Table 9. Concordance between IHC and endpoint RT-PCR based on molecular subtypes.
| IHC based | Endpoint RT-PCR based | κ value | OPA | |||
|---|---|---|---|---|---|---|
| Luminal-A | Luminal-B | HER2+ | TNBC | |||
| Luminal-A | 19 (61.3) | 4 (12.9) | 0 (0.0) | 8 (25.8) | 0.200* | 56.1 (23/41) |
| Luminal-B | 2 (28.6) | 3 (42.9) | 1 (14.3) | 1 (14.3) | ||
| HER2+ | 0 (0.0) | 1 (14.3) | 0 (0.0) | 0 (0.0) | ||
| TNBC | 1 (50.0) | 0 (0.0) | 0 (0.0) | 1 (50.0) | ||
| Total | 22 (53.7) | 8 (19.5) | 1 (2.4) | 10 (24.4) | ||
Values are presented as number (%) or % (number/number). IHC, immunohistochemistry; OPA, overall percent agreement; RT-PCR, reverse transcription PCR; TNBC, triple negative breast cancer; HER2, human epidermal growth factor receptor 2; +, positive. The sum of the percentages does not equal 100% because of rounding. *P < 0.05.