Potential Pitfalls of a Fiducial Marker-matching Technique in Carbon-ion Radiotherapy for Lung Cancer.

Abstract

BACKGROUND/AIM:

To analyze the accuracy of patient positioning and dose distribution quality using a fiducial marker-matching technique in carbon-ion radiotherapy (C-ion RT) for stage I lung cancer.

PATIENTS AND METHODS:

Thirteen patients with 26 fiducial markers and 104 radiation fields were examined. Change in the fiducial marker position coordinates from the gross tumor volume center (Δm), and change in the water-equivalent path length of the chest wall (ΔWEL) were measured in each radiation field. Criterion for an acceptable change in dose distribution was defined as the percentage of D95 (%D95) at gross tumor volume greater than 90% of the prescribed dose.

RESULTS:

Thirteen radiation fields (12.5%) were classified as unacceptable. Δm and ΔWEL had significant negative correlations with %D95 and thus were significant factors related to unacceptable irradiation fields.

CONCLUSION:

Patient positioning using a fiducial marker-matching technique resulted in 12.5% of radiation fields demonstrating unacceptable degradation due to Δm and ΔWEL.

• Authors: Shintaro Shiba, Jun-Ichi Saitoh, Daisuke Irie, Katsuyuki Shirai, Takanori Abe, Yoshiki Kubota, Makoto Sakai, Ryosuke Okada, Tatsuya Ohno, Takashi Nakano
• Journal: Anticancer research (Anticancer Res) Vol. 37 Issue 10 Pg. 5673-5680 (10 2017) ISSN: 1791-7530 [Electronic] Greece
• PMID: 28982885 (Publication Type: Journal Article)
• Copyright: Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Topics

• Area Under Curve
• Carcinoma, Non-Small-Cell Lung (diagnostic imaging, pathology, radiotherapy)
• Fiducial Markers
• Heavy Ion Radiotherapy (adverse effects, instrumentation, methods)
• Humans
• Lung Neoplasms (diagnostic imaging, pathology, radiotherapy)
• Neoplasm Staging
• Patient Positioning (adverse effects)
• Predictive Value of Tests
• ROC Curve
• Radiotherapy Dosage
• Radiotherapy Planning, Computer-Assisted
• Retrospective Studies
• Tomography, X-Ray Computed
• Treatment Outcome
• Tumor Burden