Why North East India has high prevalence of cancer cases
February 4 was World Cancer Day, and the increasing number of cancer cases in the North East is a matter of concern. Experts believe there is a need for detailed studies to find out the causes behind the high prevalence in the region. Experts also stressed the need to eradicate tobacco use, one of the key reasons behind the killer disease.
Last year, the Indian Council of Medical Research (ICMR) and National Centre for Disease Informatics & Research (NCDIR), Bengaluru, had projected that the number of new cancer cases in the North East region is likely to increase to 57,131 by 2025, in comparison to the estimated 50,317 in 2020.
These estimates are based on cancer data compiled by eleven Population-Based Cancer Registries (PBCRs) in all eight States.
The report titled “Profile of cancer and related health indicators in the North East Region of India” also includes data from seven hospital-based cancer registries (HBCRs) in Assam, Manipur, Mizoram and Tripura from 2012 to 2016.
“Yes, the scenario is very alarming. Several well-designed epidemiological studies combined with molecular biomarkers are needed to understand the high prevalence of cancer in the region,” said Dr Tapan Saikia, a medical oncologist and blood stem cell transplant physician, said.
A native of Assam, Dr Saikia is the Head of Medical Oncology and Research Director, Prince Ali Khan Hospital, Mumbai. He is also a pro bono visiting Professor and consultant at State Cancer Institute, Gauhati Medical College and Hospital, Assam.
North Eastern States have a high burden of cancer, the report says. The highest incidence rate in males (269.4 per 100,000 population) was recorded in Aizawl district in Mizoram, among females (219.8 per 100,000) in Papumpare district in Arunachal Pradesh.
Another important aspect the report points out is the disparity in cancer cases between males and females. The proportion of tobacco-related cancers was 49.3% in males and 22.8 % in females. Again, in all the NE States, cancer incidents were higher in males than in females, except in Manipur and Sikkim. “The sex disparity is a complex issue. Again, very well-designed population-based studies are needed to find out details. Hospital-based registries are skewed,” Dr Saikia says.
The prevalence of obesity among women aged 15-49 years was highest in Sikkim (34.7%) followed by Manipur (34.1%). While in men, it was highest in Sikkim (36.3%) and lowest in Meghalaya (13.9%). Sikkim had the highest prevalence of hypertension in men (41.6%) and women (34.5%), followed by Manipur (men 33.2% and women 23.0%). In all eight States, men had a higher blood sugar level when compared to women.
But how are obesity and hypertension linked to cancer ? Dr Saikia said that non-communicable diseases (NCD) are interrelated, especially diabetes and obesity, with cancer. “Additionally, diabetes and hypertension are interrelated.”
According to the report, the commonly occurring cancers among males were cancer of the oesophagus (13.6%) and lung (10.9%). In females, breast cancer was the leading cause (14.5%) followed by cervix uteri (12.2%).
Dr Saikia says, “Tobacco and alcohol are etiological factors for most NCDs, directly or indirectly. However, many cancers develop due to genetic predispositions. In recent years, several models have been discussed and published in high-impact value journals such as Nature and Science. In coming years, further understanding of molecular genetics in the development of cancers will clarify these issues.”
Less than 50% of households in Arunachal Pradesh, Assam, Meghalaya, Nagaland and Tripura were using clean fuel for cooking, mentions the report. So is poverty or poor economic condition another factor ?
Dr Saikia says, “There are multiple factors for diagnosis of cancer at advanced stages—socio-economic, poor education about health among laypeople, lack of required health care system for early diagnosis.”
The report mentions that the proportion of cancer patients seeking treatment outside the North East was highest for Sikkim (95.3%) and Nagaland (58.1%). For years, people have been generally travelling outside the region for treatment, so hasn’t the situation improved ? Dr Saikia said that many States in the country don’t have cancer-focused health care programs. “Of late, some States are waking up.”
During the diagnosis of breast, cervix, head and neck, stomach and lung cancers, less than one-third were localised, while the remaining were spread either nearby or distantly in the body.
Tobacco usage, both smokeless and chewing, is widely linked to cancer. In Assam, for example, offering tamul-paan (betel nut and leaf) with raw tobacco to guests is a common practice. People consume paan and are addicted to zarda across all ages, so much so that in the North East, tobacco is kind of engrained in the culture.
Oncosurgeon Dr Shekhar Salkar says, “All over India, the percentage of smoking cigarettes or bidis is less than 20%. The maximum use is of smokeless tobacco, such as gutka, paan masala, zarda, khaini, paan, etc. There is liquid tobacco found in States like Mizoram, where the cancer rates are high. In the North East, the use of tobacco rate is around 45-55 %. Even in weddings if you don’t serve tobacco, they consider it a taboo.”
Dr Salkar, the Chief of Department of Oncology at Manipal Hospital, Panaji, Goa, and president for the National Organisation for Tobacco Eradication, said it would take a long time for such habits to go as it is ingrained in the culture.
The Global Adult Tobacco Survey (GATS) India, 2016-17, had highlighted the high use of tobacco in the North East. The highest prevalence of tobacco use has been reported in Tripura (64.5%).
Tripura is followed by Mizoram at 58.7 %, Manipur 55.1 %, Assam 48.2 %, Meghalaya 47.0 %, Arunachal Pradesh 45.5 % and Nagaland 43.3 %. The all-India prevalence is 29%.
So how do we check this ? “We will have to continue our awareness programme. The people themselves must know that these are the side effects of tobacco. If we continue, we will have problems and suffer, and we have to stop all these habits,” Dr Salkar said.
The word cancer itself is scary for the general public. Do those with a family history of cancer have more chances of getting cancer? Dr Saikia concluded, “Cancer is a complex and multifactorial group of diseases. A simplified example — if a person has some genetic predilection for the development of particular cancer: if s/he is a heavy tobacco user, cancer will develop early. Otherwise, it might’ve manifested a few years later or never experienced clinical cancer.”
The writer is an independent journalist and video content creator based in Delhi-NCR.