Which types of cancer are included in non-small-cell lung cancer?

Non-small-cell lung cancer (NSCLC) comprises the majority of lung cancer cases and is primarily categorized into three distinct types of tumors:

• Adenocarcinoma: This is the most common form of lung cancer in the United States, accounting for approximately 40 percent of cases. These tumors are characterized by cube- or column-shaped cells that often form gland-like structures and typically originate in the smaller, peripheral bronchi.1
• Squamous cell carcinoma: Also known as epidermoid carcinoma, this type accounts for about 25 to 30 percent of primary lung cancers. It is characterized by flat, scalelike cells and usually develops in the larger bronchi of the central lung area.1
• Large-cell carcinoma: Representing about 10 percent of all lung cancers, these tumors can begin in any part of the lung and tend to grow rapidly. There is ongoing scientific debate regarding whether these represent a distinct cancer type or a group of unusual adenocarcinomas and squamous cell carcinomas.1