Table 1.
Patients’ and treatments’ characteristics.
| Epidemiologic Characteristics | ||
|---|---|---|
| Age | Median 57 (34–86) | |
| Age subgroups | <40 years | 5 pts (8%) |
| Between 40–50 | 15 pts (25%) | |
| Between 51–70 | 28 pts (48%) | |
| >70 years | 11 pts (19%) | |
| Metastatic disease esordium | At diagnosis de novo | 13 pts (22%) |
| Distant relapse | 46 pts (78%) | |
| Subtype | Luminal A-like | 6 pts (10.2%) |
| Luminal B-like | 25 pts (42.3%) | |
| HER2+ | 24 pts (40.7%) | |
| Triple negative | 4 pts (6.8%) | |
| HER2+ population | HER2+/ER+ | 19 pts (76%) |
| HER2+/ER− | 6 pts (24%) | |
| Parenchymal site of oligoprogression | Brain | 19 pts (32.2%) |
| Bone | 23 pts (39%) | |
| Lung | 3 pts (5.1%) | |
| Nodes | 11 pts (18.6%) | |
| Primitive tumor | 1 pt (1.7%) | |
| Liver | 2 pts (3.4%) | |
| Systemic Therapies Characteristics | ||
| Systemic therapies ongoing | Anti-HER2 | 24 pts (40.7%) |
| CDK4/6i | 17 pts (28.8%) | |
| Endocrine therapies | 12 pts (20.4%) | |
| Chemotherapy | 6 pts (10.1%) | |
| Anti-HER2 therapies | Pertuzumab + Trastuzumab | 13 pts (54.1%) |
| T-DM1 | 6 pts (25%) | |
| Trastuzumab + Capacitabine | 2 pts (8.3%) | |
| Lapatinib + Capecitabine | 1 pt (4.2%) | |
| Trastuzumab + Vinorlbine | 1 pt (4.2%) | |
| Trastuzumab + Hormone therapy | 1 pt (4.2%) | |
| Number of systemic line ongoing | First | 39 pts (66.1%) |
| Second | 14 pts (23.7%) | |
| Third | 3 pts (5.1%) | |
| ≥Fourth | 3 pts (5.1%) | |
| Radiotherapy Characteristics | ||
| Radiotherapy techniques | 3D-CRT | 9 pts (15.6%) |
| IMRT | 1 pt (1.7%) | |
| VMAT/SBRT | 49 pts (83%) | |
| Bone RT treatments | SIB 40–30/20 Gy in 5 fr | 16 pts (69.5%) |
| 3D 30 Gy in 10 fr | 3 pts (13%) | |
| 3D 20 Gy in 5 fr | 3 pts (13%) | |
| Re-RT 16 Gy in 14 fr BID | 1 pts (4.5%) | |
| Brain RT treatments | SBRT 25.5 Gy in 3 fr | 10 pts (52.6%%) |
| WB-SIB 50/30 Gy in 10 fr | 7 pts (36.8%%) | |
| 3D WB 30 Gy in 10 fr | 1 pt (5.3%) | |
| Re-RT WB 16 Gy in 14 fr | 1 pt (5.3%) | |
| Lung RT treatments | SBRT 50 Gy in 5 fr | 3 pts (100%) |
| Nodes RT treatments | SBRT 50–35 Gy in 5 fr | 8 pts (72.7%) |
| SIB 57.5/50 Gy in 25 fr | 1 pt (9.1%) | |
| Re-RT 38 Gy in 30 fr | 1 pt (9.1%) | |
| 3D 28 Gy in 16 fr | 1 pt (9.1%) | |
| Liver RT treatments | SBRT 40 Gy in 5 fr | 1 pt (100%) |
| Primitive tumor RT treatments | SBRT 24 Gy in 3 fr | 1 pt (100%) |
| BED schedule analysis(For every analysis, patients were grouped according to dichotomous categories, resulting in more than one category) | RT with schedules ≥100 Gy for α/β = 10 |
9 pts |
| RT with schedules ≥100 Gy for α/β = 4 |
18 pts | |
| RT with schedules ≥75 Gy for α/β = 10 |
14 pts | |
| RT with schedules ≥75 Gy for α/β = 4 |
44 pts |