Medical oncology is a subdivision of internal medicine that deals with the treatment of cancers with drugs and research on cancer drugs. Although chemotherapy plays a very important role in the treatment of cancers with drugs, it is not the only method. In medical oncology, besides chemotherapy, treatments for cancers are performed with hormone-regulating drugs, targeted drugs and drugs effective on the immune system.
Close cooperation with other specialties such as radiation oncology, surgery, nuclear medicine, radiology, and pathology is required during the applications of medical oncology. In this way, the best results in cancer treatment are obtained through multidisciplinary studies.
The effective doses of the drugs used in oncology and the toxic doses that can be fatal are very close to each other. For this reason, physicians applying the treatment should know the side effects of these drugs very well. A patient with a very good response to treatment may be lost due to therapeutic toxicity. For this reason, physicians, patients and patient relatives should communicate well during the treatment process.
The staging of cancers, the methods of surgical interventions and the types of drugs used change over time. Therefore, physicians dealing with oncology should follow these changes closely. It is now understood that common cancers such as lung, breast and colon cancers have many subgroups, and each one needs to be treated with different methods. For example, the drug called trastuzumab is very effective in both positive breast cancers, while it is useless in both negative breast cancers.
Before starting the treatment of cancers, pathological evaluation with biopsy should be performed and the treatment program (surgery, radiotherapy, chemotherapy, hormone drugs, targeted treatments) should be performed after staging the disease with imaging methods.
Although medical oncology often steps in after the operation (adjuvant applications), it can also start the treatment before the operation (neoadjuvant applications). In advanced stage cancers (breast, colon, lung), the efficiency of surgery can be increased with pre-operative applications. Although there are general principles of oncological applications, it is the best approach to make a patient-specific treatment plan by evaluating the patients together with different specialties at the diagnosis stage.