Carcinomas and sarcomas are two main types of tumors. They are different based on where they start in the body, how they look under a microscope, and how they act.

What are Carcinomas?

• Where They Come From: Carcinomas start in epithelial cells. These cells are found on the surfaces of organs and body cavities. Carcinomas make up about 80-90% of all cancer cases.
• How They Grow: They usually grow in a messy way. For example, adenocarcinomas (a type of carcinoma) can form irregular glands.
• Cell Features: The cells often have big nuclei (the parts of the cell that contain DNA). They also have more nuclei compared to the rest of the cell and show unusual cell division.
• Spreading: Carcinomas can invade nearby tissues and spread to other parts of the body. About half of the people with solid tumors have some spread of cancer when they are diagnosed.
• Types: Some common types are squamous cell carcinoma, adenocarcinoma, and transitional cell carcinoma.

What are Sarcomas?

• Where They Come From: Sarcomas start in mesenchymal tissues. These are also known as connective tissues like bones, cartilage, fat, and muscles. Sarcomas are much rarer, making up about 1% of adult cancers.
• How They Grow: They usually look more cellular and can have stretched or irregularly shaped cells.
• Extra Material: Sarcomas often have a noticeable amount of extracellular matrix. This is the material that surrounds the cells and can look different in different sarcomas.
• Spreading: Sarcomas tend to spread through the bloodstream. They are not as common as carcinomas, and for advanced cases, about 15-20% of people survive for five years.

In short, carcinomas and sarcomas are quite different from each other. They have unique features and come from different types of cells in the body.