Serum progesterone concentration test can aid optimal timing of breast MRI in women with irregular periods

A simple blood test corresponding to the follicular phase (days 3-14) of a normal menstrual cycle can aid in optimal scheduling of breast MRI exams in premenopausal women with irregular cycles - possibly reducing the number of repeat scans and non-diagnostic tests patients experience and providing clearer images on which doctors make their recommendations, according to a study published in the December issue of the American Journal of Roentgenology.

Research has shown that performing breast MRI scans during the follicular phase of the menstrual cycle minimizes breast tissue enhancement. "In practice, many clinicians scan premenopausal women who lack normal menstrual cycles without regard to the timing of their hormonal cycle," said Richard L. Ellis, M.D., lead author of the study. "This can result in non-diagnostic exams and repeat scans," he said.

Using what is already known about the menstrual cycle and its effects upon normal breast tissue, Ellis, a radiologist at the Norma J. Vinger Center for Breast Care in Lacrosse, Wis., reasoned that a simple blood test could be used to optimize the timing of breast MRI exams. Blood tests were used to time exams in 11 women with irregular cycles. "None of the breast MRI scans performed in our small group of women resulted in high background enhancement of normal breast tissue requiring a repeat scan," said Ellis.

"Appropriate timing of a breast MRI examination for premenopausal women who do not have a normal menstrual cycle is a challenge. However, using existing science, we found that a simple blood test to determine a woman's serum progesterone concentration can aid in optimal timing of breast MRI. This is significant in an ever-increasing population of women requiring or eligible for breast MRI," said Ellis.