1. What causes cancer?

A. There is no easily definable cause for cancer. It is not caused by normal kinds of viral and  other infections, though a certain type of Stomach cancer is associated with "Helicopylori"  bacteria. It is certainly known today that constant and persistent itching, discomfort or  lesions can become cancerous overtime.

2. How does cancer grow?

A. Cancer is regarded as a disease of cells. It is characterized by an excess of a particular  group of cells, beyond the number needed for normal function of the body organ affected.  Due to the uncontrolled growth of cells, they tend to take away nutrition and growth factors  from other cells to themselves, thus weakening these other cells substantially- to the extent  the body itself is affected. In order to sustain their own growth they can even change the  blood vessels to ensure maximum nutrition availability for themselves. Since the average age  of a cancer cell is much more than that of a normal cell, their population grows at a  phenomenal rate. Their uncontrolled growth blocks the blood passages, food passages,  nerves, etc. and puts enormous pressure on neighboring organs leading to severe pain and  discomfort.

3.What are Carcinogens?

A. Carcinogens are the substances that can cause cancer. These are present everywhere. Air, water and food carry them into our bodies, where they alter the character of the human  cells. Genetic predisposition and intake of carcinogens combine to create a most hazardous  situation for contracting and progression of cancer. Some of the carcinogenic substances are  tobacco, alcohol, heavy metals like Antimony, Cadmium, etc.
 

4.What is Carcinogenesis?

A. Carcinogenesis is the process of the production of the cancerous tendency in the cells; that  is, the process of transforming the normal cells into cancerous cells. It involves the following  steps:

5.Does cancer cause pain?

A. It is a misconception that all cancer causes pain. Just because someone has cancer it does  not mean that one will inevitably have pain. Pain is caused when the tumor becomes large  and exerts pressure on neighboring parts or organs. Not all cancers cause pain, but pain does  accompany some forms of cancers.

6.Is cancer inherited?

A. No, cancer is generally not inherited. There has been no evidence of cancer being inherited  till date. However, there are cases of many cancer patients within a family or over  generations. Since cancer is a disease related to genetics, certain genetic predisposition can  be carried forward from generation to generation in the family, if there is a history of cancer  in a family, prudence demands that the family should get themselves checked and  exercise all necessary restraints.

7. Can viruses cause cancer?

A. Yes, long term existences of some viruses do cause cancer, but there has been very little  evidence available. Particularly, some viruses can cause certain types of cancer. Example, Human T-cell Leukemia (Type of blood cancer), Burkitt's Lymphoma and Nasopharyngeal  Carcinoma, Gastric Carcinoma (stomach cancer).

  
8. What are the types of Cancers?

A. There are many types of cancer as there are many tissues in body. Over 215 types of cancer  have been identified. Typical cancers are brain, blood, bone, lymph, throat, eye, skin  (melanoma), stomach, small intestine, large intestine (intestinal cancer), bowels, liver, ovary  (ovarian cancer), testes(testicular cancer), etc. The most common sites of cancer in the  body are lung, breast, cervix, bowels, throats, stomach, ovary, etc. Classification of type of  cancer, is done based upon the tissues & organs in a body in which it is originated. On this  basis, cancer can be  divided into Carcinoma, Sarcoma and Leukemia.

9.What is Carcinoma?

A. Carcinoma is the cancerous change in the tissues that line the body organs that is epithelial  cells. For example, Breast cancers.

10.What is Sarcoma?

A. Sarcomas are the cancers that arise in the connective tissues like nerve, muscle, and bone.  For example. Brain tumours.

11. What is Leukemia?

A. The cancer of blood cells and the cells of the immune system which are found in lymphnodes  is referred to as Leukemia.

12. What is Metastasis?

A. The last stage of cancer process is "Progression". It involves increased growth and expansion  of a population of initiated and promoted cancer cells from a localised spot that is a focal  lesion to an invasive tumour mass, accompanied by an increasingly abnormal complement of  the genetic material. DNA damage is wide spread with loss, breakage and duplication of the  multiple chromosomes. This leads to migration of these cells to distant sites in the body  causing spread to other areas. This is called as Metastasis.

