NOR-1 distinguishes acinic cell carcinoma from its mimics on fine-needle aspiration biopsy specimens.

Acinic cell carcinoma of the salivary gland (ACC-SG) is characterized by a recurrent chromosomal rearrangement (t(4; 9)(q13; q31)) that upregulates the transcription factor NR4A3. Studies conducted on formalin-fixed paraffin-embedded (FFPE) tissue have found that nuclear expression of a monoclonal antibody NR4A3 (NOR-1) is a sensitive and specific diagnostic marker for ACC-SG. The aims of this study were to evaluate the performance of the NOR-1 antibody and to compare its utility in separating ACC-SG from its mimics on cytology cell block specimens.

Effect of Hydrochloric Acid Decalcification on Expression Pattern of Prognostic Markers in Invasive Breast Carcinomas.

Context: In the United States, it is estimated that 100,000 people are living with metastatic breast cancer (BC) with bone representing the most common site of involvement. However, patients with isolated bone metastasis at presentation may have a longer survival. Therapeutic options for BC bone metastases often include systemic anticancer therapy (endocrine, chemotherapy, monoclonal antibodies, and/or other targeted therapies), which is largely dependent on the immunohistochemical (IHC) repertoire of the cancer for the prognostic markers [estrogen (ER) and progesterone receptors (PR), Ki-67, p53, and Her-2/neu] at its osseous metastatic site.

Comparison of PAX6 and PAX8 as immunohistochemical markers for pancreatic neuroendocrine tumors.

To compare the utility of PAX6 and PAX8 as immunohistochemical markers for neuroendocrine tumors (NETs) of pancreatic origin, we performed PAX6 and PAX8 immunostains on 178 NETs, including 110 primary NETs (26 pancreatic, 10 gastric, 12 duodenal, 22 jejuno-ileal, 10 rectal, 30 pulmonary) and 68 NETs metastatic to the liver (24 pancreatic, 1 duodenal, 37 jejuno-ileal, 1 rectal, 5 pulmonary). Among primary NETs, PAX6 and PAX8 were positive in 65 % (17/26) and 73 % (19/26) of pancreatic, 0 % (0/10) and 10 % (1/10) of gastric, 92 % (11/12) and 92 % (11/12) of duodenal, 0 % (0/22) and 0 % (0/22) of jejuno-ileal, 90 % (9/10) and 80 % (8/10) of rectal, and 0 % (0/30) and 23 % (7/30) of pulmonary NETs, respectively. PAX6 and PAX8 positivity was seen in 46 % (11/24) and 50 % (12/24) of metastatic pancreatic NETs to the liver, respectively.

Evaluation of a triple combination of cytokeratin 20, p53 and CD44 for improving detection of urothelial carcinoma in urine cytology specimens.

Background: Atypical urine cytology results trigger cystoscopy or molecular tests, both of which are costly, complex and difficult to perform tests. Several immunostains are being investigated to improve cancer detection; however, cytology material is limited and restricts the use of multiple immunostains. This study was designed to determine the utility of a cocktail of three stains, cytokeratin (CK20), p53 and CD44 in urine cytology samples for improving the detection of urothelial carcinoma.

Uroplakin II outperforms uroplakin III in diagnostically challenging settings.

Aims: We performed a head-to-head comparison of an antibody against uroplakin III (UP3) and a new uroplakin II (UP2) antibody that remains untested in diagnostically challenging settings.

Methods And Results: We immunostained high-grade bladder neck carcinomas (n = 35), high-grade upper tract urothelial carcinomas (UC) and renal carcinomas (n = 85), metastases of UC (n = 30) and a multicancer tissue microarray (n = 88) for UP3 and UP2, and scored staining intensity and proportion. UP3 showed membranous plaque-like expression, while UP2 staining showed both membranous and cytoplasmic positivity.

Clinicopathological significance of HER2/neu genetic heterogeneity in HER2/neu non-amplified invasive breast carcinomas and its concurrent axillary metastasis.

Background: HER2/neu (HER2) is a significant prognostic marker for breast carcinomas. Recently, new guidelines defining HER2 genetic heterogeneity (GH) were published by the College of American Pathologists.

Aims: To determine the prevalence of HER2 GH as defined in primary invasive breast carcinoma, to determine its relationship with prognostic variables and to investigate its impact on concurrent axillary metastasis.

Ki-67 proliferative index predicts progression-free survival of patients with well-differentiated ileal neuroendocrine tumors.

Ki-67 proliferative index (Ki-67 index) is suggested to be an important prognostic variable and is included as one of the grading parameters for neuroendocrine tumors. The present study was undertaken to determine the usefulness of the Ki-67 index and the corresponding tumor grade in predicting progression-free survival (PFS) of patients with ileal well-differentiated neuroendocrine tumors (wNETs). Tumors from 57 patients with ileal wNETs were studied.

Lack of HER2 overexpression and amplification in small intestinal adenocarcinoma.

HER2 overexpression and amplification have been studied as a therapeutic and prognostic target in a number of human cancers, including esophageal, gastric, and colorectal adenocarcinomas. However, HER2 status has not been well investigated in primary small intestinal adenocarcinoma, probably because of its rarity. In this study, we conducted immunohistochemical analysis and fluorescence in situ hybridization (FISH) for HER2 on 49 primary nonampullar small intestinal adenocarcinomas.

Expression of hepatocyte antigen in small intestinal epithelium and adenocarcinoma.

Hepatocyte antigen is recognized by antibody Hep Par 1, a widely used diagnostic immunomarker for hepatocellular carcinoma and tumors with hepatoid differentiation. Hepatocyte antigen expression has also been detected in nonneoplastic small intestinal epithelium, but expression in small intestinal adenocarcinoma has not been well investigated. We immunohistochemically examined 39 nonampullary small intestinal adenocarcinomas for hepatocyte antigen expression; 34 cases contained normal-appearing nonneoplastic small intestinal mucosa on the same tissue sections.

Evaluation of EGFR abnormalities in patients with pulmonary adenocarcinoma: the need to test neoplasms with more than one method.

Patients with advanced pulmonary adenocarcinoma exhibiting overexpression or mutation of epidermal growth factor receptor tend to respond better to targeted therapy with tyrosine kinase inhibitors such as gefitinib and erlotinib. There is no consensus regarding how these neoplasms should be routinely tested for epidermal growth factor receptor (EGFR) and whether the results of immunohistochemistry (IHC), mutation analysis and fluorescent in situ hybridization correlate with each other or are independent predictive variables. We tested 100 pulmonary adenocarcinomas from patients with stage III or IV disease for EGFR abnormalities using IHC, PCR and fluorescent in situ hybridization (FISH) and compared the results using kappa and other statistical methods.

BD ProEx C: a sensitive and specific marker of HPV-associated squamous lesions of the cervix.

BD ProEx C (ProEx C) is a recently developed immunocytochemical assay that targets the expression of topoisomerase II-alpha and minichromosome maintenance protein-2, 2 genes shown to be overexpressed in cervical cancers. Recent studies validated this reagent in liquid-based cytology specimens and suggested its usefulness as an adjunct in the diagnosis of challenging cases. Limited information is available on its expression in tissue sections.