Tenovus Cancer Care says cancer services across the country have been put under huge pressure with resources diverted to tackle the Covid-19 outbreak and staff members off work with infections and self-isolation.
On Tuesday the charity said the Welsh Government should introduce a national plan to ensure vital cancer surgeries can continue and delayed surgeries and screenings are carried out at the earliest opportunity when restrictions are lifted.
I've spoken to leading cancer clinicians who believe hundreds, possibly several hundred, cancer patients could die in Wales because of delays in treatment and screening with NHS and private care providers who are dealing with the Covid-19 crisis.
Mrs Rhys said people who suspect they have cancer symptoms will , and said the disruptions meant that assurances given by Wales' health minister Vaughan Gething that cancer treatment would continue during the pandemic was "clearly no longer the case".
Mrs Rhys added: "We now need the Welsh Government to set out an honest, clear plan for cancer care for those needing treatment now and in the months ahead."
A Welsh Government spokesperson said: “The safety and welfare of staff and patients is our priority. We are working with the NHS in Wales to ensure urgent treatment, including for cancer, is maintained during the pandemic. We are taking urgent measures to increase hospital and critical care capacity.”
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