Table 1.
Characteristics of the study population
| No ipilimumab (n=37) | Ipilimumab (n=33) | P-value | |
|---|---|---|---|
| Type of RT | |||
| WBRT | 21 (56.8%) | 16 (48.5%) | 0.49 |
| SRS | 16 (43.2%) | 17 (51.5%) | |
| Years treated | 2005–2011 | 2009–2012 | Not applicable |
| Mean age (years) | 57.7 | 56.6 | 0.76 |
| Sex | |||
| Female | 17 (45.9%) | 13 (39.4%) | 0.58 |
| Male | 20 (54.1%) | 20 (60.6%) | |
| Type of melanoma | |||
| Cutaneous | 31 (83.8%) | 32 (97.0%) | 0.13 |
| Mucosal | 2 (5.4%) | 1 (3.0%) | |
| Unknown primary | 4 (10.8%) | 0 (0%) | |
| Number of brain metastases | |||
| >3 | 16 (43.2%) | 18 (54.6%) | 0.39 |
| 2 or 3 | 9 (24.3%) | 4 (12.1%) | |
| 1 | 12 (32.4%) | 11 (33.3%) | |
| Craniotomy prior to RT | |||
| Yes | 7 (18.9%) | 6 (18.2%) | 0.94 |
| No | 30 (81.1%) | 27 (81.8%) | |
| ECOG PS | |||
| 0 | 16 (45.7%) | 15 (53.6%) | 0.15 |
| 1 | 12 (34.3%) | 12 (42.9%) | |
| 2–31 | 7 (20.0%) | 1 (3.6%) | |
| Neurologic symptoms | |||
| Asymptomatic | 20 (54.0%) | 25 (75.8%) | 0.06 |
| Symptomatic | 17 (46.0%) | 8 (24.2%) | |
| RPA | |||
| Class I | 1 (2.7%) | 0 (0%) | 0.34 |
| Class II | 36 (97.3%) | 33 (100%) | |
| DS-GPA | |||
| 0–1 | 8 (24.2%) | 7 (25.0%) | 0.99 |
| 2 | 12 (36.4%) | 11 (39.3%) | |
| 3 | 9 (27.3%) | 7 (25.0%) | |
| 4 | 4 (12.1%) | 3 (10.7%) | |
| Serum LDH level | |||
| Normal | 20 (62.5%) | 18 (64.3%) | 0.89 |
| Elevated | 12 (37.5%) | 10 (35.7%) | |
| BRAF status | |||
| Mutated | 3 (25.0%) | 17 (51.5%) | 0.37 |
| Wild type | 1 (75.0%) | 16 (48.5%) | |
| Prior systemic therapy2 | |||
| Yes | 19 (51.4%) | 14 (42.4%) | 0.46 |
| No | 18 (48.6%) | 19 (57.6%) | |
| Subsequent systemic therapy3 | |||
| Yes | 22 (62.9%) | 18 (54.5%) | 0.49 |
| No | 13 (37.1%) | 15 (45.5%) | |
| Subsequent brain RT | |||
| Yes | 3 (8.1%) | 18 (54.6%) | <0.001 |
| No | 33 (89.2%) | 15 (45.5%) | |
| BRAF inhibitor ever | |||
| Yes | 1 (3.1%) | 13 (39.4%) | <0.001 |
| No | 31 (96.9%) | 20 (60.6%) | |
RT, radiation therapy; WBRT, whole brain radiation therapy; SRS, stereotactic radiosurgery; PS, performance status; RPA, recursive partitioning analysis; DS-GPA, diagnosis-specific graded prognostic assessment; LDH, lactate dehydrogenase.
1
One patient in the ipilimumab group had an ECOG PS of 3 and the remainder had PS of 2.
2
Not including ipilimumab. Prior therapies included interferon, interleukin-2, tumor-infiltrating lymphocytes, cytotoxic chemotherapy, and BRAF inhibitors (four patients in the ipilimumab group).
3
Not including ipilimumab. Subsequent therapies included cytotoxic chemotherapy and BRAF inhibitors (nine patients in the ipilimumab group).