OBJECTIVE
The significance of pre-hemoglobin-to-platelet ratio (HPR) in predicting the occurrence of radiation-induced trismus (RIT) in locally advanced nasopharyngeal carcinoma patients (LA-NPC) who received concurrent chemoradiotherapy (C-CRT).
METHODS
Records of LA-NPC patients with oral examination before and after C-CRT were analyzed. Maximum mouth openings (MMO) were measured before and after C-CRT to confirm RIT status, with an MMO of ≤35 mm defined as RIT. HPR values were calculated on the first day of C-CRT. The relationship between the HPR values and RIT status was discovered using the receiver operating characteristic curve analysis.
RESULTS
A total of 43 patients RIT cases among 198 individuals were diagnosed. The optimal HPR cutoff that stratified the patients into two groups was 0.54. RIT incidence was found to be significantly higher in the HPR≤0.54 group than its HPR>0.54 counterpart(P<0.001). Univariately T3-4 stage, mean masticator apparatus dose>57.2Gy, and pre-C-CRT MMO≤40.7 mm was found as the other significant correlates of increased RIT rates(P<0.05). All four variables seemed to be independently connected to greater RIT incidence in multivariate analysis (P<0.05, for each).
CONCLUSION
The risk of post-C-CRT RIT may be significantly increased when pre-treatment HPR levels are low.