Overweight or obese women may not detect cancerous breast lumps until they are much larger and more difficult to treat, a Swedish study has found.
Researchers from the Karolinksa Institute studied more than 2,000 women who developed breast cancer between 2001 and 2008, all of who had been receiving mammograms every 18 months to two years, as is standard in Sweden.
They found that women with higher body mass indexes (BMIs) were more likely to have a larger tumour when detected than women who were slimmer. Lead author of the study, Fredrik Strand, said this was either because the tumours were harder to detect because overweight women have larger breasts or because their tumours grew faster.
Women who are overweight are already at greater risk of developing breast cancer and, unfortunately, larger tumours carry a worse prognosis.
Therefore, these women may need more frequent mammograms to help spot tumours early, say the researchers. Women who are judged to be at greater risk of developing breast cancer – such as those with a family history – are already offered more frequent screening.
Speaking about the findings of the study, Strand said: “Our study suggests that when a clinician presents the pros and cons of breast cancer screening to the patient, having high BMI should be an important 'pro' argument”.