Immunotherapy could 'substantially' reduce return of aggressive form of breast cancer

Treating triple negative breast cancer with immunotherapy alongside chemotherapy could “substantially” reduce the number of recurrences of the cancer, research has suggested. Triple negative breast cancer is an aggressive form of breast cancer that is diagnosed when the cancerous tumor tests negative for three receptors: the hormones oestrogen and progesterone, and the HER2 protein.

The uncommon cancer is typically treated by surgery and chemotherapy, Cancer Research UK says. However, research presented at the ESMO 2019 Congress - currently taking place in Barcelona, Spain - claims that also treating the condition with immunotherapy could prove significantly beneficial. Immunotherapy is a form of cancer treatment that helps the body’s immune system learn to recognize and attack cancer cells.

A trial investigating the benefits of treating triple negative breast cancer patients with immunotherapy and chemotherapy was conducted across 124 sites in 21 countries between March 2017 and September 2018. All individuals taking part in the study, of which there were 1,174, underwent surgery and cycles of chemotherapy to shrink their cancerous tumors. Of these, 784 participants received the immunotherapy drug pembrolizumab before and after undergoing surgery. Meanwhile, 390 of the participants were given a placebo before and after surgery. According to the study’s findings, 64.8 per cent of those who took the immunotherapy drug later showed no signs of cancer in their tissue, 13.6 per cent more than those who took the placebo.

“Triple negative breast cancer is a particularly aggressive form of cancer with the potential to devastate lives,” said lead author Professor Peter Schmid from Queen Mary University of London and St Bartholomew’s Hospital.

“We have been desperately looking for better treatment options. These early results suggest that the addition of immunotherapy to chemotherapy leads to a substantial reduction in recurrences in this form of breast cancer.” Professor Schmid added that while these are “preliminary results”, they are “very promising”. “If we prevent the cancer from coming back, we cure more patients, but we need longer-term data to confirm this,” he said.

The professor explained to news agency PA that when the cancer is “completely gone out of the breast”, patients have an increased likelihood of longterm survival and “cure rates are much higher”. “Whereas in patients where there is still cancer visible at the time that we do the operation, they have a higher risk of recurrence,” he said.