Non-small Cell Lung Cancer
Non-small cell lung cancer (NSCLC) refers to various subtypes that have similar approaches to treatment and prognosis, though they have different chemical make-ups. All of the subtypes grouped together account for about 85-90% of lung cancer cases. Subtypes include:
- Squamous Cell Carcinoma
This subtype accounts for about 25% of lung cancer. It arises from squamous cells which are flat cells that line the inside of the bronchial tubes in the center of the lungs. Strongly linked to a history of smoking.
This is the most common subtype of lung cancer found in smokers and non-smokers comprising about 40% of all lung cancer. It typically occurs in the periphery of the lung and arises from alveolar cells that secrete mucus and other substances. Patients can have a better prognosis, as it tends to grow slower and there is a higher likelihood it can be found before it spreads to other parts of the body.
- Large Cell Carcinoma
It accounts for 5-10% of all lung cancer. It shows no evidence of squamous or glandular maturation and is often diagnosed through exclusion of the other subtypes. It can appear in any part of the lung, and grows and spreads quickly. This can make early diagnosis and treatment difficult. It behaves similarly to small cell lung cancer.
Other types of cancer that develop in the lung include:
Lung Carcinoid Tumors: These account for <5% of lung tumors, develop from neuroendocrine cells and can secrete hormone-like substances. Typical Carcinoid tumors are slow-growing, are amenable to complete surgical resection and usually have better prognosis. They only rarely metastasize beyond the lungs. Atypical Carcinoid tumors are less common, more aggressive and likely to metastasize.
Large Cell Neuroendocrine Carcinoma: This is a fast growing type of cancer four times more common in men than in women.
Lymphomas, sarcomas, hamartomas, adenoid cystic carcinomas: these are rare and each treated differently.