TY - JOUR

T1 - MR-guided stereotactic radiotherapy of infra-diaphragmatic oligometastases

T2 - Evaluation of toxicity and dosimetric parameters

AU - van Overeem Felter, Mette

AU - Møller, Pia Krause

AU - Josipovic, Mirjana

AU - Bekke, Susanne Nørring

AU - Bernchou, Uffe

AU - Serup-Hansen, Eva

AU - Madsen, Kasper

AU - Parikh, Parag J.

AU - Kim, Joshua

AU - Geertsen, Poul

AU - Behrens, Claus P.

AU - Vogelius, Ivan R.

AU - Pøhl, Mette

AU - Schytte, Tine

AU - Persson, Gitte Fredberg

N1 - Publisher Copyright: © 2024 Elsevier B.V.

PY - 2024

Y1 - 2024

N2 - Background and purpose: The SOFT trial is a prospective, multicenter, phase 2 trial investigating magnetic resonance (MR)-guided stereotactic ablative radiotherapy (SABR) for abdominal, soft tissue metastases in patients with oligometastatic disease (OMD) (clinicaltrials.gov ID NCT04407897). We present the primary endpoint analysis of 1-year treatment-related toxicity (TRAE). Materials and methods: Patients with up to five oligometastases from non-hematological cancers were eligible for inclusion. A risk-adapted strategy prioritized fixed organs at risk (OAR) constraints over target coverage. Fractionation schemes were 45–67.5 Gy in 3–8 fractions. The primary endpoint was grade ≥ 4 TRAE within 12 months post-SABR. The association between the risk of gastrointestinal (GI) toxicity and clinical and dosimetric parameters was tested using a normal tissue complication probability model. Results: We included 121 patients with 147 oligometastatic targets, mainly located in the liver (41 %), lymph nodes (35 %), or adrenal glands (14 %). Nearly half of all targets (48 %, n = 71) were within 10 mm of a radiosensitive OAR. No grade 4 or 5 TRAEs, 3.5 % grade 3 TRAEs, and 43.7 % grade 2 TRAEs were reported within the first year of follow-up. We found a significant association between grade ≥ 2 GI toxicity and the parameters GI OAR D0.1cc, D1cc, and D20cc. Conclusion: In this phase II study of MR-guided SABR of oligometastases in the infra-diaphragmatic region, we found a low incidence of toxicity despite half of the lesions being within 10 mm of a radiosensitive OAR. GI OAR D0.1cc, D1cc, and D20cc were associated with grade ≥ 2 GI toxicity.

AB - Background and purpose: The SOFT trial is a prospective, multicenter, phase 2 trial investigating magnetic resonance (MR)-guided stereotactic ablative radiotherapy (SABR) for abdominal, soft tissue metastases in patients with oligometastatic disease (OMD) (clinicaltrials.gov ID NCT04407897). We present the primary endpoint analysis of 1-year treatment-related toxicity (TRAE). Materials and methods: Patients with up to five oligometastases from non-hematological cancers were eligible for inclusion. A risk-adapted strategy prioritized fixed organs at risk (OAR) constraints over target coverage. Fractionation schemes were 45–67.5 Gy in 3–8 fractions. The primary endpoint was grade ≥ 4 TRAE within 12 months post-SABR. The association between the risk of gastrointestinal (GI) toxicity and clinical and dosimetric parameters was tested using a normal tissue complication probability model. Results: We included 121 patients with 147 oligometastatic targets, mainly located in the liver (41 %), lymph nodes (35 %), or adrenal glands (14 %). Nearly half of all targets (48 %, n = 71) were within 10 mm of a radiosensitive OAR. No grade 4 or 5 TRAEs, 3.5 % grade 3 TRAEs, and 43.7 % grade 2 TRAEs were reported within the first year of follow-up. We found a significant association between grade ≥ 2 GI toxicity and the parameters GI OAR D0.1cc, D1cc, and D20cc. Conclusion: In this phase II study of MR-guided SABR of oligometastases in the infra-diaphragmatic region, we found a low incidence of toxicity despite half of the lesions being within 10 mm of a radiosensitive OAR. GI OAR D0.1cc, D1cc, and D20cc were associated with grade ≥ 2 GI toxicity.

KW - MR-linac

KW - Oligometastatic disease

KW - Risk-adaption

KW - SABR

KW - SBRT

KW - Stereotactic ablative radiotherapy

KW - Stereotactic body radiotherapy

KW - Toxicity

U2 - 10.1016/j.radonc.2024.110090

DO - 10.1016/j.radonc.2024.110090

M3 - Journal article

C2 - 38224916

AN - SCOPUS:85184777517

VL - 192

JO - Radiotherapy & Oncology

JF - Radiotherapy & Oncology

SN - 0167-8140

M1 - 110090

ER -