# Oncologic outcomes of microscopic tumor cut through in locally advanced oral squamous cell carcinoma

## TL;DR

This study finds that microscopic tumor cut through (MTCT) is linked to worse outcomes in advanced oral cancer patients, suggesting more aggressive treatment may be needed.

## Contribution

The study identifies MTCT as a significant predictor of poor oncologic outcomes in locally advanced oral squamous cell carcinoma.

## Key findings

- MTCT significantly increases local recurrence risk in oral cancer patients.
- Tumor depth of invasion is the best predictor for compromised frozen sections.
- Treatment intensification is recommended for patients with MTCT.

## Abstract

•MTCT had an impact on local recurrence on univariate (HR = 2.205;) and multivariate (HR = 1.851) analyses.•Disease-specific survival was also affected on univariate (HZ = 1.669).•The best predictor for compromised frozen sections was tumor depth of invasion.•MTCT is an important factor associated with poorer outcome, and treatment intensification should be considered.

MTCT had an impact on local recurrence on univariate (HR = 2.205;) and multivariate (HR = 1.851) analyses.

Disease-specific survival was also affected on univariate (HZ = 1.669).

The best predictor for compromised frozen sections was tumor depth of invasion.

MTCT is an important factor associated with poorer outcome, and treatment intensification should be considered.

This study aims to determine the impact of MTCT on local recurrence and disease-specific survival in patients with locally advanced T3-T4 OCSCC and compare it with other clinicopathological variables.

A retrospective database analysis of patients diagnosed with locally advanced T3-T4 OCSCC surgically treated and submitted to intraoperative frozen section guiding the margin status. Survival was analyzed using the Kaplan-Meier estimator followed by the Cox model for multivariate analysis.

We analyzed 475 patients who met inclusion criteria: MTCT occurred in 29 patients (6.11%) and local recurrence was observed in 131 patients (27.6%). MTCT had an impact on univariate (HR = 2.205; 95% CI 1.243–3.914; p = 0.007) and multivariate (HR = 1.851; 95% CI 1.285–2.666; p = 0.001) analyses. Similar results were found for disease-specific survival: univariate (HZ = 1.669; 95% CI 1.056–2.635; p = 0.028) and multivariate (HZ = 1.307; 95% CI 0.816–2.092; p = 0.265) analyses. A total of 231 patients (48.6%) had died of cancer by the end of follow-up. The best predictor for compromised frozen sections was tumor depth of invasion.

Even after negative final margins, MTCT is an important factor associated with poorer outcome, and treatment intensification should be considered in these patients.

Level III.