A spokesperson for the HSE said the impact on patients will not be known "subsequent to the resolution of the capacity issue".
Kfm has learned that the HSE was aware of chemotherapy delays as far back as July 31.
Nine out of the 25 hospitals that rely on Baxter Health care to provide Chemotherapy services are impacted.
We have requested a full list of the hospitals in question.
The issue was brought to light when a listener, Ray Noctor, reported that his wife's chemotherapy was delayed without any communication from the HSE.
Ray's wife, Geraldine, was scheduled for treatment at Kilkenny Hospital this week, but it has been postponed due to a shortage of available chemotherapy drugs.
Despite the HSE knowing about the issue for weeks, Ray said they received no notification, leaving them in the dark about when the treatment will resume.
You can read that story here.
A spokesperson for the HSE said the impact on patients will not be known "subsequent to the resolution of the capacity issue".
"The hospitals mainly impacted are those who are completely dependent on outsourcing their compounded Systemic Anti-Cancer Therapy (SACT)," the spokesperson said.
They said the NCCP have communicated to hospitals on the "importance of implementing their local business continuity measures to manage the disruption and minimise impacts to patients’ treatments."
Kfm understands that health chiefs met yesterday to discuss the issue.
You can listen to the full interview with Ray on Monday Morning's Kildare Today at 9.25.