Summaries from medbulets.com
Overview of lung cancer
Lung cancer is divided into two histologic classes: non-small cell lung cancer (NSCLC), which accounts for 85% of lung cancer and small cell lung cancer (SCLC) which accounts for the remainder. There are three main types of NSCLC: adenocarcinoma (40%), squamous cell (30%), and large cell (15%). SCLC accounts for 15%. Adenocarcinoma is the most frequent type in women and non-smokers. As we will discuss, because most lung cancers are diagnosed late in the course of the disease, overall survival is a dismal 15%.
Squamous cell or epidemoid carcinoma tends to arise from central bronchi and is closely linked to cigarette smoking. The presence of keratin “pearls” reflects some degree of differentiation. Squamous cell carcinoma tends to metastasize late. Adenocarcinoma (now the most common type) forms acinar and glandular structures and occurs mostly in the periphery of the lung. More differentiated types are associated with formation of mucin. Large cell carcinoma is an anaplastic tumor devoid of evidence of glandular or squamous differentiation. The cells are bizarre in shape and the tumor generally arises in the periphery.