What Patients Should Know About Lifelong Endocrine Side Effects of Immunotherapy

Some patients treated with immunotherapy may develop lifelong endocrine conditions requiring ongoing hormone replacement, insulin therapy and long-term monitoring, according to Vivian Crowder, MSN, APRN, FNP-C, AOCNP, BC-ADM, of The University of Texas MD Anderson Cancer Center.

During a presentation at the 51st Annual Oncology Nursing Society (ONS) Congress, Crowder discussed how immune checkpoint inhibitors — a type of immunotherapy used to treat many cancers — can sometimes trigger immune-related endocrine disorders affecting the thyroid, adrenal glands, pituitary gland and pancreas.

“These are hard diagnoses to be able to carry for lifelong,” Crowder said in an interview with CURE®. “Making sure they’re plugged in, even with a social worker, and assessing what their family support is [is important] so that they don’t go into this state of consistent and utter depression because of these long-term consequences of their immunotherapy.”

Why endocrine side effects can be difficult to recognize

Immune checkpoint inhibitors work by helping the immune system attack cancer cells, but in some cases, the immune system may also attack healthy organs and glands.

According to Crowder, one challenge for oncology teams is recognizing when symptoms may signal an endocrine toxicity rather than routine treatment side effects.

“You have someone who has fatigue, abdominal pain, nausea or vomiting — yes, you can associate this with their actual treatment,” Crowder explained. “But if this is someone that you have already given every single thing to and they are still not getting better, please think: Is this toxicity from immunotherapy?”

She added that while some endocrine complications are rare, immune-related toxicities overall are not uncommon among patients receiving immunotherapy.

Which endocrine conditions Can occur?

Crowder’s presentation highlighted several possible endocrine toxicities linked to checkpoint inhibitors, including adrenal insufficiency, hypothyroidism, thyroiditis, hypophysitis and immune checkpoint inhibitor-induced diabetes mellitus (ICI-DM).

Symptoms may include:

• Severe fatigue
• Nausea and vomiting
• Abdominal pain
• Excessive thirst
• Frequent urination
• Weight changes
• Constipation
• Heat or cold intolerance
• Blood sugar abnormalities
• Headaches or vision changes

Some conditions may improve over time, but others can become permanent and require lifelong treatment.

For example, adrenal insufficiency often requires lifelong steroid replacement, while ICI-induced diabetes may require lifelong insulin therapy.

Family support is essential

Crowder emphasized that strong family support can make a major difference for patients adjusting to long-term endocrine conditions after cancer treatment.

“With the diagnosis of immune checkpoint inhibitor diabetes, this is an all-in family event,” Crowder said. “They need to understand when they go out to eat, their loved one needs to make sure that they’re checking their blood sugar, administering their insulin appropriately, and that they are able to recognize high blood sugars as well as low blood sugars.”

For patients with adrenal insufficiency, she said caregivers may need to help administer emergency steroid injections if patients cannot take oral medications.

“That steroid that they need for life is essential,” Crowder said.

She also encouraged patients and caregivers to communicate openly throughout survivorship care.

“Talk often, talk frequently and keep things very open,” Crowder said. “If the patient feels as though they have a partner, they have an ally in there, then at least they feel like someone can understand them, that they feel heard and that they have an outlet.”

Ongoing monitoring remains important

According to Crowder’s presentation, patients with endocrine toxicities may require regular blood work, endocrinology visits and long-term follow-up care.

Researchers are also continuing to study ways to better predict, prevent and detect endocrine side effects earlier in treatment.

As immunotherapy becomes increasingly common across cancer care, Crowder said continued education for patients, caregivers and healthcare teams remains critical.

References

1. “What to Know About Long-Term Endocrine Toxicities of Checkpoint Inhibitors” by Vivian Crowder, et al., presented at the 51st Annual Oncology Nursing Society Congress.