How do you know if cancer treatment is working?

This is the question I get asked the most: “So Doc, how do I know that this is working?” Sometimes my patients come to me with visible or palpable disease—something on the skin that they can see fading away, an enlarged lymph node in the neck that shrinks visibly during treatment, a lump or a bump that disappears, much to the gratification of both patient and doctor. But most of the time, this is not the case. Most of the time, the tumors are either deep inside, and not seen or felt, or the tumor has been removed, and we radiation oncologists are called in to do “clean up” work after the surgeon. As disturbing as it might be to a patient, most of the time, we don’t actually know that “it”, meaning the radiation, is working.

I’m old enough to know that life is not black or white, right or wrong, on or off. But still, as an optimist, I am a person who likes absolutes—I have always believed that if you play by the rules, you deserve to win. I dot all of my “I’s” and I cross my “T’s”. I was the kid who NEVER colored outside the lines in my coloring book, and now that I am a grown up, everything should be in place: my patients will attest to the fact that I am likely to rearrange the furniture in the consultation room if the cleaning people have set anything off kilter. I don’t see this as obsessive-compulsive—I see it as maintaining order in a disordered world. I like to see justice served, the plates cleared off after dinner, and I do not eat dessert first. In my linear world, the beginning is the consultation, the ending is the cure. The daily radiation treatments are the means to that end. Why should my patients expect less?

So what do I tell my patients who ask tentatively, half way through treatment, “Is it working?” when they have the invisible tumors, the ones deep inside, or the ones where the surgeon took most of it and we’re seeking out and destroying those microscopic stragglers? One of my teachers once said, meaning to be humorous, “Radiation works best when there is no disease!” Even the patients with the palpable masses that melted away—how can we be sure that every last malignant cell is gone? At the end of treatment, my patients want to be told that their disease has been vanquished and will never come back. Some doctors will oblige. They will say “We got it all”. Or they say, “You are cancer free.” This is despite the fact that there is not a single diagnostic test on the planet that can support that claim.

We oncologists prefer to use the word “remission.” Or “complete response.” As in, “You are in remission.” Or “You have had a complete clinical and radiographic response to treatment.” We would love to say, “Your cancer is cured,” because that is ever so much more satisfying than stating the truth, which is that we do not and cannot know for sure. Sometimes, somethings, some days—you just have to take it on faith and try to move on. Even if you are not a believer.

Here is what I tell my patients. I tell them that first the side effects will fade from their bodies and their memories. And then there will come a day when they will actually miss the camaraderie and support that they got from their chemotherapy and radiation teams. I tell them that the sun will rise and the sun will set, and they will bravely put one foot in front of the other. And one day, before they know it, they will wake up and stretch and smile and they will have forgotten, just in that moment, that they ever had cancer. And that’s when they will know, it worked.

Miranda Fielding is a radiation oncologist who blogs at The Crab Diaries

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    As someone 3-years out from radiation for breast cancer, I can tell you that there is no forgetting of a miserable experience — the too cheerful, pink-ribbon techs, the overly loud receptionist, the crabby oncologist, and the pain of radiation, that daily sensation of something crawling under my skin. I left knowing that this treatment might have been helpful, but there is no cure that can be defined and known. The magical thinking of the survivor model isn’t for me, and yes, I truly hope I never have to go through this again. Time will tell, but so far, no fading memories have put a gloss on the radiation experience.

    • Miranda Fielding

      I am truly sorry you had such a bad experience. I hope that you were given the opportunity to give constructive criticism of your experience. No one likes undergoing radiation or chemotherapy, but not all feel the way you do. I do hope that you are feeling well now.

      • BRYAN

        I did share my specific concerns, and a couple of improvements were made. And I finally got the techs to understand that I didn’t want the well-intended chit-chat –let’s just get this done. With that said, no one took the pain seriously because they all insisted that radiation is painless. But in talking with other patients then, and since then, many people experience unwelcome sensations including nerve pain, which may be from the awkward position and length of time the patient has to hold it, or the results of radiation itself. I asked the oncologist to sign off at my last session because I knew I wasn’t going back in 6 months or a year. Fortunately, the medical oncologist was a better choice for me — sensible, no bright-side thinking, no ribbons, and a good listener/responder. The only thing I learned from the radiation experience is that the patient really has to take charge, or the patient gets steamrolled into being a cancerous object — something tied down during the rack and beam portion, photographed, sometimes tattooed (I refused that part of the plan), and often overlooked as a person. I gutted it out and have never been back. Fortunately, I’m in a city with other clinic choices, and if I have to do this again, I’ll do my research instead of taking my physician’s referral. When my second cancer occurred, due to tamoxifen, I interviewed four gynecologic oncologists before making a choice, and that worked for me.

        I wish you all the best in your career. I suspect physicians are as varied as patients, and not every referral will be a good fit.

        • Miranda Fielding

          I do agree with you that the patients should take a very active role in their treatments and be happy in their choice of physicians, since the patient is the one who must live with the consequences. Thanks for your good wishes. Miranda

  • Windy53

    A beautifully written essay. I was treated with rads in early 2010 for Inflammatory Breast Cancer. So far, all is well. What you say is true in my experience–and I am, by nature, a pessimist. And I had anything BUT a smooth sail experience through treatments. It’s not like I’m some kind of polyanna. Far, far from it.
    Nevertheless, as time has passed and so far has remained so good, whole blocks of hours can pass when I am totally unaware that I had or might have cancer again. That’s the best medical science can give me. I wish it were more — I wish medical science could give me a 99% certain guarantee.
    But there seems to be little in life that gives me that. So I am learning, slowly, to be OK with what medical science can give me, try to determine how I can make it all better for the next generation of cancer patients, and life the best life I can, for now, knowing that for some cancer patients, the treatments do not, in fact, work.

    • Miranda Fielding

      Thank you for the compliment on my writing, and I am happy that you are doing so well. I wish you good health and happiness in the New Year.

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