Perineural invasion and perineural spread in periocular squamous cell carcinoma

Abstract

Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) of the periocular region is a prognostic marker of adverse tumour outcomes. PNI carries a well-established risk of tumour recurrence, regional metastasis and higher likelihood of mortality. This review will explore and stratify the risks conferred by histological PNI parameters. The radiological features of perineural spread (PNS) and the imaging sequences that delineate these findings will also be highlighted. Surgical excision with en face margin control is the preferred technique for achieving histological clearance. Adjuvant radiotherapy improves treatment outcomes in the setting of concomitant high-risk features. For locally advanced or metastatic cutaneous SCC, immunotherapy represents a novel treatment alternative. This review will provide an algorithm for the diagnosis and management of periocular SCC with PNI and PNS.

Periocular Malignancies and Postoperative Eyelid Reconstruction

“…PNI occurs in periocular SCC with a rate of 4.3% to 14.4%. 7,18,22,24,25 It has a known increased risk of regional metastasis, tumor recurrence, and death. When dealing with periocular SCC, clinicians should always be on the lookout for PNI, and these patients should be continuously monitored.…”

“…Inherent risk factors for developing skin cancer include actinic damage, primary squamous cell carcinoma, pre-existing chronic skin injuries, such as ulcers, burns, sinus tracts, vaccination scars, and chronic skin illnesses 16,19,20 . SCC is distinguished by its propensity for perineural and vascular invasion, deep subclinical extension, and potential for fast growth 22 . SCC is more likely than BCC to invade the orbit, and it usually spreads through lymphatic and hematologic routes to nearby lymph nodes and distant areas.…”

“…Perineural invasion (PNI) describes tumor growth near or inside a nerve. PNI occurs in periocular SCC with a rate of 4.3% to 14.4% 7,18,22,24,25 . It has a known increased risk of regional metastasis, tumor recurrence, and death.…”

“…16,19,20 SCC is distinguished by its propensity for perineural and vascular invasion, deep subclinical extension, and potential for fast growth. 22 SCC is more likely than BCC to invade the orbit, and it usually spreads through lymphatic and hematologic routes to nearby lymph nodes and distant areas. When cutaneous squamous cell carcinoma has local or distant metastases, the prognosis is poor and may require radiation or chemotherapy in addition to surgical excision.…”

Transorbital Endoscopic Approach to the Foramen Rotundum for Infraorbital Nerve Stripping

“…PNS refers to clinically manifest or radiological involvement of perineural infiltration and is a common manifestation of periocular squamous cell carcinoma. 1,2 Panizza et al proposed anatomical boundaries that define the zonal extent of PNS with implications for management. 3,4 Zone 1 PNS of the maxillary nerve refers to disease extending up to the external aperture of the FR, and the recommended treatment for zone 1 PNS is excision of the entire distal length of the nerve up to the FR.…”