Healthcare use and clinical investigations before a diagnosis of ovarian cancer: a register-based study in Denmark

BACKGROUND: Ovarian cancer (OC) is associated with a poor prognosis, which calls for earlier diagnosis. This study aimed to analyse the health care use in primary care and at hospitals among women with OC compared to non-cancerous women to identify a window of opportunity for earlier diagnosis. METHODS: This nationwide register-based observational cohort study included all Danish women aged ≥ 40 years who were diagnosed with a first-time OC or borderline ovarian tumour in 2012–2018 and with no previous cancer diagnosis (n = 4,255). For each case, ten non-cancerous women were identified (n = 42,550). We estimated monthly incidence rate ratios using a negative binomial regression model to assess the use of health care services. We calculated risk ratios of having multiple contacts to general practice before a diagnosis using a binary regression model. RESULTS: Cases had statistically significantly higher contact rates to general practice from five months prior to the diagnosis compared to references. From six to eight months prior to diagnosis, an increased use of transvaginal ultrasound and gynaecologist was seen for cases compared to references. CONCLUSIONS: Increased healthcare use was seen relatively closely to the time of diagnosis for women with OC. This indicates a narrow window of opportunity for a timelier diagnosis. Still, the use of specialised assessment increased at six to eight months before the diagnosis. When women present unspecific symptoms, awareness of potential ovarian malignancies and safety-netting by the general practitioner may be pivotal. TRIAL REGISTRATION: Not relevant. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12875-023-02132-3.