Table 3.
Sensitivity and specificity of pan-Trk immunohistochemistry for detecting NTRK fusions
| Sensitivity | ||
|---|---|---|
| NTRK1 | 96.2% (26/27) | |
| NTRK2 | 100% (5/5) | |
| NTRK3 | 79.4% (27/34) | |
| Sensitivity | Specificity | |
| Total | 87.9% (58/66) | 81.1% (257/317) |
| Colon | 87.5% (7/8) | 100% (25/25) |
| Lung | 87.5% (7/8) | 100% (24/24) |
| Thyroid | 81.8% (9/11) | 100% (27/27) |
| Salivary | 88.9% (8/9) | 52% (13/25) |
| Breast | 80% (4/5) | 82.1% (23/28) |
| Inflammatory myofibroblastic tumor | 100% (3/3) | 100% (5/5) |
| Sarcoma | 80% (8/10) | 74.4% (29/39) |
| Pancreas | (0/0)a | 100% (20/20) |
| Appendix | 100% (1/1) | 100% (1/1) |
| Cholangio | 100% (2/2) | 100% (19/19) |
| Glioma | 100% (6/6) | 20.8% (5/24) |
| Melanoma | 100% (3/3) | 100% (17/17) |
| Neuroendocrine | (0/0)a | 88.9% (8/9) |
| Small round cell tumorb | (0/0) | 45.8% (11/24) |
| Otherc | (0/0) | 100% (30/30) |
The NTRK fusion positive pancreatic adenocarcinoma and pancreatic neuroendocrine tumor cases were detected on cytology specimens, and no material remained available for immunohistochemical studies
Small round cell tumors included embryonal rhabdomyosarcoma (8), neuroblastoma (5), Ewing sarcoma (5), desmoplastic small round cell tumor (5), and NUT midline carcinoma (1)
Other tumor types included prostatic adenocarcinoma (9), high-grade serous ovarian carcinoma (7), endometrioid adenocarcinoma (4), ampullary carcinoma (2), esophageal adenocarcinoma (2), esophageal squamous cell carcinoma (1), uterine perivascular epithelioid cell tumor (1), histiocytosis (1), myoepithelial carcinoma (1), granular cell tumor (1), and cancer of unknown primary (1)