Delayed Adrenal Insufficiency After Nivolumab for Stage IV Lung Cancer

What happened, in summary

A 73-year-old man had been diagnosed 3 years earlier with Stage IV lung adenocarcinoma. Testing reported no mutations in EGFR, ALK, or ROS1. He completed 4 cycles of gemcitabine, vinorelbine, and nivolumab 7 months before a later hospital admission. A colorectal cancer resected 16 years earlier remained a separate part of his medical history.

He then developed 3 months of worsening weakness, poor appetite, fatigue, and a 30-pound unintentional weight loss. He also had cough, shortness of breath, back and joint pain, muscle aches, memory problems, and insomnia. On admission, his blood pressure was in the 70s to 80s over the 40s, with marked drops when he sat or stood.

Testing showed central adrenal insufficiency caused by isolated adrenocorticotropic hormone deficiency. The delayed timing supported an immune-related complication from nivolumab. He started hydrocortisone 20 mg in the morning and 10 mg in the evening, with fludrocortisone 0.1 mg for persistent orthostatic hypotension.

Within days, his symptoms improved dramatically. He completed a short inpatient rehabilitation stay and returned home independently. At follow-up, he had regained weight and no longer reported fatigue, weakness, or orthostatic symptoms; fludrocortisone was discontinued.