Cytokeratin 5/6 fingerprinting in HER2-positive tumors identifies a poor prognosis and trastuzumab-resistant basal-HER2 subtype of breast cancer.

There is an urgent need to refine the prognostic taxonomy of HER2+ breast carcinomas and develop easy-to-use, clinic-based prediction algorithms to distinguish between good- and poor- responders to trastuzumab-based therapy. Building on earlier studies suggesting that HER2+ tumors enriched with molecular and morpho-immunohistochemical features classically ascribed to basal-like tumors are highly aggressive and refractory to trastuzumab, we investigated the prognostic and predictive value of the basal-HER2+ phenotype in HER2-overexpressing tumors. Our retrospective cohort study of a consecutive series of 152 HER2+ primary invasive ductal breast carcinomas first confirmed the existence of a distinct subgroup co-expressing HER2 protein and basal cytokeratin markers CK5/6, the so-called basal-HER2+ phenotype.

An improved axillary staging system using the OSNA assay does not modify the therapeutic management of breast cancer patients.

The one-step nucleic acid amplification (OSNA) assay is a molecular procedure that can identify deposits of breast cancer (BC) cells in the sentinel lymph node (SLN). We examined the consistency of the OSNA assay with a classic hematoxylin-eosin (H&E)-based immunohistochemistry (IHC) study and evaluated how OSNA-based axillary staging might impact the therapeutic management of BC patients. SLN biopsy results were considered to be positive in 60 patients (40%) in the OSNA group (N = 148) and in 43 (28%) patients in the IHC cohort (N = 153, p = 0.

Synchronous solid neuroendocrine breast carcinoma and abdominal lymphoma: A case report and review of the literature.

Neuroendocrine tumors (NETs) are frequently associated with second primary malignancies (SPMs). Earlier studies have demonstrated that NETs are highly associated with synchronous or metachronous gastrointestinal and genitourinary SPMs. We report, for the first time, a case of pure NE breast carcinoma (NEBC) exhibiting all of the World Health Organization (WHO)-categorized morphological and phenotypic NE features (i.

Solid neuroendocrine breast carcinomas: incidence, clinico-pathological features and immunohistochemical profiling.

Primary pure neuroendocrine breast carcinomas (NEBC) have been considered special features within conventional breast carcinomas until recently. Indeed, the actual incidence of NEBC in BC populations has remained largely unknown due to the lack of unambiguous diagnostic criteria. In 2003, the World Health Organization (WHO) classification of breast tumors definitely established that the immunohistochemical expression of NE markers in more than 50% of the tumor cell population is the unique requisite for NEBC diagnosis.