Objective: Mucinous cystic tumours of the pancreas need to be distinguished from other cystic lesions because of their malignant potential. The aim of this study was to assess prospectively the reliability of CA 72-4 and carcinoembryonic antigen analysis in the fluid of cystic lesions of the pancreas obtained by fine-needle aspiration for pathological diagnosis.
Methods: CA 72-4 and carcinoembryonic antigen were measured in cyst fluid obtained preoperatively by fine-needle aspiration. The 91 lesions consisted of 16 serous cystadenomas, 16 mucinous cystadenomas, 14 cystadenocarcinomas and 45 pancreatic pseudocysts complicating well documented chronic pancreatitis.
Results: A CA 72-4 level of >40 U/ml had a 63% sensitivity and 98% specificity for distinguishing mucinous cystadenomas and cystadenocarcinomas from serous cystadenomas and pseudocysts. A carcinoembryonic antigen level of >400 ng/ml had a 57% sensitivity and a 100% specificity for distinguishing mucinous tumours and cystadenocarcinomas from pseudocysts. A carcinoembryonic antigen level of <4 ng/ml had a 100% sensitivity and a 93% specificity for distinguishing serous cystadenomas from mucinous cystadenomas, cystadenocarcinomas and pseudocysts.
Conclusion: Combined measurement of CA 72-4 and carcinoembryonic antigen may be used to distinguish accurately mucinous cystadenomas and cystadenocarcinomas from serous cystadenomas and pseudocysts.