The Impact of Pretreatment Low Body Mass Index on Cause-Specific Mortality in Patients with Squamous Cell Carcinoma of the Oral Cavity

Abstract

The association between the pretreatment body mass index (BMI) and oral squamous cell carcinoma (SCC) outcomes is controversial. We aimed to examine the association between BMI and cause-specific mortality due to cancer of the oral cavity and patterns of failure that correlate with increased mortality. We enrolled 2,023 East Asian patients in this multicenter cohort study. We used the cumulative incidence competing risks method and the Fine–Gray model to analyze factors associated with cause-specific mortality, local recurrence, regional metastasis, and distant metastasis as first events. The median follow-up period was 62 mo. The 5-year cause-specific mortality for patients with underweight was 25.7%, which was significantly higher than that for patients with normal weight (12.7%, P < 0.0001). The multivariate model revealed that underweight was an independent risk factor for cause-specific mortality and regional metastasis (P < 0.05). Moreover, patients with underweight displayed a 51% and 55% increased risk of cause-specific mortality and regional metastasis, respectively, compared with their normal weight counterparts. Local recurrence was not associated with the BMI categories; however, the incidence of distant metastasis inversely decreased with BMI value. In summary, being underweight at diagnosis should be considered a high-risk mortality factor for oral SCC.

Acknowledgments

We thank Dr. Souichi Yanamoto and Dr. Masahiro Umeda for their advice.

Authors’ Contributions

Conception and design: M. Okura. Statistical analysis and interpretation: M. Okura. Collection and assembly of data: KK, SR, M. Otsuru, TN, NY, TH, SY, EH, and YO. Administrative support: TK, MA, HK, KY, and MU. M. Okura was responsible for the conception of the study, obtaining funding, and overall supervision. All authors have read and approved the submitted manuscript.

Disclosure Statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by the Japan Society for the Promotion of Science under a grant (#18K09742) to M. Okura.