Histopathological invasion patterns and prognosis in Oral Squamous Cell Carcinoma: A retrospective analysis of 560 cases.

Background: Oral Squamous Cell Carcinoma (OSCC) remains a global health issue. Accurate histopathological assessment is vital for improving treatment outcomes. This study explores the impact of perineural, lymphatic, and vascular infiltration (Pn1, L1, V1) on OSCC progression, survival, and recurrence.

Methods: This retrospective study included 560 patients with primary OSCC who underwent curative surgical resection between 2012 and 2023. Data analyzed included demographics, tumor staging, histopathological features, treatment, and follow-up outcomes.

Results: A total of 322 males and 238 females with a mean age of 63.8 years were included. L1 was observed in 40 cases (7.1 %), Pn1 in 53 cases (9.5 %), and V1 in 4 cases (0.7 %). The mean follow-up was 29.7 months, with 3-y ear Overall Survival (OS) at 75.2 % and Recurrence-Free Survival (RFS) at 66.0 %. Multivariate logistic regression showed that contralateral lymph node metastases (CLNM) and ExtraCapsular Extension (ECE) were linked to L1 (OR: 7.83, OR: 2.52), while advanced disease and distant metastasis were strongly associated with Pn1 (OR: 12.70, OR: 6.27). Cox regression analysis revealed CLNM, ECE, and L1 were associated with reduced OS (HR: 2.32, HR: 1.82, HR: 1.90), and CLNM, ECE, L1, and poor differentiation (G3) were associated with reduced RFS (HR: 1.84, HR: 1.80, HR: 2.51, HR: 1.75). CLNM and Pn1 were strong predictors of reduced Distant Metastasis-Free Survival (DMFS).

Conclusion: L1 and Pn1 were associated with worse prognoses in OSCC, affecting OS, RFS, and DMFS. Research is required to clarify their roles, and including these factors in OSCC staging may improve treatment outcomes.