Respiratory movement of upper abdominal organs and its effect on radiotherapy planning in pancreatic cancer1

Gwynne, Sarah, Wills, Lauren, Joseph, Giannina, John, G., Staffurth, John Nicholas ORCID: https://orcid.org/0000-0002-7834-3172, Hurt, Chris Nicholas ORCID: https://orcid.org/0000-0003-1206-8355 and Mukherjee, Saptarshi 2009. Respiratory movement of upper abdominal organs and its effect on radiotherapy planning in pancreatic cancer1. Clinical Oncology 21 (9) , pp. 713-719. 10.1016/j.clon.2009.07.015

Full text not available from this repository.

Abstract

Aims Radiotherapy for pancreatic cancer is complicated by the frequent overlapping of the planning target volume (PTV) and the organ at risk (OAR), limiting the dose that can be safely delivered to the tumour. Individualising the margins applied to the clinical target volume (CTV) may reduce OAR irradiation without increasing the risk of geographical miss. We quantified the movement of the pancreas with respiration and evaluated whether individualised margins based on this motion reduced the dose to OARs. Materials and methods Planning computed tomography scans were acquired in quiet breathing, held expiration and held inspiration. Organ motion was evaluated from displacement of a reproducible point within the pancreas in all directions. Two sets of plans (standard plan: Pstan; individualised plan incorporating movement data: Pind) were generated for each patient. The PTV and doses to OARs were evaluated for both sets of plans. Results The mean (standard deviation) movement of the pancreas in the superior–inferior, lateral and anterior–posterior directions were 15.3 mm (4.3), 5.2 mm (3.5) and 9.7 mm (6.1), respectively. The use of individualised margins reduced the mean PTV volume by 33.5% (9.8) (P = 0.0051). The proportional reductions in the percentage of kidney receiving >10 Gy, small bowel >45 Gy and liver >30 Gy were 63.7% (P = 0.0051), 29.3% (P = 0.0125) and 29.2% (P = 0.0107), respectively. For the same level of OAR constraints, individualised margins allowed dose escalation in six of the 10 patients to a mean dose of 63.2 Gy. Conclusions The present study shows a simple way of incorporating organ motion into the planning process and can be adopted by any centre without major strain on healthcare resources. The use of individualised margins reduced PTV volume and the dose to OARs. This may offer an opportunity for dose escalation to try and further improve local control.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Medicine
Subjects:	R Medicine > RC Internal medicine > RC0254 Neoplasms. Tumors. Oncology (including Cancer)
Uncontrolled Keywords:	individualised margins, pancreas, radiotherapy
Publisher:	Elsevier
ISSN:	0936-6555
Last Modified:	19 Oct 2022 10:24
URI:	https://orca.cardiff.ac.uk/id/eprint/24263

Citation Data

Cited 37 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item