A Histopathologic Scoring System for Perineural Invasion Correlates With Adverse Outcomes in Patients With Cutaneous...

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Perineural invasion (PNI) is a significant risk factor for adverse outcomes in cutaneous squamous cell carcinoma (cSCC).
• Current staging systems acknowledge PNI but lack detailed criteria for its extent or severity.
• Identifying specific histopathologic features of PNI is crucial for risk stratification in cSCC.

Purpose of the Study:

• To identify histopathologic features of PNI in cSCC associated with adverse outcomes.
• To evaluate the predictive value of these features for recurrence, metastasis, and mortality.
• To develop a more refined method for assessing PNI risk in cSCC.

Main Methods:

• Retrospective cohort study of 45 patients with cSCC and PNI treated surgically.
• Histopathologic analysis of PNI features including nerve diameter, number of nerves affected, depth, location (intra- vs. extratumoral), and pattern (focal vs. circumferential).
• Statistical analysis, including univariate logistic regression, to correlate PNI features with clinical outcomes.

Main Results:

• Median largest affected nerve diameter was 0.13 mm; median number of nerves involved was 4.
• Six patients (13.3%) experienced adverse outcomes, including local recurrence, metastasis, and tumor-related death within 24 months.
• Nerve diameter, number of affected nerves, and a composite PNI score were significantly associated with adverse outcomes (p = .020 for composite score).

Conclusions:

• Histopathologic features of PNI in cSCC are quantifiable.
• A composite PNI score derived from these features is a strong predictor of adverse outcomes.
• This scoring system may improve risk stratification and patient management for cSCC with PNI.