Especially when they give the patient or their family the news that they may not live to the next week.
A mixture of experience (“the last time I had a patient with those blood results and that diagnosis who looked that sick they died a week later”) and guess work.
In general, dying people look, to the trained observer, like they are dying. We’re not always right, but when someone has cancer and one or more organ systems failing, an imminent death is very likely.
It isn’t like TV where the dying patient looks just like the well patient but with less blusher and lipstick- dying people look like they are dying “a bit pale” isn’t the half of it.
I’d be more curious how doctors could predict that someone has “six months to live” or “12 weeks to live.” You hear so many stories of people who have beaten those predictions. It might not be such a stretch to see that someone might not make it but a few days, if it’s clear that they are being overtaken by their illness, but to aver that someone has six months seems arbitrary. How often are they right on the money?
My dad is an oncologist and he once said that it doesn’t really work that way–not down to the week. It’s more like you say “X number of people have had this outcome”–you’re not giving them a definite, “You have six months.”
It’s not that hard to find out information like “50 percent of patients with [type of cancer] live for five years after diagnosis” or “median survival after diagnosis is [x number of weeks or months].” By the time a doctor is having that conversation, they probably have a solid idea of how advanced the cancer is, how well the patient’s body is or is not holding up, and how fast the cancer is growing or spreading or how fast organs (for example) are failing. So there’s plenty of information to go on. And I agree that diagnoses on TV or in movies are probably a lot more specific than real ones.
In that case the patient’s health would obviously be pretty terrible. You’re not really going out on a limb if you say someone who (for example) is comatose with multiple tumors and organ failure is probably going to die in a couple of days. By the way, I hope this isn’t brought on by anything you’re dealing with in real life.
My father had a tumor in his colon (at age 64, one year prior to his next scheduled colonoscopy). It was removed surgically, but his doctor told him that without chemotherapy he would have six months to live. My guess was that the doctor was giving him a ballpark estimate of the best-case scenario. He went through chemo for a while, but the cancer persisted and eventually he decided he had had enough and stopped treatment. He made it 11 more days.
It is clearly not an exact science, but in this case I think the doctor did his best to give an outside estimate. I’d rather have that than “you’ll be fine for another 5 years at least” and keel over dead in a month!
There’s a “statistical way” as mentioned already, but there are also some developments that indicate there’s going to be a pretty much inexorable, and rapid, course towards death.
For example, if the cancer has spread to the liver, and if it has so infiltrated that organ to the point that its function is impaired, death is almost always going to occur in days to weeks. Admittedly, this a prediction based on having observed other people in the same circumstance. (Just to be clear, I should note that if the liver function is impaired strictly because of a blockage of the outflow tract of the liver (i.e. biliary obstruction), once that blockage is removed, the prognosis can be excellent, and cure may even be possible.)
Another example: if a person is not drinking and has declined an IV, death will almost always occur in no more than two weeks.
There are also some developments that tell the doc it’s ‘time to call the family in’ (if they’re not already there) or to suggest the family stick around if they were thinking of leaving. In this respect, the person’s breathing pattern can sometimes indicate that death is highly likely to occur in hours. Another harbinger of a patient’s imminent demise is when their circulation is starting to ‘shut down’ (as evidenced by things like their extremities getting cold, but not just their hands).
But all of the above are just specific instances of ‘experience’ or ‘statistics’ at work. And that’s the bottom line about how “doctors predict the timing of cancer deaths”. So, really just rephrasing what others have already said: if study after study shows that for people with a particular type of cancer, and a particular pattern of spread, 99% are dead within one year, it’s pretty much certain that the next patient with that cancer and pattern won’t survive a year. Now, to get a sense of whether that person is more likely to die in one month or ten months, other things are taken into consideration (like those mentioned above, for example). Another major modifier of the overall survival statistic is the person’s ‘functional status’. Someone suffering from a particular type of cancer who is bed-bound because of weakness, will almost certainly die a lot sooner than someone with the same cancer and same pattern of spread who is still going to the mall, etc. This doesn’t imply, of course, that encouraging or forcing a patient with advanced cancer to be active will delay death. Being bed-bound is simply a reflection of the overall high impact of the cancer in that person by that time. Making them go for a walk in the park isn’t going to change that.
No, but it’s something that one of my friends are going through w/ a family member, unfortunately.