Background: Serum CA 19-9 is the mainstay marker for the diagnosis of biliopancreatic malignancies, though a persistent elevation can also be observed in various benign diseases.
Aims: In this study, a marked increase of serum CA 19-9 was seen in 10 patients who had no evidence of malignant disease. The possible causes of this finding are discussed.
Patients: Nine women and one man were studied, whose admitting diagnoses were as follows: pulmonary fibrosis in two, diabetes in two, non-ulcer dyspepsia in two, obesity in one, acute diarrhoea in one, colon diverticula in one and gastric ulcer in one.
Methods: Routine blood tests, tumour marker determinations, imaging studies and endoscopy were carried out at admission.
Results: Serum CA 19-9 levels ranged from 112 to 1338 IU/ml (mean 517 IU/ml). Abdominal ultrasonography, CT-scan, upper gastrointestinal X-ray series and gastrointestinal endoscopies were negative for malignancy. During the follow-up period (range 2-7 years) serum CA 19-9 values were persistently elevated in all patients.
Conclusions: Our study shows that persistent and significant elevation of serum CA 19-9 can be found in non-malignant and non-cholestatic disease.