Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data

This is the first study to examine the clinical significance of thrombocytosis as a marker for cancer in all cancer types in primary care. Using a prospective cohort study with nearly 40,000 patients they identified that thrombocytosis was most common in lung and colorectal cancers compared to the general population. The overall risk of cancer, positive predictive values, in patients with thrombocytosis was: 11.6% in males and 6.2% in females compared to 4.1% and 2.2% in each gender with normal platelet counts. These results are well above the current 3% risk threshold used for urgent investigation of suspected cancer in the UK. The authors suggest that if only 5% of patients with thrombocytosis have cancer before diagnosis one-third of these people, approximately 5500 people, have the potential to have their diagnosis expedited by at least 3 months; if this condition was used routinely investigated in primary care.   Read the full article here.