Oncology: Your Guide to Understanding Cancer

1. What is Oncology?

The term oncology refers to a branch of science that deals with the treatment of cancer. Oncology is the combination of two terms "onco" and "logy".

Onco means bulk or mass, while logy means study.

We know that abnormal division of cells results in cancerous masses or bulk in the body. So, oncology, by definition, is the study of cancer.

Let me explain it more to help you understand exactly what oncology deals with.

Oncology encompasses the medical discipline that deals with understanding cancer through studying it keenly, preventing cancer, and early detection and treatment of cancer.

2. Oncology: Cancer's signs and symptoms

When we say that oncology is the study of cancer, we mean covering every aspect of it. Diving deep into history to learn the signs and symptoms of cancer is the first and most crucial step. Without performing this step, we cannot move on to another. A doctor and patient must be aware of the signs and symptoms of the disease.

● Excessive night sweats

● Fatigue/ tiredness

● Bruising or bleeding

● Unusual lump or swelling

● A new mole or changes to the previous mole

● Change in skin colour, tone or texture

● More than three weeks of mouth or tongue ulcers

● Cough with bleeding

● Hoarseness of voice

● Appetite loss

● Persistence bloating

● Alteration of bowel habits, such as constipation or loose motion

● Unexpected vaginal bleeding after sex, during menstruation or after menopause

● Unusual changes in breast size, colour, or shape.

If you have any of these signs and symptoms, don't ignore them. Visit the doctor immediately.

3. Oncology: Causes of Cancer

Cancer is a complex disease that involves a variety of contributing factors.

Here are some common causes and risk factors associated with cancer:

3.1. Genetic factors

Some genetic mutations inherited from parents can increase the risk of developing cancer. These mutations can affect the normal functioning of genes involved in cell growth and division.

3.2. Environmental factors

Exposure to certain environmental substances and conditions can increase the risk of cancer. These factors include tobacco smoke, ultraviolet (UV) radiation from the sun, ionising radiation, certain chemicals and pollutants (e.g., asbestos, benzene), and certain infections (e.g., human papillomavirus, hepatitis B and C viruses).

3.3. Lifestyle factors

Some lifestyle changes can contribute to the development of cancer. These include tobacco and alcohol use, an unhealthy diet (low in fruits and vegetables, high in processed foods), a lack of physical activity, and being overweight or obese.

3.4. Age

Cancer risk generally increases with age. This is because when we age, our cells are more susceptible to genetic mutations and other changes that can lead to cancer.

3.5. Family history

Having close relatives (such as parents or siblings) who have had cancer can increase your risk of developing certain types of cancer. It can be due to shared genetic factors or a combination of genetic and environmental factors.

3.6. Hormonal factors

Hormones also contribute to the development of cancer in some cases. For example, oestrogen exposure over a long period of time increases the risk of breast and uterine cancer. Hormone replacement therapy and certain hormonal contraceptives can also influence cancer risk.

3.7. Chronic inflammation

Chronic inflammation, often caused by conditions such as chronic infections or certain autoimmune diseases, can promote the growth of cancer cells.

4. Oncology: Cancer prevention

Cancer prevention involves taking steps to reduce the risk of developing cancer. While it's not always possible to prevent cancer entirely, adopting some lifestyle changes and behaviours can significantly lower the chances of developing the disease.

Here are some approaches for cancer prevention:

● Avoid tobacco. Maintain a healthy weight. Strive for a balanced diet and regular physical activity.

● Eat a healthy diet. Include fruits, vegetables, and whole grains, and limit red/processed meats.

● Stay physically active. Make a plan to exercise 150 minutes daily and strictly follow it

● Protect yourself from the sun. Seek shade, wear protective clothing, and use sunscreen.

● Practice safe sex and get vaccinated. Use condoms and consider HPV vaccination.

● Limit alcohol consumption. Consume alcohol in moderation or avoid it entirely.

● Get regular screenings and vaccinations. Follow the recommended guidelines for cancer screenings and vaccines.

● Avoid exposure to harmful chemicals. Reduce contact with hazardous substances.

5. Types of Oncology

Based on treatment, oncology is classified into different branches for a better understanding of the disease.

Here's a concise overview of the types of oncology:

5.1. Medical Oncology

Focuses on cancer treatment using systemic therapies like chemotherapy, immunotherapy, and targeted therapy.

5.2. Surgical Oncology

Specializes in surgically removing tumors and cancerous tissues through procedures like tumor resections and organ-specific surgeries.

5.3. Radiation Oncology

Use radiation therapy to target and destroy cancer cells while lowering damage to healthy tissues.

5.4. Paediatric Oncology

Deals with the diagnosis and treatment of cancer in children and adolescents, requiring specialized care and treatment approaches.

5.5. Haematology-Oncology

Combines the fields of oncology and haematology, managing blood-related cancers and disorders such as leukaemia and lymphoma.

5.6. Gynecologic Oncology

This branch deals with the diagnosis and treatment of cancers of the female reproductive system, including ovarian, uterine, and cervical cancers.

5.7. Neuro-oncology

Specializes in the treatment of cancers affecting the central nervous system, such as brain tumors and spinal cord tumors.

