Table 1.
| Total | CTC-detectable | CTC-undetectable | p-value | |
|---|---|---|---|---|
| n=48 | n=20 | n=28 | ||
| Age at enrollment (median, range) | 69.5 years (55–89 years) | 70.5 years (59–89 years) | 67.5 years (55–84 years) | 0.63 |
| Sex (female) | 26 (54%) | 14 (70%) | 12 (43%) | 0.08 |
| Race | 0.86 | |||
| Caucasian | 37 (77%) | 16 (80%) | 21 (75%) | |
| African American | 9 (19%) | 3 (15%) | 6 (21%) | |
| Other | 2 (4%) | 1 (5%) | 1 (4%) | |
| Smoking status | 0.49 | |||
| Current | 12 (25%) | 4 (20%) | 8 (29%) | |
| Former | 34 (71%) | 16 (80%) | 18 (64%) | |
| Never | 2 (4%) | 0 (0%) | 2 (7%) | |
| Pack-years (median, range) | 40 (3.5–165) | 37.5 pack-years (4.5–75 pack-years) | 45 pack-years (3.5–165 pack-years) | |
| Tumor size (median, range) | 1.4 cm (0.5–3.8) | 1.2 cm (0.5–3.2 cm) | 1.75 cm (0.9–3.8 cm) | 0.08 |
| Tumor SUV (median, range) | 3 (0.8–19.9) | 2.6 (0.8–12.7) | 3.1 (0.8–19.9) | 0.40 |
| T stage | 0.31 | |||
| 1a | 35 (73%) | 17 (85%) | 18(64%) | |
| 1b | 10 (21%) | 2 (10%) | 8 (29%) | |
| 2a | 3 (6%) | 1 (5%) | 2 (7%) | |
| Prior history NSCLC | 0.01 | |||
| Yes | 10 (21%) | 8 (40%) | 2 (7%) | |
| No | 38 (79%) | 12 (60%) | 26 (93%) |
Detection and monitoring of CTCs may be useful in patients with early stage NSCLC when definitive tissue diagnosis cannot be confirmed by biopsy. We present a pilot prospective assessment of 48 clinical stage I NSCLC patients treated with SBRT undergoing serial CTC monitoring with a novel, telomerase-based assay. Our results suggest that CTC monitoring in this patient population is feasible and potentially useful in enhancing clinical diagnosis and detection of recurrent or progressive disease.