Effectiveness of Stereotactic Ablative Radiotherapy for Systemic Therapy Respondents with Inoperable Pulmonary Oligometastases and Oligoprogression
Chin-Beng Ho,
Jo-Ting Tsai,
Chun-You Chen,
Her-Shyong Shiah,
Hsuan-Yu Chen,
Lai-Lei Ting,
Chia-Chun Kuo,
I-Chun Lai,
Hsin-Yi Lai,
Chi-Li Chung,
Kai-Ling Lee,
Huey-En Tzeng,
Kuen-Haur Lee,
Hsin-Lun Lee,
Shang-Wen Chen,
Jeng-Fong Chiou
Affiliations
Chin-Beng Ho
Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei Medical University, Taipei 110301, Taiwan
Jo-Ting Tsai
Department of Radiation Oncology, Taipei Medical University-Shuang Ho Hospital, New Taipei City 235041, Taiwan
Chun-You Chen
Taipei Cancer Center, Taipei Medical University, Taipei 110301, Taiwan
Her-Shyong Shiah
Division of Hematology and Oncology, Department of Internal Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231016, Taiwan
Hsuan-Yu Chen
Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei Medical University, Taipei 110301, Taiwan
Lai-Lei Ting
Department of Radiation Oncology, Taipei Medical University Hospital, Taipei 110301, Taiwan
Chia-Chun Kuo
Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei Medical University, Taipei 110301, Taiwan
I-Chun Lai
Department of Heavy Particles and Radiation Oncology, Taipei Veterans General Hospital, Taipei 112201, Taiwan
Hsin-Yi Lai
Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei 110301, Taiwan
Chi-Li Chung
Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University Hospital, Taipei Medical University, Taipei 110301, Taiwan
Kai-Ling Lee
Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University Hospital, Taipei Medical University, Taipei 110301, Taiwan
Huey-En Tzeng
Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110301, Taiwan
Kuen-Haur Lee
Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei Medical University, Taipei 110301, Taiwan
Hsin-Lun Lee
Department of Radiation Oncology, Taipei Medical University Hospital, Taipei 110301, Taiwan
Shang-Wen Chen
Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110301, Taiwan
Jeng-Fong Chiou
Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei Medical University, Taipei 110301, Taiwan
Stereotactic ablative radiotherapy (SABR) may improve survival in patients with inoperable pulmonary oligometastases. However, the impact of pulmonary oligometastatic status after systemic therapy on SABR outcomes remains unclear. Hence, we investigated the outcomes of SABR in 45 patients with 77 lung tumors and the prognostic value of pulmonary oligoprogression. Eligibility criteria were pulmonary oligometastases (defined as ≤5 metastatic lung tumors), controlled extrapulmonary disease (EPD) after front-line systemic therapy, SABR as primary local treatment for inoperable pulmonary metastases, and consecutive imaging follow-up. Oligometastatic lung tumor was classified into controlled or oligoprogressive status. Overall survival (OS), in-field progression-free survival (IFPFS), out-field progression-free survival (OFPFS), and prognostic variables were evaluated. With 21.8 months median follow-up, the median OS, IFPFS, and OFPFS were 28.3, not reached, and 6.5 months, respectively. Two-year OS, IFPFS, and OFPFS rates were 56.0%, 74.2%, and 17.3%, respectively. Oligoprogressive status (p = 0.003), disease-free interval p = 0.041), and biologically effective dose (BED10) p = 0.006) were independently associated with inferior OS. BED10 ≥ 100 Gy (p = 0.029) was independently correlated with longer IFPFS. Oligoprogressive status (p = 0.017) and EPD (p = 0.019) were significantly associated with inferior OFPFS. Grade ≥ 2 radiation pneumonitis occurred in four (8.9%) patients. Conclusively, SABR with BED10 ≥ 100 Gy could provide substantial in-field tumor control and longer OS for systemic therapy respondents with inoperable pulmonary oligometastases. Oligoprogressive lung tumors exhibited a higher risk of out-field treatment failure and shorter OS. Hence, systemic therapy should be tailored for patients with oligoprogression to reduce the risk of out-field treatment failure. However, in the absence of effective systemic therapy, SABR is a reasonable alternative to reduce resistant tumor burden.
