An analysis of the impact of risk factors on the occurrence, progression, and treatment outcomes of oral squamous cell carcinoma using data from the Oral Cancer Registry in Japan

Abstract Background It is well known that smoking, alcohol consumption, eating green and yellow vegetables, and local irritation are risk factors for oral cancer. However, insufficient data was provided on whether these risk factors also influence the progression of the disease and its prognosis. The aim of this study is to investigate the role of risk factors, including smoking, alcohol, green/yellow vegetables, and chronic dental trauma, on the occurrence, progression, and treatment outcomes of oral squamous cell carcinoma (OSCC). Methods Data from 2,601 patients registered in the Japanese Oral Cancer Registry in 2018 who underwent a five-year follow-up survey were analyzed. The results of another health survey were used as a control to compare the effects of the risk factors on cancer development. Results The smoking rate among OSCC patients was significantly higher than that in the control group, except for elderly females. The prevalence of heavy alcohol consumption among OSCC patients was also significantly higher than that in the controls. OSCC patients consumed vegetables more frequently than the control group. Chronic dental trauma was potentially involved in the development of OSCC in 34.5% of patients. Significant correlations were found between the clinical stage of the tumor and both smoking volume and vegetable intake. The higher the smoking volume and the lower the vegetable intake, the more advanced the cancer. Furthermore, the incidence of double cancers was positively correlated with the volume of smoking. Smoking was the only factor that significantly affected the treatment outcomes. Conclusions These findings indicate that cigarette smoking can significantly influence the occurrence and progression of OSCC. Heavy alcohol consumption may also affect oral carcinogenesis. The effect of green and yellow vegetable intake on OSCC remains unclear. Smoking affects not only the development and progression of OSCC, but also its treatment outcomes.