Rationale: Nasal-type, extranodal natural killer (NK)/T-cell lymphoma is a rare lymphoma. The tumor usually shows ulcerative and necrotic lesions in the nasal cavities and sinuses. Tissue involvement outside the nasal cavity is uncommon. Patient concern: We describe a 30-year-old man with a 2-month history of hoarseness, weight loss, and dyspnea. Diagnosis: Magnetic resonance image (MRI) showed edema of the larynx with obliteration of the airway. Laryngoscopic examination described necrotic tissue in the glottis and larynx. The biopsy showed chronic, necrotizing laryngitis, with no granulomas, vasculitis, or atypical cells. The immunologic and microbiologic study was negative. Later, after immunosuppressive therapy, the patient presented erythema and diffuse enlargement of the right arm. MRI showed myositis of the biceps and brachial muscles. Infection was rule out, and direct microscopy showed an extensive muscle infiltration by mononuclear cells and abundant mitosis. Immunohistochemistry was positive for CD3, CD8, Ki 67 (90%), and CD56 compatible with extranodal NK/T cell lymphoma. Interventions: The patient initially received immunosuppression treatments (corticoids, cyclofosfamide, and Rituximab) with relapsing episodes. When lymphoma was diagnosed, chemotherapy was started. Outcomes: The patient died during chemotherapy. Lessons: Nasal-type, extranodal NK/T-cell lymphoma should be suspected even when there are no classical findings of neoplasms on histology. Immunohistochemistry is mandatory to rule it out.