BACKGROUND. Primary lung tumors showing features of salivary gland-type neoplasms are extremely rare. METHODS. Eight patients with primary lung neoplasms showing light microscopic and immunohistochemical features of salivary gland-type mixed tumors were studied. RESULTS. The patients were six women and two men, ages 35-69 years (mean, 52.5 years). The tumors ranged from 2 to 16 cm in greatest diameter. In two patients the lesions presented as polypoid endobronchial lesions obstructing the lumen; in another two patients the lesions were found in close proximity or in continuity with a bronchus; in three patients, the lesions presented as peripheral parenchymatous nodules unrelated to a bronchus; and in one patient, the relationship to the bronchus could not be determined. Histologically, the lesions were biphasic, showing admixtures in varying proportions of epithelial elements containing a predominant myoepithelial cell population with a stromal component containing an abundant myxoid or focally chondroid matrix. Immunohistochemical studies showed strong positivity of the cells in the epithelial component with low molecular weight keratins (CAM 5.2), and to a lesser extent with broad spectrum keratin, actin, and vimentin antibodies. The cells also showed variable reactivity in the epithelial and nonepithelial elements with S-100 protein and glial fibrillary acidic protein. Six tumors were grossly and histologically benign; in two patients, the tumors were larger, locally invasive, and showed more atypical histologic features. All patients were treated with surgical excision. On follow-up, of the six patients with histologically benign-appearing tumors, one was alive and well 6 years after surgery; another died 4 years after surgery of a second unrelated malignancy; one died during the immediate postoperative period of myocardial infarction; and three have been lost to follow-up. In the two patients with histologically atypical lesions, the tumors recurred and metastasized after 2 and 3 years, respectively, with one of them leading to death caused by widespread metastases and superior vena cava syndrome. CONCLUSIONS. Review of the literature and the findings in the current series indicate that salivary gland-type mixed tumors of the lung may present with a spectrum of histologic features and clinical behavior, ranging from benign to frankly malignant, similar to that observed for their salivary gland counterparts. Size of the lesion at the time of presentation, extent of local infiltration, and degree of mitotic activity appear to be the most reliable prognostic features of these tumors.

A case of salivary gland-type mixed tumor of the lung differentiating toward type II alveolar epithelial cells in glandular components with a literature review.Virchows Arch. 2002 Dec;441(6):618-21. Epub 2002 Jun 26.

Salivary gland-type mixed tumor primarily arising in the lung is extremely rare. We report here a case of this type of tumor that occurred in the periphery of S4 of the right middle lobe in a 74-year-old man. Light-microscopically, this lung tumor, 15x9mm in size, exhibited almost the same features as those of mixed tumor of the salivary gland intermingled with chondromyxoid stroma, glandular component, solid growth pattern of myoepithelial components and well-developed cartilage formation, exhibiting a sharp margin. Immunohistochemical study revealed that the glandular components in the tumor was positive for thyroid transcription factor-1, TTF-1, a marker of epithelial cells of the thyroid as well as the lung. Furthermore, surface lining cells of the glandular components and luminal contents were positive for surfactant apoprotein A, PE-10, used as a marker of type II alveolar epithelial cells. These findings clearly demonstrate for the first time that glandular epithelial cells in the present salivary gland-type mixed tumor exhibited differentiation toward type II alveolar epithelial cells.

Malignant mixed tumor of bronchus: a biphasic neoplasm of epithelial and myoepithelial cells.Mod Pathol. 1993 Jan;6(1):85-8.

This paper describes an unusual malignant mixed tumor of the bronchus arising in a 71-yr-old male and provides evidence of an epithelial-myoepithelial origin based on the findings on light microscopy and immunohistochemistry. The neoplasm contained elements of recognizable benign tumor resembling salivary gland-type pleomorphic adenoma, adenosquamous carcinoma, and a spindle-cell sarcomatous component. Immunohistochemical stains showed the characteristic relationship between epithelial and myoepithelial cells in the benign component of the neoplasm. In addition, the spindle cells stained for myoepithelial markers (S-100 protein and actin) but were also positive for keratin (AE1/AE3). The relationship of this neoplasm to classical carcinosarcoma and the recently described adenosquamous carcinoma with amyloid-like stroma is discussed.

Normal Anatomy and Histology of the Lung and Airways

Anatomical Distribution of Pulmonary Disease

Useful chromatic and immunostains in pulmonary pathology

Percutaneous Needle and Trucut Biopsy Specimen:

Bronchial Biopsy Specimen:

Transbronchial Biopsy Specimen:

Transbronchial biopsy in lung transplant recipients:

Lobectomy and pneumonectomy specimen

Histopathological reporting of pulmonary parenchymal biopsies:

Closed pleural biopsy ; Open pleural biopsy:

Congenital Cystic Adenomatoid  Malformation

Acute Respiratory Distress Syndrome