· Serious non-communicable disease characterized by abnormal and uncontrolled growth of organs due to rapid multiplication of cells in which controlling and regulating mechanisms have been lost.
· These cells also lose their attachment to other cells and move apart around irregularly more or less like the legs emerging out from the main body of the crab so it is called cancer.
· The uncontrolled growth of cells of cancerous tissue is called neoplasm.
· The uncontrolled growth of cells of cancerous tissue is called neoplasm.
· Tumour is an abnormal swelling, lump or mass in the body.
· The study of tumour or cancer: Oncology
· The study of tumour or cancer: Oncology
· Carcinology is the study of Crustaceans (Arthropods), not of cancer.
· The medical professional who practices oncology: Oncologist
· Breast, gastric, prostate and uterine cancers are the most common cancers in Nepal.
· The medical professional who practices oncology: Oncologist
· Breast, gastric, prostate and uterine cancers are the most common cancers in Nepal.
· Tumour: Group of undifferentiated cells which grow and disorganize the tissues in which it occurs.
· It is of two types: Benign and Malignant tumour.
· The differences between benign and malignant tumours are given below:
| Benign tumour | Malignant tumour |
|---|---|
| Non-cancerous and is less harmful than malignant tumours. | Cancerous more harmful and life-threatening |
| It is only confined to its place of origin (enclosed in connective tissues). | It is not only confined to its place of origin but also spreads into the other body parts through the bloodstream and lymph vessels |
| No metastasis. | Metastasis occurs |
| It is slow-growing | It is fast-growing. |
| Reoccurrence is rare. They can be removed easily with fewer chances of reoccurrence. | Reoccurrence is common. They are difficult to remove as they need chemotherapy, radiation therapy for treatment with more chances of reoccurrence. |
| Never forms a secondary malignant tumour | They form secondary malignant tumours. |
· Metastasis is the spreading of cancerous cells from one part of the body to another through blood, lymph and secondary form of the malignant tumour.
· The cells in benign tumours manufacture chemicals (adhesion molecules) that cause them to stick together. Malignant tumour cells do not produce these molecules and can break off and “float away” to other regions of the body resulting in metastasis.
Types of Cancer
· Based on the type of tissue affected, Classified into 3 types: carcinoma, sarcoma, and fluid cancer.
i) Carcinoma: (Gr. karkinos – Crab, oma- tumour):
· Malignant growth of epithelial (ectodermal) tissues and their derivatives.
· Examples: Breast cancer, Lung cancer, Skin cancer, Brain tumour, Prostate cancer etc.
· The cure of carcinoma cancer depends upon what stage it is in.
· About 85% of all cancer is carcinomas.
ii) Sarcoma:
· Malignant tumour of mesodermal tissues like muscles, Fibrous tissue (Fibrosarcoma), Adipose tissue (Liposarcoma), Bone (Osteosarcoma), Cartilage (Chondrosarcoma), blood and lymph.
· Only 1% of cancers are sarcomas in humans.
iii) Fluid cancer
a. Leukemia:
· It is the malignant growth of leucocytes (WBC).
· The person affected by this cancer shows the excessive production of WBC, which is also called blood cancer.
· It may lead to Splenomegaly (enlargement of the spleen), Hepatomegaly (enlargement of the liver).
b. Lymphoma:
· Malignant tumour of reticuloendothelial tissues (Liver, spleen, bone marrow and lymph nodes).
Occurrence:
· Cosmopolitan fatal disease after the AIDS
· Reported since ancient times, Breast cancer was reported by Hippocrates in the 17th century.
· The incidence of cancer increases with age.
· About 2 million people die per year in the world due to cancer.
Causative Agents
· Carcinogens (Factors or physical or chemical agents that induce cancer growth like Nicotine, Caffeine, Arsenic, Asbestos, Cadmium oxide, Coal products, Benzene, Naphthalene etc.
· Radioactive exposure like ultraviolet rays, x-rays, alpha rays, solar radiation.
· Red meat, a diet with maximum fat- colon cancer
· Excessive alcoholism may cause liver cancer.
· Long time unhealed wounds may also transform into cancer.
· Oncogene: It is a gene that sustains some genetic damage and therefore produces a protein capable of cellular transformation.
