Fri, 12 July 2019 2:56
WHAT IS CANCER?
Cancer in a broader sense is a disease that occurs when cellular changes cause uncontrolled growth and division of cells. Each cell in the body has a specific function and fixed lifespan, and cell death is a natural and beneficial phenomenon called apoptosis. A cell receives instructions to die so that the body can replace it with a new cell. However, cancer cells lack the components that instruct them to stop dividing and die.
Cancer cell forms tumours, damage the immune system, and hinders the proper functioning of the body. Cancer cells appear in one area and then they spread through nymph nodes, these are clusters of immune cells located throughout the body, such as neck, groin and underarms area. Some types of cancer cells grow and divide at a slower rate. Cancer can also spread through the bloodstream to different parts of the body, these parts may include liver, lungs, brain, and bones.
Genetic factors also contribute to the development of cancer. Certain genetic changes occur after birth and factors such as sun exposer and smoking can increase the risk. Change in the genes can lead to faulty instructions and can further result into cancer. Inherit genetic mutations significantly contribute to the development of 5–10% of cancer cases.
There are two types of cancer genes:
- Anti-cancer genes whose cancer-inducing effect is due to the termination of their cells activity.
- Oncogenes are cancer generating genes whose activation causes an uncontrollable distribution of cell tissues.
Main Types of Cancer
Cancer is further classified into sarcoma, carcinoma, leukaemia and lymphocytic.
Sarcoma is a type of tumor that affects connective tissues. Soft tissue sarcoma affects muscle, fat, blood, vessels, deep skin tissues, cartilage, tendons, and ligaments. Soft tissues sarcoma are tumours that affect the tissues that connect and support the body systems, it mainly affects bone, skin and other soft tissues. It is a rare type of cancer, however, 14000 cases of soft tissue sarcoma are diagnosed annually in the U.S.
- Gastrointestinal stromal tumour - These affect specialized neuromuscular cells of the gut.
- Liposarcoma- It is a sarcoma of the fat tissues.
- Leiomyoma-sarcoma – This affects the smooth muscles in organ walls.
- Synovial sarcoma – These are found around the joints in the arms or legs.
- Angiosarcoma – These develop in the blood cell or lymph vessel.
- Pleomorphic sarcoma – This tumour is found in the arms, legs or at the back of the abdomen.
- Rhabdomy-sarcoma – These forms in the muscle and is a type of tumour commonly found in children.
The following are the symptoms of sarcoma:
- Blood in the stool or in vomit.
- Abdominal pain that gets worse
- Black stools
- Growth of new lumps on the body
Carcinoma occurs in the epithelial tissue of the skin or in the tissues that lines internal organs, such as liver or kidney. It might spread to the other parts of the body or be confined to the primary location. Carcinoma is the most common type of cancer, the disease has various forms which include;
- Invasive ductal carcinoma- This occurs when cancer cells grow in the duct lining, beak though the wall and then invade the breast tissue. From there, it may spread to other body parts.
- Squamous cell carcinoma – This is the second most common type of skin cancer. Squamous cell cancer has a slow growth rate and it is uncommon for them to spread.
- Basal cell carcinoma – It is one of the most common type of skin cancer. Here, cancer cells develop in the basal cell layer of the skin. Basal cell cancer usually grows slowly and they rarely spread.
- Renal cell carcinoma – This is the one of the most common type of kidney cancer. The cancer cells develop in the lining of kidney tubes, called tubules. It can form in one or both kidneys.
- Ductal carcinoma in situ – It is the most common type of breast cancer. The cancer cells develop into the lining of the milk ducts and then spreads to the breast tissue.
- Blood in the urine
- Persistent lumps or swollen glands
- Unexpected weight loss, fever or night sweats
Leukaemia is a cancer of the blood or bone marrow. It occurs when there is a problem with the production of white blood cells. It mainly affects the people over the age of 55 years, however, it can also occur in those aged under 15 years. In the U.S. around 62130 people are diagnosed with leukaemia and around 24500 people die due to this disease.
- Acute and Chronic leukaemia – In acute leukaemia the immature cells develop rapidly and collect in the bone marrow or in blood. It develops fast and gets worse rapidly. Whereas, chronic leukaemia progresses slowly and gets worse over time.
- Lymphocytic leukaemia – This occurs if the cancer cell changes and affects the type of bone marrow that makes lymphocytes. It is a kind of white blood cell that plays a role in the immune system. Acute Lymphocytic leukaemia is the most common type of leukaemia among young children and in adults, it occurs after the age of 65. Chronic Lymphocytic Leukaemia is most common in people over the age of 55, and more detrimental to men than women.
- Myelogenous Leukaemia – It happens when the cell change affects the type of bone marrow cells that produces white blood cells, red blood cells, and platelets. Acute Myelogenous leukaemia is more common in adults than in children. Chronic myeloid leukaemia is caused by a spontaneous mutation of chromosome cells.
- Blood clotting
- Frequent infections
- Bone pain
It is a type of cancer that affects the Lymphatic system. It damages a type of white blood cells known as lymphocytes that helps fight diseases in the body. Lymphoma can occur at any age, but it is more common in children and young adults aged 15 to 24 years.
- Non-Hodgkin – It is the most common type, and affects mainly B and T cells. It accounts for 90% of lymphoma cases and around 4% of all cancers in the U.S.
- Fever without infection
- Weight loss and loss of appetite
- Unusual itching
- Fatigue, tiredness and lack of energy
- Pain in nymph nodes.
- Persistent coughing
- Shortness of breath
Cancer treatments are constantly developing and as a result of that, the outcomes have improved. Some of the treatment types are Adjuvant therapy, combination therapy, supportive therapy, and palliative therapy.