Sex Disparity Observed for Oncotype DX Breast Recurrence Score in Predicting Mortality Among Patients with Early Stage ER-Positive Breast Cancer.

Wang F1,2, Reid S3, Zheng W1, Pal T4, Meszoely I5, Mayer IA3, Bailey CE5, Park BH3, Shu XO6.

Author information

1: Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, Tennessee.
2: Department of Breast Surgery, the Second Hospital of Shandong University, Jinan, Shandong, P. R. China.
3: Division of Hematology/Oncology, Department of Medicine, Breast Cancer Program, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, Tennessee.
4: Division of Genetic Medicine, Department of Medicine, Vanderbilt Genetics Institute, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, Tennessee.
5: Division of Surgical Oncology and Endocrine Surgery, Department of Surgery, Vanderbilt University Medical Center, Nashville, Tennessee.
6: Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, Tennessee. xiao-ou.shu@vumc.org.

Abstract

PURPOSE:

Prognostic value of Oncotype DX Breast Recurrence Score (RS) in male patients with breast cancer is understudied. We evaluated associations of RS with overall mortality in male patients with breast cancer and compared it with female counterparts.

EXPERIMENTAL DESIGN:

With a cohort of 848 male and 110,898 female patients with breast cancer identified from the National Cancer Database (2010-2014), we estimated HRs and 95% confidence intervals (CI) for overall mortality associated with RS using Cox regression models. RS was evaluated continuously, as well as by categorization following respective traditional (≤17, 18-30, and ≥31) and TAILORx (≤10, 11-25, and ≥26) cutoffs.

RESULTS:

RS was positively associated with mortality in male patients (HR = 1.13; 95% CI, 1.02-1.26 per unit RS increment) up to RS > 21, after which the risk plateaued. Among female patients, mortality began to increase with RS only when RS > 23 (HR = 1.02; 95% CI, 1.01-1.02 per unit of RS increment). The intermediate- (HR = 5.37; 95% CI, 1.79-16.11) and high-risk diseases (HR = 4.28; 95% CI, 1.22-14.97) defined by TAILORx, but not traditional cutoffs established for female patients, were associated with elevated mortality risk in men even after adjustment for demographic, clinical characteristics, and treatments, except chemotherapy.

CONCLUSIONS:

RS is associated with mortality in male patients with breast cancer at a much lower threshold than that for female patients. Studies are needed to establish specific guidelines for RS thresholds for male patients with breast cancer.