Table 4.
Difference in proportion and intensity of Ki-67 (Leica, MM1 mouse monoclonal) nuclear stain; formalin fixation and paraffin embedding control decile value in parenthesis
| Validation case number (diagnosis) | CBF decile difference from FFPE | CBF intensity difference from FFPE | CBA decile difference compared with FFPE | CBA intensity difference from FFPE |
|---|---|---|---|---|
| V1 (neuroendocrine) | −1 (20-30) | 1 | −2 (20-30) | <1 |
| V2 (adenocarcinoma) | −1 (0-10) | N/A | −1 (0-10) | N/A |
| V3 (metastatic carcinoma) | 0 (10-20) | 1 | −1 (10-20) | <1 |
| V5 (adenocarcinoma) | −2 (20-30) | <1 | −1 (20-30) | 1 |
| V6 (squamous cell carcinoma) | −1 (10-20) | <1 | 0 (10-20) | 1 |
| V7 (adenocarcinoma) | 0 (40-50) | 1 | −2 (40-50) | 1 |
| V11 (adenocarcinoma) | 0 (0-10) | 1 | −1 (0-10) | 1 |
| V12 (adenocarcinoma) | <1 (0-10) | <1 | <1 (0-10) | <1 |
FFPE: Formalin-fixed paraffin-embedded histology tissue which serves as the control, Ki- 67 was scored as tenths with <0%, 1%-10%, 11%-20%, etc. The proportion of cells stained is either equal to (hence difference is 0) or less than those stained in the FFPE tissue. The latter is denoted by the (−) in front of the decile difference such that -2 amounts to 2 decile decreased staining compared with FFPE tissue. The intensity was graded as 1 if it was equal to or greater than the control FFPE tissue, <1% if it was less intense than control FFPE staining and 0 if there was no staining. CBA: Cell Blocks fixed in alcohol