Unusually High Serum Levels of CA 19-9 in an Ovarian Tumour: Malignant or Benign?

Carbohydrate antigen 19-9 (CA 19-9) is a tumour marker found to be elevated in some ovarian tumours. We share our experience with a 55-year-old postmenopausal lady with unusually high CA19-9 levels arising from a benign mucinous cystadenoma of the ovary. The levels returned to normal eight weeks following staging laparotomy and a total abdominal hysterectomy with bilateral salpingo-oopherectomy. This report shows rare and significant elevation of CA 19-9 levels with benign mucinous cystadenomas of the ovary thus showing that women with unusually elevated tumour markers may actually harbour benign disease. The tumour markers should not be used to predict the malignant status of a tumour.