Findings of a new study suggest that a very high platelet count might indicate investigation for an occult cancer

Cancer cells illustration_Design Cells_208548344

A new study published in JAMA Network Open suggests individuals with a high platelet count might warrant investigation for an occult cancer, particularly if other non-malignant causes have been ruled out.

The nested case-control study included residents in Ontario, Canada, who had at least one routine full blood count performed between 1 January 2007 and 31 December 2017, with follow-up through 31 December 2018.

Of 8,917,187 eligible participants, 495,341 (5.6%) received a diagnosis of first primary cancer during the 10-year observation period.

Of individuals who had a cancer diagnosed within 6 months after the blood test, 19.5% had a very high platelet count.

The odds ratio (OR) for a solid tumour diagnosis associated with a very high platelet count versus a medium platelet count in the 6 months before diagnosis was 2.32 (95% CI 2.28–2.35).

A very high platelet count was particularly associated with colon (OR 4.38; 95% CI 4.22–4.54), lung (OR 4.37; 95% CI 4.22–4.53), ovarian (OR 4.62; 95% CI 4.19–5.09), and gastric (OR 4.27; 95% CI 3.91–4.66) cancer.

The association weakened as the time between blood test and cancer diagnosis increased.

The research team now plans to investigate the clinical utility of platelet count testing as a screening tool.

This article was originally published on Univadis, part of the Medscape Professional Network.


Lead image: Design Cells/

Image 1: Design Cells/