Table 1.
Study patients’ characteristics
| All patients | ΔNACT | ΔNACT | p-value | ||
|---|---|---|---|---|---|
| <224 pg/ml | >224 pg/ml | ||||
| (n = 66) | (n = 48) | (n = 18) | |||
| n (%) | n (%) | n (%) | |||
| Median age (range), years | 59 (30–73) | 57 (30–72) | 61 (50–73) | 0.0281 | |
| Gender | Male | 38 (58) | 28 (58) | 10 (56) | 0.842 |
| Female | 28 (42) | 20 (42) | 8 (44) | ||
| TN stage | T2–3 | 45 (68) | 31 (65) | 14 (78) | 0.312 |
| T4 | 21 (32) | 17 (35) | 4 (22) | ||
| N0–1 | 16 (24) | 10 (21) | 6 (33) | 0.353 | |
| N2 | 49 (75) | 37 (77) | 12 (67) | ||
| ND | 1 | 1 | 0 | ||
| Baseline CEA level | ≤ULN | 38 (58) | 25 (52) | 13 (72) | 0.142 |
| >ULN | 28 (42) | 23 (48) | 5 (28) | ||
| Baseline haemoglobin level | ≥LLN | 54 (82) | 39 (81) | 15 (83) | 13 |
| <LLN | 12 (18) | 9 (19) | 3 (17) | ||
| ypTN stage | ypT0–2 | 37 (56) | 22 (46) | 15 (83) | 0.0082 |
| ypT3–4 | 28 (42) | 25 (52) | 3 (17) | ||
| ND | 1 | 1 | 0 | ||
| ypN0 | 46 (70) | 29 (60) | 17 (94) | 0.0092 | |
| ypN | ypN1–2 | 19 (29) | 18 (38) | 1 (6) | |
| ND | 1 | 1 | 0 | ||
| TRG score | TRG1–2 | 44 (67) | 30 (63) | 14 (78) | 0.282 |
| TRG3–5 | 21 (32) | 17 (35) | 4 (22) | ||
| ND | 1 | 1 | 0 | ||
The population of 66 study patients with paired serum sample measurements of carbonic anhydrase IX following neoadjuvant induction chemotherapy versus baseline (a variable termed ΔNACT) was divided into two groups above and below an estimated optimum cut-off ΔNACT value of 224 pg/ml. Distribution of parameters between the two groups was compared using 1: Mann-Whitney U-test, 2: Pearson’s chi-square test or 3: Fisher’s exact test
ND not determined (omitted from analysis), CEA carcinoembryonic antigen, ULN upper limit of normal, LLN lower limit of normal, TRG tumour regression grade