What goes into figuring out lung cancer prognosis, and how accurate is it? What’s the link between longevity and quality of life? Here to share expertise and insight into lung cancer prognosis is Heather Wakelee, MD, who specailizes in the treatment of lung cancer, thymoma, and mesothelioma. She serves as Deputy Director of the Stanford Cancer Institute, and Division Chief of Medical Oncology at Stanford Medicine, where she's the Winston Chen and Phyllis Huang Professor.
I’ve been a practicing medical oncologist focused on thoracic oncology for more than 20 years. When it comes to prognosis, the first thing I tell patients is that no one can give them a specific number. If someone does, you can’t take it as truth, because nobody has a really clear way of knowing the future.
When I teach trainees in my role as professor of medicine and division chief of medical oncology at Stanford Medicine, I emphasize how careful you need to be when having a conversation about prognosis. You can have a long, thoughtful conversation with someone about all the different factors at hand, but the moment a number comes up, that’s often the only thing they remember.
There’s so much uncertainty at the time of diagnosis that it’s natural to grab onto anything that feels concrete. The problem is that those numbers don’t actually reflect what’s going to happen to you as an individual.
Instead of focusing on a number, I talk about a range. I try to ground that range honestly. There are people whose disease advances very quickly, sometimes going from diagnosis to death in a matter of days. That’s not common, but it does happen, especially when someone comes in very sick, and cancer has already affected their major organs.
At the same time, many people live for years — sometimes more than a decade — with metastatic lung cancer. Both ends of that spectrum are real. The challenge is that, at the beginning, you don’t know where someone is going to fall within that range.
Our goal is to understand and help you understand the range of possibilities, and then narrow that range based on what we know about you and your cancer.
Factors That Help Shape Your Prognosis
When I’m considering a lung cancer prognosis, I consider factors in two broad categories: the person and the tumor.
Person-focused factors include things such as how healthy you were before the cancer. I also look at how much the cancer is already affecting you — how symptomatic you are and how much it’s affecting your daily life. Those are all important pieces of information.
Age comes up as part of the fuller picture, but the concern is less about your age and more about your fitness. A healthy older adult may do much better than someone younger who has other medical issues or is already struggling physically.
Then there are the tumor-specific factors:
- How advanced is the cancer?
- How many parts of your body are involved?
- Is it affecting how your organs are functioning?
We use imaging to understand that. Sometimes, I show my patients the scans if they want to see them, as it can help explain what I’m concerned about. But not everyone wants to see that, so I always ask first.
We also look closely at the biology of the tumor. In lung cancer, this includes whether the tumor is likely to respond to immunotherapy or targeted therapy, or whether it may be resistant to these treatments based on specific mutations. Those details help us estimate the chances that a treatment will work. What they don’t tell us very well is how long that treatment will work, which is a big unknown.
Using Data Wisely
There’s a mix of clinical data and experience that goes into all of this. We do look at clinical trials and statistical models, but it’s important to understand what those numbers actually mean.
When we talk about averages from a trial, that’s exactly what they are — averages. Usually, you’re seeing averages from large groups of people, and so the average doesn’t predict what will happen to any one person. It simply reflects the middle of a wide range. Half the people in that group did better than that number, and half did worse. Very few people actually match it exactly.
Often, people see numbers like that online and want to know how they apply. I try to explain what an average represents and why it doesn’t predict what will happen for any one person. It’s useful information, but it’s limited.
In earlier-stage disease, we can’t directly measure whether a treatment is working, so statistical models can be more helpful. In more advanced disease, we learn a lot as we go. I usually tell people that we’ll know much more after the first scan. I may think a treatment is likely to work, but I can’t promise it. If the cancer responds and you feel better, that gives us important information. If it doesn’t, we reassess quickly. Prognosis is something you keep refining as new information comes in.
I often describe this as a journey. At the very beginning, there’s no way for me to tell you exactly what’s going to happen at the end. There are too many variables, and there are too many points along the way where things can change.
As we move through treatment, there are what I call branch points. You start a therapy, and we don’t know yet if you’re going to be someone whose tumor responds well or not. Then we get new information — scans, symptoms, how you’re feeling — and that changes what we think is likely going forward.
You can think of it as a road. You may not be able to see what’s around the next corner as you move forward, but when you get to certain points, you can see that either you have a long stretch ahead or you don’t. Each scan is like that — it gives us new information, but you don’t know what it’s going to show until you get there.
Longevity vs. Quality of Life
Another important point is that when I talk about prognosis, I’m not just thinking about how long someone with lung cancer might live. I’m also thinking about how they’re going to feel during that time.
What we’re trying to do is help people live as long as possible while feeling as well as possible. Those two goals always go hand in hand. Sometimes they line up, and sometimes they don’t. There are situations where a more aggressive treatment might be more likely to work but could also have more side effects. Other times, a less aggressive approach might better preserve quality of life.
So, it’s important for me to understand what matters most to each person I see. You might want to pursue every possible option, or you might be more focused on maintaining your day-to-day life as it is now. There isn’t a single right approach, but those choices should guide decisions.
We also have to be willing to talk about when it might make sense to stop treatment. If you never talk about it, it will never feel OK to bring up. But if you do talk about it, it’s more likely you can reach a point where you say: This is no longer a quality of life that’s meaningful for me.
There’s also the reality that new treatments are being developed all the time. I have patients who are alive today receiving therapies that didn’t exist when they were first diagnosed. That’s something we can’t fully account for at the beginning.
Living With Uncertainty
In my experience, people with lung cancer want a number for a prognosis, but at the same time, they don’t. If you give someone a number that turns out to be too short, they live with undue stress. If you give a number that turns out to be too optimistic, that can be just as hard because they cannot prepare well.
What I try to do instead is help people understand the range and probabilities, and then think about how to live within that uncertainty. That often means thinking in both directions at the same time.
What if things don’t go well? Have you taken care of the things that matter — your family, your finances, the things you want to say or do? And at the same time, what if you have longer than you expect? Are you leaving room to continue living your life, to make plans, to hold onto that possibility?
Prognosis isn’t a number. It’s an estimate based on what we know now, and it changes as we learn more. My job is to help guide people with lung cancer through that uncertainty, to keep adjusting as new information comes in, and to support them in making decisions that fit what matters most, while recognizing that we can’t see the whole road ahead.
