October 2005. Health officials in Newfoundland and Labrador reveal there had been serious errors in breast cancer tests conducted on women in St. John's — and that they were suspending them for breast cancer patients. Tests on more than 1,000 women over the previous eight years were suspect, and had been sent to a hospital in Toronto for retesting.

The hormone receptor test in question involves a process called immunohistochemical (IHC) staining. It determines whether a patient's breast cancer is being promoted or "fed" by hormones. If a patient is found to be ER/PR positive (estrogen receptor/progesterone receptor), anti-hormone drugs are prescribed. Such drugs block the production of hormones and abate the spread of cancer, increasing a patient's chances of survival significantly. About 75 per cent of breast cancers are hormone-related. All ER/PR tests for the province were conducted in St. John's, and pathologists are responsible for these tests.

Why is the test so important?

The results help determine the treatment that someone with breast cancer will receive. If the cancer is deemed ER/PR-positive, the patient is a candidate for the drug Tamoxifen, which has been shown to improve five-year survival rates.

Many risks are associated with this treatment, and they include blood clots, stroke and uterine cancer. That's why it's not prescribed to all breast cancer patients, only those whose cancers are deemed ER/PR-positive. Femara is another anti-hormone drug and often used in conjunction with chemotherapy and radiation.

Oncologists use test results from pathologists to help decide the best course of treatment. Pathologists have been called an oncologist's "best friend" for this reason. Many cancer patients don't realize a pathologist, often working in the background, has such a huge influence on their treatment.

What raised concerns?

Health officials suspended ER/PR tests in 2005 after a patient who initially tested "negative" was retested and found to be positive. A further retest of 25 hormone-negative patients found almost half "converted" to positive. In other words, half of those 25 patients were denied a shot of anti-hormone therapy in error. In the end, everyone who tested negative between May 1997 and August 2005 were retested at Mount Sinai Hospital in Toronto. That's 1,013 patients whose treatment plans were suddenly questioned.

What did the retests find?

Mount Sinai found St. John's got it wrong for about a third of these patients. So 275 living patients didn't get the treatment they should have. As a result of discovering the error, about half of this group were then prescribed anti-hormone treatment. On March 18, 2008, a day before the beginning of the inquiry, the province confirmed that 108 patients who died did not get adequate treatment. In other words, 383 patients of 1,013 didn't get the treatment they should have.

What did Eastern Health say about the retests?

In December 2006, after all retesting was completed by Mount Sinai, Eastern Health released some misleading numbers. They acknowledged about 1,000 people were retested. They admitted 117 patients would now be getting a change in treatment as a result. What they refused to release was:

• How many of those who were given the wrong treatment actually died.
• How many patients who got the wrong treatment couldn't be given Tamoxifen because it was too late for them.

It was only after a class-action lawsuit was launched that Eastern Health was forced to release these numbers in an affidavit. (Lawyers for the class action are watching this inquiry closely.) Eastern Health also revealed not all patients were informed when a problem was first detected.

Eastern Health says it didn't want to release all the numbers regarding the errors because it feared they would cause alarm. In resigning, the CEO acknowledged this was a mistake. In court documents, Eastern Health argues ER/PR testing is an imprecise science that is still evolving. They also blame technical problems with the equipment. Pathologists suggest subjecting ER/PR samples to retesting at any lab in Canada would similarly turn out a high rate of error.

In reality, external audits of the lab released publicly in February 2008 identified staff incompetence, poor quality control, deficient procedures and a general negligence in keeping up with the evolution of this subspecialty of pathology. There was nothing wrong with the equipment. The lab was simply working at well below most standards. The audits found a "revolving-door" of pathologists and a general poor understanding of immunohistochemical testing. It was noted there weren't any pathology reference books in the lab or even an internet connection. Eastern Health fought in vain to keep these reports out of the inquiry, arguing they were peer reviewed and thus privileged. A judge disagreed. Subsequent audits have found the problems have been corrected. The lab has been overhauled.

What are the implications for the rest of Canada?

Although the audits revealed the St. John's lab was working at well below most standards, the fact is there are no national standards for hormone receptor testing. The Canadian Association of Pathologists says it's working on them. Britain does have standards in place. The U.S. is working on national standards in association with Cancer Care Ontario. The situation in St. John's also demonstrates the hazards of a pathologist shortage. Hormone receptor testing is really a subspecialty of pathology. It should also be noted that 50 women in Newfoundland and Labrador were mistakenly told they had advanced stages of breast cancer when they didn't. Some had mastectomies. The inquiry won't be addressing this problem specifically.

What is the job of the inquiry?

Even though Eastern Health announced it suspended testing in 2005, the government only called the inquiry in 2007 when it became clear how high the error rate was. The commission of inquiry on hormone receptor testing is headed by Madame Justice Margaret Cameron. Her mandate is not to assign blame, but rather determine "what caused or contributed to the problems, when the problems came to light and whether they could have been detected earlier." The inquiry will also look "into whether, once detected, the responsible authorities communicated in an appropriate and timely manner with the general public."

[an error occurred while processing this directive]