Specialist physicians in Quebec question why the outside review of ER and HER2 breast cancer pathology test results used a 1% standard versus a 10% standard
Public debate in Quebec about inaccurate tests for breast cancer by the province’s pathology laboratories has turned attention to an area of pathology testing which is seldom discussed in public forums. It is the situation where there is often significant variability in rate of false positives and false negatives reported by different pathology laboratories performing the same tests for breast cancer and other diseases.
Quebec’s media coverage about problems with its pathology laboratories and inaccurate breast cancer tests was reported last week by Dark Daily in the e-briefing titled “PART ONE: More Debate in Quebec about How Pathology Labs Performed Inaccurate Breast Cancer Tests” . Here in Part Two, we describe how Quebec’s medical specialists are calling attention to another source of problems. This is how the use of various standards for evaluating breast cancer specimens can contribute to different rates of false positive and false negative results on pathology tests reported by pathology laboratories in the province.
Gaétan Barrette, M.D., President of the Quebec Association of Medical Specialists, speaks at the December 17 press conference about concerns with the review of inaccurate breast cancer tests. (photo © CTV, Canada)
Quebec’s public discussion centers around the original pathology analysis for estrogen receptor (ER) or HER-2 marker status by immunohistochemistry (IHC) for 2,856 cases of breast cancer performed by pathology laboratories in Quebec between April 1, 2008, and June 1, 2009. As noted in the Part One e-briefing, the Quebec Ministry of Health engaged PhenoPath Laboratories of Seattle, Washington, to conduct an outside review of these 2,856 cases.
When Quebec Health Minister Yves Bolduc announced the results of PhenoPath’s review, he stated that 87 women had received a false negative result. Of this number, Bolduc said that 39 women needed to alter their breast cancer treatment because of the new findings. Of the group of 39 women, five have already died. No data on the number of false positive results identified as part of this study appear to have been made public by the Quebec Health Ministry.
Bolduc, who is a physician, stated that the error rate of 1.4% was excellent and observed that this is much below the international standard of 10%. A reporter working for The Canadian Press quoted Bolduc as saying “our laboratories of a very high quality…Our results in pathology, in Quebec, are world-class.”
The response to these events is the twist that pathologists and pathology laboratory managers will find particularly interesting. Specialist physicians in Quebec questioned the standard of accuracy used to conduct the review of the 2,856 breast cancer cases. This question was raised in a press conference on December 17, 2009, conducted by Gaétan Barrette, M.D. He is currently President of the Quebec Association of Medical Specialists (FMSQ).
Barrette, on behalf of specialist physicians in the province, spoke out publicly to question the accuracy standard used by the Quebec Ministry of Health to review the 2,856 breast cancer cases. As part of the press conference, FMSQ issued a press release and said:
The FMSQ is, however, disappointed that the detection threshold selected was so high that that one wonders why it was even considered. In fact, the great majority of patients whose [estrogen receptor] results ranged from 1% of positive cells to the 10% threshold stated at this morning’s press conference by the Minister and his experts, Drs Bernard Têtu and André Robidoux, could benefit from an adjustment to their treatment in the same way as the 87 patients identified so far.
The pathology profession should be aware of where this debate may lead. It was back in June when Barrette made a more sweeping indictment about the accuracy of cancer testing by pathology laboratories in Quebec. In a story published June 2, 2009, reporter Charley Fidelman of The Montreal Gazette wrote about Barrette’s criticism of inaccurate pathology results:
Gaétan Barrette, who heads Quebec’s federation of medical specialists, warned that breast cancer is just the tip of the iceberg. When Gaboury announced the study result showing a 30% variance between pathology labs, Barrette warned that all cancer testing–bone, pancreas, liver, lung—is at risk of such errors.
In a telephone interview, Barrette remained categorical that he was not exaggerating that all cancer tests in Quebec have to be redone: “I stand by what I said. The study was about the process. It’s wrong in one area, why should we conclude that it is right in another?”
Or put it this way, Barrette said: “Why would the Quebec College of Physicians demand quality control if there wasn’t a problem?”
These comments illustrate the degree of concern Quebec’s specialist physicians have about this matter. Independent of the assurances of the Quebec Minister of Health—who must manage public opinion and minimize the health ministry’s exposure to malpractice lawsuits—these comments confirm that specialist physicians have their own reasons to question the accuracy and quality of cancer test results performed by pathology laboratories in the province.
Even as these events were unfolding earlier this month, the Canadian Association of Pathologists (CAP) called for new national guidelines to address issues of pathology test accuracy and quality. On December 17, at its annual meeting, it called for implementation of three guidelines at the national level. First, a national standard for cancer tests and the treatment protocols for a cancer patient after diagnosis. Second, establish a national benchmark for pathologist workload. Third, create a common checklist for pathology test reporting that would be implemented nationally.
What is notable in this public discussion about problems in the accuracy of pathology testing in Quebec is that physician leaders are willing to go on the record expressing their concerns about the variance in quality among different pathology laboratories in the province. Since physicians are a primary customer of pathology laboratories, this is a useful insight as to how their expectations for accuracy and quality from pathology testing is raising the bar for pathology laboratories in that province.
Related Information:
FMSQ REACTION: Retested Breast Cancer Pathology Results
Barrette stands firm: all cancer tests in Quebec have to be redone (June 2, 2009)
I am not able to make any sense of Dr. Gaetan Barette’s comments in the FMSQ response to the retesting of Quebec breast cancer samples by PhenoPath laboratories. He appears to have confused the diagnostic cut-off of 1% of cells showing nuclear positivity for a tumor to be declared ER positive, with the error rate as reported through retesting. Perhaps his remarks have been taken out of context. If not, and they do reflect confusion about fundamentally different aspects of biomarker testing, he lacks any significant understanding of the issues being discussed.