Longitudinal Monitoring of Pan-Immune-Inflammation Value Forecast Outcomes for Patients with Head and Neck Cancer...

Background/Objectives: We aim to investigate whether tracking pan-immune-inflammation value (PIV) dynamics during radiotherapy (RT) can inform real-time prognosis in patients with head and neck cancer (HNC). Methods: We retrospectively reviewed the medical records of patients with HNC who received RT at our institution between 2005 and 2013. Temporal changes in the PIV throughout the RT were evaluated using the Friedman test and Wilcoxon signed-rank test. The PIV dynamics were quantified using PIV ratios, defined as the PIV at three distinct time points (PIV-2, PIV-4, and PIV-6) during treatment divided by the pretreatment PIV (PIV-0). Overall survival (OS) and progression-free survival (PFS) served as the primary and secondary endpoints analyzed. Results: A total of 676 patients with HNC were enrolled, with a median follow-up of 8.1 years. The PIV demonstrated a continuously ascending trend over time, with the most dramatic increase occurring six weeks after the start of RT. Compared with patients with a low PIV ratio at six weeks (PIV-6/PIV-0), those with a high PIV ratio showed more favorable survival outcomes (five-year OS: 58.9% versus 70.8%, p = 0.002; five-year PFS: 62.0% versus 71.1%, p = 0.013). The subgroup analyses yielded consistent results. Notably, the real-time risks of death and recurrence changed in parallel with the PIV dynamics. Multivariate analysis confirmed PIV-6/PIV-0 as an independent prognostic factor for both OS and PFS. Conclusions: Monitoring longitudinal PIV dynamics may assist in forecasting the OS and PFS in patients with HNC being treated with RT, thus enabling individualized, risk-adapted treatment management.