Pulmonary salivary gland-type tumors with features of malignant mixed tumor (carcinoma ex pleomorphic adenoma): a clinicopathologic study of five cases

We report 5 cases of pulmonary salivary gland-type tumors with features of carcinoma ex pleomorphic adenoma. Patient ages ranged from 44 to 71 years (mean, 53.8 years); 4 patients were men and 1 was a woman. In all 5 cases, the lesions were associated with the bronchial system. None of the patients had a history of a head and neck salivary gland neoplasm. Histologically, the lesions were invasive tumors containing malignant myoepithelial elements and duct-like structures embedded in a benign chondromyxoid stroma. Areas reminiscent of residual pleomorphic adenoma were noted in 2 cases. Follow-up for 3 patients revealed that 2 died 22 and 54 months after diagnosis and 1 was alive 20 months after diagnosis. The cases are characterized by unique morphologic features that, coupled with their immunoprofile, suggest the possibility that these tumors represent carcinoma ex pleomorphic adenoma, an entity that has not been well documented in the bronchopulmonary system.