It follows the admission on Monday by health bosses there that patients had been given lower-than-standard doses of the drug Docetaxel, which can prevent the spread or return of breast cancer, since December 2016.
The health board has said it is “really sorry” to all patients and families affected, and politicians have called for an “urgent” public inquiry into why Tayside patients received a lower dose of chemotherapy treatment than those elsewhere in Scotland.
A report on the issue by Healthcare Improvement Scotland (HIS) revealed nurses and pharmacists working for the board shared fears that patients were not being consulted about the lower dose.
The report also said NHS Tayside breast oncologists and their contemporaries at NHS Highland and Grampian could not agree on dosing levels, with Tayside doctors not willing to “endorse” using a higher dose, while Grampian and Highland doctors failed to sign off on the guidelines unless the higher dose was available.
As the guidelines were being drafted, the Tayside oncologists asked for two bullet points regarding dosing levels to be removed, without “providing the rationale” for doing so.
North East Labour MSP Jenny Marra said: “There should be a public inquiry established with urgency to clarify why this situation was allowed to happen and went unchallenged until a whistleblower had the courage to speak out.
“Serious questions need to be asked of the doctors and management at Ninewells.
“I was also shocked to read that there was no attempt to rectify or change dosages after the issue had been raised.
“Staff said they were in ‘lockdown’ and had to continue to give low dosages of chemotherapy. This is a serious question for NHS management as patients were being treated with low dosages while an investigation was under way.”
Shona Robison, MSP for Dundee East, was cabinet secretary for health when the issue was first raised with the board.
She said: “Families of those who have died need answers and reassurances. I welcome an independent review. This could be the quickest and best way to get the answers that people are looking for.
“I was deeply concerned when I discovered what had happened and that is why I got involved in having this issue reviewed.”
Professor Peter Stonebridge, acting medical director at NHS Tayside, said: “We have taken action to rapidly change our approach to breast cancer chemotherapy, ensuring it is in line with practice across the rest of Scotland.”