Growth Hormone therapy and Breast Cancer

Many years ago, several studies have pinpointed the fact that postmenopausal women on hormone replacement therapy (HRT) have a higher risk of breast cancer.

A recent study at the Fred Hutchinson Cancer Research Center confirms this hypothesis after an extensive study involving a large group of 705 postmenopausal women that had been diagnosed with primary invasive breast cancer. This group of women was studied alongside with another 692 age-matched controls.

The results revealed that women, who were long-term users of HRT, whether they were on 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. The results also indicated that women who were on HRT for 57 months or more had a three-fold increased risk whilst those who were currently on combination therapy (estrogen plus progestin) had a four-fold increase in the risk of lobular breast cancer.

During the study, it was also noted that women who had gone for two or more screening mammograms before they discovered they had cancer had twice the incidence of breast cancer than women who had never had a mammogram. Having just one screening mammogram increases breast cancer risk by almost 60 percent. The effects of screening are thus seen to be harmful.

It was also noted that women who has first- degree relatives with breast cancer has an increased risk of 71 percent of contracting cancer.

Source: Chen, Chi-Ling, et al. Hormone replacement therapy in relation to breast cancer. Journal of the American Medical Association, Vol. 287, February 13, 2002, pp. 734-41.