title: Perineural invasion and spread in head and neck cancer.
abstract: Perineural involvement is a well-recognized clinicopathologic entity found in head and neck (H&N) cancers, including mucosal epithelial carcinomas and salivary gland malignancies. Perineural disease remains a diagnostic, prognostic and therapeutic challenge for the multidisciplinary H&N oncology team. Nerves are important routes of tumor spread in H&N malignancies, yet the biology and prognostic implications of perineural tumor growth are not fully understood. On balance, the available evidence suggests that it is associated with an increased risk of locoregional recurrence but the impact on survival remains uncertain. Perineural involvement has implications for locoregional disease diagnosis and management. MRI is the best imaging modality to detect tumor extent. Advanced radiotherapy technologies such as intensity-modulated radiation therapy and image-guided radiation therapy have the potential for more accurate targeting and treatment of anatomically complex patterns of disease spread. This review is limited to nondermatologic H&N cancers.
authors.affiliation: Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, 610 University Avenue, Toronto, ON, M5G 2M9, Canada.
authors.forename: Meredith
authors.initials: M
authors.lastname: Johnston
authors.forename: Eugene
authors.initials: E
authors.lastname: Yu
authors.forename: John
authors.initials: J
authors.lastname: Kim
mesh_terms: D002277:Carcinoma / Q000556:secondary*; D019468:Disease Management; D006258:Head and Neck Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000532:radiotherapy; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009092:Mucous Membrane / Q000294:innervation / Q000473:pathology; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D009423:Nervous System Neoplasms / Q000556:secondary*; D010256:Paranasal Sinuses / Q000294:innervation / Q000473:pathology; D010525:Peripheral Nerves / Q000473:pathology*; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D013284:Stomatognathic System / Q000294:innervation / Q000473:pathology; D013679:Technology, Radiologic