The predictive usefulness of the novel “combined hemoglobin‐to‐platelet ratio and maximum mouth opening index” on prevalence of radiation induced trismus in patients with nasopharyngeal cancer

Abstract

AbstractObjectivesTo explore how well a unique combination of hemoglobin‐to‐platelet ratio (HPR) and pretreatment maximum mouth opening (MMO) predicts the prevalence of radiation‐induced trismus (RIT).Patients and methodsHPR and MMO cutoff values (0.54 and 40.7 mm) divided patients into two groups. To develop the novel HPR‐MMO index, four combinations of these factors were tested for predictive power: Group 1: HPR > 0.54 and MMO > 40.7 mm; Group 2: HPR ≤ 0.54 but MMO > 40.7 mm; Group 3: HPR > 0.54 but MMO ≤ 40.7 mm; Group 4: HPR ≤ 0.54 and MMO ≤ 40.7 mm.ResultsData of 198 patients with LA‐NPC was analyzed retrospectively. RIT rates for Groups 1 to 4 were 10.2%, 15.2%, 25%, and 59.4%. Groups 2 and 3 were merged to generate HPR‐MMO index because of statistically equivalent RIT rates: Low‐risk: HPR > 0.54 and MMO > 40.7 mm; Intermediate‐risk: HPR ≤ 0.54 but MMO > 40.7 mm or; HPR > 0.54 but MMO ≤ 40.7 mm; High‐risk: HPR ≤ 0.54 and MMO ≤ 40.7 mm. It was revealed that the low‐, high‐, and intermediate‐risk group's RIT rates; 10.2%, 59.4%, and 19.2%, respectively.ConclusionThe novel HPR‐MMO index may to classify LA‐NPC patients into low, intermediate, and high‐risk RIT groups.