The Cancer Agency has revealed the allegations of "cancer cluster" in the Ulster University campus (UU) campus, BBC News NI found out.
The Cancer Registry (NICR) did not show enough evidence that UU's Jordanstown campus was responsible for any prostate cancer among the staff.
The university says the campus is safe for staff and students.
But she also said that no employee can now be permanently based in this area.
The area – the lower part of the seventh block in Jordanstown's main building – was not used by students.
At any time there were about 35 employees working at the Information Technology (IT) department at the University.
& # 39; Several Cancer Diagnosis & # 39;
The NICR investigation was initiated by a former staff member who approached the registry.
There was concern that "several diagnosed carcases" among people "working in this area in recent years".
After the NICR contacted the university in July, he immediately switched all staff from the block.
While the NICR investigation was ongoing, UU also conducted 26 separate studies on environmental factors, including ionizing radiation, asbestos and electromagnetic radiation.
Director of People and Culture of the University Damian McAlister told BBC News NI that the health and wellbeing of staff is her primary concern.
"I specifically think of those staff who are currently ill and their families," he said.
"All of these tests have returned safe results that indicate that there are no ecological factors at this stage that we know it will cause cancer that has been reported to our staff."
Mr. McAlister also said he contacted 65 current and former employees working in the area to meet them with the problem but also to invite them to participate in the cancer record.
He added: "Of those 65, 29 employees have given their consent for their data to be sent confidentially to the cancer register."
"Accidentality of Coincidence"
NICR findings have been reported to staff this week, and are received by BBC News NI.
The report states that "rates of cancer incidence" among employees working in one office in this area were "higher than the average of Northern Ireland".
But he found "insufficient evidence to support the hypothesis that higher rates in a smaller office space are the result of external environmental factors."
"A small number of cases and a lack of apparent relationship between types of cancer diagnoses suggest that all differences are likely to result from chance, life style, or genetic factors."
The University and College Unity (UCU), which represents some staff, said she "greeted the NICRs with great care" but expressed concern about the size of the study sample.
"It is quite possible that the results could be more or less worrying if some of those who were potentially affected agreed to cooperate with the cancer register," said trade union Katharine Clarke.
She said UCU would encourage staff working in that area to contact the registry to help "establish more persuasive and reliable findings".
The University has decided that the area will primarily be used for storage in the future.