Menopausal Status Should Guide Mammography Intervals

A new study suggests that menopause may be a more important indicator than age when determining breast cancer (BC) screening intervals.

Researchers at the University of California Davis (UCD; USA), the University of California, San Francisco (UCSF; USA), and other institutions conducted a prospective cohort study of 15,440 women (40–85 years of age) to compare the proportion of BC with less versus more favorable prognostic characteristics in women screening annually versus biennially by age, menopausal status, and postmenopausal hormone therapy (HT) use. The researchers defined less favorable prognostic characteristics as tumors that were stage IIB or higher, size greater than 15 mm, positive nodes, and any one or more of these characteristics.

The results showed that among 2,027 premenopausal women (13.1%), biennial screeners had a higher proportion of tumors with less favorable prognostic characteristic, compared to annual screeners. Among women taking postmenopausal HT, biennial screeners also tended to have tumors with less favorable prognostic characteristics than annual screeners, but differences were not statistically significant. Postmenopausal women not using HT had a higher proportion of invasive cancers if they were screened biennially than women who were screened annually. The study was published on October 20, 2015, in JAMA Oncology.

“Our findings suggest that menopausal status may be more important than age when considering breast cancer screening intervals,” concluded lead author Diana Miglioretti, PhD, and colleagues. “If screening guidelines were based on menopausal status rather than age, some women ages 40 to 54 years might be recommended for more frequent screening and others, less frequent screening.”

The frequency at which women should receive screening mammography remains controversial in the United States. In 2009, the US Preventive Services Task Force (USPSTF; Rockville, MD, USA) updated breast cancer screening guidelines to recommend routine biennial mammography for women ages 50–74 years, based on evidence suggesting that the harms of more frequent screening outweigh the small estimated added benefit of annual screening. In contrast, the American Cancer Society (ACS) recommends annual screening for women 40 years of age and older.

Related Links:
University of California Davis
University of California, San Francisco
US Preventive Services Task Force