Use of immunohistochemical markers can refine prognosis in triple negative breast cancer

Abstract

Background: Basal-like breast cancer has been extensively characterized on the basis of gene expression profiles, but it is becoming increasingly common for these tumors to be defined on the basis of immunohistochemical (IHC) staining patterns, particularly in retrospective studies where material for expression profiling may not be available. The IHC pattern that best defines basal-like tumors is under investigation and various combinations of ER, PR, HER2-, CK5/6+ and EGFR+ have been tested.

Basal-like and triple-negative breast cancers: a critical review with an emphasis on the implications for pathologists and oncologists

“…The main characteristics of triple-negative cancers that have emerged from the literature illustrate their similarities to basal-like cancers, including the fact that they more frequently affect younger patients (o50 years), 24,30,31,59,61,62 are more prevalent in African-American women, [62][63][64] often present as interval cancers, and are significantly more aggressive than tumors of other molecular subtypes. 24,28,59,[61][62][63] This aggressiveness is best exemplified by the fact that the peak risk of recurrence is between the first and third years and the majority of deaths occur in the first 5 years following therapy.…”

“…24,28,59,[61][62][63] This aggressiveness is best exemplified by the fact that the peak risk of recurrence is between the first and third years and the majority of deaths occur in the first 5 years following therapy. 59,61 Patients with triple-negative cancers, 59,63 similar to those with basal-like cancers, 42 have a significantly shorter survival following the first metastatic event when compared with those with non-basal-like/non-triple-negative controls.…”

Triple-negative breast cancers express receptors for growth hormone-releasing hormone (GHRH) and respond to GHRH antagonists with growth inhibition

“…Although triple-negative cancers are sensitive to chemotherapy [1], the prognosis of patients with such tumors is poor. Thus, in patients with triple-negative cancers disease recurrence takes place earlier and most of deaths occur in the first 5 years after diagnosis [2,7]. These clinical findings underline the paramount importance of the development of the novel targeted therapies for triplenegative breast cancers.…”

The proteins FABP7 and OATP2 are associated with the basal phenotype and patient outcome in human breast cancer

“…In spite of this, recent studies have raised the issue that some basal CK expressing (CK5/6, 14, 17) tumours are positive for ER and HER2, questioning general validity of the triple-negative method [23] and its reliance on negative results without inclusion of positive entry criteria. Several studies have attempted to refine the classification of the group by using a broader range of markers including the basal cytokeratins 5/6 and 14 and other basal associated markers such as epidermal growth factor receptor (EGFR), vimentin and P-cadherin [14,24].…”