Visualization of tumor hypoxia and re-oxygenation after stereotactic body radiation therapy in early peripheral lung cancer: A prospective study.

Abstract

BACKGROUND AND PURPOSE:

In this study, fluoromisonidazole positron emission tomography (F-MISO PET/CT) was used to evaluate tumor hypoxia and re-oxygenation in patients with lung tumors treated with stereotactic body radiation therapy (SBRT).

MATERIALS AND METHODS:

Patients with T1-2 N0 lung cancer were included in this study. The prescribed dose was 48-52 Gy in four fractions. F-MISO PET/CT was performed twice, before SBRT and 1-3 days after the first irradiation. The maximum standardized uptake value (SUVmax) and tumor/muscle ratio (TMR) were evaluated as indicators of hypoxia. The threshold for hypoxia was defined as a TMR of 1.30 or more.

RESULTS:

Between 2016 and 2021, 15 patients were included. Pre-treatment tumor hypoxia was observed in nine tumors (60 %). TMR in all six tumors without pre-treatment hypoxia rose after single high-dose irradiation. In contrast, TMR in six of nine tumors with pre-treatment hypoxia dropped after irradiation, suggesting re-oxygenation. Although no local recurrence was noted, regional and/or distant relapses were seen in four patients (27 %). Of these, three had tumors with abnormal F-MISO uptake. The remaining patient had a tumor without signs of hypoxia on pre-treatment PET/CT. The 2-year progression free survival of patients with tumors with and without pre-treatment hypoxia were 30 % and 63 %, respectively (p = 0.319).

CONCLUSION:

Tumor hypoxia reduced after single high-dose irradiation. Tumor with F-MISO uptake seems to be an unfavorable prognostic factor in lung SBRT.

• Authors: Masahiro Inada, Yasumasa Nishimura, Kohei Hanaoka, Kiyoshi Nakamatsu, Hiroshi Doi, Takuya Uehara, Mikihito Komanishi, Kazunari Ishii, Hayato Kaida, Makoto Hosono
• Journal: Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology (Radiother Oncol) Vol. 180 Pg. 109491 (03 2023) ISSN: 1879-0887 [Electronic] Ireland
• PMID: 36706956 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.

Chemical References

• fluoromisonidazole
• Radiation-Sensitizing Agents

Topics

• Humans
• Lung Neoplasms (diagnostic imaging, pathology, radiotherapy)
• Lung (pathology)
• Radiosurgery
• Radiation Dosage
• Tumor Hypoxia (radiation effects)
• Positron-Emission Tomography
• Positron Emission Tomography Computed Tomography
• Radiation-Sensitizing Agents
• Prospective Studies
• Male
• Female
• Middle Aged
• Aged
• Aged, 80 and over