Addition of Metastasis-Directed Therapy to Standard of Care for Oligometastatic Solid Tumors: Primary Analysis of All Tumor-Histology Baskets of the Phase II Randomized EXTEND Trial - PubMed
2 days ago
- #Metastasis-directed therapy
- #Phase II trial
- #Oligometastatic cancer
- The EXTEND trial tested adding metastasis-directed therapy (MDT) to standard of care systemic therapy for oligometastatic solid tumors (1-5 metastases), showing improved progression-free survival overall.
- Overall, MDT plus standard of care significantly improved progression-free survival with a hazard ratio of 0.54, and this benefit persisted even when excluding prostate cancer baskets.
- Radiotherapy was the primary MDT method used (98% of metastases), and the trial identified histology-specific efficacy, with clear PFS benefits in pancreas, prostate, and 'Other' baskets, while breast and kidney results were inconclusive.
- Translational findings linked detectable circulating tumor DNA at enrollment to worse outcomes, but ctDNA clearance after three months correlated with better survival, and MDT induced systemic immune activation, suggesting a possible mechanism of benefit.