Safia N. Salaria

PD-1 Inhibitor Gastroenterocolitis Case Series and Appraisal of “Immunomodulatory Gastroenterocolitis”

PD‐1 inhibitors facilitate immune response against certain tumour types, including melanoma. These drugs have led to prolonged survival but can also result in autoimmune‐type side effects, including gastrointestinal inflammation. The histopathological effects of this medication class have not been well studied.

Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine neoplasms include well-differentiated pancreatic neuroendocrine tumors (PanNETs) and neuroendocrine carcinomas (NECs) with well-differentiated PanNETs accounting for most cases. Other pancreatic primaries and metastatic carcinomas from other sites can mimic pancreatic neuroendocrine neoplasms. Immunohistochemical studies can be used to aid in the differential diagnosis. However, no specific markers are available to differentiate PanNETs from NETs of other sites. Although NECs are uniformly deadly, PanNETs have variable prognosis. Morphology alone cannot predict the tumor behavior. Although some pathologic features are associated with an aggressive course, Ki67 is the only prognostic molecular marker routinely used in clinical practice.

Expression of CD24, a Stem Cell Marker, in Pancreatic and Small Intestinal Neuroendocrine Tumors

OBJECTIVES CD24 has been considered a normal and cancer stem cell marker. Potential intestinal stem cells weakly express CD24. In the pancreas, CD24 is a possible cancer stem cell marker for ductal adenocarcinoma. METHODS Expression of CD24 in intestinal and pancreatic neuroendocrine tumors (NETs) was examined. Immunohistochemistry was performed on benign duodenum, ileum mucosa, and pancreas, as well as primary duodenal, primary and metastatic ileal, and pancreatic NETs. RESULTS Scattered CD24-positive cells were noted in the duodenal and ileal crypts, most of which showed a strong subnuclear labeling pattern. Similar expression was observed in 41 (95%) of 43 primary ileal NETs but in only four (15%) of 26 duodenal NETs (P < .01). In addition, metastatic ileal NETs retained CD24 expression. Pancreatic islets did not express CD24, and only rare cells had subnuclear labeling of CD24 in the pancreatic ducts. Unlike ileal NETs, only five (5%) of 92 pancreatic NETs expressed CD24 in the subnuclear compartment (P < .01). All five NETs showed a unique morphology with prominent stromal fibrosis. CONCLUSIONS CD24 expression was frequent in primary and metastatic midgut NETs but rare in pancreatic and duodenal NETs. Expression of CD24 in ileal NETs may have future diagnostic and therapeutic implications.

Correction to: Phase I study combining the aurora kinase a inhibitor alisertib with mFOLFOX in gastrointestinal cancer

The authors would like to note that the investigator affiliations have been corrected to reflect the actual affiliations of each author. The authors would also like to note an amendment to the first name of the second author. Nilo Azad was changed to reflect the full name of the author, which is Nilofer S. Azad as shown above. The original article has been corrected.

The association of HGF/Cmet overexpression with clinicopathologic factors in hepatocellular carcinoma.

297 Background: The Cmet receptor tyrosine kinase is overexpressed in 20-50% of hepatocellular cancers (HCC) and has been associated with aggressive features. Little is known about the clinical characteristics of patients whose tumors overexpress Cmet. We examined Cmet expression levels on a series of 80 HCC samples to evaluate for an association between overexpression and clinicopathologic features. Methods: Samples from 80 patients with HCC were assessed with immunohistochemistry (IHC) analysis for hepatocyte growth factor (HGF) and Cmet. Positive staining was correlated with age, sex, race, HCC risk factors, tumor grade, stage, metastatic sites and survival. Results: Hepatitis B virus (HBV) patients were more likely to have Cmet positive tumors than those with other risk factors for HCC such as hepatitis C or alcohol. Higher tumor grade was associated with Cmet positivity. No evidence of association between Cmet positivity and survival was seen although HGF positivity tended to associate with a trend t...