Predictive Value of Symptoms for Early Detection of Ovarian Cancer

Abstract

A consensus statement issued by 3 medical organizations in 2007 recommended the use of certain symptoms of ovarian cancer as early diagnostic markers because they were found much more frequently among women with this cancer than in the general population. The recommendation was in close accord with the findings of investigators who had developed a symptom index that could be useful for early diagnosis of ovarian cancer using the symptoms presumably specific for ovarian cancer. Some investigators, however, have questioned the ability of this approach to detect ovarian cancer at an earlier stage or to improve survival. This population-based case-control study evaluated the positive predictive value of a proposed symptom index and of the specific symptoms identified in the consensus recommendation. The study population comprised of women in Washington State aged 35 to 74 years with primary invasive or borderline epithelial ovarian tumors. The data were obtained by in-depth interviews with 812 women (cases) with ovarian cancer who were in a population-based national registry and 1313 control subjects without ovarian cancer who had been selected randomly. A positive symptom index was defined as the presence (at least daily) of one or more symptoms of pelvic or abdominal pain, increased abdominal size or bloating, and difficulty eating or feeling full lasting a week or longer, with an onset l year or less before diagnosis or a reference date (for the control group). Criteria for the consensus recommendations were considered to be met when any of the aforementioned symptoms or urinary urgency or frequency had been present for at least 1 month, with an onset of less than 1 year before diagnosis or a reference date. External estimates of the prevalence of ovarian cancer were used to calculate the positive predictive value. More than 70% of case patients who had a positive index or who fulfilled the consensus criteria did so within 5 months before their diagnosis. Compared to women with late-stage ovarian cancer, those with early-stage ovarian cancer were less likely to have had the symptoms (except nausea). The positive predictive value of the symptoms in women with early-stage ovarian cancer was less than 0.5% and ranged from 0.6% to 1.1% overall for all ages and all stages of invasive disease combined. These findings indicate that use of the symptom patterns to detect ovarian cancer has low positive predictive value and that this approach would be able to diagnose the tumor in only 1 of 100 women in the general population.