On Friday afternoon, the Southern District Health Board said the MDM sessions had been split in two to allow clinicians more time, although it could not say when this occurred.
The issue was described as still under review in the board's 2011-12 "serious and sentinel" events report last week.
The draft and final reports into the mastectomy mistake have been released to the Otago Daily Times.
They include recommendations from Southern Community Laboratories (SCL).
A patient had an unnecessary mastectomy in March after her specimen was swapped with another patient's specimen. She was incorrectly diagnosed with invasive pleomorphic lobular carcinoma, the realisation of which about a week after the surgery led to immediate changes in how SCL handled specimens.
Patient services executive director Lexie O'Shea said through a spokesman on Friday that tumour and screening cases had been split into separate sessions. The spokesman did not know when this happened.
The woman's MRI results following the false positive biopsy were clear, after which the MDM still approved a mastectomy.
Offering a mastectomy and sentinel lymph node biopsy was the "safest course" in the circumstances, the report said.
Patient services medical director Dick Bunton told the ODT MRI was not as indicative as the mammogram that first raised concern.
The MRI result was "irrelevant", Mr Bunton said.
SCL's concerns about MDMs did not relate to that decision, he said.
In the June 12 draft and the final report, SCL expressed concern about the meetings.
"MDMs are often under considerable time pressure and usually run for 90 minutes and occasionally even up to 120 minutes.
"Consideration should be given to streamlining these meetings because, due [to] the number of cases, they can be too long.
"It is noted that the pathology findings are usually only a minor component of the time taken up, but where there is discrepancy the pressure of getting through the meeting must not compromise the completeness of the MDM discussion."
While some of this section was removed in the final report, one of the final recommendations is ensuring clinicians have enough time for each case, which the board said it had achieved.
Another of the lab's suggestions was completely removed from the final version.
The lab said fine needle aspiration cytology (FNAC) had "essentially ceased locally" as a diagnostic tool for breast cancer.
Using FNAC gave results equivalent to core biopsy at less cost, and less patient discomfort, the lab said.
In response, Mr Bunton said this was taken out because such thinking did not agree with the national position on FNAC. The statement was a "laboratory-centred view" on diagnostic procedures and did not reflect the views of clinicians.
The Dunedin case, and four others nationally, sparked a Ministry of Health national inquiry this year.
The inquiry identified MDMs as a key opportunity to pick up inconsistencies in test results, challenge assumptions and question diagnoses.
The ministry published new guidelines for MDMs shortly after the breast panel reported back in September.
