PROTOCOL: Thrombocytosis: an underused risk marker of cancer in primary care?

Abstract

Background: The UK does very badly in cancer, and any way of diagnosing it more quickly would be welcomed. The UK has a poor record in cancer outcomes, much of which is blamed on delays in diagnosis. Many initiatives have been established to help primary care identify and investigate patients with possible cancer. One factor which has received little attention is a raised platelet count (thrombocytosis). Our team has identified this as being relevant in lung, colon, ovary, oesophago-gastric, bladder and pancreas cancers. Together, these six cancer sites suggest that the risk of an underlying cancer in a patient with thrombocytosis exceeds 4% and may be as high as 10%. Such a figure would make a very important contribution to cancer diagnosis: a contribution that is currently completely absent from current diagnostic practice.