Relationship between paired pre-CRT/post-CRT ctDNA status and pCR in 144 patients where both results are available
| pCR | Non-pCR | |
| Pretreatment ctDNA positive, n/total n (%) | ||
| Post-CRT ctDNA positive | 1/21 (5) | 11/91 (12) |
| Post-CRT ctDNA negative | 20/21 (95) | 80/91 (88) |
| Pretreatment ctDNA negative, n/total n (%) | ||
| Post-CRT ctDNA positive | 0/8 (0) | 0/24 (0) |
| Post-CRT ctDNA negative | 8/8 (100) | 24/24 (100) |
CRT, chemoradiation; ctDNA, circulating tumour DNA; pCR, pathological complete response.