Causes of Cancer | What Causes Cancer | Cancer Causes

Cancer

Cancer is a group of diseases characterised by out-of-control cell growth. There are more than 100 different types of cancer. The cancer is named after the area of the body or organ where it originates.

Submitted by Dr S. Patel on 15 October 2015

What causes cancer?

Understanding the causes and risk factors can help in cancer prevention efforts and early detection strategies. Here are some common triggers:

Genetics - Genetic predisposition can increase the risk of certain cancers, especially in families with a history of the disease. Each cell in our body contains DNA, which controls its action. Any change or mutation to the DNA that damages the genes involved in cell division can lead to cancer. Cancer occurs when because of gene mutation, the cell is unable to correct DNA damage and unable to die.
Carcinogens: Carcinogens are cancer-causing substances that cause damage to the DNA of the cell. All forms of tobacco, natural or man-made radiation, asbestos, certain food and food additives are some of the carcinogens. The following foods and cooking methods have also been linked to cancer: barbecuing or grilling meat; charring and deep frying food; acrylamide in french fries and potato chips; microwave popcorn; artificial sweeteners and sodas; processed meat and fatty red meat; highly processed foods which are low in fiber.
Diet: Poor diet high in processed foods, red meat, and low in fruits, vegetables, and fiber may increase cancer risk.
Obesity: Being overweight or obese is linked to a higher risk of developing various cancers, including breast, colon, and prostate cancer.
Tobacco consumption: Chewing tobacco and smokeless tobacco contain carcinogens such as nitrosamines and nicotine, and both can cause cancer. Chewing tobacco increases the risk of mouth, throat, oesophagus, and pancreatic cancer, whereas smokeless tobacco can cause mouth, tongue, cheek, and lip cancer.
Alcohol Consumption: Excessive alcohol consumption increases the risk of cancers of the mouth, throat, oesophagus, liver, colon, and breast.
UV Radiation: Exposure to ultraviolet (UV) radiation from the sun or tanning beds increases the risk of skin cancer.
Pollution: Carcinogens in air, water, and soil, such as asbestos, benzene, and arsenic, can contribute to cancer development.
Occupational Exposures: Some occupations involving exposure to chemicals, radiation, or asbestos fibers increase the risk of cancer, such as asbestos-related mesothelioma and radiation-induced cancers among factory and plant workers.
Heredity: Cancer can be caused by genetic predisposition that is inherited from family members. Childhood retinoblastoma is the most striking example of the role of heredity.
Hormonal factors: Long-term use of hormone replacement therapy in postmenopausal women has been associated with an increased risk of breast and ovarian cancers.
Immune system: People who have a problem with their immune system are more likely to get some types of cancer. i.e., people who have had organ transplant and taken drugs to suppress their immune system.
Viruses: Some viruses are known to cause cancer. HIV (Human Immunodeficiency Virus) weakens the immune system and increase the risk of Kaposi’s sarcoma, Non-Hodgkin lymphoma, Hodgkin lymphoma, anal cancer, and cervical cancer.
Certain cancers and viruses have been linked with each other.
- Kaposi’s sarcoma due to human herpes virus
- Cervical cancer due to human papilloma virus
- Primary liver cancer due to hepatitis B and C virus
- Lymphomas from Epstein-Barr virus

Risk factors for cancer

People of all ages can get cancer but the frequency of cancer increases with age. As people age, there are more cancer causing mutations in cell DNA.
Heredity and family history of cancer
Diet and lifestyle: Smoking, alcohol and consumption of more processed foods
Spending long hours in the sun or have workplace hazards like chemicals or radiation
Obesity is linked to increased risk in 13 different cancers as per various studies conducted.
1. Adenocarcinoma of Oesophagus
2. Breast Cancer in post-menopausal women
3. Colorectal Cancer
4. Gallbladder cancer
5. Gastric Cancer
6. Kidney Cancer
7. Liver Cancer
8. Meningioma - a usually benign brain tumour
9. Multiple Myeloma, a blood cancer
10. Ovarian Cancer
11. Pancreatic Cancer
12. Thyroid Cancer
13. Uterine Cancer

Learn cancer terms: https://www.patientsengage.com/conditions/cancer-terms-explained

Community

Cancer

Condition

Cancer

Stories

Foods that increase Cancer risk

1. Processed and Red Meat: contribute to colorectal cancer, the most common cancer in Singapore and one of the top 5 cancers in India as well as to stomach, breast, endometrium, oesophagus cancer. Regular consumption, even in small quantities increase your risk because of presence of nitrates and nitrites. 2. Cured and Salted Fish: Preserved fish are high in nitrates and nitrites and increase the risk of nasopharyngeal cancer. Opt for oily fish like salmon, sardines and tuna which are…
Student aces A-level exams despite cancer

