Local control and patient reported outcomes after online MR guided stereotactic body radiotherapy of liver metastases

Introduction Stereotactic body radiotherapy (SBRT) is used to treat liver metastases with the intention of ablation. High local control rates were shown. Magnetic resonance imaging guided radiotherapy (MRgRT) provides the opportunity of a marker-less liver SBRT treatment due to the high soft tissue contrast. We report herein on one of the largest cohorts of patients treated with online MRgRT of liver metastases focusing on oncological outcome, toxicity, patient reported outcome measures (PROMs), quality of life. Material and methods Patients treated for liver metastases with online MR-guided SBRT at a 1,5 T MR-Linac (Unity, Elekta, Crawley, UK) between March 2019 and December 2021 were included in this prospective study. UK SABR guidelines were used for organs at risk constraints. Oncological endpoints such as survival parameters (overall survival, progression-free survival) and local control as well as patient reported acceptance and quality of life data (EORTC QLQ-C30 questionnaire) were assessed. For toxicity scoring the Common Toxicity Criteria Version 5 were used. Results A total of 51 patients with 74 metastases were treated with a median of five fractions. The median applied BED GTV D98 was 84,1 Gy. Median follow-up was 15 months. Local control of the irradiated liver metastasis after 12 months was 89,6%, local control of the liver was 40,3%. Overall survival (OS) after 12 months was 85.1%. Progression free survival (PFS) after 12 months was 22,4%. Local control of the irradiated liver lesion was 100% after three years when a BED ≥100 Gy was reached. The number of treated lesions did not impact local control neither of the treated or of the hepatic control. Patient acceptance of online MRgSBRT was high. There were no acute grade ≥ 3 toxicities. Quality of life data showed no significant difference comparing baseline and follow-up data. Conclusion Online MR guided radiotherapy is a noninvasive, well-tolerated and effective treatment for liver metastases. Further prospective trials with the goal to define patients who actually benefit most from an online adaptive workflow are currently ongoing.

[1]  T. Welzel,et al.  Magnetic resonance guided adaptive stereotactic body radiotherapy for lung tumors in ultracentral location: the MAGELLAN trial (ARO 2021-3) , 2022, Radiation oncology.

[2]  D. Low,et al.  Clinical outcomes of stereotactic magnetic resonance image‐guided adaptive radiotherapy for primary and metastatic tumors in the abdomen and pelvis , 2021, Cancer medicine.

[3]  B. van Triest,et al.  Development and results of a patient-reported treatment experience questionnaire on a 1.5 T MR-Linac , 2021, Clinical and translational radiation oncology.

[4]  C. K. Spindeldreier,et al.  Magnetic Resonance-Guided Stereotactic Body Radiotherapy of Liver Tumors: Initial Clinical Experience and Patient-Reported Outcomes , 2021, Frontiers in Oncology.

[5]  A. Kishan,et al.  Ablative Radiotherapy for Liver Tumors Using Stereotactic MRI-Guidance: A Prospective Phase I Trial. , 2021, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[6]  L. Dawson,et al.  MR-Guided Radiotherapy for Liver Malignancies , 2021, Frontiers in Oncology.

[7]  U. Abacıoğlu,et al.  Stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of liver metastases in oligometastatic patients: initial clinical experience , 2021, Radiation oncology journal.

[8]  D. Mönnich,et al.  Marker-less online MR-guided stereotactic body radiotherapy of liver metastases at a 1.5 T MR-Linac – Feasibility, workflow data and patient acceptance , 2020, Clinical and translational radiation oncology.

[9]  L. Collette,et al.  Characterisation and classification of oligometastatic disease: a European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer consensus recommendation. , 2020, The Lancet. Oncology.

[10]  L. Livi,et al.  Partial breast irradiation with the 1.5 T MR-Linac: First patient treatment and analysis of electron return and stream effects. , 2019, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[11]  Michael Lock,et al.  Stereotactic ablative radiotherapy versus standard of care palliative treatment in patients with oligometastatic cancers (SABR-COMET): a randomised, phase 2, open-label trial , 2019, The Lancet.

[12]  Sebastian Klüter,et al.  Technical design and concept of a 0.35 T MR-Linac , 2019, Clinical and translational radiation oncology.

[13]  Rob H.N. Tijssen,et al.  Adaptive radiotherapy: The Elekta Unity MR-linac concept , 2019, Clinical and translational radiation oncology.

[14]  M. Scorsetti,et al.  Phase II trial on SBRT for unresectable liver metastases: long-term outcome and prognostic factors of survival after 5 years of follow-up , 2018, Radiation oncology.

[15]  D. Mönnich,et al.  Comparison of treatment plans for a high-field MRI-linac and a conventional linac for esophageal cancer , 2018, Strahlentherapie und Onkologie.

[16]  H. Lyng,et al.  Potentials and challenges of diffusion-weighted magnetic resonance imaging in radiotherapy , 2018, Clinical and translational radiation oncology.

[17]  R. Semrau,et al.  The SBRT database initiative of the German Society for Radiation Oncology (DEGRO): patterns of care and outcome analysis of stereotactic body radiotherapy (SBRT) for liver oligometastases in 474 patients with 623 metastases , 2018, BMC Cancer.

[18]  W. Jackson,et al.  Comparison of Stereotactic Body Radiation Therapy and Radiofrequency Ablation in the Treatment of Intrahepatic Metastases. , 2017, International journal of radiation oncology, biology, physics.

[19]  G G Hanna,et al.  UK Consensus on Normal Tissue Dose Constraints for Stereotactic Radiotherapy. , 2018, Clinical oncology (Royal College of Radiologists (Great Britain)).

[20]  Andrew Jackson,et al.  Local Control After Stereotactic Body Radiation Therapy for Liver Tumors. , 2018, International journal of radiation oncology, biology, physics.

[21]  Jong Hoon Kim,et al.  Local Control Outcomes Using Stereotactic Body Radiation Therapy for Liver Metastases From Colorectal Cancer. , 2017, International journal of radiation oncology, biology, physics.

[22]  D. Edvardsson,et al.  Development and psychometric testing of an instrument to measure the patient’s experience of external radiotherapy: The Radiotherapy Experience Questionnaire (RTEQ) , 2017, Technical innovations & patient support in radiation oncology.

[23]  N. Kim,et al.  Current status and future perspectives on treatment of liver metastasis in colorectal cancer (Review). , 2017, Oncology reports.

[24]  J. Lee,et al.  Local Consolidative Therapy versus Maintenance Therapy/Observation for Patients with Oligometastatic Non-Small Cell Lung Cancer without Progression after Front-Line Systemic Therapy: Results of a Multi-Institutional Phase II Randomized Study , 2016, The Lancet. Oncology.

[25]  J F Fowler,et al.  21 years of biologically effective dose. , 2010, The British journal of radiology.

[26]  Anand Mahadevan,et al.  Stereotactic body radiation therapy for liver metastases. , 2009, European journal of cancer.

[27]  P. Levendag,et al.  Quality of life after stereotactic body radiation therapy for primary and metastatic liver tumors. , 2008, International journal of radiation oncology, biology, physics.

[28]  Robert G. Moore,et al.  Initial clinical experience , 1997 .

[29]  M. Anscher,et al.  Hepatic toxicity resulting from cancer treatment. , 1995, International journal of radiation oncology, biology, physics.