Immune system may help ovarian cancer survival

Findings from a new study shows that the immune system T cells may play a crucial role in the survival of women with ovarian cancer.

According to investigators the findings support ongoing research efforts to fight cancer through boosting the body’s built-in defenses. They also speculate that looking for T cells within ovarian tumours could help doctors predict a woman’s prognosis and guide her treatment. Their study found that women in the advanced stages of ovarian cancer, with T cells contained in their tumour, lived nearly three times longer than women without these cells. Among women who had a complete response to surgery and chemotherapy, those with tumours containing T cell remained progression-free 10 times longer. T cells assist with the coordination of the body’s overall immune response. They can directly attack foreign, infected or cancerous cells. Investigators believe that when T cells are able to infiltrate tumours, a strong immune response “kicks in” during treatment and lasts into the long-term, study author Dr. George Coukos explained. He added, the hope is to use an immune-boosting treatment approach such as a cancer “vaccine” to enhance patients’ natural T cell response, or to “generate a response from scratch” in patients who lack a spontaneous one. The study used frozen tumour samples taken from 186 women before treatment for advanced ovarian cancer, a disease with a typically dim prognosis. In this study, 38% of women whose tumours contained T cells survived for five years, compared with just 4.5% of those whose tumours lacked T cells. In the past researchers had found that some ovarian tumours contain T cells, but the meaning of this has been unclear. According to Coukos the new study ties the presence of these cells, independently, to ovarian cancer survival. Researchers have already found the same association with several other cancers, including the skin cancer melanoma, and cancers of the breast, prostate and colon. Based on these findings and past research, the study authors estimate that about half of women with advanced ovarian cancer have T cells in their tumours. Finding out why only half of them do is an important question, Coukos said. In addition, he and his colleagues point out, the presence of T cells in ovarian tumours could potentially be used to predict a woman’s prognosis. (SOURCE: Reuters Health &The New England Journal of Medicine)