Colin S Hill1, Sarah Han-Oh2, Zhi Cheng2, Ken Kang-Hsin Wang2, Jeffrey J Meyer2, Joseph M Herman3, Amol K Narang2. 1. Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, 401 N. Broadway, Suite 1440, Baltimore, MD, 21231, USA. chill48@jhmi.edu. 2. Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, 401 N. Broadway, Suite 1440, Baltimore, MD, 21231, USA. 3. Radiation Medicine, Zucker School of Medicine At Hofstra/Northwell, Lake Success, USA.
Abstract
PURPOSE: Variation in target positioning represents a challenge to set-up reproducibility and reliability of dose delivery with stereotactic body radiation therapy (SBRT) for pancreatic adenocarcinoma (PDAC). While on-board imaging for fiducial matching allows for daily shifts to optimize target positioning, the magnitude of the shift as a result of inter- and intra-fraction variation may directly impact target coverage and dose to organs-at-risk. Herein, we characterize the variation patterns for PDAC patients treated at a high-volume institution with SBRT. METHODS: We reviewed 30 consecutive patients who received SBRT using active breathing coordination (ABC). Patients were aligned to bone and then subsequently shifted to fiducials. Inter-fraction and intra-fraction scans were reviewed to quantify the mean and maximum shift along each axis, and the shift magnitude. A linear regression model was conducted to investigate the relationship between the inter- and intra-fraction shifts. RESULTS: The mean inter-fraction shift in the LR, AP, and SI axes was 3.1 ± 1.8 mm, 2.9 ± 1.7 mm, and 3.5 ± 2.2 mm, respectively, and the mean vector shift was 6.4 ± 2.3 mm. The mean intra-fraction shift in the LR, AP, and SI directions were 2.0 ± 0.9 mm, 2.0 ± 1.3 mm, and 2.3 ± 1.4 mm, respectively, and the mean vector shift was 4.3 ± 1.8 mm. A linear regression model showed a significant relationship between the inter- and intra-fraction shift in the AP and SI axis and the shift magnitude. CONCLUSIONS: Clinically significant inter- and intra-fraction variation occurs during treatment of PDAC with SBRT even with a comprehensive motion management strategy that utilizes ABC. Future studies to investigate how these variations could lead to variation in the dose to the target and OAR should be investigated. Strategies to mitigate the dosimetric impact, including real time imaging and adaptive therapy, in select cases should be considered.
PURPOSE: Variation in target positioning represents a challenge to set-up reproducibility and reliability of dose delivery with stereotactic body radiation therapy (SBRT) for pancreatic adenocarcinoma (PDAC). While on-board imaging for fiducial matching allows for daily shifts to optimize target positioning, the magnitude of the shift as a result of inter- and intra-fraction variation may directly impact target coverage and dose to organs-at-risk. Herein, we characterize the variation patterns for PDAC patients treated at a high-volume institution with SBRT. METHODS: We reviewed 30 consecutive patients who received SBRT using active breathing coordination (ABC). Patients were aligned to bone and then subsequently shifted to fiducials. Inter-fraction and intra-fraction scans were reviewed to quantify the mean and maximum shift along each axis, and the shift magnitude. A linear regression model was conducted to investigate the relationship between the inter- and intra-fraction shifts. RESULTS: The mean inter-fraction shift in the LR, AP, and SI axes was 3.1 ± 1.8 mm, 2.9 ± 1.7 mm, and 3.5 ± 2.2 mm, respectively, and the mean vector shift was 6.4 ± 2.3 mm. The mean intra-fraction shift in the LR, AP, and SI directions were 2.0 ± 0.9 mm, 2.0 ± 1.3 mm, and 2.3 ± 1.4 mm, respectively, and the mean vector shift was 4.3 ± 1.8 mm. A linear regression model showed a significant relationship between the inter- and intra-fraction shift in the AP and SI axis and the shift magnitude. CONCLUSIONS: Clinically significant inter- and intra-fraction variation occurs during treatment of PDAC with SBRT even with a comprehensive motion management strategy that utilizes ABC. Future studies to investigate how these variations could lead to variation in the dose to the target and OAR should be investigated. Strategies to mitigate the dosimetric impact, including real time imaging and adaptive therapy, in select cases should be considered.
Authors: Thierry Conroy; Pascal Hammel; Mohamed Hebbar; Meher Ben Abdelghani; Alice C Wei; Jean-Luc Raoul; Laurence Choné; Eric Francois; Pascal Artru; James J Biagi; Thierry Lecomte; Eric Assenat; Roger Faroux; Marc Ychou; Julien Volet; Alain Sauvanet; Gilles Breysacher; Frédéric Di Fiore; Christine Cripps; Petr Kavan; Patrick Texereau; Karine Bouhier-Leporrier; Faiza Khemissa-Akouz; Jean-Louis Legoux; Béata Juzyna; Sophie Gourgou; Christopher J O'Callaghan; Claire Jouffroy-Zeller; Patrick Rat; David Malka; Florence Castan; Jean-Baptiste Bachet Journal: N Engl J Med Date: 2018-12-20 Impact factor: 91.245
Authors: Lola Rahib; Benjamin D Smith; Rhonda Aizenberg; Allison B Rosenzweig; Julie M Fleshman; Lynn M Matrisian Journal: Cancer Res Date: 2014-06-01 Impact factor: 12.701
Authors: Nancy El-Bared; Lorraine Portelance; Benjamin O Spieler; Deukwoo Kwon; Kyle R Padgett; Karen M Brown; Eric A Mellon Journal: Pract Radiat Oncol Date: 2018-08-25
Authors: Barbara Bussels; Laurence Goethals; Michel Feron; Didier Bielen; Steven Dymarkowski; Paul Suetens; Karin Haustermans Journal: Radiother Oncol Date: 2003-07 Impact factor: 6.280
Authors: Wensha Yang; Benedick A Fraass; Robert Reznik; Nicholas Nissen; Simon Lo; Laith H Jamil; Kapil Gupta; Howard Sandler; Richard Tuli Journal: Radiat Oncol Date: 2014-01-09 Impact factor: 3.481
Authors: Soumon Rudra; Naomi Jiang; Stephen A Rosenberg; Jeffrey R Olsen; Michael C Roach; Leping Wan; Lorraine Portelance; Eric A Mellon; Anna Bruynzeel; Frank Lagerwaard; Michael F Bassetti; Parag J Parikh; Percy P Lee Journal: Cancer Med Date: 2019-04-01 Impact factor: 4.452