‘Tobacco behind more than a quarter of India’s cancer cases’

Tobacco-related cancers constitute the highest burden among all types of the disease in India. As many as 27 per cent of cancer cases were caused due to tobacco consumption, according to a new report released by the National Cancer Registry of India (NCRI).

Background

• Cancer is the second leading cause of death globally. According to the World Health Organisation (WHO), cancer accounted for an estimated 9.6 million deaths, or one in six deaths, in 2018.
• The most commontypes of cancer in men are lung, prostate, colorectal, stomach and liver cancer while breast, colorectal, lung, cervical and thyroid cancer are the most common types among women.
• In a recent report, WHO warned that the world may witness a 60% increase in cancer cases over the next two decades if the current trend continues.
• The latest estimates of the National Cancer Registry Programme Report 2020 are released by the ICMR in association with National Centre for Disease Informatics & Research (NCDIR) Bengaluru.
• The report released the cancer prevalence landscape by taking into account cases registered from 2012-2016.
  • The report estimates that tobacco-related cancers will contribute 3.7 lakh (27.1 per cent) of the total cancer burden in 2020.
  • Cancers related to use of any form of tobacco were highest in the northeastern region of the country and in higher proportion in men.
• Earlier this year, a WHO report had also revealed a high burden of tobacco-related head and neck cancers in India, particularly oral cancerin men and of cervical cancer in women. 
• Both of these cancer types are associated with lower socioeconomic status, the WHO report stated.

Cancer Basics

• The cells in our bodies all have certain jobs to do. Normal cells divide in an orderly way. They die when they are worn out or damaged, and new cells take their place.
• Cancer is when the cells start to grow out of control.
• The cancer cells keep on growing and making new cells. They crowd out normal cells. This causes problems in the part of the body where the cancer started.
• Simply put, Cancer is the uncontrolled growth of abnormal cells anywhere in a body.
• Cells become cancerous due to the accumulation of defects, or mutations, in their DNA. Certain:
  • inherited genetic defects (for example, BRCA1 and BRCA2 mutations),
  • infections,
  • environmental factors (for example, air pollution), and
  • poor lifestyle choices -- such as smoking and heavy alcohol use -- can also damage DNA and lead to cancer.

Types of Cancer

• Carcinoma is a cancer that starts in the skin or the tissues that line other organs.
  • Lung cancer: A cancer that begins in the lungs and most often occurs in people who smoke.
  • Breast Cancer: A cancer that forms in the cells of the breasts.
  • Prostate cancer: A cancer in a man’s prostate, a small walnut sized gland that produce seminal fluid.
• Sarcoma is a cancer of connective tissues such as bones, muscles, cartilage, and blood vessels.
• Leukemia is a cancer of bone marrow, which creates blood cells.
• Lymphoma and myeloma are cancers of the immune system.
• Brain and spinal cord cancers– these are known as central nervous system cancers

Key-Highlights of the Report

• The estimates of the National Cancer Registry Programme Report 2020 projected that cancers will rise by 12 per cent to 1,569,793 cases in 2025, from 1,392,179 in 2020. 
• The report has included data from 28 population-based cancer registries (PBCRs) and 58 hospital-based cancer registries (HBCRs) in India.
• The PBCR takes into account, the number of cancer cases in a given geographical unit, for instance, Delhi. It can be a district or even a state.
• The HBCR takes into account, the number of cases that go to a particular hospital irrespective of their geographical background. 
• The PBCR in Delhi registered the maximum number of cases (60,097), followed by Mumbai (53,714), Chennai (31,271), Bengaluru (29,049) and Thiruvananthapuram (27,833).

