Case Report: MR-LINAC-guided adaptive radiotherapy for gastric cancer

Yajun Song; Yun Zhang; Huadong Wang; Mengyu Zhao; Fada Guan; Zhenjiang Li; Jinbo Yue

doi:10.3389/fonc.2023.1159197

Case Report: MR-LINAC-guided adaptive radiotherapy for gastric cancer

Front Oncol. 2023 Sep 8:13:1159197. doi: 10.3389/fonc.2023.1159197. eCollection 2023.

Authors

Yajun Song^{1

2}, Yun Zhang², Huadong Wang^{1

3}, Mengyu Zhao⁴, Fada Guan⁵, Zhenjiang Li³, Jinbo Yue²

Affiliations

¹ Department of Graduate, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.
² Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.
³ Department of Radiation Physics, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China.
⁴ Cheeloo College of Medicine, Shandong University, Jinan, China.
⁵ Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, United States.

Abstract

Background: The stomach is one of the most deformable organs. Its shape can be easily affected by breathing movements, and daily diet, and it also varies when the body position is different. The susceptibility of stomach has made it challenging to treat gastric cancer using the conventional image-guided radiotherapy, i.e., the techniques based on kilovoltage X-ray imaging. The magnetic resonance imaging guided radiotherapy (MRgRT) is usually implemented using a hybrid system MR-LINAC. It is feasible to implement adaptive radiotherapy using MR-LINAC for deformable organs such as stomach. In this case report, we present our clinical experience to treat a gastric cancer patient using MR-LINAC.

Case description: The patient is a 58-year-old male who started having black stools with no apparent cause a year ago. Gastroscopy result showed pancreatic cancer, pathology: adenocarcinoma on gastric cancer biopsy, adenocarcinoma on gastric body minor curvature biopsy. The patient was diagnosed with gastric cancer (adenocarcinoma, cTxN+M1, stage IV, HER-2 positive). The patient was treated in 25 fractions with radiotherapy using MR-LINAC with online adaptive treatment plans daily. The target area in daily MR images varied considerably when compared with the target area on the CT simulation images. During the course of treatment, there have even been instances where the planned target area where the patient received radiotherapy did not cover the lesion of the day.

Conclusion: Online adaptive MRgRT can be a meaningful innovation for treating malignancies in the upper abdomen. The results in the current study are promising and are indicative for further optimizing online adaptive MRgRT in patients with inoperable tumors of the upper abdomen.

Keywords: MR-LINAC; adaptive planning; gastric cancer; magnetic resonance guided radiation therapy; online adaptive radiation therapy; radiotherapy.

Publication types

Case Reports

Grants and funding

This work was supported by the following grants: National Natural Science Foundation of China (Grant No. 81871895;82272753), Young Taishan Scholars and Academic Promotion Program of Shandong First Medical University (Grant No. 2019RC003).