Kuter, I., Anderson, E., Emeribe, U., Finlay, Pauline, Nicholson, Robert Ian and Gee, Julia Margaret Wendy ORCID: https://orcid.org/0000-0001-6483-2015 2009. Comparison of methods for detection of fulvestrant-induced changes in breast tumor estrogen and progesterone receptor expression in a neoadjuvant trial (NEWEST) [Abstract]. Journal of Clinical Oncology 27 (15S) , e11602. |
Abstract
Background: Fulvestrant downregulates breast tumor estrogen and progesterone receptor (ER and PgR) levels in a dose-dependent manner. Using an Automated Cellular Imaging System (ACIS), NEWEST reported that 4-wks’ treatment with fulvestrant high-dose (HD, 500mg/month+500mg on Day 14 of Month 1) significantly reduced ER levels in primary breast tumors v approved-dose (AD, 250mg/month). However, no significant difference was detected between the two doses on PgR levels. To allow comparison with previous studies, a non-automated H-score assessment was performed and compared with ACIS. Methods: ER and PgR H-scores were derived by manual assessment of % tumor cells in each of 5 staining categories (negative, very weak, weak, moderate, strong) in the same sections scored by ACIS. This microscopic assessment was performed by 2 experienced observers blind to ACIS and clinical data. Mean % changes in H-scores were then calculated (table). Results: Both scoring methods showed a greater effect for fulvestrant HD v AD on ER expression at Wk 4, but H-score provided better dose discrimination. ACIS showed no difference between fulvestrant HD v AD on PgR expression at Wk 4, however, a significantly greater reduction in PgR expression was detected with fulvestrant HD using H-score. Conclusions: The choice of scoring method for determining ER and PgR expression in pharmacodynamic studies such as NEWEST is critical. Compared with H-scores, ACIS has a narrower dynamic range and reduced ability to discriminate fulvestrant HD v AD, particularly on PgR expression.
Item Type: | Article |
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Date Type: | Publication |
Status: | Published |
Schools: | Pharmacy |
Subjects: | R Medicine > RC Internal medicine > RC0254 Neoplasms. Tumors. Oncology (including Cancer) R Medicine > RM Therapeutics. Pharmacology |
Additional Information: | 2009 ASCO Annual Meeting Proceedings (Post-Meeting Edition) |
Publisher: | American Society of Clinical Oncology |
ISSN: | 0732-183X |
Last Modified: | 18 Oct 2022 14:21 |
URI: | https://orca.cardiff.ac.uk/id/eprint/17218 |
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