N IMRT reports on the frequency of plan adaptations based on dosimetric differences between original and re-optimised IMRT plans. The volumetric and geometric change occurring in target volumes and salivary glands is also described. Ten H&N cancer patients underwent weekly planning CT imaging and re-optimisation of the IMRT plan if PTV or OAR coverage was unacceptable. Comparisons of PTV and parotid gland dosimetry between the original and adaptive plans were made. Parotid and submandibular gland volume changes and shift were calculated. Eight of ten patients required one or more plan adaptations, with 41% of adaptations occurring by fraction ten. Salivary glands reduced in volume, with a medial shift of the lateral border of the parotid gland and a superior shift of the submandibular gland. Change in PTV coverage did not correlate with weight loss or nutritional score. Inadequate PTV coverage, requiring plan adaptation, occurs early in the course of IMRT. A weekly Adaptive RT (ART) protocol results in significant improvement of PTV coverage. Implementation of a clinical ART protocol should include imaging and dose calculation within the first ten fractions.
Keyphrases
- affordable care act
- radiation therapy
- high resolution
- health insurance
- weight loss
- computed tomography
- randomized controlled trial
- end stage renal disease
- high intensity
- healthcare
- ejection fraction
- type diabetes
- chronic kidney disease
- newly diagnosed
- hiv infected
- primary care
- bariatric surgery
- magnetic resonance imaging
- prognostic factors
- minimally invasive
- locally advanced
- antiretroviral therapy
- radiation induced
- fluorescence imaging
- patient reported outcomes
- weight gain
- robot assisted