Abstract
BACKGROUND: Acute invasive fungal infections of the head and neck secondary to tyrosine kinase inhibitors are rare and potentially life-threatening events. CASE PRESENTATION: We report a case of mucormycosis of the thyroid gland in a patient known for chronic lymphocytic leukemia receiving ibrutinib who presented with a rapidly growing thyroid nodule and dysphonia. An acute invasive fungal infection was identified on a core needle biopsy; mucormycosis was confirmed on culture. The patient was successfully treated with surgical debridement and long-term antifungal therapy. CONCLUSION: Patients on ibrutinib may be at risk of acute invasive fungal infections of the head and neck.