Table 1.
Patient characteristics
| All patients | ctDNA detected | ctDNA not detected | ||||
|---|---|---|---|---|---|---|
| Total | 63 | 19 | 44 | |||
| Age (median) | 70 | (52–83) | 68 | (52–83) | 70 | (52–81) |
| Sex | ||||||
| Female | 38 | 60% | 11 | 58% | 27 | 61% |
| Male | 25 | 40% | 8 | 42% | 17 | 39% |
| Smoking status | ||||||
| Smoker/former smoker | 59 | 94% | 17 | 89% | 42 | 95% |
| Never smoker | 4 | 6% | 2 | 11% | 2 | 5% |
| Histology | ||||||
| Adenocarcinoma | 57 | 90% | 16 | 84% | 41 | 93% |
| Non-adenocarcinoma | 6 | 10% | 3 | 16% | 3 | 7% |
| WHO performance status | ||||||
| 0 | 37 | 59% | 11 | 58% | 26 | 59% |
| 1 | 23 | 37% | 8 | 42% | 15 | 34% |
| 2 | 2 | 3% | 0 | 0% | 2 | 5% |
| 3 | 1 | 2% | 0 | 0% | 1 | 2% |
| Disease stage | ||||||
| I | 28 | 44% | 0 | 0% | 28 | 64% |
| II | 12 | 19% | 5 | 26% | 7 | 16% |
| III | 23 | 37% | 14 | 74% | 9 | 20% |
| Treatment | ||||||
| Surgery | 48 | 76% | 8 | 42% | 40 | 91% |
| Curative radiotherapy with or without chemotherapy | 11 | 17% | 9 | 47% | 2 | 5% |
| Palliative therapy | 4 | 6% | 2 | 11% | 2 | 5% |
| ctDNA detection method | ||||||
| NGS* | 33 | 52% | 13 | 68% | 20 | 45% |
| ddPCR | 30 | 48% | 6 | 32% | 24 | 55% |
| 18 F-FDG PET/CT parameters (median) | ||||||
| MTV (cm3) | 7.5 | 61.2 | 3.7 | |||
| TLG (g/mL x cm3) | 39.1 | 460.5 | 14.8 | |||
| SUVmax (g/mL) | 11.8 | 19.2 | 9.1 | |||
*One patient was included from a study analyzing ctDNA by a 275 NGS gene panel, and cfDNA from the other 32 patients was analyzed by patient-specific NGS panels. ddPCR: droplet digital polymerase chain reaction, NGS: next-generation sequencing, MTV: metabolic tumor volume, SUV: standardized uptake value, TLG: total lesion glycolysis