The most common cancer types

• Gastro-intestinal tract cancers (19.7 per cent) and breast cancer (14.8 per cent) are the other most prevalent cancers in India.
• Lymphoid and haematopoietic malignancies (immune system and blood cancers), cervix cancers and ovarian cancers are the other common cancers in India.
• Most common among male: The cancers of the lungs, mouth, stomach and oesophagus.
  • Mizoram’s Aizawl district topped in terms of cancer incidence per 100,000 population in males, followed by the districts of East Khasi Hills in Meghalaya and Kamrup in Assam, the state of Mizoram, Papum Pare district in Arunachal Pradesh, Meghalaya state, Delhi, Thiruvnanthapuram district in Kerala and Cachar district in Assam. 
• Most common among female: Cancers of the breast and cervix uteri.
  • Papum Pare had the worst cancer rate for females, followed by followed by Aizawl, Mizoram, Kamrup, Bengaluru, Delhi, Hyderabad and Chennai.
• Mouth cancers were the leading cancers in eight sites: The districts of Ahmedabad Urban, Aurangabad, Osmanabad & Beed, Barshi Rural, Pune, Wardha, Bhopal and Nagpur.
• Lung cancer was the leading cancer in eight other sites including the state of Delhi and the districts of Kollam, Thiruvananthapuram, Bengaluru, Chennai and Kolkata.
• The former is believed to be mostly caused by chewable tobacco and the latter by smoked tobacco. Thus, 16 out of 28 sites were affected directly because of tobacco in one or the other form. 
• Overall, lung and head and neck cancers were on the rise while stomach cancers were on the decline. 
• Breast cancers were leading female cancers in 19 out of 28 sites. In the remaining sites, cervix cancer was leading. Overall, while breast cancers witnessed a significant upward trend, cervix cancer cases declined. 
• Childhood cancers are also on the rise. The Delhi PBCR recorded the highest proportion of childhood cancers in both the 0-14 years (3.7 per cent) and the 0-19 years age group (4.9 per cent).
• From the HBCR data, leukaemia was the most common diagnosis of cancer, both in the 0-14 (boys, 46.4 per cent; girls, 44.3 per cent) and in the 0-19 age group (boys, 43.2 per cent; girls, 39.2 per cent).

Is Cancer a notifiable disease?

• Majority of states in India have not declared cancer as a notifiable disease.
• So far, only nine States in India have cancer as a notifiable disease so far either as administrative order or Gazette notification, including Karnataka.
  • A notifiable disease is any disease that is required by law to be reported to government authorities. The collation of information allows the authorities to monitor the disease, and provides early warning of possible outbreaks.

How Tobacco is killing people?

• Tobacco use, including smokeless tobaccoproducts, are linked to various types of cancer, including cancer of the lung, larynx (voice box), mouth, esophagus, throat, bladder, kidney, liver, stomach, pancreas, colon and rectum, and cervix, as well as acute myeloid leukemia.
• Tobacco has been described by WHO as “the single greatest cause of preventable disease in the developed world”.
• It has been universally regarded that Tobacco is one of the major health hazards and is responsible directly or indirectly for an estimated 8 lakh deaths annually in the country. 
• There are 4000 chemicals, 200 of which are poison and 69 certified carcinogens in tobacco.
• When one smokes, these toxic chemicals pass through lungs and are absorbed into bloodstream and carried around body.
• Every cigarette is an elaborate chemical factory, designed to cause damage and affect every organ in body.
• Poisons in cigarette smoke can weaken the body’s immune system, making it harder to kill cancer cells. When this happens, cancer cells keep growing without being stopped.
• Poisons in tobacco smoke can damage or change a cell’s DNA.
  • DNA is the cell’s “instruction manual” that controls a cell’s normal growth and function.
• When DNA is damaged, a cell can begin growing out of control and create a cancer tumor.
• Toxic gases damage the cilia, while Tar, the solid particle in tobacco smoke coats lungs like soot in a chimney. Some chemicals in your cigarette are:
  • Ammonia – commonly used in toilet cleaners
  • Cyanide – used as rat poison
  • Formal de hyde – used in laboratories for preservation of dead specimens
  • Nicotine – “the Hook”, habit forming, addictive drug

Interventions to prevent cancer

• Controlling tobacco use (responsible for 25% of cancer deaths)
• Vaccinating against hepatitis B to prevent liver cancer
• Eliminating cervical cancer by vaccinating against HPV
• Screening and treatment
• Implementing high-impact cancer management interventions that bring value for money
• Ensuring access to palliative care including pain relief.

Conclusion

In order to change the current cancer landscape in India, cancer care needs to be embedded in the community through a distributed care delivery system. In order to achieve these goals, innovation in a model of distributed cancer care, intensive efforts towards cancer prevention and early detection, and radical new policies on procurement and pricing of medical consumables and drugs are just a few measures that are necessary to make cancer care accessible and affordable in India and other LMICs.