He was diagnosed with colon cancer in his first year of junior college, which kept him away from school for four months. But that did not stop Hwa Chong Institution student Ng Yi Pin from catching up with his studies. He also managed to find the time and energy to tutor his older twin brother, Yi Yang, who studied in the same school. Yesterday, the 18-year-old scored eight As for his A levels. Yi Yang also made a marked improvement from his usual results. Yi Pin was in Secondary 4 when he…
Immunotherapy: Arming the immune system against cancer

Instead of poisoning a tumuor or destroying it with radiation, Dr. James P. Allison, chairman of the Immunology Department at the University of Texas, M.D Anderson Cancer Centre, Houston has pioneered ways to unleash the immune system to destroy a cancer He proposed to develop drugs that unleashed the T-Cells. T-Cells of the immune system which are attack cells, latch onto the cells infected with viruses and bacteria and ultimately kill them. The first drug developed was Yervoy against…
Basket Studies - Faster way to try drugs on cancers

Chemotherapy and radiation failed to work on Erika Hurwitz's rare cancer of white blood cells. So her doctors offered her another option - a drug for melanoma. Within 4 weeks, her cancer was undetectable. Mrs. Hurwitz is part of a new national effort in the United States to try and beat cancer basednot on what organ it startedin, but on what mutations drive its growth. There are now an increasing number of drugs that block mutations in cancer genes and can halt a tumour's growth. The…
Colon cancer at 27 did not stop her aiming for 5Km

Choo Mei Sze from Kuala Lumpur, Malaysia surprised doctors with her condition and then even more with her fighting spirit. The TV host/columnist/blogger/emcee shares her tips for coming back stronger than ever. Please tell us a bit about your condition. I had stage 1b/2 colon cancer. The tumour was 1/3 the size of my colon and I had to remove 2/3 of my rectum and 12 cm of my colon, total of 18 lymph nodes. I had complications during the surgery as I had low blood…
Oliver Sacks on learning he has terminal cancer

Oliver Sacks, professor of neurology at the New York University of Medicine. He had an ocular melanoma (a rare tumor of the eye), the treatment of which with lasers and radiations left him blind in that eye. On discovering that he had multiple metastases in the liver, he wrote this lovely piece. "It is up to me now to choose how to live out the months that remain to me. I have to live in the richest, deepest, most productive way I can" "Above all, I have been a sentient being, a thinking…
A significant number of cancer patients are treated by non-specialists

On the occasion of World Cancer Day, Dr V Shanta, Chairperson of Adyar Cancer Institute, Chennai, a doyenne in her field, talks to PatientsEngage about the challenges of tackling cancer in India. “India has state of the art facilities but it does not reach everyone.” PE: There are many differing views on how frequently one should have mammograms. You have said that annual mammograms are unnecessary. Dr. Shanta: I believe that we do follow the general guidelines laid…
The Jonathan Dimbleby doctrine: You don’t beat cancer by not talking about it

Broadcaster Jonathan Dimbleby – son of a BBC legend – tells Charlie Cooper how his father’s candour informed the family’s attitude to coping with illness Britain in 1965 was not a country that talked about cancer. So when one of the most recognisable men in Britain, the veteran broadcaster Richard Dimbleby, decided in October 1965 to go public with the fact that he was suffering from it, the announcement stunned the country. “The newspapers, when he said: ‘I have got cancer’, responded…
Don't Believe the Hype - 10 Persistent Cancer Myths Debunked

Driven by the evidence, not by rhetoric or anecdote, we describe what the reality of research actually shows to be true. Myth 1: Cancer is a man-made, modern disease While it’s certainly true that global lifestyle-related diseases like cancer are on the rise, the biggest risk factor for cancer is age. Myth 2: Superfoods prevent cancer Blueberries, beetroot, broccoli, garlic, green tea… the list goes on. Despite thousands of websites claiming otherwise, there’s no such thing…
Goodbye Year of Cancer. Hello Hope!

Death stared at me up close this year, says cancer survivor Minakshi Ray. What did that teach her about life? As I sit back and take stock of how 2014 treated me, I would say, it was a mixed bag. There have been losses and gains. I don't mean material losses or gains, rather I will remember the year in terms of the emotional journey. Following my battle of survival against breast cancer, my perspective on life has changed completely. The biggest realisation that has dawned…