Recently, the National Centre for Disease Informatics and Research (NCDIR) and the Indian Council of Medical Research (ICMR) released a report that analyses the profile of cancer patients in India. The report considered only 6.1 lakh cases out of the total 13.3 lakh cancer cases that were registered in the 96 participating hospitals, due to quality and completeness of the data.
According to the World Health Organization (WHO), the term ‘Cancer’ is used to refer to a large group of diseases that can affect any part of the body. It is defined by the rapid creation of abnormal cells which grow beyond their usual boundaries. It can then invade the adjoining parts of the body and spread to other organs. The spread of cancer to new parts of the body is known as metastasis, which is the primary cause of death from cancer.
Cancers claimed the lives of 1 crore persons globally in 2020
In 2020 alone, nearly 10 million deaths or one crore deaths globally were because of cancer. Further, around 70% of deaths from cancer occur in low- and middle-income countries. In 2020 alone, lung cancer claimed the lives of over 18 lakh persons. The second most cause of cancer death was colon and rectum cancer which resulted in the death of 9.35 lakh persons followed by liver cancer that claimed the lives of 8.3 lakh persons. Stomach cancer resulted in the death of 7.69 lakh persons worldwide, and breast cancer caused 6.85 lakh deaths. Tobacco use, high Body Mass Index, alcohol consumption, lack of physical activity, and poor fruit and vegetable intake, are responsible for one in three deaths due to cancer. It can be acute (sudden onset), sub-acute (slow onset), or chronic (long period) and multifactorial in origin.
Six site-specific cancers accounted for over one crore cancer cases reported in 2020
WHO had earlier projected that cancer rates may rise by at least 60% in the next two decades. In terms of the new cancer cases reported globally in 2020, the most common cancer was breast cancer. 22.6 lakh cases of breast cancer were reported followed by 22.1 lakh cases of lung cancer. About 19.3 lakh cases of colon and rectum cancer, 14.1 lakh cases of prostate cancer, 12 lakh cases of non-melanoma skin cancer and 10.9 lakh cases of stomach cancers were also reported. In other words, six site-specific cancers alone accounted for over one crore cancer cases reported in the year 2020 while according to the International Classification of Diseases for Oncology, there are more than 600 types of cancer.
NCDIR-ICMR recently released a comprehensive report of anatomic site-wise cancers
Recently, the National Centre for Disease Informatics and Research (NCDIR) and the Indian Council of Medical Research (ICMR) released ‘Clinicopathological Profile of Cancers in India: A report of the Hospital Based Cancer Registries, 2021’. The report gives a comprehensive overview of the distribution of cancer cases in India based on data from participating hospitals and cancers in sites associated with tobacco use. Furthermore, a detailed anatomic site-wise clinical description for eight systems/specific organs, viz; cancers of head and neck, gastrointestinal tract, lungs, gynaecological and breast, prostate, kidney and urinary bladder, brain and nervous system, and thyroid cancers have been covered in the report. The data is intended to help understand the gravity of the disease in the country and aid in decision-making, policy formulation, research, and improving cancer care.
Cancer registries are maintained by countries and collate data on incidence, type, and mortality due to cancer in the country. In India, the National Cancer Registry Programme Report (NCRP) provides information on estimated incidence and mortality in India. For this report, data on cancer cases from 96 Hospital Based Cancer Registries under the National Cancer Registry Programme (NCRP) has been collected for the seven-year period from 2012 to 2019. The data pertains to all diagnosed and treated cases of confirmed malignancies reported to these centres across the country during this period.
13.9 lakh cases of Cancer are estimated in India in 2020
The report states that the estimate of cancer cases in the country is 13.9 lakhs as of 2020, up from 13.25 lakh cases in 2018. Projections suggest that the incidence of cases would increase by 13% to reach 15.7 lakh cases by 2025. For this report, the NCDIR considered only 6.1 lakh cases out of the total 13.3 lakh cancer cases that were registered in the 96 participating hospitals, due to the quality and completeness of the data.