13. Can certain types of food cause cancer?

A. Yes, certain foods can definitely cause cancer. In crops such as maize, which are stored  under unsatisfactory conditions, certain moulds produce chemical substances called " Aflatoxins", which directly lead to liver cancer.

14. What is the cause of cancer at the cellular level?

A. As cancer arises from a single cell, once the abnormal behaviour of cell starts, the capability  of such behaviour is handed over to the daughter cells and the process continues. This  sudden trigger in the cell behaviour is responsible for cancerous activity at the cellular level.  This change in behaviour is called as conversion from benign condition to malignancy.

  
15. Can psychological factors cause cancer?

A. Greek philosopher and physician Galen suggested that "melancholy" women are more  susceptible to breast cancer. Psychologists have assessed certain groups of cancer patients,  where they claim that psychological factors have a bearing on the development of cancer.  The basic cause of cancer is the defective immune system, its failure to detect and eliminate  the abnormal cells. The immune system does not work on its own, in isolation. It can be influenced by the central nervous system and the endocrine system (responsible for the  hormonal secretions). If the person is psychologically affected, it affects the hormonal status of the body also and hence the immune system becomes functionally depressed.

 For example, bowel cancer affects many people suffering from Ulcerative colitis later. The probable reason here may be the psychological factors because Ulcerative colitis itself leads  to psychological depression.

 Hence, we can say that though psychological factors may not directly cause cancer, they  play a vital supporting role.

16. Does Polymeric packaging material cause cancer?

A. Many foods and drinks contain traces of chemicals used in packaging. Migration of these  food materials that are in contact materials can occur during processing, storage and  preparation of food. The polymeric materials used for packaging are inert, but their  monomers like vinyl chloride and acrylonitrile migrate into foods and have mutagenic or  carcinogenic effects. Traces of these heavy metals are left in the packages, which  migrate into human body through food,  water, etc and can cause cancer.

17. Can water cause cancer?

A. Water supplies may contain chlorine, fluoride and nitrates as residues. Till date the  epidemological evidence on the consequences of exposure to residue of water borne chlorine  and flouride is limited. N-nitroso compounds formed in the body after consumption of nitrates  as water residue increase the risk of Stomach cancer. Certain heavy metals and Arsenic even  in low levels, tend to accumalate in human body and cause cancer. Hence, drinking water  and water used for cooking should be pure.

18. How does the use of Tobacco attribute to the risk of cancer?

A. Tobacco is the chief cause of lung cancer. It is probably the most important single cause of  cancers of the upper digestive tract which includes mouth, tongue, throat, eosophagus, etc.  Drinkers who also smoke have increased risk of these cancers. It also contributes to the  cancer of the bladder, pancreas and cervix. Since oxygen intake gets greatly reduced in case  of smokers, the tendency of the genes to get mutated becomes high, which over time become malignant or cancerous.

  
19. What is the link between food preservation and cancer risk?

A. Studies have provided convincing evidence that refrigeration decreases the risk of stomach  cancer, by reducing the need for salt as a preservative and enabling year round availability of  vegetables and fruits. On the other hand, refrigerated material kept for too long, increases  the risk of exposure of digestive tract to bacteria and viruses, thus increasing the risk of  related diseases.

20.What are Biomarkers?

A. Analysis of the biological materials such as plasma, DNA, etc help to improve the  understanding of the relation between food, nutrition and cancer. Biomarkers are biological  indices, which are used to improve measurement of susceptibility to cancer, precancerous  conditions and cancer progression. In cancer patients, their level indicates the seriousness  and extent of resurgence of cancer.
 
 
21. How can cancer be prevented?

A. The most important steps for cancer prevention are:

22. What are the Dietary Guidelines for cancer patients?

A. The dietary guidelines mentioned by the American Cancer Society are: