Background
Phase II single-arm prospective, N=42, oligometastatic (≤3 lesions) platinum-sensitive recurrent ovarian cancer after ≥2 prior platinum-based regimens. Treated with SBRT to all disease sites without concurrent systemic therapy.
Interventions and follow up
Treatment: SBRT to all sites; parenchymal lesions 24–45 Gy in 3–5 fractions, lymph nodes 30–45 Gy in 3–6 fractions; no concurrent systemic therapy
Primary endpoint: 12-month PFS
mFollow up: 24 month
Primary endpoint: 12-month PFS
mFollow up: 24 month
Results
12-month PFS: 52.4%
1-yr local control: 88.1%
Median time to next systemic therapy: 13 month
Median OS: Not reached at data cutoff
1-yr local control: 88.1%
Median time to next systemic therapy: 13 month
Median OS: Not reached at data cutoff
Adverse events
Acute grade 1–2: 29%
Acute grade 3–4: None
Late grade 3: 2 patients (4.8%)
Treatment-related deaths: None
Acute grade 3–4: None
Late grade 3: 2 patients (4.8%)
Treatment-related deaths: None
Conclusions
SBRT for oligometastatic platinum-sensitive recurrent ovarian cancer was feasible and safe with high local control (88.1%) and a median 13 months before next systemic therapy, supporting SBRT as a non-cytotoxic bridge strategy in selected patients.
Key Limitations
Single-arm phase II, no comparator (systemic therapy alone); small sample (N=42); selection bias inherent to oligometastatic definition (≤3 lesions); platinum-sensitive patients already favorable prognosis; no randomized OS data; heterogeneous recurrence sites and prior treatment.
Clinical Context
One of few prospective studies supporting SBRT for oligometastatic ovarian cancer; rationale is delaying systemic-therapy toxicity and enabling chemotherapy-free intervals. Increasingly integrated into multidisciplinary management of platinum-sensitive oligometastatic recurrence alongside PARP inhibitor strategies.