Dense Breasts, Age Over 70 Raise Risk of Suspicious Lumps — UCH Study

Researchers at the University College Hospital (UCH), Ibadan, have found that women with heterogeneously dense breast tissue, those aged 70 and above, and grand multiparous women (those who have had five or more pregnancies) face markedly higher odds of suspicious breast lesions on advanced imaging.
The findings, presented at the I-Research and Innovation event organised by the College of Medicine, University of Ibadan, come from a retrospective analysis of women who underwent digital breast tomosynthesis (DBT), or 3D mammography, at the hospital.

According to Consultant Radiologist Dr Ayo Idowu, women with heterogeneously dense breasts had roughly 10 times the odds of a suspicious final assessment (BI-RADS 4A to 5) compared with those whose breast tissue showed other patterns. Women over 70 showed a similar tenfold increase in odds. Having had five or more pregnancies also emerged as an independent predictor.

The study compared sociodemographic, reproductive and radiological factors linked to suspicious findings against benign ones (BI-RADS 1–3). Heterogeneously dense tissue proved the strongest independent predictor. Menopausal status, family history of breast cancer and previous breast disease showed no significant association in this cohort.

DBT creates a three-dimensional view of the breast by taking multiple low-dose X-ray images from different angles. This reduces the problem of overlapping tissue that can hide abnormalities on conventional 2D mammograms, making it particularly useful for dense breasts.

“You need to undergo mammography before you know whether you have dense breasts. In our study, dense breasts were associated with about 10 times the odds of detecting a suspicious lesion,” Idowu said. She noted that DBT is available at UCH and can help evaluate women found to have dense tissue.

The radiologist stressed the importance of generating Nigerian-specific data. Risk factors identified in other populations do not always apply equally here. “We need our own data to look at our women and identify which clinical factors can predict suspicious findings during mammography,” she said.

Idowu advised Nigerian women to begin annual mammography screening from age 40 and to continue regularly. Early detection remains key to better treatment outcomes, even in the absence of symptoms.

ADVERTISEMENT

Breast density itself is both a risk factor for cancer and a factor that can mask lesions on standard imaging. Heterogeneously dense tissue, classified as BI-RADS C, is relatively common among Nigerian women in various studies from Ibadan and other centres. While overall breast cancer rates in African populations have historically been described as lower in some older reports, the masking effect of dense tissue and the need for local evidence remain important for screening strategies.

The UCH team’s work underscores the value of 3D mammography for women identified as having dense breasts and reinforces the call for routine screening tailored to Nigerian women’s risk profiles.