<unk> , also known as<unk>  carcinoma, since about 98–99% of all<unk> s are carcinomas, is a malignant<unk>  tumor characterized by uncontrolled cell growth in tissues of the<unk> .<unk>  carcinomas derive from transformed, malignant cells that originate as epithelial cells, or from tissues composed of epithelial cells. Other<unk> s, such as the rare sarcomas of the<unk> , are generated by the malignant transformation of connective tissues (i.e. nerve, fat, muscle, bone), which arise from mesenchymal cells. Lymphomas and melanomas (from lymphoid and melanocyte cell lineages) can also rarely result in<unk> . In time, this uncontrolled growth can spread beyond the<unk>  – either by direct extension, by entering the lymphatic circulation, or via the hematogenous, bloodborne spread – the process called metastasis – into nearby tissue or other, more distant parts of the body. Most cancers that start in the<unk> , known as primary<unk> s, are carcinomas. The two main types are small-cell<unk>  carcinoma (SCLC) and non-small-cell<unk>  carcinoma (NSCLC). The most common symptoms are coughing (including coughing up blood), weight loss, shortness of breath, and chest pains. The vast majority (85%) of cases of<unk>  are due to long-term tobacco smoking. About 10–15% of cases occur in people who have never smoked. These cases are often caused by a combination of genetic factors and exposure to radon gas, asbestos, second-hand smoke, or other forms of air pollution.<unk>  may be seen on chest radiographs and computed tomography (CT) scans. The diagnosis is confirmed by biopsy, which is usually performed by bronchoscopy or CT-guidance. The major method of prevention is the avoidance of risk factors, including smoking and air pollution. Treatment and long-term outcomes depend on the type of cancer, the stage (degree of spread), and the person's overall health. Most cases are not curable. Common treatments include surgery, chemotherapy, and radiotherapy. NSCLC is sometimes treated with surgery, whereas SCLC usually responds better to chemotherapy and radiotherapy. Worldwide in 2020,<unk>  occurred in 2.2 million people and resulted in 1.8 million deaths. It is the most common cause of cancer-related death in both men and women. The most common age at diagnosis is 70 years. In most countries the five-year survival rate is around 10 to 20%, while in Japan it is 33%, in Israel 27%, and in the Republic of Korea 25%. Outcomes typically are worse in the developing world.
Lung cancer
Tracheobronchomalacia
Lung tumor
Foreign body aspiration
Kidney cancer
Chronic pulmonary aspergillosis
Heart cancer
Lung abscess