Blastomycosis of the larynx.

Blastomycosis is a chronic fungal disease with a constellation of signs and symptoms and a variable course. It primarily affects the lower respiratory tract, although extrapulmonary manifestations are common. We describe 6 patients with blastomycosis of the larynx who represent 5.6% of 107 patients with blastomycosis seen at the Mayo Clinic from 1950 through 1981. When involvement of the larynx occurs, both gross and histopathologic findings of the lesion usually resemble the features of well-differentiated squamous cell carcinoma and often lead to misdiagnosis and inappropriate, overly aggressive, surgical or radiation therapy. So that this unnecessarily aggressive treatment of the diseased larynx can be avoided, we discuss the clinical features, histopathologic findings, diagnosis, and current forms of treatment of blastomycosis.