Table 1.
Characteristics of advanced NSCLC patients treated with checkpoint inhibitors
| Total population (n = 104) | Patients with CTC at T0 (n = 33) | Patients without CTC at T0 (n = 71) | |
|---|---|---|---|
| n (%) | n (%) | n (%) | |
| Age | |||
| Median (range) | 65 (29–83) | 67 (41–83) | 65 (29–80) |
| Gender | |||
| Male | 58 (44) | 17 (51) | 41 (58) |
| Female | 46 (56) | 16 (49) | 30 (42) |
| ECOG PS* | |||
| 0 | 50 (48) | 9 (27) | 41 (58) |
| 1 | 52 (50) | 23 (70) | 29 (41) |
| 2 | 2 (2) | 1 (3) | 1 (1) |
| Smoking status | |||
| Smokers | 94 (90) | 28 (85) | 66 (93) |
| Non smokers | 3 (3) | 2 (6) | 1 (1) |
| Unknown | 7 (7) | 3 (9) | 4 (6) |
| Stage | |||
| III | 12 (11) | 1 (3) | 1 (16) |
| IV | 92 (89) | 32 (97) | 60 (84) |
| Histology | |||
| Adenocarcinoma | 76 (73) | 24 (72) | 52 (73) |
| Squamous cell carcinoma | 27 (26) | 8 (24) | 19 (27) |
| Carcinosarcoma | 1 (1) | 1 (4) | 0 (0) |
| Therapy line | |||
| 1 | 4 (4) | 3 (4) | 1 (3) |
| 2 | 87 (84) | 59 (83) | 28 (85) |
| ≥3 | 13 (12) | 9 (13) | 4 (12) |
| Metastatic sites | |||
| 0 | 15 (14) | 2 (6) | 13 (18) |
| 1 | 37 (36) | 13 (41) | 24 (34) |
| 2 | 35 (34) | 12 (38) | 23 (32) |
| 3 | 10 (10) | 4 (13) | 6 (9) |
| > 3 | 6 (6) | 1 (3) | 5 (7) |
| Mutations a | |||
| None identified | 46 (44) | 18 (55) | 39 (55) |
| KRAS | 33 (32) | 9 (27) | 24 (34) |
| Other | 14 (13) | 6 (18) | 8 (11) |
| PD-L1 b | |||
| < 1% | 44 (43) | 16 (49) | 28 (39) |
| 1–49% expression | 19 (18) | 7 (21) | 12 (17) |
| ≥50% expression | 18 (17) | 5 (15) | 13 (18) |
| Not evaluable c | 23 (22) | 5 (15) | 18 (25) |
| Therapy | |||
| Nivolumab | 89 (85) | 29 (85) | 60 (83) |
| Pembrolizumab | 8 (8) | 2 (6) | 6 (9) |
| Atezolizumab | 5 (5) | 1 (3) | 4 (7) |
| Ipilimumab/Nivolumab | 2 (2) | 1 (3) | 1 (1) |
| Response d | |||
| Complete Response | 4 (4) | 0 (0) | 4 (6) |
| Partial Response | 26 (25) | 7 (21) | 19 (27) |
| Stable Disease | 24 (23) | 5 (15) | 19 (27) |
| Progressive Disease | 50 (48) | 21 (61) | 29 (39) |
| Durable response e | |||
| > 6 months | 64 (62) | 7 (21) | 33 (46) |
| < 6 months | 40 (38) | 26 (79) | 38 (54) |
*Eastern Cooperative Oncology Group Performance Score, patients with CTC had significantly more often PS ≥1 than patients without CTC (p = 0.02)
aMutations were identified by NGS, specifically the Ion Torrent using an in-house panel (IonPGM-v002) (adenocarcinoma). DNA amplifications and rearrangements were detected by means of FISH (adenocarcinoma and squamous cell carcinoma)
bPD-L1 expression was measured by certified pathologists on at least 100 tumor cells with 22C3 antibodies
cPD-L1 could not be evaluated in 23 patients as biopsied material was of insufficient quality or quantity
dRevised Response Evaluation Criteria In Solid Tumor v1.1, Non evaluable was due to early death of the patient
eDurable response was defined as SD, PR or CR for at least 6 months. Those who had a shorter tumor response duration had more often CTC (p = 0.01)