Cancer diagnoses may be delayed due to coronavirus, a leading Northern Ireland health charity said.
It could mean patients require more treatment, Roisin Foster, Cancer Focus NI chief executive, added.
Routine screening has been postponed to allow medics to focus on tackling the infection.
Surgery, chemotherapy and radiotherapy are among options often considered by doctors after the disease is diagnosed.
Ms Foster said: “Screening is being paused for other clinical reasons.
“It does mean that some people will have their cancer diagnosed later than they would have.
“That may mean that they have to have more treatment.
“It may well have advanced.
“It is just storing up problems for the future.”
She said most women who attended breast screenings would receive a clear result but it was more important now that people checked for lumps and other warning signs and if concerned went to their doctors.
She added some treatments were being delayed on a case-by-case basis due to the risk of coming into hospitals and potentially catching the virus as well as stretched services.
The chief executive said the impact of the pandemic on patients’ state of mind was heart-breaking.
“When you get a cancer diagnosis you are worrying constantly about whether the treatment will work and will you ever feel or look the same again.
“On top of that is imposed all the worry about the impact of coronavirus.”
The virus is particularly dangerous to patients with compromised immune systems like those undergoing some cancer treatments.
Programmes affected include routine cervical, breast and bowel cancer screening.
Higher risk breast screening and smear tests for non-routine cervical screening like repeats requested by colposcopy or the laboratory will continue to take place.
Health Minister Robin Swann said: “I know the importance of screening, but this decision will allow reallocation of precious resources to our frontline staff as they undertake the massive task ahead of them.
“In addition it must be remembered that many people who attend screening programmes are in a higher-risk category for coronavirus and it is essential that we minimise risk to those people through maintaining social distancing at this time.”
It follows the suspension of non-urgent outpatient appointments and non-urgent surgical admissions.
Cancer Focus NI has been in operation for half a century in Northern Ireland.
It provides care and support for patients and their families and offers a range of prevention programmes.
The charity also funds scientific research into the causes and treatment of the disease and campaigns for better health policy.