Host Factors Independently Associated With Prognosis in Patients With Oral Cavity Cancer

Abstract

The association and interaction of host characteristics with prognosis in patients with oral cavity squamous cell carcinoma (OSCC) are poorly understood. There is increasing evidence that host characteristics are associated with treatment outcomes of many cancers. To examine the host factors associated with prognosis in patients with OSCC and their interactions to create a numerical index that quantifies the prognostic capacity of these host characteristics. This retrospective cohort study included patients with OSCC treated surgically at a tertiary care center from January 1, 1998, to December 31, 2015. From a departmental OSCC database of 1377 previously untreated patients, 68 patients with missing data on any host variable of interest within a month before the start of treatment were excluded, leaving 1309 patients. Data analysis was performed from October 21, 2019, to December 10, 2019. Primary surgery for OSCC. Overall survival (OS) was the primary end point, and disease-specific survival (DSS) was the secondary end point. Optimal cutoffs for each variable were identified using recursive-partitioning analysis with the classification and regression tree method using OS as the dependent variable. Body mass index (BMI) and pretreatment peripheral blood leukocyte count, platelet count, hemoglobin level, and albumin level were analyzed. A host index (H-index) was developed using independent factors associated with OS. A total of 1309 patients (731 [55.8%] male; mean [SD] age, 62 [14.3] years) participated in the study. When including all the host-related factors in a multivariable analysis, all except BMI (hazard ratio [HR], 1.14; 95% CI, 0.80-1.63) were independently associated with outcomes. For example, compared with a hemoglobin level of 14.1 g/dL or greater, the HR for a level of 12.9 to 14.0 g/dL was 1.42 (95% CI, 1.13-1.77) and for a level of 12.8 g/dL or less was 1.51 (95% CI, 1.18-1.94), and compared with an albumin level of 4.3 g/dL or greater, the HR for a level of 3.7 to 4.2 g/dL was 1.18 (95% CI, 0.95-1.45) and for a level of 3.6 g/dL or less was 3.64 (95% CI, 2.37-5.58). An H-index of 1.4 or less was associated with a 74% 5-year OS, an H-index of 1.5 to 3.5 with a 65% 5-year OS, and an H-index of 3.6 or higher with a 38% 5-year OS; for DSS, the 5-year survival was 84%, 80%, and 64%, respectively. Compared with patients with an H-index score of 1.4 or less, patients with H-index scores of 1.5 to 3.5 (hazard ratio, 1.474; 95% CI, 1.208-1.798) and 3.6 or higher (hazard ratio, 3.221; 95% CI, 2.557-4.058) had a higher risk of death. The findings suggest that pretreatment values of neutrophils, monocytes, lymphocytes, hemoglobin, and albumin are independently associated with prognosis in patients with OSCC. The interactions between these host factors were incorporated into a novel H-index that quantified the prognostic capacity of host characteristics associated with OSCC.