Expression of NeuroD and CD44 in the Fine Needle Aspirates of Pancreatic Endocrine Neoplasms.
Yue Wu, David Chhieng, Yunhua Bao, Guoping Cai. Yale University School of Medicine, New Haven, CT
Background: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been increasingly used in the preoperative diagnosis of pancreatic endocrine neoplasm (PEN). However, it is almost impossible to further classify PENs based on cytomorphologic features alone. There are also no validated markers that can be used for ancillary tests. NeuroD, a member of basic helix-loop-helix transcription factors, may be involved in neural development and differentiation. CD44, a membrane glycoprotein, has been shown to be associated with aggressive behavior, metastasis and poor prognosis in a variety of human tumors. This study is to evaluate expression of NeuroD and CD44 and explore their potential prognostic values in the fine needle aspirates of PENs.
Design: A total of 29 cases of PENs diagnosed by EUS-FNA were retrieved from cytopathology archives at our institution. Surgical follow-ups were available in 14 cases, including 9 cases of well-differentiated endocrine tumor/carcinoma and 5 cases of poorly differentiated/malignant endocrine carcinoma. NeuroD and CD44 immunostains were performed on the cell-block sections. Expression of NeuroD and CD44 were analyzed as percentiles of positive/total tumor cells, which were further compared between well-differentiated and malignant tumor groups.
Results: NeuroD expression with a nuclear staining pattern was seen in all cases of PENs. However, expression of NeuroD was significantly higher in the well- differentiated tumor group (ranging from 75% to 90%) as compared to the malignant group (ranging from 40% to 50%) (p < 0.01). CD44 expression with a membranous staining pattern was seen focally in all PENs (ranging from 5% to 20%) except for one case. Interestingly, the tumor with high CD44 expression (80%) was the only case that had a confirmed distant metastasis (liver).
Conclusions: This study demonstrates that NeuroD is differentially expressed in well-differentiated and malignant PENs and high CD44 expression appears to be associated with a more aggressive behavior, suggesting that NeuroD and CD44 can be potentially used as prognostic markers in the fine needle aspirates of PENs.
Tuesday, March 1, 2011 9:30 AM
Poster Session III # 66, Tuesday Morning