| Autor: |
Monica Lo Russo, Marcel Nachbar, Aisling Barry, Shree Bhide, Amy Chang, William Hall, Martijn Intven, Corrie Marijnen, Femke Peters, Bruce Minsky, Paul B. Romesser, Reith Sarkar, Alex Tan, Simon Boeke, Daniel Wegener, Sarah Butzer, Jessica Boldt, Sergios Gatidis, Konstantin Nikolaou, Daniela Thorwarth, Daniel Zips, Cihan Gani |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Clinical and Translational Radiation Oncology, Vol 38, Iss , Pp 1-5 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2405-6308 |
| DOI: |
10.1016/j.ctro.2022.09.002 |
| Popis: |
Background: Online adaptive MR-guided radiotherapy allows for the reduction of safety margins in dose escalated treatment of rectal tumors. With the use of smaller margins, precise tumor delineation becomes more critical. In the present study we investigated the impact of rectal ultrasound gel filling on interobserver variability in delineation of primary rectal tumor volumes. Methods: Six patients with locally advanced rectal cancer were scanned on a 1.5 T MRI-Linac without (MRI_e) and with application of 100 cc of ultrasound gel transanally (MRI_f). Eight international radiation oncologists expert in the treatment of gastrointestinal cancers delineated the gross tumor volume (GTV) on both MRI scans. MRI_f scans were provided to the participating centers after MRI_e scans had been returned. Interobserver variability was analyzed by either comparing the observers’ delineations with a reference delineation (approach 1) and by building all possible pairs between observers (approach 2). Dice Similarity Index (DICE) and 95 % Hausdorff-Distance (95 %HD) were calculated. Results: Rectal ultrasound gel filling was well tolerated by all patients. Overall, interobserver agreement was superior in MRI_f scans based on median DICE (0.81 vs 0.74, p |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
