Missing the First Mammogram Increases Long-Term Breast Cancer Mortality Risk

A recent study conducted by researchers at Karolinska Institutet highlights the significant long-term implications of women not attending their initial mammogram screening. The investigation, based on extensive data from Sweden's mammography screening program and national health registries, involved nearly 433,000 women in Stockholm from 1991 to 2020, with follow-up extending up to 25 years.

The findings reveal that approximately 32% of women invited for their first mammogram chose not to participate. These women were less likely to engage in subsequent screenings, which often resulted in later-stage breast cancer diagnoses and poorer health outcomes. The study underscores that skipping the first screening is a strong predictor of delayed detection and increased mortality.

Women who initially missed their mammogram were more prone to advanced cancer stages upon diagnosis. The risk of developing severe stage III cancer was 1.5 times higher, and for stage IV, it was over three times higher than women who participated in their first screening. Over the 25-year period, nearly 1% of non-participants succumbed to breast cancer, compared to 0.7% among those who attended, indicating a 40% higher mortality risk.

Interestingly, the overall incidence of breast cancer was similar in both groups, around 7.7%, which suggests that higher mortality among non-participants results primarily from delayed detection rather than increased disease occurrence. Experts emphasize that while family history is an unchangeable risk factor, behavioral factors like attending initial screenings are modifiable. Increasing participation in first screenings could save many lives, as early identification provides an opportunity for timely intervention.

The study’s authors advocate for healthcare providers to implement targeted reminders and support strategies to encourage women to attend their first mammogram, thereby reducing the incidence of advanced cancer stages and mortality.

For more details, the full study is published in BMJ: DOI: 10.1136/bmj-2025-085029.