Racial disparity in estrogen receptor positive breast cancer patients receiving trimodality therapy

• Published in: Breast (Edinburgh) Vol. 21; no. 3; pp. 276 - 283
• Main Authors: Wright, J.L, Reis, I.M, Zhao, W, Panoff, J.E, Takita, C, Sujoy, V, Gomez, C.R, Jorda, M, Franceschi, D, Hurley, J
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.06.2012
• Subjects: Adult; African Americans - statistics & numerical data; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Breast cancer; Breast Neoplasms - ethnology; Breast Neoplasms - metabolism; Breast Neoplasms - therapy; Chemotherapy, Adjuvant; Cohort Studies; Combined Modality Therapy; Estrogen receptor; European Continental Ancestry Group - statistics & numerical data; Female; Follow-Up Studies; Hematology, Oncology and Palliative Medicine; Humans; Middle Aged; Neoplasm Staging; Neoplasms, Hormone-Dependent - etiology; Neoplasms, Hormone-Dependent - metabolism; Neoplasms, Hormone-Dependent - therapy; Prognosis; Racial disparity; Radiotherapy, Adjuvant; Receptor, ErbB-2 - metabolism; Receptors, Estrogen - metabolism; Receptors, Progesterone - metabolism; Trimodality therapy; Triple negative; United States - epidemiology; Young Adult; United States; Trimodality therapy; Estrogen receptor; Breast cancer; Triple negative; Racial disparity
• ISSN: 0960-9776; 1532-3080
• DOI: 10.1016/j.breast.2011.11.003

Abstract Introduction We assessed racial differences in progression-free survival (PFS) and overall survival (OS) in relation to subtype in uniformly treated stage II–III breast cancer patients. Methods We reviewed records of 582 patients receiving post-mastectomy radiation (PMRT) between 1/1999 and 12/2009 and evaluated the effect of demographic, tumor, and treatment characteristics on PFS and OS. Results Median follow up was 44.7 months. 24% of patients were black and 76% white. All had mastectomy and PMRT; 98% had chemotherapy; Estrogen receptor (ER)+ patients received endocrine therapy. Black patients were more likely to have ER− (56% vs. 38%, p  = 0.0001), progesterone receptor (PR)− (69% vs. 54%, p  = 0.002), and triple negative (TN) (46% vs. 24%, p  < 0.0001) tumors. Overall, black patients had worse PFS (60.6% vs. 78.3%, p  = 0.001) and OS (72.8% vs. 87.7%, p  < 0.0001). There was no racial difference in PFS ( p  = 0.229 and 0.273 respectively) or OS ( p  = 0.113 and 0.097 respectively) among ER− or TN. Among ER+, black patients had worse PFS (55% vs. 81%, p  < 0.001) and OS (73% vs. 91%, p  < 0.0001). The difference in PFS was seen in the ER+/PR+/HER2− subgroup ( p  = 0.002) but not ER+/PR−/HER2− ( p  = 0.129), and in the post-menopausal ER+/HER2− subgroup ( p  = 0.004) but not pre/peri-menopausal ER+/HER2− ( p  = 0.150). Conclusions Black women had worse survival outcomes in this cohort. This disparity was driven by (1) a higher proportion of ER− and TN tumors in black women and (2) worse outcome of similarly treated black women with ER+ breast cancer. The underlying causes of racial disparity within hormone receptor categories must be further examined.