Cancer incidence highest in northeast India, finds study

Women comprised 51.1% of the total cancer cases and 45 per cent of the deaths. Men, on the other hand, accounted for 48.9% of the disease incidents and 55 per cent of the deaths due to it.

Northeast India's Aizawl, East Khasi Hills, Papumpare, Kamrup Urban, and Mizoram consistently recorded the highest rates of cancer between 2015 and 2019, according to a study.

The cross-sectional study used data from 43 population-based cancer registries (PBCRs) across India.

Between January 1, 2015, and December 31, 2019, as many as 7.08 lakh cancer cases and 2.06 lakh deaths were reported from 43 PBCRs across India. Women accounted for a higher proportion of cancer cases, and men for deaths due to it.

Women comprised 51.1 per cent of the total cancer cases and 45 per cent of the deaths. Men, on the other hand, accounted for 48.9 per cent of the disease incidents and 55 per cent of the deaths due to it.

The study obtained population-at-risk data from the Census of India, and the findings were assessed by registry area.

According to the study, the lifetime risk of developing cancer in India was 11.0 per cent.

However, in Mizoram, the reported lifetime risk was a staggering 21.1 per cent in males and 18.9 per cent in females. Aizawl district reported the highest age-adjusted incidence rate (AAIR) in both males and females.

The most common types of cancers were oral, lung, and prostate in males and breast, cervical, and ovarian in females, the study found.

Among metropolitan cities -- with a population of over 1 million-- Delhi had the highest overall cancer AAIR for males, while Srinagar recorded the highest AAIR for lung cancer.

Oral cancer showed significant increases in 14 PBCRs among males and four PBCRs among females.

The analysis revealed a distinct pattern in the leading cancer sites across India. Among males, lung cancer emerged as the most frequently diagnosed form of the disease in the southern regions and metropolitan cities, including Visakhapatnam, Bengaluru, Malabar, Kollam, Thiruvananthapuram, Chennai, and Delhi.

A previous study had found that patients in India tend to present with lung cancer about a decade earlier than those in Western populations, with a median age ranging from 54 to 70 years.

Additionally, half of the patients were diagnosed with advanced-stage disease. A systematic review and meta-analysis on tobacco use revealed a significantly higher risk of respiratory system cancers.

Mouth cancer is the predominant form of cancer in western (Ahmedabad Urban, Bhopal, Nagpur, and Wardha), central (Barshi Rural, Mumbai, Aurangabad, Osmanabad and Beed, Pune, Sindhudurg, and Ratnagiri), and certain northern (Prayagraj and Varanasi) regions, the study found.

It underlined that since tobacco and alcohol use are major risk factors, it is vital to promote widespread education about their harmful effects. Furthermore, quitline services and the implementation of early detection programs are critical for effective prevention and control.

In India, breast, cervical, and ovarian cancers have been consistently ranked among the top three most common forms of cancers in women, with disparities observed in survival rates for breast and cervical cancers.

The increasing incidence of breast cancer and decreasing incidence of cervical cancer were more associated with generational shifts in risk factors than period effects, the researchers said.

Effective cancer control in India requires coordinated efforts, focusing on public awareness, prevention, and early detection. Awareness campaigns help reduce stigma and encourage timely health-seeking behaviour, the study underlined.

Beyond prevention, upgrading existing cancer care facilities and expanding services in high-incidence regions is vital to ensure equitable access to quality and affordable care.

However, cancer care delivery faces challenges, including regional disparities, socioeconomic inequalities, low awareness, and varied health-seeking patterns.

Addressing these issues requires a collaborative, data-driven approach to build equitable and accessible cancer care across India, it stated.

Globally, cancer contributes to approximately 10 million deaths each year. In 2022, the Global Cancer Observatory (GCO) pegged the total number of cancer cases worldwide at approximately 20.0 million and projected these to increase to 32.6 million by 2045.

The Southeast Asia region is estimated to have a total of 2.4 million new cancer cases and 1.5 million cancer deaths.

Cancer incidence and mortality in this region are estimated to increase to 4 million new cases and 2.7 million deaths by 2045. Concurrently, the GCO estimated that the incidence of cancer in India will increase to approximately 2.46 million cases by 2045.

India ranks second in Asia and third in the world in terms of the number of cancer cases, and the likelihood of developing cancer during one's lifetime is approximately 11 per cent.