Patient given double radiation dose in error at Edinburgh Cancer Centre
A cancer patient was mistakenly given double the dose of radiation required for their treatment, a new report has revealed.
Two radiographers at the Edinburgh Cancer Centre both incorrectly calculated the amount of radiation to be given when the patient was being treated for multiple myeloma – a type of bone marrow cancer.
The patient, who has not been identified, was prescribed radiotherapy as part of their palliative care.
But a report for Scottish ministers said “the dose received was 100% greater than the intended dose”.
It comes 10 years after teenager Lisa Norris, from Girvan in South Ayrshire, was given an overdose of radiation whilst undergoing treatment for brain cancer at the Beatson Oncology Unit in Glasgow and subsequently died.
In the report, Dr Arthur M Johnston, the warranted inspector appointed by Scottish ministers, said the overdose of radiation given to the patient at the Edinburgh centre in September 2015 was more severe.
He stated: “It is approximately 10 years since I was last called upon to undertake a detailed investigation of an incident involving a serious overexposure to ionising radiation for a patient undergoing radiotherapy.
“That earlier investigation was the overexposure of Miss Lisa Norris at the Beatson Oncology Centre in Glasgow, who was being treated for a pineoblastoma, from which, tragically, she subsequently died at the age of only 16.”
While Miss Norris received radiation amounting to “58% greater than the intended dose”, Dr Morris: “In this case, the treatment delivered at the Edinburgh Cancer Centre (ECC) was a palliative radiotherapy treatment for alleviation of pain and existing disability in an older patient, and the dose received was 100% greater than intended dose.”
He added: “In both instances, the extent of the overexposure was such that there was a significant possibility of serious harm to the patient.”
A Scottish Government spokeswoman said: “We extend our thoughts and sympathies to the patient and their family, who have been affected by this incident.
“While these incidents are extremely rare, it can be very serious if any patient is overexposed to radiation and so it is right that procedures at the Edinburgh Cancer Centre were fully, and independently, investigated.
“NHS Lothian and the Edinburgh Cancer Centre have taken a number of steps to change practice and minimise the risk of an incident like this happening again.
“We expect the health board to take forward all of the recommendations in the report and progress will be monitored closely by the inspector.”
NHS Lothian said patient confidentially means it cannot reveal any details about the patient, including whether they are still alive.
The radiotherapy treatment was “properly prescribed”, according to the report, but it added: “Errors were made in the subsequent process of planning how the prescribed treatment was to be delivered.”
These “remained undetected” and as a result, the setting used on the treatment machine was “twice what it should have been, and remained so for all five ‘fractions’ of the treatment process”.
The report revealed one radiographer had “made an error in the depth-dose calculation to the extent that the calculated doses to each side of the neck entered in the Radiotherapy Prescription Sheet were 100% too high”.
In line with protocols, a second radiographer carried out a similar manual calculation, but the report said they “made the same mistake, and got the same wrong answer”.
A programme used to electronically check prescribed doses, “flagged correctly that the manually calculated dose was incorrect”, the report said.
But it added that the “erroneous belief” of the four radiographers involved was that “the manual calculations were correct, and the computed result was in error”, and that as a result “the manual calculation was not rechecked”.
The error was only identified 11 days after the patient completed the treatment.
In the report, Dr Johnston said “I am conscious of the potential for the content of this report to add to the concerns of those undergoing radiotherapy treatments at the ECC and elsewhere.
“In this regard I should note that lessons have been learned and changes implemented at the ECC, and that I have confidence in the dedication of the commitment of ECC staff to the safety of patients in their care.
“I would again acknowledge the many thousands of life-saving radiotherapy treatments that are successfully prescribed, planned and delivered at the ECC and at the other radiotherapy centres in Scotland every year.”
Dr David Farquharson, medical director at NHS Lothian, said: “We offered our most sincere apologies to the patient and their family following this very unusual and deeply distressing incident. Since then, we have ensured that they have been kept informed throughout the full and thorough investigation and reporting stages of the process.
“Cases such as these are thankfully very rare, but as soon as it was identified we implemented a series of measures to minimise the risk of a similar incident. We carried out a robust internal investigation and immediately informed the external inspector.”
He continued: “We fully accept the findings of the report and an action team has been created to ensure that each point will be implemented as a matter of urgency, if it has not already been identified during our own investigations.”
The investigation “identified a number of mistakes made by the operators concerned in both the manual and electronic calculations involved”, the report said, adding that given the level of experience of the staff involved “it could reasonably be expected that the errors involved should have been identified prior to treatment”.
Conservative health spokesman Donald Cameron said: “This was an awful incident and our thoughts are with the patient, their family and friends.
“We need proper assurances from the health board and (Health Secretary) Shona Robison that this mistake will never happen again.”
Copyright (c) Press Association Ltd. 2016, All Rights Reserved. Picture (c) Peter Byrne / PA Wire.
