Chemotherapy is used to kill cancer cells and to curb tumours from growing in the patient’s body. However, a new study has suggested that chemotherapy may instead be helping spread the disease further leading to more aggressive forms of cancer.
While it has been known that the treatment shrinks tumours for short term beneficiaries, chemotherapy drugs increase the chance that cancer cells will migrate elsewhere in the body and may trigger a ‘repair’ system which allows them to grow back strong, a team of US researchers have discovered.
Professionals at the Albert Einstein College of Medicine in New York examined the impact of chemotherapy on breast cancer patients. They found that the number of blood vessel ‘doorways’ that allow cancer to spread throughout the body was increased in 20 patients who received two common chemotherapy drugs.
The study’s lead author Dr George Karagiannis told The Telegraph that the findings did not mean cancer patients should avoid chemotherapy, rather that they should be consistently monitored to check if the disease is spreading. The most advanced stage of breast cancer when it has spread beyond the breast to other organs in the body is called metastatic breast cancer and is the most fatal form of the disease.
Doctors could “obtain a small amount of tumour tissue after a few doses of preoperative chemotherapy” that would be analysed for signs of increased risk of this phenomenon – with women recommended to stop treatment before surgery if it is seen.
In experiments on mice, Dr Karagiannis and his colleagues found that the number of cancer cells circulating in the blood stream was increased when they received chemotherapy. “In this study we only investigated chemotherapy-induced cancer cell dissemination in breast cancer. We are currently working on other types of cancer to see if similar effects are elicited,” he told the newspaper. Chemotherapy can be taken as an oral tablet or through an intravenous drip.