Menopausal status does not predict Oncotype DX recurrence score

Adjuvant treatment for early stage, estrogen receptor (ER) positive invasive breast cancer has been based on prognosticators such as menopausal status. The recurrence score (RS) from the 21-gene assay Oncotype DX (ODX) is predictive of a 10-y distant recurrence in this population but is rarely applied to premenopausal patients. The relationship between menopausal status and RS was evaluated.

An institutional review board-approved retrospective review was conducted of invasive breast cancer patients with known RS. ODX eligibility was based on National Comprehensive Cancer Network guidelines or physician discretion. Perimenopausal women were classified as premenopausal for statistical analyses. Comparisons of menopausal status and RS were made using general linear regression model and the exact Wilcoxon rank-sum test.

Menopausal status was available for 575 patients (142 premenopausal, 433 postmenopausal). Median age was 46 y for premenopausal and 62 y for postmenopausal. Median invasive tumor size was 1.5 cm for both cohorts. Mastectomy rate was higher in the premenopausal group (54.8%) than postmenopausal (42%; P = 0.0001). Premenopausal women had a higher local-regional recurrence rate (2.8% versus 0%; P = 0.0384) but distant recurrence and overall survival were not statistically different (P = 0.6808). Median ER H-score was lower in premenopausal (H-score = 270) than postmenopausal women (H-score = 280; P < 0.0001). Median RS was 16 for both premenopausal (range, 0-54) and postmenopausal (range, 0-63) women. Menopausal status as a categorical variable was not predictive of RS (P-value = 0.6780).

Menopausal status has limited predictive power for distant recurrence. Therefore, menopausal status alone should not preclude performance of ODX in ER-positive, early stage breast cancer.