5.8. Dermatologic Oncology

This branch deals with skin cancer diagnosis and treatment, including melanoma, basal cell carcinoma, and squamous cell carcinoma.

Each type of oncology has its own specific expertise and treatment approaches tailored to the type of cancer being addressed.


6. Who is an Oncologist?

An oncologist is a highly qualified medical practitioner who specializes in cancer and deals with diagnosing, treating, and preventing cancer.

7. Difference between Oncology and Oncologist

Oncology is the discipline of medicine that focuses on cancer prevention, diagnosis, and treatment. It encompasses the study and management of various aspects of cancer, including its causes, biology, staging, treatment options, and supportive care.

On the other hand, an oncologist is a medical doctor who specializes in the field of oncology. They are trained and experienced in diagnosing and treating cancer patients. Oncologists can further specialize in specific areas within oncology, such as medical oncology, surgical oncology, radiation oncology, paediatric oncology, etc.

8. Types of Oncologists

Here's a breakdown of the different types of oncologists:

8.1. Medical Oncologist

Medical oncologists are responsible for developing and implementing treatment plans for cancer patients. They use various systemic treatments such as chemotherapy, targeted therapy, immunotherapy, and hormone therapy to treat cancer.

8.2. Surgical Oncologist

Surgical oncologists specialize in performing surgical procedures to remove tumors and cancerous tissues. They work closely with other specialists to determine the appropriate surgical approach and often play a crucial role in diagnosing and staging cancer.

8.3. Radiation Oncologist

Radiation oncologists focus on treating cancer using radiation therapy. They plan and deliver precise radiation treatments to target and destroy cancer cells while sparing healthy tissues. They collaborate with other oncology specialists to develop comprehensive treatment plans.

8.4. Paediatric Oncologist

Paediatric oncologists specialize in treating cancer in children and adolescents. They have expertise in managing the unique challenges associated with childhood cancers and provide specialized care to young patients and their families.

8.5. Gynecologic Oncologist

Gynecologic oncologists are doctors that specialize in the diagnosis and treatment of cancers of the female reproductive system. They are skilled in performing surgical procedures specific to gynecologic cancers and may also use radiation therapy and chemotherapy to treat these cancers.

8.6. Hematologist-Oncologist

Haematologist-oncologists are trained in both haematology (study of blood disorders) and oncology. They diagnose and treat blood-related cancers, such as leukaemia, lymphoma, and multiple myeloma, as well as other haematological conditions.

9. Oncology: Diagnostic Tools

When we talk about diagnostic tools for oncology, it's obvious that we are talking about the diagnostic methods for cancer.

So, let's have a look at the techniques used for diagnosing cancer.

The first and most vital tool to diagnose any disease is uncovering the signs and symptoms through patient history. Because the first step in diagnosing is a history-taking process through which a doctor asks open-ended and closed-ended questions, then a doctor comes for the physical examination and finally comes to imagining techniques.

(The signs and symptoms of cancer are described in the previous section.)

9.1. Common methods

● Blood tests for biological or tumor markers.

9.2. Imagining techniques

● X-Ray

● CT-Scan

● MRI Scanning

● Ultrasound

9.3. Radiographic techniques:

● Scintigraphy

● Single Photon Emission Computed Tomography

● Positron emission tomography

● Nuclear medicine techniques

10. Oncology: Treatment of cancer

The treatment regimens will be selected based on various factors, such as types of cancer, area of cancer, severity, and stages of cancer.

Here is the most common treatment option for cancer:

10.1. Surgery:

Surgery is the procedure of removing the cancerous part of the body by cutting it down.

10.2. Chemotherapy:

Chemo means chemicals, and therapy means treatment. Through this treatment regimen, doctors treat the patient with medicines that kill the cancer cells that are not visible.

10.3. Radiation therapy:

In this procedure, radiation is used that is similar to X-rays to kill the cancerous cells.

10.4. Hormone therapy:

Through hormone therapy, artificial hormones are introduced into the body to stop cancer cells from getting the hormones they need to grow.

10.5. Immunotherapy:

As we know, the immune system also gets involved in cancer. A weak immune system means a low capacity to fight disease and more chances for disease to grow faster. This treatment option works with the immune system of the body to make it stronger so that it can fight cancer cells and also to lower the complications of cancer treatment.

10.6. Stem cell transplant (bone marrow transplant):

Replace bone marrow cells that have been destroyed by extremely high doses of chemotherapy or radiation therapy. Most commonly, it is used to treat blood malignancies and tumors of the lymph nodes.


Cancer is a life-threatening disease. Early detection of cancer can save your life. Doctors and patients need to have a good knowledge of the disease. By knowing and understanding the disease, there can be better management, prevention, and cure of the cancer. So, oncology strives to accomplish this purpose.

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Disclaimer: The information in this blog article is for educational purposes only and is not intended to be a substitute for professional medical advice. Please consult with a qualified healthcare provider before making any changes to your healthcare regimen.


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Mandal, A. (n.d.). What is Oncology? News Medical. Retrieved July 5, 2023, from https://www.news-medical.net/health/What-is-Oncology.aspx

Signs and symptoms of cancer. (2022, November 17). Cancer Research UK. Retrieved July 5, 2023, from https://www.cancerresearchuk.org/about-cancer/cancer-symptoms