Counting tumor-attacking immune cells to predict ovarian cancer survival

Doctors have been able to predict how long patients with many different types of cancer can survive. They do this by counting the amount of tumor-attacking immune cells that migrate onto the tumor to try and get rid of the cancer. This is a sign of the body’s immune response to the cancer. It has been hard to measure these armies of immune cells until now.

Killer T-cell activation

Killer T-cell activation

Fred Hutchinson Cancer Research Center’s scientists have developed a new method for counting a unique class of cancer-fighting cells called “tumor-infiltrating T lymphocytes” or TILS. You can count these cells quickly, reliably, and cheaply in patients with early stage and advanced ovarian cancer.

This technology is a DNA-amplification technique that could be able to predict treatment response. It could also predict disease-free survival and cancer recurrence better than any of the current methods used. According to Jason H. Bielas, Ph.D., “Our experiments demonstrate an association between higher TIL counts and improved survival among women with ovarian cancer, and are consistent with prior observations that the immune response against ovarian cancer is a meaningful and independent prognostic factor.”

Researchers at Fred Hutch developed the digital assay to count TILs. They can also determine their frequency and create a grouping system to determine the population of the tumor’s T-cell population.

In a study, Robins, Bielas and colleagues tested the new technique on tumor samples from 30 ovarian cancer patients with survival outcomes ranging from one to twenty two months. They studied the levels of the TILs in each patient and compared those levels to the women’s survival. They discovered that the higher a patient’s TIL level, the higher the patients survival rate.