· The genes that may cause normal cells to cancerous are known as oncogenes. Our body cells normal genes called proto-oncogene that functions normally for the growth and development but due to the mutation or increased expression produces oncoprotein capable of cellular transformation which results in a cancer-causing oncogene.
· Onchoviruses: Viruses that cause cancer like:
i. Hepatitis B and C Viruses are related to hepatocellular carcinoma.
ii. Cytomegalovirus (CMV) causes Kaposi’s sarcoma.
iii. Human Papilloma Virus (HPV) is the chief suspect of cervix cancer.
Symptoms
· As per American Cancer Society, CAUTION- To recognize early signs of cancer
· C- Change in bowel or bladder habits
· A- A sore or wound that does not heal for a long time.
· U- Unusual and non-injury bleeding
· T- Thickening or lump in the breast or other body parts
· I- Indigestion persistent, difficulty in swallowing
· O- Obvious change in shape, size, colour or thickness of a wart, mole
· N- Nagging cough or hoarseness
Other symptoms
· Persistent fatigue, nausea, vomiting
· Chest pain, shortness of breathe
· Unexpected loss of appetite or loss of body weight
· Persistent low-grade fever
Diagnosis
· The cancer is diagnosed on the basis of certain pathological examinations like:
i. Biopsy (a technique in which a very small part of fluid or tissue sample is taken out from the body for examination.)
· In some instances, the surgery to diagnose cancer may result in a cure if all of the cancerous tissue is removed at the time of biopsy.
ii. Endoscopy, x-rays, Ultrasound, Pap smear test (for Cervix and Genital Tract Cancer)
iii. CT scan (Computed Tomography), MRI Scan (Magnetic Resonance Imaging), PET (Positron Emission Tomography)
Treatment
· Treatment of cancer is based on its nature.
· It can be treated in three ways-surgery, radiotherapy and chemotherapy.
· Surgery:
· Removal of affected parts or tumours before metastasis.
· It is especially applied for breast cancer, colon cancer, lung cancer, uterus cancer and some brain tumours
· Radiotherapy:
· Use of different radioactive rays and is generally used for bladder, cervix, and throat cancer.
· The infected part is exposed to radiation from UV- rays, X- rays, Cobalt 60, Iridium and Iodine, Gold 198, Gallium.
· These rays must be concentrated on the affected parts only because they can destroy other normal cells too.
· Chemotherapy:
· Use of Certain anticancer chemicals and drugs which stop the growth of cancer cells or kill them are administered.
· It is effective against leukaemia and lymphomas.
· Chemicals like Interpheron, Carboplatin, Cisplatin
· Anticarcinogenic chemicals- Actinomycin, Mythramycin
· Vitamin E (Tocopherol) for the early stage of the thickening of the breast
· Recently reported anticancer drugs are Taxol and Taxol Taxotere.
· Testosterone for breast cancer
· Immunotherapy is a form of treatment that enhances the body’s ability to recognize cancer cells and destroy them. It can be given intravenously or by subcutaneous injection.
· Anticarcinogens occur in green-yellow vegetables, fruits and milk. They are riboflavin (milk), flavonoids (green-yellow vegetables and fruits), vitamin C, Indoles (Cabbage and cauliflower), Retinoids (milk, Carrot, Butter), some synthetic oxidants in preserved foods (Example: Butylated hydroxyanisole toluene), etc. B-carotene present in green-yellow vegetables is a promoter-inhibitor that weakens the action of cancer promoters.
Preventive measures
1. Try to avoid and protect from carcinogens
2. Avoid alcoholism and tobacco consumption
3. Refuse X-rays except when absolutely necessary.
4. Ensure proper personal hygiene, simple food habits and ways of life as far as possible.
5. Minimize the exposure to environmental causes of cancer.
6. Join, form or support a group whose primary objective is to put pressure on government and industry to stop the poisoning of our food, air and water with cancer-causing agents.
7. Health education regarding early diagnosis and treatment of the disease
8. Persons of old age should be encouraged and motivated for regular periodic medical check-ups.
9. Provision for aftercare and rehabilitation of cancerous patients should be kept in view.
· Theme of world cancer day 2012 “TOGETHER IT IS POSSIBLE”
· February 4- World cancer day
· November 7- National Cancer Awareness Day
Also, Read our other Notes related to HUMAN DISEASES: