Relationship between quantitative estrogen and progesterone receptor expression and human epidermal growth factor receptor 2 (HER-2) status with recurrence in …
M Dowsett, C Allred, J Knox, E Quinn… - Journal of clinical …, 2008 - ascopubs.org
Journal of clinical oncology, 2008•ascopubs.org
Purpose To determine the relationship between quantitative estrogen-receptor (ER) and
progesterone-receptor (PgR) expression and human epidermal growth factor 2 (HER-2)
status with time to recurrence (TTR) in postmenopausal women with hormone receptor–
positive primary breast cancer treated with anastrozole or tamoxifen as adjuvant therapy.
Patients and Methods Formalin-fixed, paraffin-embedded tumor blocks were retrospectively
collected from patients in the monotherapy arms of the Arimidex, Tamoxifen Alone or in …
progesterone-receptor (PgR) expression and human epidermal growth factor 2 (HER-2)
status with time to recurrence (TTR) in postmenopausal women with hormone receptor–
positive primary breast cancer treated with anastrozole or tamoxifen as adjuvant therapy.
Patients and Methods Formalin-fixed, paraffin-embedded tumor blocks were retrospectively
collected from patients in the monotherapy arms of the Arimidex, Tamoxifen Alone or in …
Purpose
To determine the relationship between quantitative estrogen-receptor (ER) and progesterone-receptor (PgR) expression and human epidermal growth factor 2 (HER-2) status with time to recurrence (TTR) in postmenopausal women with hormone receptor–positive primary breast cancer treated with anastrozole or tamoxifen as adjuvant therapy.
Patients and Methods
Formalin-fixed, paraffin-embedded tumor blocks were retrospectively collected from patients in the monotherapy arms of the Arimidex, Tamoxifen Alone or in Combination (ATAC) trial and centrally tested for ER, PgR and HER-2. ER and PgR were scored using continuous scales and HER-2 was scored as 0 to 3+ with 2+ cases being analyzed by fluorescence in situ hybridization.
Results
Blocks were collected from 2,006 of 5,880 eligible patients. Tissue was assessable and ER and/or PgR positivity confirmed centrally in 1,782 cases. In these, TTR was longer for anastrozole than for tamoxifen by a similar extent to that in the overall trial. None of the three biomarkers identified a set of patients with differential benefit from anastrozole over tamoxifen. Patients with low ER, low PgR, and high HER-2 expression had a poorer prognosis with either drug. Only 2.6% of patients in the highest quartile of PgR experienced recurrence after 5 years, compared with 13.2% in the lowest quartile.
Conclusion
Quantitative expression of ER and PgR and HER-2 status did not identify patients with differential relative benefit from anastrozole over tamoxifen: TTR was longer for anastrozole than for tamoxifen in all molecular subgroups. Low ER or PgR or high HER-2 expression are associated with a high risk of recurrence with either anastrozole or tamoxifen.
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