A class action lawsuit claims several female cancer patients were treated for their disease without actually having cancer. The complaint also claims the health authority failed to control the quality of breast cancer tissue specimens for estrogen and progesterone hormone receptivity. The alleged misdiagnoses resulted in needless surgeries and chemotherapy treatments, as well as unnecessary mental distress.
Some patients diagnosed with breast cancer since 1997 were not responding as expected to treatment. In 2005, cancer tissue samples collected from approximately 1,000 patients were sent to the Mount Sinai Laboratory in Toronto for retesting. The Mount Sinai retesting showed an error rate of up to 20% when testing for estrogen and progesterone receptors.