Coronavirus: Big drop in cancer referrals in Wales
The number of patients referred for cancer treatment in April dropped by more than 51% compared to the previous month, according to official figures.
People with possible symptoms have been urged not to put off getting them checked out during the pandemic as part of a new Welsh Government campaign.
Swansea Bay health board, where referrals were down 52%, attributed it to a fear of visiting hospitals or GPs.
Charities have warned of a cancer "timebomb" due to Covid-19 disruption.
Figures published by the Welsh Government show 4,913 patients entered the single cancer treatment pathway in Wales in April.
That is a drop of 5,118 patients from March.
The figures include all those starting treatment during the month and those already on the pathway.
Powys saw only five referrals, compared to 29 in March.
In the Aneurin Bevan health board area - which was a coronavirus hotspot early on in the pandemic - there was a 60% fall.
The reporting of a single pathway for cancer patients came in last summer and counts people from the moment cancer is suspected not just when a hospital receives their referral from a doctor.
It aims to speed up diagnosis and improve survival rates for 17,600 people who get the disease every year in Wales.
Also in April, 1,240 patients newly diagnosed with cancer were treated through the single cancer pathway. This is a drop of 26.7% (452 patients) from March.
Cancer charity Macmillan has warned Wales, like the rest of the UK, is facing a potential "cancer timebomb" due to the disruption to diagnosis, treatment and care caused by Covid-19.
The Welsh Government acknowledged services had been hit during the pandemic but it said the number of referrals was improving.
Health Minister Vaughan Gething said: "Tests and treatment for cancer are available and I want those who need to seek care and treatment to continue to do so."
Meanwhile, there was an increase in people using A&E units in May but this is still "far lower" than before the pandemic hit, with attendances down by more than a third on last year.