Elevated serum alkaline phosphatase may enable early diagnosis of ovarian cancer.

A case of endometrioid ovarian carcinoma associated with elevated levels of serum placental-like alkaline phosphatase (PLAP) is presented. Two and a half years before a final diagnosis was made following explorative laparotomy, an incidental blood test revealed elevated alkaline phosphatase in the patient's serum. A thorough investigation for the source of this elevation was negative. Postoperative immunohistochemical staining of the tumor, showed diffuse stain with PLAP, along with gradual decline to normal values of serum total alkaline phosphatase. It is suggested, that whenever serum alkaline phosphatase is elevated due to unknown reason, an investigation including alkaline phosphatase isoenzymes, serum Ca-125, trans-vaginal pelvic sonogram and even diagnostic laparoscopy, should be considered in a search for early preclinical ovarian cancer.