Reversal of head and neck cancer risk after the cessation of use of smokeless tobacco and betel quid use: meta-analysis

The use of smokeless tobacco and betel quid is a significant risk factor for head and neck cancer, posing a major global public health concern. This meta-analysis evaluates the impact of cessation of the use of these products on head and neck cancer risk to guide interventions. Case–control and cohort studies were found through PubMed, Scopus, and Embase databases. Two independent reviewers screened studies and then extracted data. RRs and 95% confidence intervals (CI) for different product cessation were calculated from raw data and meta-analyzed by using random-effects models. A total of 13 studies met the inclusion criteria. Findings were predominantly derived from Asian (n = 9) studies in which betel quid use is widespread. Results showed reduced head and neck cancer risk following cessation of betel quid use with (RR = 0.66; 95% CI, 0.54–0.81) or without tobacco (RR = 0.73; 95% CI, 0.56–0.95). However, other tobacco chewing products showed an RR of 1.07 (95% CI, 0.75–1.53). Long-term cessation (≥20 years) conferred substantial benefits (RR = 0.37; 95% CI, 0.22–0.61; risk estimates = 4). The study highlights the importance of cessation programs and targeted interventions to encourage smokeless tobacco quitting. Future research includes conducting detailed subgroup analyses based on cancer subsites and smokeless tobacco product types.