Painless thyroiditis syndrome associated with PD-1 treatment in patients with cancer
CORONADO, Calif. — A small subset of patients with metastatic malignancies who received immunotherapy with program death-1 receptor monoclonal antibodies have been shown to have a painless thyroiditis syndrome marked by transient thyrotoxicosis and hypothyroidism, according to a presentation here.
Paul G. Walfish, CM, O.Ont, MD, FRPC, and colleagues from the Joseph and Mildred Sonshine Family Centre for Head & Neck Diseases at Mount Sinai Hospital in Toronto, evaluated 10 patients with metastatic malignancies (malignant melanoma, n=7; non-small cell lung cancer, n=3; mean aged 55 years; 60% female) to determine the incidence of painless thyroiditis. All patients had received PD-1; all were referred to an outside clinic for diagnostic confirmation and treatment after reporting symptoms that were consistent with thyroid dysfunction.
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Paul G. Walfish
Sixty percent of patients were diagnosed with transient thyrotoxicosis and were treated with beta-blocker therapy. Among those patients, thyrotropin binding inhibitory immunoglobulins were negative, whereas 67% of patients had anti-thyroid antibodies documented.
After approximately 4 weeks, all patients’ thyrotoxicosis was resolved, although it was followed by hypothyroidism that required therapy with levothyroxine. All patients required hormone replacement therapy for a minimum of 6 months. No correlation was found in the patients between the oncologic response to immunotherapy and thyroid symptoms.
“In conclusion, we have demonstrated that immunotherapy with PD-1 receptor antibodies for metastatic malignancies can be accompanied by painless thyroiditis syndrome in a subset of susceptible patients,” Walfish said in a presentation. “Given the increasing application of immunotherapy for the treatment of a variety of malignancies, clinicians should monitor such patients for thyroid dysfunction.”
For more information:
Orlov S. Oral #12. Presented at: American Thyroid Association Annual Meeting; Oct. 29-Nov. 2, 2014; Coronado, Calif.
Disclosure: The researchers report no relevant financial disclosures.