Routine blood tests and probability of cancer in patients referred with nonspecific serious symptoms: a cohort study

As Danish cancer patients have a lower survival rate than patients in many western countries, an urgent referral pathway for patients with non-specific, serious symptoms was implemented throughout Denmark in 2011-12. A panel of blood tests are performed for all patients referred by their GP to the urgent referral pathway and this study investigates the probability of being diagnosed with any cancer in GP-referred patients with abnormal blood test results. Of the 1499 patients who were referred by their GP to Silkeborg Regional Hospital, 12.2% were subsequently diagnosed with cancer. The probability of cancer increased with the number of abnormal blood tests and patients with specific combinations of two abnormal blood tests had a 23-62% probability of cancer. However, only a few single abnormal blood tests were link with a high probability and most were not specific to cancer. This study shows that the information derived from a number of specific abnormal blood tests markedly increased the probability of finding cancer, although none of the abnormal blood tests were specific to cancer. Read the full article