John Shepherd

Research Interests

Development of quantitative imaging methods and applications in breast cancer and osteoporosis using x-ray and bioimpedance techniques

Research Summary

Breast density, is perhaps the strongest and least recognized risk factor for breast cancer. It is a marker for biological conditions that predispose cancer and for hormonal stimulation of the breast: increased endogenous estrogen is associated with increased breast density-and a substantially increased breast cancer risk. Breast density provides a better estimate of breast cancer risk than do standard "risk factors," especially in postmenopausal women. However, current measurement methods are neither precise nor accurate enough to be used in individual women to classify their risk status nor to follow changes in risk based on a pharmaceutical intervention. Thus, there is a need for new technologies to make measurements inexpensively available for clinicians and to allow patients to better assess their treatment options.
Our central hypothesis is that absolute breast compositional density, measured using novel techniques developed for bone densitometry, can be used as an accurate and precise method for estimating the risk of breast cancer as a means to clinically assess risk. These novel densitometric techniques have never been applied to mammography and offer the possibility of making breast density universally available to women who receive routine mammography.

Publications:

Selected Publications