SEATTLE, WASHINGTON. Several studies have found an increased risk of breast cancer among postmenopausal women on hormone replacement therapy (HRT). Researchers at the Fred Hutchinson Cancer Research Center now confirm this connection. Their study involved 705 postmenopausal women who had been diagnosed with primary invasive breast cancer and 692 age-matched controls. Recent long- term users of HRT, whether estrogen alone or estrogen plus progestin, were found to have a 60-80 per cent increased risk of breast cancer. The risk increase was particularly high for lobular breast cancer. Women who had been on HRT for 57 months or more had a three-fold increased risk for this type of cancer while women who were currently on combination therapy (estrogen plus progestin) had a four-fold increase in the risk of lobular breast cancer.
The researchers also noted that women who had had two or more screening mammograms were twice as likely to
have been diagnosed with breast cancer as were women who had never had a mammogram.
Even having just one screening mammogram increased the chance of a diagnosis of breast cancer by almost 60 per cent.