(P-568) Limited Time Interval Between Symptomatic Presentation in Primary Care and Colorectal Cancer Diagnosis

Background: Timely recognition of colorectal cancer related symptoms is essential to reduce time to diagnosis.

Objectives: This study aims to investigate the primary healthcare use preceding a colorectal cancer diagnosis.

Methods: A population-based case-control study was conducted using data from a cohort of linked data from the Netherlands Cancer Registry (NCR) and the PHARMO General Practitioner (GP) Database (NCR-PHARMO GP cohort). Primary healthcare use among colorectal cancer cases before diagnosis was compared with matched cancer-free controls. Information on primary health care use was derived from the GP Database of the PHARMO Database Network and included all GP consultations and prescribed medication. Mean monthly number of GP consultations and new drugs users was assessed in the year before index date (diagnosis date for cases). Results were stratified by colorectal cancer site: proximal colon cancer, distal colon cancer and rectal cancer.

Results: While mean monthly number of GP consultation were stable through the year among cancer-free controls, a statistical significant increase was seen among colorectal cancer cases in the last 4-8 months before diagnosis. Proximal colon cancer cases showed the longest time interval of increased mean monthly number of GP consultations. This increase was largely driven by a consultation for malignant neoplasm colon/rectum. The number of new drug users was stable around 120 per 1,000 persons per month until 8 months before index date for proximal colon cancer cases, 4 months before index date for distal colon cancer cases and 3 months for rectal cancer cases. This increase was mainly driven by the prescription of laxatives drugs.

Conclusions: A relatively short time interval of increased GP consultations and new drug users was seen before colorectal cancer diagnosis. The longest period of increased GP consultations and new drugs users was seen among patients diagnosed with proximal colon cancer. This can be explained by the difficultly to diagnose proximal colon cancer given the more subtle signs compared to distal colon cancer and rectal cancer. Therefore, faster diagnosis for this specific tumour subtype is only possible when clear clinical signs and symptoms are present.