Health Desk
Sandeep Dhand Ludhiana
Journalist and Research Analysist
Oncology is the branch of medicine that focuses on the diagnosis, treatment, and prevention of cancer. Cancer, characterized by uncontrolled cell growth, can affect nearly every organ and tissue in the body. Oncologists, the specialists in this field, play a crucial role in managing cancer patients through various stages of treatment, from initial diagnosis to ongoing care and, in many cases, long-term remission or palliative care.
Types of Oncology
There are three primary branches within oncology, each dedicated to a specific aspect of cancer care:
- Medical Oncology: This branch involves the use of chemotherapy, immunotherapy, targeted therapy, and hormonal therapy to treat cancer. Medical oncologists often serve as the primary healthcare provider for patients with cancer, coordinating care with other specialists and overseeing systemic treatments.
- Surgical Oncology: Surgical oncologists focus on the surgical removal of tumors and cancerous tissues. This branch of oncology is critical in the diagnosis (through biopsy), staging, and treatment of solid tumors. Surgery can be curative, palliative, or used to debulk tumors before other treatments like chemotherapy or radiation.
- Radiation Oncology: This field utilizes high-energy radiation to target and destroy cancer cells. Radiation therapy can be used as a standalone treatment or in combination with surgery and chemotherapy. Radiation oncologists specialize in delivering precise doses of radiation to affected areas while minimizing damage to healthy tissue.
Additionally, other subfields within oncology include:
Pediatric Oncology: Deals specifically with cancers in children.
Gynecologic Oncology: Focuses on cancers of the female reproductive system.
Hematologic Oncology: Treats cancers of the blood, such as leukemia, lymphoma, and multiple myeloma.
Causes and Risk Factors of Cancer
Cancer occurs when there are genetic mutations that disrupt the normal cell cycle, leading to uncontrolled cell growth. These mutations can be inherited, but most are acquired due to external factors. The exact causes of cancer vary by type, but common risk factors include:
Genetic predisposition: Some people inherit mutations in genes like BRCA1 and BRCA2, increasing their risk for cancers like breast and ovarian cancer.
Lifestyle factors: Smoking, excessive alcohol consumption, poor diet, and lack of physical activity are major risk factors for cancers like lung, liver, and colorectal cancers.
Environmental exposure: Prolonged exposure to carcinogens such as asbestos, certain chemicals, and radiation can increase the risk of developing cancer.
Infections: Certain viruses, like human papillomavirus (HPV) and hepatitis B or C, can cause cancers such as cervical and liver cancers, respectively.
Age: The risk of cancer increases with age, as DNA damage accumulates over time.
Diagnosis of Cancer
Diagnosing cancer involves several steps and tests to confirm its presence, determine its type, and assess how far it has spread (staging). Common diagnostic methods include:
- Biopsy: The removal of a small tissue sample from the suspected tumor for examination under a microscope is the most definitive method to confirm a cancer diagnosis.
- Imaging: Techniques like X-rays, CT scans, MRI, ultrasound, and PET scans help visualize the tumor’s location, size, and spread.
- Blood Tests: These tests can detect cancer markers, such as PSA for prostate cancer, or abnormal levels of certain substances that may indicate cancer.
- Genetic Testing: Helps in identifying inherited mutations that might increase cancer risk or predict how well certain treatments will work.
Staging and Grading of Cancer
Once cancer is diagnosed, it’s important to determine how advanced it is. The stage of cancer refers to its size and whether it has spread to nearby tissues or other parts of the body. Staging helps guide treatment decisions and estimate the prognosis. The most commonly used staging system is the TNM system:
T stands for the size of the primary tumor.
N refers to whether cancer has spread to nearby lymph nodes.
M indicates whether there is metastasis (spread to distant organs).
Cancers are also graded based on how abnormal the cancer cells look under a microscope. Higher grades typically suggest a more aggressive cancer that is likely to grow and spread more quickly.
Treatment of Cancer
Cancer treatment is often multimodal, meaning a combination of therapies is used. The choice of treatment depends on the type, stage, and grade of cancer, as well as the patient’s overall health.
- Surgery: Surgical removal of the tumor is common, especially in early-stage cancers. In some cases, surgery is the only treatment required.
- Chemotherapy: The use of drugs to kill cancer cells or stop them from growing. Chemotherapy can be systemic, affecting the entire body, or targeted, affecting only specific areas.
- Radiation Therapy: Uses high-energy rays or particles to destroy cancer cells. It is often used in combination with surgery or chemotherapy.
- Immunotherapy: This treatment boosts the body’s immune system to better fight cancer. It has shown great success in certain cancers like melanoma and lung cancer.
- Targeted Therapy: This involves drugs that specifically target cancer cells without affecting normal cells. These therapies block the growth and spread of cancer by interfering with specific molecules involved in tumor growth.
- Hormonal Therapy: Used in cancers that are hormone-sensitive, like breast and prostate cancer. This therapy blocks or lowers the amount of hormones in the body to slow or stop the growth of cancer.
Advances in Oncology
In recent years, oncology has seen significant advancements. Some key areas of progress include:
Precision Medicine: Tailoring treatment based on the individual genetic makeup of a patient’s cancer. This allows for more targeted therapies that are often more effective and have fewer side effects.
Immunotherapy: Breakthroughs in immunotherapy have transformed cancer care, especially with checkpoint inhibitors, which release the immune system’s brakes, enabling it to attack cancer cells more effectively.
CAR-T Cell Therapy: A type of immunotherapy where a patient’s T-cells are genetically engineered to attack cancer cells.
Artificial Intelligence (AI): AI is increasingly used in oncology for improving diagnosis accuracy, predicting outcomes, and personalizing treatment plans.
The Role of Oncologists and Multidisciplinary Care
Oncologists work within a multidisciplinary team, including surgeons, radiologists, pathologists, and nurses, to provide comprehensive care. They guide patients through complex treatment decisions, offer emotional and psychological support, and ensure that all aspects of cancer care are addressed.
Conclusion
Oncology is a rapidly evolving field, offering hope to millions of cancer patients around the world. Advances in research, treatment, and early detection are improving survival rates and quality of life. However, much work remains to be done in understanding the full complexity of cancer and developing even more effective treatments. For patients, early diagnosis, access to multidisciplinary care, and staying informed about new treatment options are key to successful cancer management.