Study reveals increased risk of second cancers in breast cancer survivors

A new study looking at data from almost 600,000 patients in the UK has found that survivors of breast cancer are more likely to have secondary cancers such as endometrial or ovarian cancer in women and prostate cancer in men. The risk of developing cancer is significantly higher.

This study shows for the first time that this risk is higher for people living in areas with higher levels of socio-economic poverty.

Breast cancer is the most commonly diagnosed cancer in the UK. Approximately 56,000 people are diagnosed each year in the UK, the majority of whom are women (over 99%). Thanks to early diagnosis and improved treatment, her five-year survival rate has increased over time in the UK, reaching 87% by 2017.

people who survive breast cancer They are at risk of developing a second primary cancer, but until now the exact risk was unknown. Previously published research suggests that women and men who survive breast cancer have a 24% and 27% higher risk of second non-breast primary cancers, respectively, compared to the broader population. There is also some suggestion that the risk of second primary cancers varies by age. breast cancer diagnosis.

To provide more accurate estimates, a team led by researchers at the University of Cambridge used the National Cancer Registry dataset to examine more than 580,000 women diagnosed between 1995 and 2019. We analyzed data from more than 3,500 male breast cancer survivors. Their analysis results are Lancet Community Medicine – Europe.

Lead author Isaac Allen, from the University of Cambridge's School of Public Health and Primary Care, said: 'It is important to understand how much risk of developing a second cancer in another part of the body once you have one type of cancer. ” he said. Male breast cancer survivors, who are also at increased risk for a number of second cancers based on our data, can also learn from this to help their care team be on the lookout for signs of potential new cancers. Useful for conversations with. ”

Researchers found a significantly increased risk of cancer in the contralateral (i.e., unaffected) breast and endometrium. prostate cancer respectively for women and men. Women who have survived breast cancer have twice the risk of contralateral breast cancer, 87% risk of endometrial cancer, 58% risk of myeloid leukemia, and 58% lower risk of endometrial cancer than the general population. It was 25% more expensive. ovarian cancer.

Age at diagnosis was also important. Women diagnosed with breast cancer before age 50 are 86% more likely to develop a second primary cancer compared to the general population at the same age, whereas women diagnosed after age 50 are 86% more likely to develop a second primary cancer compared to the general population at the same age. was 17%. Increased risk. One possible explanation is that more young breast cancer survivors may have inherited genetic mutations that increase their risk of multiple cancers. For example, women with genetic changes in the BRCA1 and BRCA2 genes have an increased risk of contralateral breast, ovarian, and pancreatic cancer.

Women from the most disadvantaged socio-economic backgrounds had a 35% higher risk of second primary cancer compared to women from the most disadvantaged backgrounds. These differences were primarily driven by the risk of cancers other than breast cancer, particularly lung, kidney, head and neck, bladder, esophageal, and stomach cancers. This may be caused by smoking, obesity, etc. alcohol consumptionThese established risk factors for cancer are more common among more advantaged groups.

Allen Dr Clare Hall student said: 'This is further evidence of the health inequalities experienced by people from more disadvantaged backgrounds. “We need to fully understand why the risk of secondary cancers is higher,” he added.

Although male breast cancer survivors were 55 times more likely to develop contralateral breast cancer than the general male population, the researchers stressed that the individual risk remained very low. For example, for every 100 men diagnosed with breast cancer over the age of 50, about 3 developed contralateral breast cancer during her 25 years. Male breast cancer survivors were 58% more likely to develop prostate cancer than the general male population.

Lead author of the study, Professor Antonis Antoniou, from the School of Public Health and Primary Care at the University of Cambridge, said: “This is the largest study to date to examine the risk of developing second cancers in breast cancer survivors. They can do this and calculate more accurate estimates because of the excellent datasets available through the NHS.”

Katrina Brown, senior cancer intelligence manager at Cancer Research UK, said: “This study shows that people who have had breast cancer are at increased risk of developing a second primary cancer, and that this may vary depending on a person's socio-economic background. “However, further research is needed.” We need to understand what is causing this difference and how to address these health disparities. ”