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Oncologist
Last reviewed: 03.07.2025

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An oncologist is a specialist in the field of diagnostics and therapy of tumor neoplasms. A tumor can be detected in any organ, for this reason, doctors of various specializations are involved in solving the problem of oncology: dermatologists, gynecologists, otolaryngologists, etc.
The medical term oncology comes from the Greek "ónkos" - tumor. Oncology is a science that studies the causes of formation, features of the course and mechanisms of growth of benign or malignant tumors, and also develops ways to prevent the development of pathology and methods of treatment.
In cancer treatment, modern medicine has surgery, chemotherapy, hormonal, immunological and radiation therapy. An oncologist is proficient in one of the listed methods, having knowledge of related healing methods. A consultation is often required to draw up a treatment plan.
Who is an oncologist?
An oncologist is a complex profession. Malignant tumors develop unnoticed, are difficult to treat and are characterized by rapid growth, so the doctor must be a broad-based specialist. It is important to note that each oncologist makes an indispensable contribution to science, sharing their clinical knowledge, experience and discoveries.
These specialists work in oncology centers of hospitals, specialized oncology institutions, and research institutes.
Who is an oncologist? Firstly, a doctor who has knowledge of the symptoms, causes, and specifics of the development of oncological diseases, who has diagnostic methods and treatment and preventive methods. Secondly, an oncologist is a psychologist who can communicate even with dying patients. Therapeutic progress and the possibility of healing largely depend on the doctor's ability to set the patient up for recovery.
Classification of oncologists depending on possible treatment:
- surgical intervention – excision of the neoplasm;
- drug therapy – the use of pharmacological substances (chemotherapy);
- radiation (radiation therapy);
- interventional therapy – minimally invasive therapy using visual control;
- pediatric (diagnosis and treatment of children with cancer).
- gynecological (therapy of tumors of female reproductive organs);
When should you see an oncologist?
The formation of a cancerous tumor at a certain stage is characterized by specific symptoms. List of conditions when you should contact an oncologist:
- detection of bleeding (blood in stool and urine, frequent nosebleeds, bloody discharge from the genital area);
- a sharp decrease in body weight, if the diet and lifestyle remain the same;
- detection of a new growth on the skin, transformation or growth of an existing mole, wart, etc. (change in shape, color, presence of bleeding); •
- a subcutaneous lump can be felt, for example, in the area of the mammary glands;
- growth, inflammation of the lymph nodes;
- chills, fever (lasts for a long time, occurs in attacks, repeats several times);
- a pain syndrome of unknown etiology was detected;
- headache, loss of coordination, hearing and vision disorders;
- unusual discharge from the nipples, impurities and inclusions in the feces;
- frequent, causeless bowel disorders;
- loss of appetite, decreased overall performance and health, nausea without pathology from the gastrointestinal tract;
- a feeling of discomfort over a long period of time – pressure in the chest area, tightness/scratching in the throat, a squeezing sensation in the abdominal and pelvic area.
If the course of treatment for a malignant tumor is over, the oncologist will issue a schedule of preventive visits and routine examinations. This specialist also monitors patients with liver cirrhosis, mastopathy, and intestinal polyposis.
What tests should you take when visiting an oncologist?
When visiting an oncologist, you need to bring the results of previous studies and diagnostics, if any.
What tests should be taken when visiting an oncologist? In order to differentiate the neoplasm, clarify the diagnosis and determine the treatment strategy, the following may be required:
- blood, urine, and excretion studies;
- blood test for tumor markers;
- identification of the degree of sensitivity of cancer cells to the planned therapeutic effect;
- X-ray;
- computed tomography, magnetic resonance imaging;
- Ultrasound examination;
- colonoscopy;
- mammographic examination;
- cytology and biopsy.
The oncologist determines the diagnostic methods individually for each specific case.
What diagnostic methods does an oncologist use?
Diagnostics is the most important stage of oncology, allowing to identify the localization of the tumor formation already during the examination. The history of the disease with characteristic complaints and specific symptoms (sharp weight loss, rapid fatigue, causeless fever or anemia, paraneoplastic pneumonia, etc.) helps to establish the diagnosis.
What diagnostic methods does an oncologist use? To clarify/confirm the doctor's conclusion, the following are used:
- incisional/excisional examination of tissue for the presence of cancer cells (biopsy);
- endoscopic examination of the gastrointestinal tract;
- nasoendoscopy and bronchoscopy;
- X-ray method, ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI);
- nuclear medicine technologies – scintigraphy, positron emission tomography (PET);
- a blood test to detect specific tumor markers that characterize certain types of tumors and are inherent in a number of diseases.
