Table 2.
Choice of fractionation stratified by baseline characteristics (n = 118).
| Parameter | n | % <10 fractions (ITT) | % ≥10 fractions (ITT) | p-value |
|---|---|---|---|---|
| Triple negativea | 22 | 36% | 64% | |
| ER positive HER2 negativea | 68 | 35% | 65% | |
| ER negative HER2 positivea | 5 | 20% | 80% | |
| ER and HER2 positivea | 15 | 53% | 47% | 0.61b |
| Metastases at first diagnosisa | 17 | 35% | 65% | |
| Metachronous metastatic diseasea | 98 | 41% | 59% | 0.84 |
| Interval from met. disease to RT ≤6 moa | 56 | 27% | 73% | |
| Interval from met. disease to RT >6 moa | 59 | 53% | 47% | 0.007 |
| No extra-skeletal visceral metastases | 57 | 33% | 67% | |
| Visceral metastases | 61 | 46% | 54% | 0.28 |
| Liver metastases | 36 | 44% | 56% | |
| No liver metastases | 82 | 38% | 62% | 0.76 |
| Lung metastases | 38 | 58% | 42% | |
| No lung metastases | 80 | 31% | 69% | 0.017 |
| Pleural metastases/effusion | 19 | 64% | 36% | |
| No pleural metastases/effusion | 98 | 35% | 65% | 0.038 |
| Metastatic spinal cord compression | 10 | 20% | 80% | |
| No metastatic spinal cord compression | 108 | 42% | 58% | 0.27 |
| ECOG PS 0 | 32 | 28% | 72% | |
| ECOG PS 1 | 38 | 26% | 74% | |
| ECOG PS 2 | 32 | 50% | 50% | |
| ECOG PS 3–4 | 16 | 75% | 25% | 0.01b |
| Charlson comorbidity index 0a | 58 | 34% | 66% | |
| Charlson comorbidity index ≥1a | 53 | 42% | 58% | 0.46 |
| Age <65 years | 70 | 31% | 69% | |
| Age ≥65 years | 48 | 52% | 48% | 0.01 |
| Spinal target volume | 50 | 36% | 64% | |
| No spinal target volume | 68 | 43% | 57% | 0.45 |
| Only one target volume | 60 | 35% | 65% | |
| More than one target volume | 58 | 45% | 55% | 0.50 |
| Reirradiation | 18 | 61% | 39% | |
| No reirradiation | 100 | 36% | 64% | 0.07 |
| Serum albumin normala | 94 | 33% | 67% | |
| Serum albumin lowa | 18 | 72% | 28% | 0.007 |
| Serum LDH normala | 45 | 18% | 82% | |
| Serum LDH higha | 56 | 50% | 50% | 0.003 |
| Serum ALP normala | 47 | 30% | 70% | |
| Serum ALP higha | 58 | 43% | 57% | 0.21 |
| Serum CRP normala | 55 | 24% | 76% | |
| Serum CRP higha | 56 | 54% | 46% | 0.002 |
| Haemoglobin normala | 80 | 26% | 74% | |
| Haemoglobin lowa | 33 | 70% | 30% | 0.0001 |
| Received blood transfusion before RT | 9 | 67% | 33% | |
| No blood transfusion | 109 | 38% | 62% | 0.22 |
| Hypercalcemiaa | 10 | 30% | 70% | |
| No hypercalcemiaa | 101 | 40% | 60% | 0.36 |
| Non-opioid analgesicsa | 74 | 50% | 50% | |
| Opioid analgesicsa | 33 | 27% | 73% | 0.06 |
| Steroidsa | 31 | 39% | 61% | |
| No steroidsa | 72 | 42% | 58% | 0.81 |
a information not available in all patients
b p-value calculated over all strata
ER: oestrogen receptor; ITT: intention to treat; ECOG PS: Eastern Cooperative Oncology Group performance status; LDH: lactate dehydrogenase; ALP: alkaline phosphatase; CRP: C-reactive protein