Immunotherapy May Be Overused in Dying Cancer Patients

Chemotherapy has fallen out of favor for treating cancer toward the end of life. The toxicity is too high, and the benefit, if any, is often too low.

Immunotherapy, however, has been taking its place. Checkpoint inhibitors are increasingly being initiated to treat metastatic cancer in patients approaching the end of life and have become the leading driver of end-of-life cancer spending.

This means “there are patients who are getting immunotherapy who shouldn’t,” said Yale University, New Haven, Connecticut, surgical oncologist Sajid Khan, MD, senior investigator on a recent study that highlighted the growing use of these agents in patients’ last month of life.

What’s driving this trend, and how can oncologists avoid overtreatment with immunotherapy at the end of life?

The N-of-1 Patient

With immunotherapy at the end of life, “each of us has had our N-of-1” where a patient bounces back with a remarkable and durable response, said Don Dizon, MD, a gynecologic oncologist at Brown University, Providence, Rhode Island.

He recalled a patient with sarcoma who did not respond to chemotherapy. But after Dizon started her on immunotherapy, everything turned around. She has now been in remission for 8 years and counting, he said.

The possibility of an unexpected or remarkable responder is seductive. And the improved safety of immunotherapy over chemotherapy adds to the allure.

Meanwhile, patients are often desperate. It’s rare for someone to be ready to stop treatment, Dizon said. Everybody “hopes that they’re going to be the exceptional responder.”

At the end of the day, the question often becomes, “Why not try immunotherapy? What’s there to lose?”

This thinking may be prompting broader use of immunotherapy in late-stage disease, even in instances with no US Food and Drug Administration indication and virtually no supportive data, such as for metastatic ovarian cancer, Dizon said.

Back to Earth

The problem with the hopeful approach is that end-of-life turnarounds with immunotherapy are rare, and there’s no way at the moment to predict who will have one, said Laura Petrillo, MD, a palliative care physician at Massachusetts General Hospital, Boston.

Even though immunotherapy generally comes with fewer adverse events than chemotherapy, catastrophic side effects are still possible.

Petrillo recalled a 95-year-old woman with metastatic cancer who was largely asymptomatic.

She had a qualifying mutation for a checkpoint inhibitor, so her oncologist started her on one. The patient never bounced back from the severe colitis the agent caused, and she died of complications in the hospital.

Although such reactions with immunotherapy are uncommon, less serious problems caused by the agents can still have a major impact on a person’s quality of life. Low-grade diarrhea, for instance, may not sound too bad, but in a patient’s daily life, it can translate to six or more episodes a day.

Even with no side effects, prescribing immunotherapy can mean that patients with limited time left spend a good portion of it at an infusion clinic instead of at home. These patients are also less likely to be referred to hospice and more likely to be admitted to and die in the hospital.

And with treatments that can cost $20,000 per dose, financial toxicity becomes a big concern.

In short, some of the reasons why chemotherapy is not recommended at the end of life also apply to immunotherapy, Petrillo said.

Prescribing Decisions

Recent research highlights the growing use of immunotherapy at the end of life.

Khan’s retrospective study found, for instance, that the percentage of patients starting immunotherapy in the last 30 days of life increased by about fourfold to fivefold over the study period for the three cancers analyzed — stage IV melanoma, lung, and kidney cancers.

Among the population that died within 30 days, the percentage receiving immunotherapy increased over the study periods — 0.8%-4.3% for melanoma, 0.9%-3.2% for NSCLC, and 0.5%-2.6% for kidney cell carcinoma — prompting the conclusion that immunotherapy prescriptions in the last month of life are on the rise.

Prescribing immunotherapy in patients who ultimately died within 1 month occurred more frequently at low-volume, nonacademic centers than at academic or high-volume centers, and outcomes varied by practice setting.

Patients had better survival outcomes overall when receiving immunotherapy at academic or high-volume centers — a finding Khan says is worth investigating further. Possible explanations include better management of severe immune-related side effects at larger centers and more caution when prescribing immunotherapy to “borderline” candidates, such as those with several comorbidities.

Importantly, given the retrospective design, Khan and colleagues already knew which patients prescribed immunotherapy died within 30 days of initiating treatment.

More specifically, 5192 of 71,204 patients who received immunotherapy (7.3%) died within a month of initiating therapy, while 66,012 (92.7%) lived beyond that point.

The study, however, did not assess how the remaining 92.7% who lived beyond 30 days fared on immunotherapy and the differences between those who lived less than 30 days and those who survived longer.

Knowing the outcome of patients at the outset of the analysis still leaves open the question of when immunotherapy can extend life and when it can’t for the patient in front of you.

To avoid overtreating at the end of life, it’s important to have “the same standard that you have for giving chemotherapy. You have to treat it with the same respect,” said a community medical oncologist with Alliance Cancer Specialists in Philadelphia, Moshe Chasky, MD. “You can’t just be throwing” immunotherapy around “at the end of life.”

While there are no clear predictors of risk and benefit, there are some factors to help guide decisions.

As with chemotherapy, Petrillo said performance status is key. Petrillo and colleagues found that median overall survival with immune checkpoint inhibitors for advanced non–small cell lung cancer was 14.3 months in patients with an Eastern Cooperative Oncology Group performance score of 0-1 but only 4.5 months with scores of ≥ 2.

Khan also found that immunotherapy survival is, unsurprisingly, worse in patients with high metastatic burdens and more comorbidities.

“You should still consider immunotherapy for metastatic melanoma, non–small cell lung cancer, and renal cell carcinoma,” Khan said. The message here is to “think twice before using” it, especially in comorbid patients with widespread metastases.

“Just because something can be done doesn’t always mean it should be done,” he said.

At Yale, when Khan works, immunotherapy decisions are considered by a multidisciplinary tumor board. At Mass General, immunotherapy has generally moved to the frontline setting, and the hospital no longer prescribes checkpoint inhibitors to hospitalized patients because the cost is too high relative to the potential benefit, Petrillo explained.

Still, with all the uncertainties about risk and benefit, counseling patients is a challenge. Dizon called it “the epitome of shared decision-making.”

Petrillo noted that it’s critical not to counsel patients based solely on the anecdotal patients who do surprisingly well.

“It’s hard to mention that and not have that be what somebody anchors on,” she said. But that speaks to “how desperate people can feel, how hopeful they can be.”

The physicians interviewed for this story had no relevant disclosures.

M. Alexander Otto is a physician assistant with a master’s degree in medical science and a journalism degree from Newhouse. He is an award-winning medical journalist who worked for several major news outlets before joining Medscape Medical News. Alex is also an MIT Knight Science Journalism fellow. Email: aotto@mdedge.com