Management of squamous cell and basal cell carcinomas of the head and neck with perineural invasion

Abstract

Perineural invasion (PNI) occurring in non-melanoma skin cancers (NMSC) is associated with an increased risk of locoregional recurrence and reduced disease-free survival. This necessitates early and accurate diagnosis, appropriate risk-stratification and a clear management strategy. The diagnosis of PNI is based on careful clinical assessment, imaging and histopathology. Surgery, preferably with margin control, and definitive or adjuvant radiotherapy (ART) are established treatment strategies for PNI. Clinical uncertainty remains over the role of ART in incidental PNI. This review synthesises current literature to ascertain which clinicopathological features impart a higher risk to individuals with PNI in NMSC, in order to provide treatment algorithms, including the identification of patient subsets that are most likely to benefit from ART. This includes those with extratumoural PNI, involvement of larger-calibre nerves, tumour invasion beyond dermis, recurrent tumour or diffuse intratumoural spread. Patients with clinical PNI may be optimally managed by a multidisciplinary head and neck cancer service that is best placed to offer skull base surgery and intensity-modulated radiation therapy (IMRT). The management options presented are stratified by histological subtype and a new classification of PNI into low-risk, medium-risk and high-risk groups.

Molecular mechanisms of perineural spread of cutaneous carcinoma: a potential role for receptor tyrosine kinases and other biomarkers

“…(32) Cutaneous SCCHN has a particularly high propensity for PNI, where it is an aggressive feature, portending an increased risk of locoregional recurrence and reduced disease-free survival. (33) In one series, 3-year disease-specific survival for cSCC with and without PNI was 64% and 91%, respectively. (34) Large studies by Goepfert et al (n=967) and Leibovitch et al (n=1177) firmly established the link between PNI and tumour recurrence, distant metastasis and reduced survival.…”

Common dermatology questions and answers about the radiation treatment of skin cancer in the modern era

“…If this is close (eg <2mm) then consider referral especially if there are other relative factors for recurrence eg recurrent lesion, lesion over 4mm thick, over 2cm in diameter, involvement of largercalibre nerves and tumour invasion beyond dermis. 31 c. Clinical PNI means that at presentation PNI symptoms or signs are present. These symptoms are often missed and must be enquired about eg formication, motor loss and/or paraesthesia in the nerve distribution.…”

Carcinoma de células escamosas de piel. Serie de casos

“…Los tumores de bajo grado se resecan con un margen de seguridad de a lo menos 5 mm de diámetro y aquellos de alto grado se resecan con un margen macroscópico sano, mínimo de 1 cm 19 . Se intenta, en la mayoría de los casos, la biopsia contemporánea por congelación de rutina para asegurar la resección completa en la primera intervención ya que la resección incompleta se comporta con una recidiva significativamente mayor 21,22 .…”