Oncology is a branch of medicine that deals with cancer. A medical professional who practices oncology is an oncologist. Oncology is concerned with: The most important diagnostic tool remains the medical history: the character of the complaints and any specific symptoms (fatigue, weight loss, unexplained anemia, fever of unknown origin, paraneoplastic phenomena and other signs). Often a physical examination will reveal the location of a malignancy. Diagnostic methods include: Apart from in diagnosis, these modalities (especially imaging by CT scanning) are often used to determine operability, i.e. whether it is surgically possible to remove a tumor in its entirety. Generally, a "tissue diagnosis" (from a biopsy) is considered essential for the proper identification of cancer. When this is not possible, "empirical therapy" (without an exact diagnosis) may be given, based on the available evidence (e.g. history, x-rays and scans.
Contributions by Jfdwolff, Jellytussle, and Versageek.