Final answer:
An oncologist is a medical specialist who focuses on diagnosing and treating malignant tumors. They use various treatment methods to manage and combat cancer.
Step-by-step explanation:
An oncologist is a medical specialist who is particularly concerned with malignant tumors and their treatment. They diagnose and treat various types of cancer, including solid tumors and blood-related cancers. Oncologists use a variety of treatment methods, such as surgery, chemotherapy, radiation therapy, and immunotherapy, to manage and combat cancer.