Deconstructing Breast Cancer Heterogeneity: Clinical Implications for Women With Basal-Like Tumors

Nabila S. Rattani

Theresa Swift-Scanlan

basal-like, breast cancer, risk factors, epigenetic, treatment, BRCA1
ONF 2014, 41(6), 639-646. DOI: 10.1188/14.ONF.639-646

Purpose/Objectives: To compare and contrast the molecular and environmental factors contributing to basal-like breast cancer and highlight the clinical implications for women with this phenotype.

Data Sources: CINAHL® and PubMed databases, journals, and citation indices were searched using the key word basal-like in combination with breast cancer, epigenetic, treatment, subtype, risk factor, and BRCA1 to synthesize the literature on the multiple underpinnings of basal-like breast cancer.

Data Synthesis: Research findings related to the molecular foundation of basal-like breast cancer were integrated with knowledge of nongenetic contributing risk factors. Approved therapies and those under development were summarized with the goal of improving understanding for research and practice.

Conclusions: Of the five subtypes of breast cancer, the basal-like subtype has the shortest survival and poorest prognosis. The development of gene expression assays with epigenetic studies has enabled reliable identification of the basal-like subtype and has shed light on novel therapeutic possibilities. Clinical trials for basal-like breast cancer are underway, and the potential for individualized treatments for women with this subtype show promise.

Implications for Nursing: The main difficulties with basal-like breast cancer are its aggressive course, treatment refractory nature, and complex biology, all of which pose real challenges for clinical management and patient education. Oncology nurses play a pivotal role in providing holistic care and patient support. Therefore, nurses must understand the complexity of the clinical presentation and the underlying biology of this cancer subtype.

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