Final answer:
A biopsy is the surgical extraction of a tissue sample, which is then microscopically examined by a pathologist to diagnose conditions such as cancer and distinguish between different cancer types and subtypes.
Step-by-step explanation:
The term biopsy can be divided into two parts: 'bio-', meaning life, and '-opsy', meaning 'to see'. Essentially, a biopsy involves the surgical removal of tissue for examination.
A biopsy is vital for a definitive diagnosis of various conditions, including cancer. In this process, a sample of tissue is extracted and analyzed microscopically by a pathologist. This examination can uncover the presence of cancer and further classify it based on the originating tissue, such as carcinoma, which can originate from epithelial cells and include cancers of the skin, lung, breast, and colon.
Understanding the microscopic characteristics of cancer cells, such as their size and shape, can lead to important distinctions, informing the prognosis and treatment options. For instance, carcinomas of the lung are divided into small-cell and non-small-cell carcinomas, each requiring different treatment approaches.