Cancer Research UK said more needs to be done to train and employ people in pathology and other diagnostic areas to meet the growing demand for tests.
As well as analysis of biopsies and blood tests, there is similar rising demand for other cancer tests such as scans and endoscopies, the charity said.
Emma Greenwood, the charity’s director of policy, said: “Diagnostic services, including pathology, urgently need support and investment to ensure that diagnoses aren’t delayed and patients benefit from the latest treatment.
“The UK’s cancer survival is lagging behind other European countries and improving early diagnosis through diagnostic services is one of the ways to address this. The diagnostic bottleneck will only get worse without action now and this involves addressing staff shortages in imaging, endoscopy and pathology.”
The report also calls on the Royal College of Pathologists to update its guidance to increase recruitment to pathology.