A new sensitive test of DNA can predict how long the patients with ovarian cancer will survive, and initialize personalized treatment, according to new research, CBS News reports.

The technology, called QuanTILfy, counts the number of cells called tumor-infiltrating lymphocytes (TILs) in a cancer patient's tumor biopsy. Cancer patients with more of these cells in their tumor tend to have better outcomes.

This test is the first that can precisely count the number of immune cells present in a tumor sample.

Unlike currently available tests, which rely on staining tumor tissue and are subject to interpretation, the new test provides a sensitive, numerical readout.

"This is a big step forward to accurately count how many immune cells have infiltrated into the tumor," said Jason H. Bielas, a cancer geneticist at the Fred Hutchinson Cancer Research Center in Seattle, and lead researcher of the study.

 The researchers tested 30 tumors from ovarian cancer patients who had survived between one month and 10 years with their cancer.

They found the number of immune cells, as measured by the test, was threefold higher in patients who lived for more than five years after their cancer diagnosis, compared with those who lived less than two years with ovarian cancer. 

The QuanTILfy test provides a standardized way to count the immune cells in the tumor, using a digital approach. 

Particularly, Bielas said this test could be used to gauge whether a patient is likely to respond to a new class of cancer drugs, called immune therapy drugs, which are still in development but have so far been shown to be effective in some patients.