Impact of obesity on the survival of patients with early-stage squamous cell carcinoma of the oral tongue

Abstract

Background: Although obesity increases risk and negatively affects survival for many malignancies, the prognostic implications in squamous cell carcinoma (SCC) of the oral tongue, a disease often associated with prediagnosis weight loss, are unknown.

Methods: Patients with T1-T2 oral tongue SCC underwent curative-intent resection in this single-institution study. All patients underwent nutritional assessment prior to surgery. Body mass index (BMI) was calculated from measured height and weight and categorized as obese (≥ 30 kg/m(2) ), overweight (25-29.9 kg/m(2) ), or normal (18.5-24.9 kg/m(2) ). Clinical outcomes, including disease-specific survival, recurrence-free survival, and overall survival, were compared by BMI group using Cox regression.

Results: From 2000 to 2009, 155 patients (90 men, 65 women) of median age 57 years (range, 18-86 years) were included. Baseline characteristics were similar by BMI group. Obesity was significantly associated with adverse disease-specific survival compared with normal weight in univariable (hazard ratio [HR] = 2.65, 95% confidence interval [CI] = 1.07-6.59; P = .04) and multivariable analyses (HR = 5.01; 95% CI = 1.69-14.81; P = .004). A consistent association was seen between obesity and worse recurrence-free survival (HR = 1.87; 95% CI = 0.90-3.88) and between obesity and worse overall survival (HR = 2.03; 95% CI = 0.88-4.65) though without reaching statistical significance (P = .09 and P = .10, respectively) in multivariable analyses.

Conclusions: In this retrospective study, obesity was an adverse independent prognostic variable. This association may not have been previously appreciated due to confounding by multiple factors including prediagnosis weight loss.

Keywords: body mass index; head and neck neoplasms; obesity; prognosis; squamous cell carcinoma of the head and neck; tongue neoplasms.

Figure 1

Consolidated Standards of Reporting Trials (CONSORT) diagram of current study. Abbreviations: BMI; body mass index.

Figure 2

A. Disease specific survival after curative resection and neck dissection for oral tongue squamous cell carcinoma according to body mass index at time of surgery (N = 155). B. Recurrence free survival (N = 155). C. Overall survival (N=155). Abbreviations: HR, hazard ratio; CI, confidence interval.

Figure 3

Multivariate hazard ratios (HRs) stratified by body mass index for disease specific survival, recurrence free survival, and overall survival in patients who underwent curative resection and neck dissection for oral tongue SCC (N = 155). Covariates include age, black race, smoking history, diabetes, T stage, tumor grade, perineural invasion, vascular invasion, lymph node metastases, and use of post-operative radiation.