Alcohol Consumption, ALDH2 Polymorphism as Risk Factors for Upper Aerodigestive Tract Cancer Progression and Prognosis

The upper aerodigestive tract (UADT) is highly susceptible to multiple primary cancers originated from squamous epithelia and constitutes a field of cancerization. Patients with head and neck cancer (head and neck squamous cell carcinoma, HNSCC) are at high risk of developing multiple cancers in the esophagus (esophageal squamous cell carcinoma, ESCC). Conversely, esophageal cancer patients are prone to develop multiple primary tumors in the head and neck region. The East Asian-specific dysfunctional ALDH2*2 missense mutation is a genetic risk factor for UADT cancer. It is not only associated with increased incidences of UADT cancer, but is also implicated in faster cancer progression and poorer prognosis. Alcohol use is a major lifestyle risk factor which causes UADT cancer among ALDH2*2 carriers. The accumulation of the immediate metabolite of alcohol, acetaldehyde, is likely the genotoxic agents that is involved in the process of tumorigenesis. This review summarizes recent publications on the risk and association of ALDH2*2 mutation, alcohol consumption in synchronous, metachronous UADT cancer. Possible molecular mechanisms involved in cancer initiation, progress and prognosis are discussed. The review also highlights a need for precision medicine-based preventive and therapeutic strategies by integrating lifestyle and genetic risk factors, such as alcohol consumption, genotypes of the alcohol metabolizing genes, ADH1B and ALDH2, into a risk assessment model for better screening, surveillance and treatment outcome.

Automated summary

The upper aerodigestive tract (UADT) is highly susceptible to multiple primary cancers. Head and neck cancer (HNSCC) patients are at high risk of developing esophageal cancer (ESCC) and vice versa. The ALDH2*2 missense mutation is a genetic risk factor for UADT cancer and is associated with increased incidence, faster progression, and poorer prognosis. Alcohol use is a major lifestyle risk factor in ALDH2*2 carriers and the genotoxic agent acetaldehyde likely plays a role in tumorigenesis. Precision medicine-based strategies integrating lifestyle and genetic risk factors, such as alcohol consumption and ADH1B and ALDH2 genotypes, are needed for better screening, surveillance, and treatment outcome.