What distinguishes malignant tumors from benign tumors?

Malignant tumors are characterized primarily as cancerous growths. This means they have the potential to spread to other parts of the body and can invade surrounding tissues, leading to more severe health consequences. Unlike benign tumors, which are non-cancerous and generally remain localized, malignant tumors can metastasize, moving through the lymphatic system or bloodstream to establish secondary tumors in distant organs.

In contrast, benign tumors typically grow slowly and do not invade nearby tissues or metastasize. They are often enclosed in a capsule, which makes them easier to remove surgically and less likely to cause significant systemic health issues. Thus, the defining feature of malignant tumors is their cancerous nature, which is critical for understanding the urgency and seriousness of treatment options in a clinical setting.