New research has shown that women over 50 who have been treated for ductal carcinoma in situ ( DCIS ) are more likely to be alive ten years later than women in the general population.
DCIS differs from breast cancer because it is non-invasive, meaning it cannot spread around the body. However, because it can progress into an invasive breast cancer, which can be life-threatening, it is usually treated with surgery, or surgery and radiation therapy. The number of women being diagnosed with DCIS is increasing because it is picked up by breast screening programmes.
The findings have shown that, although women with DCIS have a higher risk of dying from breast cancer, overall they have a slightly lower risk of dying from any cause.
According to researchers from the Netherlands Cancer Institute, these results should provide reassurance to women who are diagnosed with the disease.
Researchers have studied data on almost 10,000 Dutch women who were diagnosed with DCIS between 1989 and 2004. They tracked the patients over an average of 10 years and compared their death rates with the expected mortality in the general population.
They found that women over 50 who had been treated for the condition had 10% lower risk of dying from any cause compared to the general population.
The study has shown that DCIS patients had a two and half per cent risk of dying of breast cancer after ten years. At 15 years, the risk was four per cent.
These rates are higher than in the general population. However, the study also showed that the rates were getting lower in women diagnosed with DCIS more recently.
Patients were 10% less likely to die from all causes combined compared to the general population. Specifically, they had a lower risk of dying from diseases of the circulatory, respiratory and digestive systems and other cancers.
This finding is important because treating DCIS with radiotherapy could cause side-effects, including damage to nearby organs such as the heart.
However, in one fifth of the patients who die, the cause is breast cancer, which is likely to result from progression of the DCIS.
The researchers are waiting for the results of further research to identify the factors that contribute to the risk for recurrence and progression from DCIS for each individual patient. ( Xagena )
Source: European Cancer Congress, 2017