Beating A Killer
Cancer was once the end of the line. Today, it can be managed and defeated
Starr's experience is repeated often by cancer survivors and the psychiatrists who treat them: The depression itself can often be worse than the disease, and once the depression is under control, life as a cancer survivor gains hope and meaning. A number of provocative research avenues are being explored in the area of depression and cancer. Often the listlessness, the lack of appetite, poor concentration, and sleeplessness can be part of a depressive illness, but they can also be symptoms of the cancer itself--what's called a "sickness syndrome." But could that syndrome respond to antidepressant medication? Can depression be considered a risk factor for cancer? Does the disease of cancer itself, like in pancreatic cancer, set off mechanisms that trigger depression? These are all questions still unanswered.
Clues. In trying to answer these questions, scientists have come up with some fascinating findings. One possibility has to do with body chemicals called cytokines, which are secreted by the immune system to fight off infection and disease, including cancer. Researchers at Emory University have found elevated levels of cytokines in medically ill patents with depression, and those levels correlate with symptoms of sickness behavior. Cytokines are ingenious in the ways they can cause depression or sickness behavior, insinuating themselves in a number of different brain pathways and wreaking biochemical havoc. It's not entirely clear, however, what comes first. In pancreatic cancer, for instance, one theory is that the cancer itself creates the cytokines. Nearly half of people with pancreatic cancer are depressed, and not just because they found out they have a disease with a poor prognosis. Indeed, the depression precedes the cancer diagnosis and is one of the symptoms of the illness.
A number of cancer treatments are based on cytokines. As Andrew Miller, director of psychiatric oncology at Winship Cancer Institute at Emory University, says, "What is clear is that there seems to be a connection between circulating levels of cytokines and behavior, but we don't know the directionality of that relationship."
Interferon is one of the usual treatments for melanoma, and it also triggers these cytokine storms. In one of Miller's studies, half of the 40 patients soon to be treated with interferon were given an antidepressant, and the other half were given a placebo. After three months on interferon, 45 percent of those on the placebo developed clinical depression, while only 11 percent of those on an antidepressant did. Does that mean a better long-term prognosis for those patients? No studies prove this, and doctors are emphatic about pointing out that succumbing to the disease cannot be seen as representing a failure of will on the part of the patient. "There have been headlines for many years that you needed to cope better if you wanted to live longer," says Dwight Evans, professor of psychiatry and neuroscience at the University of Pennsylvania School of Medicine. "As important as coping may be, I have had patients whose surviving family members actually felt responsible for their loved one's death, as if something had gone awry in family home relations. And in the end, you have two victims: one who succumbed to cancer and the other who tried to help but believed he failed."