Introduction to Oncology

Cancer: Cancer is uncontrolled abnormal growth of cells which results in the formation of tumors causing multiple disease symptoms and destruction of body tissue. It weakens the immune system and has the capability to spread across the body. It is one of the leading causes of the death worldwide but recent advancements in its screening, treatment and surgery has been able to control it significantly. Most Common Types of Cancer:   Cancer is generally divided into four categories:-

• Carcinomas– affects the skin or the tissue covering the surface of internal organs and glands.
• Sarcomas– affects the supporting or connective tissues of the body.
• Leukemias– often referred as cancer of blood or blood cancer.
• Lymphomas– cancer of the lymph nodes or lymphatic system.

  Most common cancer forms:

• Breast Cancer
• Prostate Cancer
• Basal Cell Cancer
• Melanoma
• Lung Cancer
• Colon Cancer
• Thyroid Cancer
• Head & Neck Cancer
• Brain Cancer
• Liver Cancer
• Stomach Cancer
• Kidney Cancer
• Bladder Cancer

Symptoms leading to Cancer: Signs and symptoms depends on the body parts affected, some common symptoms are as follows: – Fatigue or lack of energy and enthusiasm – Lump formation under the skin leading to solidification or thickening of cells. – Feeling of breathlessness and persistent coughing. – Weight Changes either loss or gain of weight – Skin changes such as redness, darkness of skin, unhealed sores, etc. – Uneasy bowel movements or changes in bladder habits. – Unexplained bleeding, bruising, yellowing of skin – Muscle and joint pain, hoarseness, difficulty in swallowing. Causes of Cancer: Cancer is caused by mutations or changes in DNA within cells. The coded genetic signals carried to DNA gets affected by the external factors causing uncontrolled growth of cells leading to the formation of malign tumors resulting in causing cancer. Generally the external agents whose interaction affects an individual genetic function are:

• Physical Carcinogens- ultraviolet and ionizing radiations
• Chemical Carcinogens- Free radicals and components of tobacco, cigarettes, smoke , asbestos, alcohol, alfa-toxins, arsenic (water contaminent); and
• Biological Carcinogens- this includes parasites, bacterial, and viral infections.

  Risk Factors: *Exposure to free radicals and carcinogens *Excessive Alcohol *Obesity *Poor Diet *Lethargic lifestyle or lack of physical activity *Age *Particular type of infections