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

• Published in: Anticancer research Vol. 37; no. 10; p. 5673
• Main Authors: Shiba, Shintaro, Saitoh, Jun-Ichi, Irie, Daisuke, Shirai, Katsuyuki, Abe, Takanori, Kubota, Yoshiki, Sakai, Makoto, Okada, Ryosuke, Ohno, Tatsuya, Nakano, Takashi
• Format: Journal Article
• Language: English
• Published: Greece 01.10.2017
• Subjects: Area Under Curve; Carcinoma, Non-Small-Cell Lung - diagnostic imaging; Carcinoma, Non-Small-Cell Lung - pathology; Carcinoma, Non-Small-Cell Lung - radiotherapy; Fiducial Markers; Heavy Ion Radiotherapy - adverse effects; Heavy Ion Radiotherapy - instrumentation; Heavy Ion Radiotherapy - methods; Humans; Lung Neoplasms - diagnostic imaging; Lung Neoplasms - pathology; Lung Neoplasms - radiotherapy; Neoplasm Staging; Patient Positioning - adverse effects; Predictive Value of Tests; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Retrospective Studies; ROC Curve; Tomography, X-Ray Computed; Treatment Outcome; Tumor Burden; lung cancer; Carbon-ion radiotherapy; fiducial marker matching
• ISSN: 1791-7530; 1791-7530
• DOI: 10.21873/anticanres.12003

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