What is the histological feature commonly seen in squamous cell carcinoma of the lung?

The presence of keratin pearls is a hallmark histological feature of squamous cell carcinoma, particularly in the lung. These structures are formed when the squamous cells undergo keratinization, which is a process where cells become more fibrous and accumulate keratin, leading to the formation of concentric layers of keratinized cells. This characteristic is especially prominent in well-differentiated squamous cell carcinomas, where the tumor cells retain some of the normal squamous morphology, reflecting their origin from squamous epithelium.

In the context of lung cancer, squamous cell carcinoma arises from the bronchial epithelium and can be associated with smoking. The observation of keratin pearls under the microscope helps pathologists confirm a diagnosis of squamous cell carcinoma, differentiating it from other types of lung carcinoma that lack this feature. Understanding these histological characteristics is essential for proper cancer classification and treatment planning.