Predictors of survival among head and neck cancer patients after radiotherapy based on health-related quality of life indices and symptoms-specific outcomes: a systematic review.

Purpose: The association between health-related quality of life (HQoL) and overall survival (OS) among head and neck cancer (HNC) patients remains an important yet complex topic. This study aims to comprehensively analyze the prognostic effects of HQoL indices and symptoms-specific outcomes on overall survival in HNC patients.

Methods: A systematic literature search was conducted in PubMed, Web of Science and Scopus databases. The QUIPS tool was used to assess the risk of bias in the prognostic studies. The variables from the HQoL assessments included as predictors of OS were recorded. Different phases of measurements either pre or post-treatment (3 to > 12 months after completion) were also classified to observe the patterns. This review utilized a proposed best-evidence synthesis in which the consistency of significant results from multivariate analysis was observed. Each index that shows > 75% proportion of high-quality studies with same result is classified as strong evidence.

Results: Following an extensive search yielding 440 articles, the rigorous screening process identified 32 studies involving 12,206 HNC patients. This review underscores the pivotal role of higher post-treatment physical functioning predicting OS, which is supported by strong evidence and consistent findings. Three indices showed moderate evidence which are pretreatment physical function, post-treatment general HQoL and post-treatment social function. Notably, the analysis revealed that specific general-cancer symptoms, including appetite loss and dyspnea, were reported in association with OS in seven out of 33 instances, following multivariate analysis. Furthermore, the study highlighted the significance of social eating and problems with swallowing as predictors of OS (≥ 5 times instances) compared to other HNC symptoms-specific outcomes.

Conclusion: This study sheds light on the underexplored role of post-treatment physical function as predictors for OS, complementing the well-discussed pretreatment physical function. It identifies four specific symptoms significantly impacting OS, highlighting the need for effective management strategies.