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Updated: Aug 6, 2026

Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
Diagnostic Delay of Unilateral Facial Paralysis Caused by Occult Malignancy: A Scoping Review
Kai C Kokesh1, Gabrielle Cahill2, Irene Kim2
1Department of Otolaryngology-Head and Neck Surgery, Division of Facial Plastic and Reconstructive Surgery, University of Washington School of Medicine, Seattle, Washington, USA.
Objective:
This scoping review aims to evaluate the clinical characteristics, diagnostic challenges, and histopathology of unilateral facial paralysis due to occult malignancy.
Data Sources:
A systematic search of EBSCO and Embase databases was performed.
Review Methods:
Studies reporting patients with unilateral facial paralysis initially associated with negative work-up or diagnostic delay and ultimately attributed to biopsy-proven malignancy of the facial nerve were included. Two reviewers independently screened titles, abstracts, and full texts, with disagreements resolved by a third reviewer. Clinical features, imaging study quantity and type, diagnostic delay, method of tissue acquisition, malignancy type, and cancer history were retrieved.
Results:
Twenty-seven studies, comprising 66 patients, met inclusion criteria. All studies were case series or case reports. The mean patient age was 62 years (range, 33-89), and 76% were male. All patients presented with progressive facial paralysis. Trigeminal symptoms were reported in 35 cases (53%), and additional cranial nerve involvement in 15 cases (22%). The mean diagnostic delay was 21 months (range, 1-180). MRI was the most common imaging modality (54%). Surgical biopsy was utilized for diagnosis in 76% of patients. Squamous cell carcinoma was the most common malignancy (38%), frequently associated with prior regional cutaneous disease.
Conclusion:
Occult malignancy is a rare but clinically significant cause of unilateral facial paralysis and is frequently associated with prolonged diagnostic delay. Progressive paralysis, lack of recovery, trigeminal symptoms, additional cranial neuropathies, or a history of skin cancer should prompt repeat imaging and consideration of biopsy, even in the setting of negative initial imaging.
Level Of Evidence:
N/A.