Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2009 Jul 1;74(3):884-91.
doi: 10.1016/j.ijrobp.2009.02.003. Epub 2009 Apr 22.

Characterization of pancreatic tumor motion using cine MRI: surrogates for tumor position should be used with caution

Mary Feng  1 , James M Balter, Daniel Normolle, Saroja Adusumilli, Yue Cao, Thomas L Chenevert, Edgar Ben-Josef
Affiliations

Characterization of pancreatic tumor motion using cine MRI: surrogates for tumor position should be used with caution

Mary Feng et al. Int J Radiat Oncol Biol Phys. .

Abstract

Purpose: Our current understanding of intrafraction pancreatic tumor motion due to respiration is limited. In this study, we characterized pancreatic tumor motion and evaluated the application of several radiotherapy motion management strategies.

Methods and materials: Seventeen patients with unresectable pancreatic cancer were enrolled in a prospective internal review board-approved study and imaged during shallow free-breathing using cine MRI on a 3T scanner. Tumor borders were agreed on by a radiation oncologist and an abdominal MRI radiologist. Tumor motion and correlation with the potential surrogates of the diaphragm and abdominal wall were assessed. These data were also used to evaluate planning target volume margin construction, respiratory gating, and four-dimensional treatment planning for pancreatic tumors.

Results: Tumor borders moved much more than expected. To provide 99% geometric coverage, margins of 20 mm inferiorly, 10 mm anteriorly, 7 mm superiorly, and 4 mm posteriorly are required. Tumor position correlated poorly with diaphragm and abdominal wall position, with patient-level Pearson correlation coefficients of -0.18-0.43. Sensitivity and specificity of gating with these surrogates was also poor, at 53%-68%, with overall error of 35%-38%, suggesting that the tumor may be underdosed and normal tissues overdosed.

Conclusions: Motion of pancreatic tumor borders is highly variable between patients and larger than expected. There is substantial deformation with breathing, and tumor border position does not correlate well with abdominal wall or diaphragmatic position. Current motion management strategies may not account fully for tumor motion and should be used with caution.

PubMed Disclaimer

Conflict of interest statement

Conflicts of Interest Notification. Actual or potential conflicts of interest do not exist.

Figures

Figure 1
Figure 1
In panel a, the tumor is contoured on a coronal image. The superior and inferior tumor borders are marked, as is the diaphragm. In panel b, in addition to the tumor contour and superior and inferior borders, the abdominal wall is marked.
Figure 2
Figure 2
Cumulative histogram of range of tumor border motion.
Figure 3
Figure 3
Tracing of superior (gray) and inferior (black) tumor border positions over time in a typical patient.
Figure 4
Figure 4
Difference between superior and inferior tumor borders over time. Differences up to 5mm suggest tumor deformation.
Figure 5
Figure 5
Figure 5a and b. Poor correlation between tumor borders and the diaphragm.
Figure 6
Figure 6
Figure 6a and b. Poor correlation between tumor borders and the abdominal wall.
Figure 7
Figure 7
Temporal distribution of tumor border position.
See this image and copyright information in PMC

References

    1. Treatment of locally unresectable carcinoma of the pancreas: comparison of combined-modality therapy (chemotherapy plus radiotherapy) to chemotherapy alone. Gastrointestinal Tumor Study Group. J Natl Cancer Inst. 1988;80:751–755. - PubMed
    1. Ben-Josef E, Shields AF, Vaishampayan U, et al. Intensity-modulated radiotherapy (IMRT) and concurrent capecitabine for pancreatic cancer. Int J Radiat Oncol Biol Phys. 2004;59:454–459. - PubMed
    1. Murphy MJ, Martin D, Whyte R, et al. The effectiveness of breath-holding to stabilize lung and pancreas tumors during radiosurgery. Int J Radiat Oncol Biol Phys. 2002;53:475–482. - PubMed
    1. Gierga DP, Chen GT, Kung JH, et al. Quantification of respiration-induced abdominal tumor motion and its impact on IMRT dose distributions. Int J Radiat Oncol Biol Phys. 2004;58:1584–1595. - PubMed
    1. Bussels B, Goethals L, Feron M, et al. Respiration-induced movement of the upper abdominal organs: a pitfall for the three-dimensional conformal radiation treatment of pancreatic cancer. Radiother Oncol. 2003;68:69–74. - PubMed

Publication types

MeSH terms