| Oncocytoma |
Undetectable on X-ray or CT |
Solitary polypoid nodules ranging from 1.0–3.5 cm in diameter |
Uniform large polygonal cells with eosinophilic cytoplasm and small round nuclei forming sheets, trabeculae, acinar structures |
| Mucus gland adenoma |
Undetectable on X-ray or CT |
Solitary polypoid nodules |
Mucous gland adenoma cells appear as cystic mucus-filled glands on microscope |
| Adenoid cystic carcinoma |
Detectable on chest X-ray and CT scan; Positive PET-CT scans (6–10% of cases) |
Nodular or vascular lesions; ice-berg structure with wide base and narrow intraluminal projection of nodular or lobulated |
Monomorphic uniform cells with scant cytoplasm. Three histological subtypes including tubular, cribriform and solid (most aggressive type) Tissue stains positive with, keratin, CK7, CD117S-100, and SMA |
| Mucoepidermoid |
Sharply marginated, ovoid or lobulated polypoid nodules on chest X-ray described as “pneumonic consolidation” and “punctuate calcifications”; CT findings similar to those of the bronchial carcinoid tumors but less enhancement due to less vasculature |
Smooth, well-circumsized glossy lesion with no visible vessels |
Tissue analysis consistent with variable proportions of mucus-secreting cells, squamous cells, and so-called intermediate cells that show no particular differentiating characteristics |
| Myoepithelial carcinoma |
Opaque shadow with well-circumcised borders on radiological chest X-ray and CT scan |
Smooth, well-circumsized endobronchial mass with clear borders, spontaneous bleeding to touch |
Glandular differentiation with a dual population of epithelial and myoepithelial cells; Tissue stains positive for p53 and c-Kit (CD117);focal atypia and increased mitotic activity can be present |
| Papilloma |
Abnormal shadows or infiltrates on chest X-ray; Focal bronchiectasis is a common radiographic feature |
Polypoid or pedunculated friable tan to red, glistering, no visible vessels, no spontaneous bleeding |
Tissue analysis consistent with intracellular mucin which is positive for MUC5AC (expressed in goblet cells); columnar cells which are diffusely positive for CAM5.2 and CK19; CEA and CA19-9 are focally positive |
| Carcinoid tumor |
Well-defined spherical or ovoid nodule with a slightly lobulated border on CT scan; Vascular enhancement on CT scanVariable uptake on FDG and PET-CT compared to other malignant tumors depending on the mitotic figures |
Large fleshy polypoidal growth with well-defined narrow stalk arising from the luminal wall |
Tissue stains positive for chromogranin and synaptophysin and negative for smooth-muscle actin antibodies; Intracytoplasmic dense-core granules seen under electron microscope |
| Leiomyoma |
Detectable lesions on X-ray, specially lateral view; CT scan helps confirm the size and extent of the tumor |
Smoothly contoured, polypoid mass pink in color with broad base, rare spontaneous bleeding |
Tissue analysis consistent with pseudostratified columnar epithelium; bundles and whorls of spindle shaped cells with monomorphous fusiform nuclei and acidophilic cytoplasm; Tissue stains positive for desmin and caldesmon |
| Schwannoma |
Spherical and slightly heterogeneous lesions on CT or MRI |
Smooth, round, whitish color mass with no visible vessels, no spontaneous bleeding |
Tissue analysis consistent with presence of a capsule, presence of compacted bipolar cells with nuclei arranged in a palisade form and/or loosely arranged spindle cells within myxoid matrix and positive staining for S-100 |
| Hamartoma |
Variable findings on CT scan such as internal fat or “popcorn” calcifications; Little to no uptake on FDG PET-CT |
Round, pink mass with no visible vessels, not spontaneous bleeding |
Tissue analysis consistent cartilage, fat, fibrous tissue, and epithelial components |
| Hemangioma |
X-ray can detect lesions depending on size and location |
Polypoid lesion with visible vessels, usually appear hemorrhagic |
Tissue analysis consistent with benign lobular capillary hemangioma |
| Lipoma |
Enlarged hilar shadow, or atelectatic pattern on chest X-ray |
Soft, poorly vascular, white, or yellowish glistening mass |
Definitive diagnosis in fewer than 50% of biopsies due to existence of a fibrous, firm sheath around the tumor which may prevent adequate tissue sampling |
| Chondroma |
Lobar consolidation or atelectasis on chest X-ray |
Pedunculated, vascularized, pink lesions |
Biopsies shows characteristic chondromatous tissue |
| Glomus tumor |
Distinguished from other tumors on CT scan based on smooth borders and marked contrast enhancement due to their rich vascular supply |
A mass with hyperemic, meaty or flesh solid surface on gross bronchoscopic visualization |
Tissue analysis consistent with medium-sized cells with round nuclei and eosinophilic cytoplasm; arranged in sheets that form collars around capillary sized vessels; Tissue stains positive for smooth muscle actin and vimentin |
| Granular cell tumor |
Detectable airway masses on CT scan |
Pedunculated polypoid endobronchial lesion partially obstructing the bronchial lumen |
Tissue analysis consistent with granular cells that stain positive for S-100 but negative for smooth muscle, calretinin and inhibin |
| Endobronchial T-cell lymphoma |
Chest CT imaging reveal an endobronchial mass. PET avid endobronchial lesion |
Obstructing bronchial lesion |
Positive for CD3, CD4, and CD5 and negative for CD8 and CD20 |
| Fibrosarcoma |
Well-marginated, smooth or lobular nodules or masses on X-ray or CT; They can also manifest as atelectasis or postobstructive pneumonitis |
Multi-nodular mass, usually manifesting as endobronchial atelectasis or post-obstructive pneumonitis |
Closely packed spindle cells in herringbone pattern |
| Chondrosarcoma |
Large chest wall masses with bone destruction and soft-tissue involvement on CT; Scattered areas of calcification in the chondroid matrix detected with CT. Intermediate signal intensity on T1-weighted MR images and are heterogeneous on T2-weighted images, typically with scattered areas of high signal intensity |
Polypoid endotracheal or endobronchial masses on bronchoscopy |
Tissue analysis consistent with moderately hypercellular cartilaginous and binuclear cells with large nuclei and open chromatin; mitotic figures were absent |
| Inflammatory myofibroblastic tumors |
Non-specific obstructive lesions on chest X-ray and CT scan |
Smooth-surfaced, lobulated mass lesion with visible vessels, spontaneous bleeding |
Tissue stains positive for vimentin, muscle-specific actin, SMA and ALK-1 (up to 60% cases) |
| SEPs |
Solitary nodule, lobar consolidation or as diffuse pulmonary infiltrate on chest X-ray or CT scan |
Smooth-surface mass 1–2 cm in size |
Tissue analysis consistent with kappa chain-type and lambda chain-type tumors; Diagnosis is based on 5 criteria including single extramedullary mass of clonal plasma cells, histologically normal bone marrow, absence of anemia, normal skeletal survey and lack or decrease in serum or urinary level of monoclonal immunoglobulin |
