Table 1. ER/PR levels by IHC staining from patients treated with CDK4/6 inhibitors.
| Patient number | Drug | Duration (months) |
Pretreatment |
Post-treatment |
||
|---|---|---|---|---|---|---|
| ER | PR | ER | PR | |||
| 1 | LEE011 | 13 | 99 | 90 | 85 | <1 |
| 2 | LEE011 | 4 | 25 | 0 | 0 | 0 |
| 3 | LY2835219 | 11 | 90 | 0 | 0 | 0 |
| 4 | LEE011 | 9 | 98 | 0 | 2 | 0 |
| 5 | LEE011 | 5 | 99 | 0 | 95 | 0 |
| 6 | LEE011 | 8 | ‘++' external | ‘0' | 60 | 0 |
| 7 | LY2835219 | 6 | + | − | 70 | 30 |
Abbreviations: CLIA, ChemiLuminescent Immuno Assay; ER, estrogen receptor; IHC, immunohistochemistry; PR, progesterone receptor.
Immunohistochemical analysis of ER and PR in tumor biopsies from patients treated either with LEE011 or LY2835219 for metastatic breast cancer. Reported is the % staining using standard CLIA assays for ER and PR levels.