Which type of tumor does not spread into surrounding tissue?

The type of tumor that does not spread into surrounding tissue is benign tumors. Benign tumors are characterized by their non-invasive nature; they grow locally without invading neighboring tissues or metastasizing to distant parts of the body. Typically, benign tumors are well-circumscribed, which means they have defined boundaries, making them easier to remove surgically if needed. While they can cause problems depending on their size and location, they tend to pose less of a threat compared to malignant tumors.

In contrast, malignant tumors have the ability to invade nearby tissues and can break away and spread to other parts of the body through the bloodstream or lymphatic system. Carcinoma and sarcoma are specific types of malignant tumors, with carcinomas originating from epithelial tissues and sarcomas arising from connective tissues. Both types can metastasize and therefore significantly differ from the non-invasive nature of benign tumors.