Stereotactic ablative radiotherapy for oligoprogressive solid tumours: A systematic review and meta-analysis

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Oligoprogressive metastases represent a clinical challenge in cancer management.
• Stereotactic ablative radiotherapy (SABR) is an emerging treatment modality for limited metastatic disease.

Purpose of the Study:

• To systematically review and meta-analyze the effectiveness of SABR in patients with oligoprogressive metastases.
• To pool clinical outcomes including progression-free survival (PFS) and overall survival (OS).

Main Methods:

• A comprehensive literature search was performed across five databases from January 2010 to January 2023.
• Included studies focused on patients with oligoprogressive disease treated with SABR to all lesions.
• Pooled analyses utilized a binary random effects model to assess outcomes.

Main Results:

• Twenty-five studies met eligibility criteria, with a surge in publications post-2017, predominantly in 2021-2022.
• The pooled 1-year PFS was 44% (95% CI: 34-53%), with notable variations across primary tumor sites.
• Specific 1-year PFS rates included: prostate (53%), kidney (49%), lung (62%), breast (13%), and mixed (30%).

Conclusions:

• There is a growing body of literature on SABR for oligoprogressive tumors, primarily retrospective studies in prostate and kidney cancers.
• Limited evidence exists for SABR's effectiveness in other cancer types.
• Standardized guidelines are recommended for consistent reporting and comparability in future research.