The immune systems of cancer patients may play a significant role in their treatment outcomes, according to a study on Tuesday.In the study, researchers at the University College London and the Francis Crick Institute found that cancer patients with a higher number of immune cells in their blood have a better survival rate.
They used a pioneering technique — Immune Lymphocyte Estimation from Nucleotide Sequencing (ImmuneLENS), which enables researchers to calculate the proportion of T cells and B cells (types of immune cells) from whole genome sequencing (WGS) data.
he team analysed over 90,000 WGS samples — both of healthy individuals and cancer patients. The findings described in the journal Nature Genetics showed that cancer patients had a lower proportion of T cells circulating in the blood compared to healthy individuals.
Further, T cell proportion was found to be a strong predictor of cancer outcomes, with higher proportions associated with 47 per cent fewer deaths over five years after surgery.
This effect was still significant when accounting for age, cancer stage, and across all cancer types — biological markers which can be added to current genetic diagnostic tests to help clinicians with more information on which to base treatment plans, said the researchers.
Professor Nicholas McGranahan, senior author of the study from UCL Cancer Institute, said while most immune system analysis until now has focused on the tumour itself, with the new tool, doctors “may be able to predict how long a cancer patient will survive better than the number of T cells in the tumour alone”.