The proportion of all cancer cases is higher in males & most due to Tobacco usage
The proportion of all cancer cases was higher in males with 3.19 lakh cases (52.4%) as compared to 2.9 lakh cases (47.4%) in females. This trend is evident in the cases of childhood cancers as well. Childhood cancers or incidence of cancers among children aged 0 to 14 years accounted for 4% of all cancers, which is around 24,268 cases. Leukaemia or blood cancer accounted for around 45% of all the childhood cancers in both genders in the said age group. Lymphoma accounted for 16.4% of childhood cancer in boys while malignant bone tumours accounted for 8.9% of cancers among girls. About 70% of childhood kidney cancer cases were reported in the 0-4 years age group. About 1 in 3 cancers in the brain and nervous systems were reported in the 5-9 years age group.
The data from the report indicates that most cases of cancer in India are due to tobacco usage. It is known that tobacco has high carcinogenicity with over 69 carcinogenic agents such as amines, hydrocarbons, aldehydes, etc. According to the National Non-communicable Disease Monitoring Survey (NNMS) 2017-2018, close to one-third of adults between 18-69 years used either smoked or smokeless forms of tobacco, and 28% used tobacco daily.
Data indicates that Cancers in sites associated with tobacco use comprised 48.7% of cancers among males and 16.5% among females. Overall, 33.3% of the cancer cases analysed in the 2021 report, over 2 lakhs, were because of tobacco usage. On the other hand, a NCRP report from 2020 estimated that 27.1% of all cancer cases in India, amounting to 3.77 lakh cases, were due to tobacco usage. Further, the NCRP report from 2020 projected that the incidence would increase to 4.27 lakhs by 2025. The latest report has also made similar projections. Based on the tobacco use in 2021, it is estimated that by 2025 there would be 3.14 lakh cases in males and 1.14 lakh cases in females contributing to 27.2% of the projected cancer cases in India.
1 in 2 cancer cases in the Northeast is due to tobacco usage
Geographical distribution of the 6 lakh odd cases analysed in the 2021 report shows that more than 50% of the cancer cases in Northeast India were due to tobacco usage, followed by the West with 36.9% cases attributable to tobacco. The proportion was the lowest in the East with 25.3% cases attributable to tobacco. A total of 32.9% of the cases in North and 28.6% cases in the South were due to tobacco usage. However, in terms of the number of cases, the South had the highest incidence with close to 62,000 cases (30% of all tobacco-related cases) due to tobacco usage and the Central region had the lowest with over 11,400 cases. The number of cases in India attributable to tobacco usage is given in the following chart.
One-third of cancers in males were in the head & neck region while gynaecological & breast cancers account for half the cancers in females
The highest proportion of cancer from almost all sites were reported in the age group 45 to 64 years. The anatomic site-wise analysis reveals the following.
- Except for gall bladder and thyroid cancers, the relative proportion of site-specific cancers was higher in males than females.
- Cancers of the head and neck region accounted for over 21.3% of all cancers. Nearly one third (31.2%) of the cancers among males was that of head and neck, and cancer of the lung accounted for over 10% of the cancers among males.
- Over 80% of the cases of prostate cancer were reported in men aged above 60 years.
- Gynaecological and breast cancers accounted for over half of all cancers in women. A further 25.4% of the cases among women were breast cancer followed by 15.2% cases of cervical cancer. Among females aged below 25 years, ovarian cancer was more prevalent, and for older females, breast cancer was more common. Over 51.2% of thyroid cancers reported among females was reported in the 20 to 45 years age group.
- Liver cancers accounted for over half the cancers reported in the less than 20 years age group and rectal cancers accounted for over a quarter in the 20 to 34 years age group, irrespective of sex.
- About 23.3% of kidney cancers were reported among persons aged below 20 years.
- Cancers of the brain and nervous system accounted for less than 2% of the cancers.
The report also noted that chemotherapy was the most typical treatment modality for many cancers, including cancers of the liver, gallbladder, stomach, lung, and childhood cancers. The report further notes that most cancer patients were initiated on cancer-directed treatment within 8 to 30 days of diagnosis.
Cancer burden can be reduced
According to the WHO, between 30% to 50% of cancers can be prevented by avoiding risk factors and implementing existing evidence-based prevention strategies. Some of the measures include limiting tobacco usage, encouraging an active lifestyle, and vaccination against the HPV virus. Early detection of cancer and appropriate treatment and care of patients who develop cancer could help reduce cancer burden as many cancers have high chances of curing provided it is detected and treated on time.