Cancer charities have warned waiting times are "spiralling upwards" and will have a "devastating" impact on those waiting for treatment.
One charity said "our heart goes out to people who are worried that they have not yet been able to get a diagnosis and to those who are waiting for their treatment to begin or resume".
It comes after statistics reveal that from January to March, the percentage of patients with an urgent GP referral for suspected cancer starting treatment within 62 days was just 49 per cent - the target is 95 per cent.
All health trusts missed the target for the quarter.
An additional report which outlines cancer waiting times for April, reveals the percentage of patients seen within the target of 62 days following an urgent GP referral fell by eight per cent compared to the same month last year.
It also emerged yesterday that 850 women are awaiting breast cancer screening in the north. They had been due to be seen in March before the coronavirus lockdown.
Stormont health minister Robin Swann said it was "a stark reminder of the massive challenges that face the health care system in Northern Ireland".
He said the statistics "illustrate the vital necessity of a major overhaul of how we provide health care across all disciplines".
"The restructuring of services necessitated to combat Covid-19 means that the waiting lists for the second quarter will in all likelihood be even worse," he said.
Margaret Carr from Cancer Research said the figures "paint a worrying picture of the impact of Covid-19 on cancer services".
"Unfortunately, in future, we’re likely to see an even more significant increase in cancer waiting times," she said.
Janice Preston from Macmillan Cancer Support as called on the Assembly to "urgently restore cancer services and prioritise care".
"Even before the significant impact of coronavirus, too many people in Northern Ireland have faced anxious delays to get a cancer diagnosis and start treatment because our health and social care system has not been fit for purpose, despite the efforts of hard-working healthcare professionals across all of our trusts," she said.
Dervilia Kernaghan from Cancer Focus NI said: "It is extremely concerning to see waiting times spiralling upwards and our heart goes out to people who are worried that they have not yet been able to get a diagnosis and to those who are waiting for their treatment to begin or resume.
"We must take action now to recover from the delays caused by Covid-19 and also to improve on the inadequate waiting times that existed before."
