Immunocytochemistry for MUC4, MUC16, NGAL and ECD as an Adjunct in the Diagnosis of Pancreatic Fine Needle Aspiration Cytology.
Adam Horn, Subhankar Chakraborty, Parama Dey, Dhanya Haridas, Channabasavaiah Gurumurthy, Vimla Band, Surinder K Batra, Subodh M Lele. University of Nebraska Medical Center, Omaha
Background: Endoscopic ultrasound guided fine needle aspiration (FNA) of pancreatic mass lesions is a safe method for diagnosis; however, diagnoses rendered as atypical/suspicious for malignancy range from 2% to 29% in various studies. Immunocytochemistry with biomarkers may help in improving sensitivity and specificity within this category. We have identified the expression of four genes, MUC4, MUC16, NGAL (neutrophil gelatinase associated lipocalin) and ECD (ecdysoneless), that are highly upregulated in pancreatic carcinoma as compared to normal pancreatic ducts. In this study, we analyzed their expression in FNA samples in a blinded study at a single center.
Design: Sections from formalin fixed and paraffin embedded cell blocks of FNAs of the pancreas performed at a major tertiary hospital over three consecutive years were reviewed. Unstained sections were immunostained for MUC4 (clone 8G7), MUC16 (clone M11, Dako), ECD (monoclonal), and NGAL (polyclonal) using standard immunohistochemical methods. Anti-MUC4, anti-ECD and anti-NGAL were prepared in our laboratory. Immunostaining was assessed using the H-score (summation of the product of staining intensity and proportion of cells staining). For analysis, any case with an H-score of >0.5 was considered positive. Statistical analysis was done using Medcalc, version 22.214.171.124 for Windows.
Results: The cases were classified using cytomorphologic criteria as carcinoma (57%), benign (9%), atypical/suspicious (20%) and inadequate for immunocytochemistry (14%). On follow-up, all cases diagnosed as carcinoma on cytology were confirmed on biopsy/resection samples. Of the 20% diagnosed as atypical/suspicious, 86% were positive on biopsy/resection and 14% were benign. Overall sensitivity and specificity for the various markers were as follows: MUC4 (72% and 100%), MUC16 (73% and 100%), ECD (85% and 50%) and NGAL (54% and 57%). In cases that were atypical/suspicious on cytology (20%), expression of MUC4, MUC16 and ECD was 100% specific for carcinoma with a sensitivity of 50%.
Conclusions: Immunocytochemistry for MUC4, MUC16 and ECD appears to be a useful adjunct in the classification of pancreatic FNA samples, especially in cases that are equivocal (atypical/suspicious) on cytomorphologic assessment.
Tuesday, March 1, 2011 9:30 AM
Poster Session III # 64, Tuesday Morning