Table 1. Patient characteristics.
| Patient characteristics at initial diagnosis | Total | Only TKI | Concomitant TKI and bisphosphonates | χ2 or log-rank |
|---|---|---|---|---|
| Number of patients | 76 | 27 | 49 | |
| Mean age (years) | 59 | 61 | 58 | |
| Male | 71% (54/76) | 70% (19/27) | 71% (35/49) | |
| No nephrectomy | 9% (7/76) | 11% (3/27) | 8% (4/49) | P=0.67 |
| M1 (synchronous metastases) | 55% (42/76) | 48% (13/27) | 59% (29/49) | P=0.35 |
| Interval between diagnosis initial tumour and diagnosis metastases (median) | 5.0 months | 0.0 months | P=0.49 | |
| Interval between diagnosis metastases and start TKI (median) | 5.0 months | 8.5 months | P=0.23 | |
| Interval between diagnosis initial tumour and start TKI (median) | 23.0 months | 17.0 months | P=0.42 | |
| Fuhrman | ||||
| Grade 1–3 | 58% (42/72) | 65% (17/26) | 54% (25/46) | P=0.36 |
| Grade 4 | 42% (30/72) | 35% (9/26) | 46% (21/46) | |
| Histology | ||||
| Clear cell | 88% (67/76) | 85% (23/27) | 90% (44/49) | |
| Non-clear cell | 12% (9/76) | 15% (4/27) | 10% (5/49) | |
| Sarcomatoid features | 20% (15/76) | 11% (3/27) | 24% (12/49) | P=0.16 |
| Patient characteristics at start of TKI | ||||
| ECOG PS>0 | 58% (44/76) | 67% (18/27) | 53% (26/49) | P=0.34 |
| Neutrophils >4500 mm−3 | 58% (44/76) | 52% (14/27) | 61% (30/49) | P=0.43 |
| Platelets >400 000 mm−3 | 17% (13/76) | 15% (4/27) | 18% (9/49) | |
| Haemoglobin <11.5 g dl−1 (women) or <13 g dl−1 (men) | 66% (51/76) | 59% (16/27) | 71% (35/49) | P=0.28 |
| LDH>1.5x ULN | 5% (4/76) | 4% (1/27) | 6% (3/49) | |
| Corrected calcium>10 mg dl−1 | 13% (10/76) | 7% (2/27) | 16% (8/49) | P=0.27 |
| Interval between nephrectomy and systemic treatment <12 months | 54% (41/76) | 41% (11/27) | 61% (30/49) | P=0.086 |
| Immunotherapy before targeted therapy | 43% (33/76) | 44% (12/27) | 43% (21/49) | |
| Site of metastasis | ||||
| Lung | 79% (60/76) | 85% (23/27) | 76% (37/49) | P=0.32 |
| Liver | 21% (16/76) | 30% (8/27) | 16% (8/49) | P=0.17 |
| Bone | 100% (76/76) | 100% (27/27) | 100% (49/49) | |
| Brain | 9% (7/76) | 4% (1/27) | 12% (6/49) | P=0.22 |
| Mean number of sites of metastases | 3.64 | 4.07 | 3.39 | |
| Mean number of bone metastases | 3.20 | 2.29 | 4.04 | |
| Targeted treatment | ||||
| Sunitinib | 75% (57/76) | 63% (17/27) | 82% (40/49) | P=0.072 |
| Sorafenib | 25% (19/76) | 37% (10/27) | 18% (9/49) | |
| MSKCC prognosis | ||||
| Favourable | 8% (6/76) | 7% (2/27) | 8% (4/49) | |
| Intermediate | 57% (43/76) | 59% (16/27) | 55% (27/49) | |
| Poor | 36% (27/76) | 33% (9/27) | 37% (18/49) | |
Abbreviations: ECOG PS=Eastern Cooperative Oncology Group performance status; LDH=lactate dehydrogenase; MSKCC=Memorial Sloan-Kettering Cancer Center; TKI=tyrosine kinase inhibitor; ULN=upper limit of normal.
Note: When differences in frequency of markers were found, a statistical comparison was performed with a χ2-test for percentages or a log-rank for comparison of time-to-events.
Note: The Memorial Sloan-Kettering Cancer Center criteria stratify patients receiving immunotherapy into three risk groups (favourable, intermediate and poor prognosis) according to five factors adversely associated with OS: time from initial diagnosis to start of systemic therapy, elevated baseline lactate dehydrogenase (LDH) and corrected calcium, low-baseline haemoglobin, and low Eastern Cooperative Oncology Group performance status.