A malignant neoplasm is a type of tumor that is cancerous. Unlike benign tumors, which do not spread to other parts of the body, malignant neoplasms can invade nearby tissues and organs. They can also metastasize, meaning they can travel through the bloodstream or lymphatic system to form new tumors in distant locations. Malignant neoplasms can arise in various parts of the body and are classified into different types, such as carcinomas, sarcomas, and leukemias. Early detection and treatment are crucial for improving outcomes, as these tumors can grow rapidly and may lead to serious health complications if not addressed promptly.