Table 3.
The presence of T-cells and immunohistochemical expression of IDO, TDO and PD-L1 classified by primary origin of the NET
| Jejunum/ileum N | Pancreas N | Lung N | Unknown N | Other Na | |
|---|---|---|---|---|---|
| Tissue samples | 22 | 14 | 2 | 8 | 5 |
| T-cells | |||||
| Absent | 13 | 11 | 0 | 5 | 1 |
| Present | 7 | 1 | 1 | 3 | 3 |
| Not evaluable | 2 | 2 | 1 | 0 | 1 |
| IDO expression | |||||
| Negative | 9 | 9 | 2 | 6 | 3 |
| Positive | 13 | 5 | 0 | 2 | 2 |
| TDO expression in tumour cells | |||||
| Negative | 15 | 6 | 2 | 3 | 3 |
| Positive | 4 | 6 | 0 | 5 | 2 |
| Not evaluable | 3 | 2 | 0 | 0 | 0 |
| TDO expression in stroma | |||||
| Negative | 2 | 12 | 1 | 5 | 3 |
| Positive | 15 | 1 | 0 | 1 | 1 |
| Not evaluable | 5 | 1 | 1 | 2 | 1 |
| PD-L1 expression | 0 | 0 | 0 | 0 | 0 |
| MMRp | 0 | 0 | 0 | 0 | 0 |
IDO indoleamine 2,3-dioxygenase, MMRp mismatch repair proteins, NET neuroendocrine tumour, PD-L1 programmed death-ligand 1, TDO tryptophan 2,3-dioxygenase
aOther sites of primary origin of the NET are stomach (N = 1), duodenum (N = 2), colon (N = 1), rectum (N = 1)