Dynamic change of the systemic immune inflammation index is a risk factor for patients with oropharyngeal cancer: a case control study and an additional HPV-status subgroup analysis

BACKGROUND: The study aimed to analyze the relationship between the dynamic systemic immune inflammation index (SII), human papillomavirus (HPV) infection, and the prognosis of oropharyngeal cancer patients. METHOD: We retrospectively obtained the data for 131 patients treated with curative treatments and calculated their SII values based on results acquired approximately 9 months after the first treatment. The entire cohort was divided into groups according to dynamic SII and HPV infection, and their prognoses were compared. RESULTS: The high SII group, particularly the persistently high SII group, had a poor prognosis, and static SII levels cannot fully reflect the prognosis of patients with oropharyngeal cancer. In HPV− patients, unfavorable dynamic SII and the site of tumor locating at the tongue base were all significantly associated with decreased disease-free survival. In contrast, no characteristic was presented as a poor prognostic factor for disease-free or overall survival in HPV+ patients. CONCLUSION: Dynamic SII values are more comprehensive prognostic indicators for oropharyngeal cancer patients, particularly HPV− patients. It could imply that an HPV− oropharyngeal cancer patient who experienced unfavorable dynamic changes in SII should receive more frequent tests or more advanced therapies.