Results of retesting 2,856 women were made public last week, putting pathology in the media spotlight

In Quebec, concerns continue about the accuracy of breast cancer testing performed in the province. Last Wednesday, Quebec’s Health Minister, Yves Bolduc released the results from a project that retested breast cancer tissue from 2,856 women. This review involved cases where the original pathology analysis for estrogen receptor (ER) or HER-2 marker status by immunohistochemistry (IHC) had occurred between April 1, 2008, and June 1, 2009.

Yves Bolduc, Quebec’s Minister of Health, discusses problems with inaccurate pathology lab tests for breast cancer. (Photo copyright The Canadian Press)

Yves Bolduc, Quebec’s Minister of Health, discusses problems with inaccurate pathology lab tests for breast cancer. (Photo copyright The Canadian Press)

Bolduc reassured the public that Quebec’s results “are better than most in the world.” The review testing of the 2,856 cases determined that 87 women had received a false negative result from pathology laboratories in Quebec that had done the original pathology testing. Among these women, 39 needed to alter their treatment and five of these women have died. Bolduc has stated that it is impossible to ascertain whether improper treatment due to an inaccurate pathology test is the reason these women died.

The review and retesting of the 2,856 cases was done by PhenoPath Laboratories, of Seattle, Washington at a cost of $800,000. PhenoPath’s founder and Medical Director is Allan M. Gown, M.D., a recognized expert in the field of immunohistochemistry.

It was back in May when pathologist pathologist Louis Gaboury, M.D., at the Université de Montréal, delivered a report to the Quebec Ministry of Health. Based on a study of 25 pathology laboratories in Quebec, it indicated a high rate of inaccuracy in breast cancer testing performed by pathology laboratories in the province. “If we think that there’s about 10% to 30% variation [in accuracy between pathology laboratories], then it’s a significant number of people out there with a wrong diagnosis,” stated Gaboury at the time. He is President of the Association des Pathologistes du Québec. (See Dark Daily, June 1, 2009: “ Study Indicates Errors in Breast Cancer Testing in Canadian Province of Quebec.”)

Regular readers of Dark Daily know that Canada has uncovered a number of pathology laboratory testing failures. The biggest case became public in October 2005, in the Provinces of Newfoundland and Labrador. Based on an outside review of 1,013 breast cancer patients who had tested negative between May 1997 and August 2005, it was determined that, because of inaccurate pathology tests on estrogen receptors, 383 women in the retest group had not gotten appropriate treatment. Of this number, 108 patients had died by the time the pathology test review was conducted. (See The Dark Report, May 18, 2009: ER/PR Testing in Canada Continues to Make News.)

But what got less press and public attention about the Newfoundland/Labrador pathology testing failures was the rate of false positives. Press reports indicated that around 50 women in these two provinces whose tissue was originally tested during 1997-2005 were wrongly told that their breast cancer had reached an advanced stage. These women then received unnecessary treatment, including, in some instances, mastectomies.

In Quebec, the issue of false positives from inaccurate breast cancer testing has not been discussed publicly. Rather, the response to the findings of the breast cancer case review from the physician community has been to criticize other aspects of how the government handled this matter. The Quebec Association of Medical Specialists (FMSQ) conducted a press conference to inform the public that it questions the standards used in the outside review of the 2,856 breast cancer cases.

This aspect of the unfolding events in Quebec that should be an early warning to the pathology profession: going forward, there will be more professional and public scrutiny of the accuracy and reliability of cancer test results produced by pathology laboratories.

Heightened and very public scrutiny of the accuracy of cancer testing will not be limited to pathology laboratories in Canada. To date, Canada is simply an early example of what happens when the public learns that accuracy and quality issues in individual pathology laboratories can contribute to an unacceptably high rate of inaccurate test results. In Part Two of Dark Daily’s coverage about problems with breast cancer testing in Quebec, this aspect of the unfolding story will be addressed in more detail.

Related Information:

39 Quebecers with breast cancer wrongly treated: Quebec releases results of pathology retests ordered after disparities revealed

Standards for breast cancer tests queried: Debate erupts over whether results of hormone receptor tests are positive or negative

Quebec will likely re-do breast cancer tests (June 2009)

1 in 5 breast cancer hormone tests wrong, Quebec pathologists fear (May 27, 2009)

FMSQ REACTION–Retested Breast Cancer Pathology Results

Specialists want higher breast-cancer standards

Regarding Newfoundland Pathology Testing: Hormone testing–Judicial inquiry probes faulty breast cancer tests

THE DARK REPORT – ER/PR Testing in Canada Continues to Make News