Diagnostic application of CD44 variant expression in pancreatic juice for detection of pancreatic neoplasm

Recently, increased and disorganized expression of CD44 variant exons (CD44 v) has been demonstrated in several types of human malignancy. We tried to investigate CD44v expression in pancreatic juice from patients who underwen t endoscopic retrograde pancreatography. We analyzed 24 patients with pancr eatic neoplasms diagnosed histologically (adenocarcinoma, 17; adenoma, 7) a nd 15 patients with non-neoplastic lesions. The expression of CD44v mRNA in pancreatic juice was detected by using the reverse-transcription polymeras e chain reaction technique followed by Southern hybridization with exon-spe cific probes. Of 17 patients with adenocarcinoma, 14 (82%) showed expressio n of CD44v6 mRNA and 11 (65%) showed expression of CD44v2 mRNA. Of 7 patien ts with adenoma, 6 (86%) were positive CD44v6 mRNA expression and 2 (29%) f or CD44v2 mRNA expression; whiled out of 15 patients with non- neoplastic l esion, 5 (33%) showed positive findings for CD44V6 mRNA and 3 (20%) for CD4 4v2 mRNA. Comparing of diagnostic accuracy among CD44v6, CD44v2 and cytolog ical examination, the sensitivities for adenocarcinoma were 82%, 65% and 41 % respectively. However, the specificity was lower in CD44v6 (50%), CD44v2 (77%) than in cytology (100%), because CD44v was positive in adenoma cases and normal cases. A combination of RT-PCR analysis for the expression of CD 44v with cytological examination in the pancreatic juice, may increase the accuracy of diagnosis for pancreatic cancer.