These methods help to resolve the issue of the patient’s operability, i.e. the possibility of complete excision of the tumor focus.
Cytological and histological analysis of tissues allows differentiation of cancer cells.
An oncologist encounters relapses of cancer (metastases, lymph node pathology, etc.) when it is impossible to identify the source tumor. In this case, the principles of empirical therapy are used, based on past experience with the identified root cause.
What does an oncologist do?
An oncologist specializes in the diagnosis and treatment of precancerous and cancerous growths.
So, what does an oncologist do:
- diagnoses any type of neoplasm and establishes a diagnosis;
- has a therapeutic effect through surgical intervention, chemotherapy and radiation therapy, etc.;
- monitors patients after positive results of therapy;
- provides palliative care to patients with terminal cancer;
- is responsible for ethical issues related to oncological diseases;
- detects oncology at an early stage (screening) among risk groups, which include close relatives of cancer patients, as well as in cases of hereditary malignant tumors (for example, breast cancer).
The initial consultation with a specialist includes:
- collecting anamnesis based on patient complaints;
- conducting a visual inspection and palpation;
- referral for specific tests (as indicated – ultrasound, puncture and biopsy, blood test to detect tumor markers, CT scan, mammography, etc.)
It is important to note the ethics of oncological practice. The oncologist must clearly understand:
- what amount of information can be given to a particular patient (including the degree, progression of the disease and expected prognosis);
- involvement in clinical trials, especially of terminally ill patients;
- the possibility of the patient refusing active therapy;
- the patient's unwillingness to be admitted to intensive care, as well as the expression of a desire to end life.
All of these aspects are inextricably linked to personal, cultural, religious and family values. To resolve and smooth out all of the dilemmas, the oncologist must be receptive and have high communication skills.
What diseases does an oncologist treat?
What diseases does an oncologist treat? The specialist deals with the following problems:
- acute leukemia - a disorder of hematopoiesis caused by the spread of immature blast cells of the bone marrow;
- melanoma of the skin – malignancy of pigmented lesions;
- lymphogranulomatosis - the primary cancerous lesion is formed in the lymphatic system and spreads to nearby organs through metastasis;
- myeloma disease - a malignant tumor localized in the bone marrow. Causes destruction of bone tissue, often affecting nearby organs;
- soft tissue sarcoma – cancer of muscle, fat, synovial and other extraskeletal structures;
- neoplasms of a neuroendocrine nature - gastrointestinal tract, kidneys, mammary glands, lungs, etc. Include formations of the gastroenteropancreatic type, carcinoid;
- malignant neoplasms of the mediastinum - location of cancer in the chest area (lungs);
- formations of the central nervous system - tumors grow in the spinal cord/brain, as well as their membranes;
- Uterine myoma is a common benign tumor.
Advice from an oncologist
Malignant tumors are easier to treat in the early stages, so the oncologist's task is to detect the pathology in a timely manner. As is known, it is better to prevent any disease. In the case of tumor cells, this opportunity is provided by preventive examinations, self-examination methods, as well as advice from an oncologist, which extends to:
- Maintaining a normal weight – it has been experimentally proven that cases of obesity increase the risk of cancer;
- physical activity – sports (simple walking) help burn extra calories and have a beneficial effect on overall health;
- reducing fat consumption – overindulgence in fatty foods leads to breast and prostate cancer, as well as colon cancer;
- compliance with the principle of separate nutrition;
- increasing the intake of vegetables, fruits, grains and cereals rich in fiber and vitamins. These products reduce the predisposition to cancer. Fiber speeds up the digestion process, so the existing carcinogens have less contact with the intestinal mucosa;
- moderate consumption of alcoholic beverages (no more than 50 ml per day) – addiction to alcohol threatens cancer of the oral cavity, esophagus, mammary gland and liver;
- restraint in relation to smoked foods – they increase the level of carcinogens;
- avoid foods with nitrates and nitrites (products grown near highways, metallurgical plants, thermal power plants) - in combination with protein foods with appropriate acidity, they produce dangerous carcinogens;
- Quitting smoking – this bad habit causes lung cancer, contributes to gastrointestinal cancer, breast cancer, etc.
If you have alarming, disturbing symptoms, do not waste time worrying and worsening your emotional state. As a highly qualified specialist, an oncologist will dispel your fears or prescribe competent treatment. Remember that cancer diagnosed in time is a curable disease.