Frailty and Recovery Following Free Flap Reconstruction in Head and Neck Cancer: A Systematic Review.

OBJECTIVE: To review the impact of frailty on various outcomes in geriatric head and neck cancer (HNC) patients undergoing microvascular free flap reconstruction (MFFR). DATA SOURCES: MEDLINE, Embase, and World of Science. REVIEW METHODS: Following PRISMA guidelines, two independent reviewers performed a systematic review of MEDLINE, Embase, and World of Science databases from inception to January 10, 2025. Peer-reviewed primary literature, excluding case reports, that assessed outcomes in patients with HNC undergoing MFFR with a validated frailty index were included for analysis. Study quality and risk of bias were assessed using the Newcastle-Ottawa Scale (NOS). Data regarding surgical and medical complications, hospital course, and functional outcomes were synthesized. RESULTS: Eleven studies were included for review, six of which were from the United States. Eight were of "Good" quality per the NOS. Utilized frailty measures included the 5-factor Modified Frailty Index (5-mFI), 11-mFI, Geriatric 8, Risk Classification System, Prognostic Nutritional Index, Risk Assessment Index, and Cervical Paraspinal Skeletal Muscle Index. Frailty was consistently associated with increased medical complications, longer hospital length of stay, and higher likelihood of non-home discharge. Frailty predicted impaired swallowing recovery and a longer need for enteral nutrition but associations between frailty and surgical complications or short-term mortality were inconsistent. Studies incorporating nutritional or sarcopenia-based measures outperformed frailty indices alone in predicting postoperative complications. CONCLUSION: In patients undergoing MFFR, frailty was consistently associated with medical morbidity, prolonged hospitalization, and worse functional outcomes. Frailty assessment tools may have an important role in preoperative patient counseling and anticipating discharge needs.