Specific structure of adenoid cystic carcinoma of the lung, usually not too difficult diagnosis. Note the time of diagnosis the tumor with the following differences.
differential diagnosis of adenoid cystic carcinoma metastatic adenoid cystic carcinoma (metastatic ACC): The size of the salivary glands occurred outside the lung, the late occurrence of lung metastases. Morphology in tumor tissue is not differentiated metastatic ACC, should be found in the primary tumor, such as the parotid gland, leading swollen glands and other parts of the second place, attention to primary pulmonary ACC in the central area of lung, and metastatic ACC, can be multi-tool, the tumor was no clear relationship with the bronchial tree.
the differential diagnosis of adenoid cystic carcinoma of the lung adenocarcinoma with cribriform structure: common type of lung cancer can have a sieve-like local area structure, the diagnosis should be distinguished. Identification of key points: a. lung cancer with focal or regional structure, the most common type of lung cancer is, bamboo-like cancer or papillary carcinoma, clear cell atypia, but rather a specific structure of the lung ACC , the cancer is small, mildly abnormal; b. Immunohistochemistry: ACC for EMA, S-100 protein and were positive for actin expression in lung adenocarcinoma with sieve-like structure only on the EMA, CEA expression was positive in myogenic markers and S-100 protein should be negative.
Differential diagnosis of adenoid cystic carcinoma SCLC: bronchoscopy small biopsy specimens, ACC showed similar small round cell tumor. Identification of the two main points: a.ACC nuclear chromatin and nuclear type and the phase shows that the former SCLC heterogeneity; b. SCLC is more common human extrusion, or see a bad slice of total tumor type can be found in cylindrical or sieve-like structure; c.SCLC more than nuclear fission, nuclear fission or no less; d. mucus staining: ACC mucus droplets within the cytoplasm is easy to see, SCLC with no or rare within the mucus droplets; e. Immunohistochemistry: SCLC neuroendocrine antibodies INSE, wrong grain Su A (ChromograinA CgA), synaptophysin. Negative for neuroendocrine markers ACC, while the binding protein, SM-muscle the lowest white, EMA, S-100 protein positive; f. electron microscopy: ACC acinar cells were on the W, the ultrastructure of myoepithelial differentiation, no neurosecretory granules, liquid particles can have hope. LC number within the cytoplasm, ranging from neurosecretory granules.