Eliminating consumption of betel quids in India could halve the country’s burden of oral cancer, preventing more than 37000 cases a year, a study has concluded.
Oral cancers account for the highest cancer related mortality among men aged 30-69 in India. Chewing of the betel quid (often referred to as “paan”) is fairly common; the quid is usually made up of areca nut, catechu, slaked lime, and often tobacco, which are placed in a betel leaf and folded into the characteristic triangular shape. Chewing paan releases carcinogenic nitrosamines from the areca nut that can cause pre-neoplastic changes.
To quantify the cancer risk of betel quid the researchers, from the International Agency for Research on Cancer in Lyon and King’s College and the WHO Collaborating Centre for Oral Cancer in London, conducted a meta-analysis of 50 papers that assessed the relation between oral or oropharyngeal cancer and betel quid, with added tobacco or without it.
The researchers found that in the Indian subcontinent (India, Pakistan, and Sri Lanka) the meta-relative risk of cancer of the oral cavity or oropharynx was 7.74 (95% confidence interval 5.38 to 11.13) for betel quid with tobacco and 2.56 (2.00 to 3.28) for betel quid without tobacco. Even after adjusting for alcohol and tobacco use, only a slight change was seen in the meta-relative risk (with tobacco 7.03 (4.68 to 10.56) and without tobacco 3.22 (2.11 to 4.92)).
A higher risk of buccal mucosa and cheek cancers was observed in the betel quid with tobacco group, which was not surprising, because it is the site where the quid is usually placed.
The risk of cancer was also found to be higher among women. In India the meta-relative risks were 4.92 (3.88 to 6.24) for men and 23.06 (5.94 to 89.58) for women in the betel quid with tobacco group. The difference was also seen in the betel quid without tobacco group: 2.25 (1.72 to 2.94) for men and 8.76 (2.97 to 25.80) for women. The researchers said that this could be because women are more susceptible to oral cancer than men, that they chew more quids a day, that they keep the quid in their mouth for longer, because of human papillomavirus prevalence, or because women have a lower background risk of oral and oropharyngeal cancers.
Half of oral cancers could be prevented if people stopped chewing betel quids, the researchers estimated.
Ganpathi Bhat, an honorary consultant medical oncologist and stem cell transplant physician at Jaslok Hospital and Research Centre, Mumbai, told the BMJ that the use of the betel leaf and nut were ingrained in Indian culture, as they were an integral part of Hindu religious and wedding ceremonies. Moreover, betel cultivation was important for the economy of several states, including Kerala and Assam, and in the Konkan belt (the coastal parts of Maharashtra, Goa, and Karnataka). He said that even youngsters who couldn’t smoke in public were taking to betel quid chewing because it was easily available and not prohibited by law.
Bhat said that stopping betel quid consumption in India would require education, legislation to ban its use, and the provision of other economic options for those whose livelihoods depended on cultivating the plant.
1. Guha N, Warnakulasuriya S, Vlaanderen J, Straif K. Betel quid chewing and the risk of oral and oropharyngeal cancers: a meta-analysis with implications for cancer control. Int J Cancer 3 Dec 2013, doi:10.1002/ijc.28643.
2. Dikshit R, Gupta PC, Ramasundarahettige C, Gajalakshmi V, Aleksandrowicz L, Badwe R, et al. Cancer mortality in India: a nationally representative survey. Lancet 2012;379:1807-16.
3. International Agency for Research on Cancer. Betel quid and areca nut. In: Personal habits and indoor combustions. Vol 100 E. A review of human carcinogens. IARC Monogr Eval Carcinog Risks Hum 2012;100(part E):1-538. http://monographs.iarc.fr/ENG/ Monographs/vol100E/mono100E-10.pdf.
Cite this as: BMJ 2013;347:f7536