Omitting Radiotherapy after Breast-Conserving Surgery in Luminal A Breast Cancer.

Background: Adjuvant radiotherapy is prescribed after breast-conserving surgery to reduce the risk of local recurrence. However, radiotherapy is inconvenient, costly, and associated with both short-term and long-term side effects. Clinicopathologic factors alone are of limited use in the identification of women at low risk for local recurrence in whom radiotherapy can be omitted.

Breast Cancer Molecular Subtype as a Predictor of Radiation Therapy Fractionation Sensitivity.

Purpose: The predictive benefit of breast cancer molecular subtypes for systemic therapy approaches has been well established; yet, there is a paucity of data regarding their use as a predictor of radiation therapy fractionation sensitivity. The purpose of this study was to determine whether rates of local recurrence (LR) for patients treated with hypofractionated (HF) radiation therapy, in comparison to conventional fractionation, differ across breast cancer molecular subtypes in a large, prospectively collected cohort treated with modern systemic therapy.

Methods And Materials: Patients who received a diagnosis of stage I-III breast cancer between 2005 and 2009 were identified.

Nestin expression in breast cancer: association with prognosis and subtype on 3641 cases with long-term follow-up.

Background: Basal-like breast cancers, originally recognized by gene expression profiling, can be clinically identified using immunohistochemical (IHC) definitions that require estrogen receptor (ER) negativity. However, some basal cases are ER positive and are mistakenly considered to be luminal by standard IHC approaches, leading to suboptimal treatment choices. Nestin, an intermediate filament expressed in many stem cells, is a recently identified positive marker of basal-like phenotype independent of ER status.

αB-crystallin Expression in Breast Cancer is Associated with Brain Metastasis.

Background/objectives: The molecular chaperone αB-crystallin is expressed in estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2 "triple-negative" breast carcinomas and promotes brain and lung metastasis. We examined αB-crystallin expression in primary breast carcinomas with metastatic data to evaluate its association with prognosis and site-specific metastases.

Methods: αB-crystallin gene () expression was examined using publically available global-gene expression data (n=855 breast tumors) with first site of distant metastasis information ("855Met").

Responsiveness of intrinsic subtypes to adjuvant anthracycline substitution in the NCIC.CTG MA.5 randomized trial.

Purpose: Recent studies suggest that intrinsic breast cancer subtypes may differ in their responsiveness to specific chemotherapy regimens. We examined this hypothesis on NCIC.CTG MA.