Table 2.
Oncogenic Mutation Testing Results in Different Specimens
| Testing Results | Pleural cfDNA (N = 54) | Pleural Cytology (N = 33) | Biopsy (N = 25) | Plasma cfDNA (N = 32) | P Value for Difference |
|---|---|---|---|---|---|
| Diagnostic yield,a No. (%) | 49 (90.7) | 16 (48.5) | 22 (88) | 24 (75) | < .001 |
| Positive | 43 (79.6) | 9 (27.2) | 20 (80) | 19 (59.3) | |
| True negative | 6 (11.1) | 7 (21.2) | 2 (8) | 5 (15.6) | |
| False negative | 2 (3.7) | 9 (27.3)b | 0 | 2 (6.2) | |
| Insufficient | 3 (5.5) | 8 (24.2) | 3 (12) | 6 (18.7) | |
| Not checked,c,d No. (%) | 0 | 21 (38.3) | 11 (20.3) | 0 | NA |
| No samples,c,e No. (%) | 0 | 0 | 18 (33.3) | 22 (40.7) | NA |
cfDNA = cell-free DNA.
a
Diagnostic yield: defined as ability to obtain a positive or true negative test for an oncogenic mutation in total No. of specimens tested: Positive + true negative specimens/total specimens tested (%).
b
Includes seven specimens with negative cytology for malignant cells but positive pleural cell-free DNA testing for mutations.
c
Denominator is 54 samples, which is the total pleural fluid samples collected.
d
Not checked. Samples available but mutation testing not done as per decision of the treating providers.
e
No samples. Samples were not obtained clinically.