Cancer patients and doctors struggle to predict survival

When a doctor tells a patient that she has cancer and has just a year left to live, that patient often hears very little afterward. It's as though the physician said "cancer" and then "blah, blah, blah."

Anxiety makes it difficult to remember details – and the worse the prognosis, the less the patient tends to remember. Recent studies have found that cancer patients retain less than half of what their doctors tell them.

So it's not surprising, perhaps, that a patient with advanced cancer can leave her oncology appointment thinking she has a set amount of time left to live. "The doctor gave me a year," she'll say, as though she were a half-gallon of milk with a "sell-by" date printed on her head.

But prognoses are almost never that clear-cut, despite the fact that patients need to make big decisions based on those numbers. Should she quit her job? Take that dream cruise? Write a living will?

Physicians play a part in the confusion, too. Doctors consistently overestimate how long a patient has to live, according several studies. In one study of terminally ill patients, just 20 percent of physician predictions were accurate. The majority, 63 percent, were overoptimistic. And if patients think a doctor is doing a good job of communicating with them, they're more likely to be erroneously optimistic about a cure. That can keep patients from fulfilling key goals before they die. One big challenge is that a prognosis is not an absolute number. Doctors often look up data gathered by the National Cancer Institute or the American Cancer Society, or they will use their own clinical expertise.

The data are typically given as a median, which is different from an average. A median is the middle of a range. So if a patient is told she has a year median survival, it means that half of similar patients will be alive at the end of a year and half will have died. It's possible that the person's cancer will advance quickly and she will live less than the median. Or, if she is in good health and has access to the latest in treatments, she might outlive the median, sometimes by many years.

Doctors think of the number as a median, but patients usually understand it as an absolute number, according to Dr. Tomer Levin, a psychiatrist who works with cancer patients and doctors at Memorial Sloan Kettering Cancer Center in New York. He thinks there is a breakdown in communication between the doctor and patient when it comes to the prognostic discussion.

Levin and other people who work on the social and emotional side of cancer – psychiatrists, psychologists, behavioral scientists – are training people who treat cancer on how to make the conversation easier for everyone.

During a two-day session at Memorial Sloan Kettering on communicating with cancer patients, three doctors were brought to a small room, where they practiced giving a prognosis to an actor. The doctors were encouraged to set an agenda for the discussion, ask the patient what he or she wanted from the session, and to present the prognosis as a best-case, worst-case and most likely scenario. They were encouraged to tell patients to prepare for all three scenarios, and to write down the prognosis so the patient would remember the specifics. The best-case scenario helps to preserve hope, and that hope is not simply a warm feeling — 1 in 10 patients do much better than the median survival time for their cancer.

But many people avoid preparing for the worst-case scenario, Levin says, "because the worst-case scenario is the scariest." Sometimes a family's desire to "think positive" can make people reluctant to bring up death or dying. "And the end result is that the patient is left alone with his fear of dying and he can't speak to anyone about it." Levin also wants the doctors to make it clear to their patients that they will not abandon them if the worst-case scenario comes to pass.

During the role-playing session, Dr. Asma Latif sat across from an actress portraying a 42-year-old woman with stage III ovarian cancer.

"The goal of the treatment is to cure the cancer," she said to the pretend patient. "But we know that this often is not possible. And actually the most likely scenario is that we don't cure the cancer. And I" — Latif paused. She could see that the patient was becoming visibly distressed by the uncertainty of her prognosis. "Can I do a time out? I don't know how to recover from this."

Latif was struggling with giving a prognosis that had a wide and vague range of outcomes. Levin assured her that while it seemed cumbersome, it was more honest and would help patients make difficult life decisions.

Ultimately, Latif agreed that she would try this with her patients, that she could see the value in it. But after the role-playing was done, all three doctors agreed that this session was more difficult than others they had undertaken, even more than discussing death and dying.

Our series is produced with member station WNYC, and with WETA, whose documentary Cancer: The Emperor of All Maladies will air on PBS in March. Copyright 2019 WNYC Radio. To see more, visit WNYC Radio.