Australian researchers are looking at the immune cells that accumulate within tumours.

A new study has discovered that immune cells accumulating within the tumour environment, called tumour-resident T-cells, are a critical determinant in survival rates of patients suffering from throat cancer.

It suggests that strategies aiming to boost these T-cells at tumour sites could be beneficial to patients.

Oropharyngeal squamous cell carcinoma (OPSCC) is a form of throat cancer caused by environmental factors such as smoking or by human papillomavirus infection (HPV); the same virus that causes cervical cancer in women.

“We knew that patients with HPV-related OPSCC had far better clinical outcomes compared to other OPSCC patients but we didn’t know why,” says Ms Rehana Hewavisenti, lead author of the new study and researcher at the Centenary Institute and the University of Sydney.

In examining over sixty patient samples, Ms Hewavisenti and her colleagues discovered that increased levels of tumour-resident T-cells, whether in HPV or non-HPV OPSCC cases, was clearly associated with improved patient survival outcomes.

“It was the accumulation of these immune T-cells, in and around the tumour site that appeared to be key,” said Ms Hewavisenti.

The researchers also found in their study that HPV OPSCC patients generally had far higher levels of tumour-resident T-cells compared to their non-HPV OPSCC patient counterparts.

“We think these HPV positive patients tended to have better clinical outcomes as HPV infection is likely to favour the accumulation of these beneficial T-cells within the tumour area,” she said.

Dr Mainthan Palendira, senior author on the research paper, says that the research findings may have major implications.

“Now that we understand how important this immune response is in relation to OPSCC, we can begin developing new treatment strategies focused on recruiting these favourable tumour-resident T-cells directly to tumours,” he said.

Dr Palendira believes that looking at the amount of these T-cells in cancer could help clinicians to personalise the best treatment approach for individual patients.

“We also think that our research demonstrating viral (HPV) links with this tumour-resident T-cell accumulation could help in future cancer vaccine development efforts too,” he said.

The study is accessible here.