New scrutiny of breast cancer misdiagnoses
Diagnosing the earliest stage of breast cancer can be surprisingly difficult, prone to both outright error and caseby-case disagreement about whether a cluster of cells is benign or malignant, according to a New York Times examination of breast cancer cases.
Advances in mammography and other imaging technology during the past 30 years have meant that pathologists must render opinions on eversmaller breast lesions, some the size of a few grains of salt. Discerning the difference between some benign lesions and early-stage breast cancer is a particularly challenging area of pathology, according to medical records and interviews with doctors and patients.
Diagnosing what is known as ductal carcinoma in situ “is a 30-year history of confusion, differences of opinion and under-and overtreatment,” said Dr. Shahla Masood, the head of pathology at the University of Florida College of Medicine in Jacksonville. “There are studies that show that diagnosing these borderline breast lesions occasionally comes down to the flip of a coin.”
There is an increasing recognition of the problems, and the federal government is now financing a nationwide study of variations in breast pathology, based on concerns that 17 percent of the ductal carcinoma cases identified by a commonly used needle biopsy may be misdiagnosed. Despite this, there are no mandated diagnostic standards or requirements that pathologists performing the work have any specialized expertise, meaning that the chances of getting an accurate diagnosis vary from hospital to hospital.
Ductal carcinoma in situ is diagnosed in more than 50,000 women a year in this country alone. The abnormal cells, which are encased in breast ducts, are removed before they develop into invasive cancer.
There are estimates that if left untreated, the condition will turn into invasive cancer 30 percent of the time, though it could take decades in some cases.