Not every round spot on a radiological image is a solitary pulmonary<unk> : it may be confused with the projection of a structure of the chest wall or skin, such as a nipple, a healing rib fracture or electrocardiographic monitoring. The most important cause to exclude is any form of<unk>  cancer, including rare forms such as primary pulmonary lymphoma, carcinoid tumor and a solitary metastasis to the<unk>  (common unrecognised primary tumor sites are melanomas, sarcomas or testicular cancer). Benign tumors in the<unk>  include hamartomas and chondromas. The most common benign coin lesion is a granuloma (inflammatory<unk> , for example due to tuberculosis or a fungal infection, such as Coccidioidomycosis. Other infectious causes include a<unk>  abscess, pneumonia (including pneumocystis pneumonia) or rarely nocardial infection or worm infection (such as dirofilariasis or dog heartworm infestation).<unk> s can also occur in immune disorders, such as rheumatoid arthritis or granulomatosis with polyangiitis, or organizing pneumonia. A solitary<unk>  can be found to be an arteriovenous malformation, a hematoma or an infarction zone. It may also be caused by bronchial atresia, sequestration, an inhaled foreign body or pleural plaque.
Lung nodule
Lung abscess
Pulmonary consolidation
Lung tumor
Pleural disease
Mediastinal tumors
Pulmonary infiltrate
Malignant pleural effusion