Palladin is a marker of liver metastasis in primary pancreatic endocrine carcinomas.

BACKGROUND: Palladin is a metastasis-associated gene regulating cell motility. The expression of palladin protein in pancreatic neuroendocrine tumors (PET) and carcinomas (PECA) is not known. MATERIALS AND METHODS: A tissue microarray (TMA) of well-differentiated (WD) PETs/PECAs (AJCC 2010) and non-neoplastic, histologically normal pancreatic tissue/islets (HNPIs) was immunostained with palladin antibody and quantified using the Allred score. The results were correlated with the presence or absence of liver metastases. RESULTS: The retrospective study included 19 males and 19 females of age 27-79 years (mean 54). Tumor size was 0.9-11.5 cm (mean 3.8). Palladin expression was cytoplasmic and/or membranous. The tumors with high palladin expression were associated with liver metastasis (p<0.0001). All 14 primary PECA with hepatic metastases (MP-PECAs) exhibited palladin expression whereas 14 out of 24 (58%) clinically-localized primary PET (CLP-PETs) expressed palladin (p<0.01) with median Allred scores of 5 (range 3-7) and 2 (range 0-6) respectively (p<0.0001). The mean Allred score for the HNPIs in the MP-PECAs (N=6) was higher (4.2) as compared to that in the CLP-PETs (2.5,N=11) (p=0.23). CONCLUSION: Palladin may identify primary pancreatic endocrine neoplasms with a propensity to metastasize to the liver.

RUNX1T1: a novel predictor of liver metastasis in primary pancreatic endocrine neoplasms.

OBJECTIVES: Using gene expression profiling on frozen primary pancreatic endocrine tumors (PETs), we discovered RUNX1T1 as a leading candidate progression gene. This study was designed (1) to validate the differential expression of RUNX1T1 protein on independent test sets of metastatic and nonmetastatic PETs and (2) to determine if RUNX1T1 underexpression in primary tumors was predictive of liver metastases. METHODS: Immunohistochemical expression of RUNX1T1 protein was quantified using Allred scores on archival metastatic (n = 13) and nonmetastatic (n = 24) primary adult PET tissues using custom-designed tissue microarrays. Wilcoxon rank sum/Fisher exact tests and receiver operating characteristic curves were used in the data analysis. RESULTS: Median RUNX1T1 scores were 2 (2-7) and 6 (3-8) in metastatic versus nonmetastatic primaries (P < 0.0001). Eleven of 13 metastatic and 1 of 24 nonmetastatic primaries exhibited RUNX1T1-scores of 4 or less (P < 0.0001). Low RUNX1T1 expression was highly associated with hepatic metastases (P < 0.0001), whereas conventional histological criteria (Ki-67 index, mitotic rate, necrosis) were weakly associated with metastases (P = 0.08-0.15). Considering RUNX1T1 expression (Allred) score of 4 or less to be predictive, the sensitivity to predict hepatic metastases was 85%, with a specificity of 96%. CONCLUSIONS: RUNX1T1 protein is underexpressed in well-differentiated metastatic primary PETs relative to nonmetastatic primaries and emerges as a promising novel biomarker for prediction of liver metastases.

Primary mixed lymphoepithelioma-like carcinoma and intra-hepatic cholangiocarcinoma: a case report and review of literature.

Primary lymphoepithelioma-like carcinomas (LELC) of the hepatobiliary tract are quite rare and the majority are associated with the Epstein-Barr virus (EBV). Here we report an unusual case of intrahepatic cholangiocarcinoma (ICC), admixed with LELC in a 63 year-old Filipino woman who presented clinically with right flank and back pain. Histologically, the tumor showed a dense lymphocytic infiltrate, predominantly composed of CD3 (+) T cells, and two components: an undifferentiated carcinoma, morphologically similar to nasopharyngeal carcinoma, and a poorly differentiated ICC intimately admixed. Immunohistochemical studies revealed that both components were immunoreactive for AE1/AE3, cytokeratin 7 and, focally, for monoclonal CEA. Both components were negative for cytokeratin 20 and HePar 1. EBER-1 in situ hybridization was uniformly positive in the tumor cells. The presence of EBV in ICC and LELC suggests that the virus may be linked to the pathogenesis of both components of the tumor. The mechanism of virus-driven neoplastic transformation needs further study.

Colonic angiolymphoid hyperplasia with eosinophilia masquerading as malignancy: a case report and review of the literature.

Angiolymphoid hyperplasia with eosinophilia (AHE) of the colon is a rare entity. Since 1997, to our knowledge only 2 similar cases have been documented in the literature. Here, we report a third case that presented as a transverse colonic mass mimicking cancer both clinically and radiologically. Microscopically classic morphologic criteria of this entity were observed, which consisted of both a vascular proliferation and an inflammatory component rich in eosinophils without any malignant features. Whether AHE is a reactive process or a neoplastic process (either a benign vascular neoplasm or a T-cell lymphoproliferative disorder) is still under debate. However, it is important to recognize this entity as a cause of colonic mass to avoid a misdiagnosis of malignancy.