Scientists have found that, while shrinking tumors, chemotherapy opens a gateway for breast cancer cells to spread into the blood and other parts of the body.
In 2012, a groundbreaking study was published which explained how chemotherapy can backfire and boost cancer growth.
In 2016, we learned that chemo causes long-term immune system damage in breast cancer patients, reducing key immune cells for at least 9 months after treatment.
This year we have another study, published in the journal Science Translational Medicine, which offers more insight into how chemotherapy could cause cancer to spread, and trigger more aggressive new tumors.
In the latest study, researchers studied the impact of chemo drugs on breast cancer patients and found that the drugs increased the chance of cancer spreading to other parts of the body. Once breast cancer spreads, it becomes almost impossible to cure with conventional treatments.
Many breast cancer patients are given chemotherapy before surgery, even though half of them don’t need it, and this new research offers further insight as to how chemo can trigger the spread of cancer cells around the body, while it is striking a primary tumor.
As I’ve said many times, chemotherapy is often only a short-term solution to a long-term problem.
The new study presents evidence that chemotherapy can switch on a repair mechanism in the body which ultimately allows tumors to grow back stronger. It also increases the number of ‘doorways’ on blood vessels which allow cancer to spread throughout the body.
Dr George Karagiannis, of the Albert Einstein College of Medicine in New York, found the number of doorways was increased in 20 patients receiving two common chemotherapy drugs (patients were given neoadjuvant paclitaxel after doxorubicin plus cyclophosphamide).
He also discovered that chemotherapy increased the number of cancer cells circulating the body and in the lungs of mice given breast cancer.
Dr Karagiannis and colleagues suggest women be monitored during chemotherapy to check if cancer is starting to circulate and if doorways were emerging. If this is found to be the case, they recommend discontinuing chemo before surgery.