The term oncology literally means a branch of science that deals with tumours and cancers. The word “onco” means bulk, mass, or tumor while “-logy” means study.
Each of the cells of the body have a tightly regulated system that controls their growth, maturity, reproduction and eventual death. Cancer begins when cells in a part of the body start to grow out of control. There are many kinds of cancer, but they all start because of out-of-control growth of abnormal cells.
Today, millions of people are living with cancer or have had cancer. Cancer is the second leading cause of death in the Nigeria. About one-half of all men and one-third of all women in the Nigeria will develop cancer during their lifetimes.
Medical professionals who practice oncology are called Cancer specialists or oncologists. These oncologists have several specific roles. They help in diagnosis of the cancer, help in staging the cancer and grading the aggressive nature of the cancer.
The most important diagnostic tool remains the clinical history of the patient. Common symptoms that point towards cancer include fatigue, weight loss, unexplained anemia, fever of unknown origin etc.
Oncology depends on diagnostic tools like biopsy or removal of bits of the tumour tissue and examining it under the microscope. Other diagnostic tools include endoscopy for the gastrointestinal tract, imaging studies like X-rays, CT scanning, MRI scanning, ultrasound and other radiological techniques, Scintigraphy, Single Photon Emission Computed Tomography, Positron emission tomography and nuclear medicine techniques etc.
Common methods include blood tests for biological or tumor markers. Rise of these markers in blood may be indicative of the cancer.
Based on the grade and stage of the cancer, oncologists help plan the therapy that is suitable for each of their patients. This could be by surgery, chemotherapy, radiation therapy and other modalities.
Once initial therapy is completed the oncologists is responsible for follow up of the patient to detect relapse and remission. The former means recurrence or return of the cancer while being in remission means remaining cancer-free.
The oncologist is also responsible for palliative or symptomatic care in patients with terminal malignancies. This and other issues of treatment choice have several ethical issues including patient autonomy and choice that the oncologist needs to be concerned about.
Oncology and cancer research involves screening the general population for cancer and screening the relatives of patients (in types of cancer that are thought to have a hereditary basis. For example, in breast cancer both population screening by regular mammography and familial screening by genetic analysis of the BRCA1 and BRCA2 genes is performed.