Genetic testing could help identify breast cancer patients at high risk for the formation of blood clots in their veins, new research suggests.
This problem, called venous thromboembolism (VTE), is a serious and potentially fatal complication that can occur during cancer treatment, particularly chemotherapy.
Because breast cancer is one of the most common cancers, breast cancer patients account for a large number of cancer-related VTE cases, said study author Judith Brand. She’s a postdoctoral researcher in the department of medical epidemiology and biostatistics at Karolinska Institute in Stockholm, Sweden.
Venous thromboembolism is preventable through treatment with an anti-clotting drug. But side effects, such as bleeding, mean this therapy is not routinely used in patients undergoing chemotherapy, the researchers explained.
The new study included more than 4,200 women in Sweden diagnosed with breast cancer between 2001 and 2008, and followed until 2012. The one-year rate of venous thromboembolism was 9.5 percent among those who received chemotherapy and had a high genetic risk, compared with 1.3 percent among those who did not receive chemotherapy and had low genetic risk.
Older chemo patients with high genetic susceptibility had the highest risk of venous thromboembolism. In patients 60 and older who had chemotherapy and a high genetic risk, the one-year rate was 25 percent, the findings showed.
The study was published Nov. 1 in the journal Clinical Cancer Research.
Breast cancer patients receiving chemotherapy are not routinely being examined for VTE prevention in today’s clinical practice, Brand said in a journal news release. Our study demonstrates that information on genetic susceptibility can be used to identify patients at high risk of developing VTE.
The findings may help guide future studies evaluating risk of venous thromboembolism in chemotherapy outpatients and preventive treatments, Brand suggested.
Because older patients demonstrated a stronger genetic effect and higher VTE incidence, this group requires special attention in future risk-stratification efforts, she concluded.