Early symptoms of ovarian cancer: a case-control study without recall bias

Background. Ovarian cancer is usually diagnosed after it has spread and is difficult to cure. Previous attempts to identify early symptoms have either lacked a control group or have been based on interviews of cases, with possible recall bias. Objective. The purpose of this study was to identify early symptoms of ovarian cancer by reviewing prediagnostic medical records, free of recall bias, and comparing women with and without ovarian cancer. Methods. In an integrated health care delivery system, symptoms recorded in medical records of 102 women with ovarian cancer during the two years before diagnosis were compared with those of 102 matched control women. Results. More cases than controls complained of several symptoms up to one year before diagnosis. Most of these symptoms were abdominal or gastrointestinal in nature and were more prevalent in the advanced stage cases. Other symptom sites included pelvic, urinary, back, and systemic. Because case-control differences were not large and prevalence is low, positive predictive values were generally quite low. Conclusion. Previous reports of early symptoms of ovarian cancer were confirmed in a study with a control group and free of recall bias. It is not clear that these symptoms occurred while the disease was still localized. Because hundreds of women would have to be investigated to detect one case of ovarian cancer, the clinical utility of these symptoms is uncertain. Nevertheless, health care providers should keep ovarian cancer in mind, when women present with symptoms such as abdominal pain and bloating.