Study protocol of the LARK (TROG 17.03) clinical trial: a phase II trial investigating the dosimetric impact of Liver Ablative Radiotherapy using Kilovoltage intrafraction monitoring.
BACKGROUND
Stereotactic Ablative Body Radiotherapy (SABR) is a non-invasive treatment which allows delivery of an ablative radiation dose with high accuracy and precision. SABR is an established treatment for both primary and secondary liver malignancies, and technological advances have improved its efficacy and safety. Respiratory motion management to reduce tumour motion and image guidance to achieve targeting accuracy are crucial elements of liver SABR. This phase II multi-institutional TROG 17.03 study, Liver Ablative Radiotherapy using Kilovoltage intrafraction monitoring (LARK), aims to investigate and assess the dosimetric impact of the KIM real-time image guidance technology. KIM utilises standard linear accelerator equipment and therefore has the potential to be a widely available real-time image guidance technology for liver SABR.


METHODS
Forty-six patients with either hepatocellular carcinoma or oligometastatic disease to the liver suitable for and treated with SABR using Kilovoltage Intrafraction Monitoring (KIM) guidance will be included in the study. The dosimetric impact will be assessed by quantifying accumulated patient dose distribution with or without the KIM intervention. The patient treatment outcomes of local control, toxicity and quality of life will be measured.


DISCUSSION
Liver SABR is a highly effective treatment, but precise dose delivery is challenging due to organ motion. Currently, there is a lack of widely available options for performing real-time tumour localisation to assist with accurate delivery of liver SABR. This study will provide an assessment of the impact of KIM as a potential solution for real-time image guidance in liver SABR.


TRIAL REGISTRATION
This trial was registered on December 7th 2016 on ClinicalTrials.gov under the trial-ID NCT02984566 .
['Lee|Yoo Young Dominique|YYD|http://orcid.org/0000-0003-4325-349X', 'Nguyen|Doan Trang|DT|', 'Moodie|Trevor|T|', "O'Brien|Ricky|R|", 'McMaster|Anne|A|', 'Hickey|Andrew|A|', 'Pritchard|Nicole|N|', 'Poulsen|Per|P|', 'Tabaksblat|Elizaveta Mitkina|EM|', 'Weber|Britta|B|', 'Worm|Esben|E|', 'Pryor|David|D|', 'Chu|Julie|J|', 'Hardcastle|Nicholas|N|', 'Booth|Jeremy|J|', 'Gebski|Val|V|', 'Wang|Tim|T|', 'Keall|Paul|P|']
D001315:Australia D006528:Carcinoma, Hepatocellular D003718:Denmark D057918:Fiducial Markers D006801:Humans D008113:Liver Neoplasms D000075530:Organ Motion D011788:Quality of Life D016634:Radiosurgery D011879:Radiotherapy Dosage D011880:Radiotherapy Planning, Computer-Assisted D061089:Radiotherapy, Image-Guided D050397:Radiotherapy, Intensity-Modulated D012119:Respiration D016896:Treatment Outcome
Kilovoltage intrafraction monitoring Hepatocellular carcinoma LARK trial Liver Cancer Oligometastases Stereotactic radiotherapy