Diagnosis of pancreatic carcinoma by cytology and measurement of oncogene and tumor markers in pure pancreatic juice aspirated by endoscopy

Objective To investigate diagnosis values of pancreatic carcinoma by cytology and measurement of oncogene and tumor markers in pure pancreatic juice(PPJ) aspirated by endoscopy.Methods K-ras point mutation was detected using the polymerase chain reaction and restriction fragment-length polymorphism (PCR-RFLP) in PPJ collected from the pancreatic duct through a nasopancreatic tube put under endoscopic retrograde cholangiopancreatography (ERCP).12 patients had PC and 8 patients had chronic pancreatitis (CP).Results The average PPJ obtained from patients with pancreatic carcinoma and chronic pancreatitis were 86±27ml (56~140ml) and 102±24ml(73~150ml), respectively.The incidences of K-ras point mutation in PPJ was 58.3%(7/12) in patients with PC and 12.5%(1/8) in patients with CP.Meanwhile,cytological examination and CEA measurement in PPJ were performed.Positive cytological results were obtained in 1 of 12 patients of PC (8.3%).The CEA levels of PPJ in patients with pancreatic cancer (49.04±29.07ng/ml) were significantly higher than those with pancreatitis (18.84±12.88ng/ml).K-ras point mutation was found in 73.9%(17/23) of pancreatic tissues surgically resected,and in 10%(1/10) of the adjacent noncancerous tissue.Combining three tumor markers,the sensitivity and specificity of the markers in diagnosing pancreatic cancer rose to 83.3% and 87.5%,respectivity.Conclusion PPJ could be easily and safely obtained using nasopancreatic drainage during ERCP.Combination of K-ras point mutation and the level of CEA,CA19-9 in the PPJ may be valuable for differential diagnosis of the pancreatic cancer from chronic pancreatitis.