Prediction of nodal disease in oral squamous cell carcinoma of the tongue: histopathological risk assessment with the focus on depth of invasion.

OBJECTIVE

Cervical lymph node metastasis (CLNM) is one of the most relevant influencing factors for the oncological outcome of patients with oral squamous cell carcinoma (OSCC). Several studies showed that the tumors depth of invasion (DOI) influences the risk for CLNM, however varying across the oral subsites. The aim of this study is to investigate the role of DOI and other risk factors in OSCC of the tongue in relation to the occurrence of occult CLNM.

MATERIALS AND

METHODS

In this retrospective study, n = 139 patients with primary OSCC of the tongue, treated by complete surgical resection (R0) with curative intention between 2013 and 2021, were included. For data analysis, epidemiologic data as well as preoperative tumor staging, surgical therapy including neck management, histopathological tumor data and follow-up were considered. Uni- and multivariate logistic regression were used to determine association between histopathological risk factors and the occurrence of occult CLNM.

RESULTS

The rate of occult cervical metastasis was 19.4%. T-staging, cervical nodal disease (pN+) and lymphatic invasion were significantly associated with reduced OS and RFS. While DOI had no relevant influence on the OS and RFS (p = 0.88 and p = 0.91 respectively), there was significant correlation between DOI and the occurrence of occult CLNM (OR: 1.17, 95%CI: 1.05-1.30; p < 0.01). The optimal cutoff in predicting occult CLNM was 6 mm (Sensitivity: 84.2%, Specificity: 73.5%, AUC: 0.75).

CONCLUSIONS

The DOI is a helpful risk parameter to predict the occurrence of occult nodal disease in OSCC of the tongue. Given the critical decision cutoff between 2 and 4 mm DOI for performing elective neck dissection in the current guidelines, our data suggests that in these cases, surgical de-escalation could be feasible with close follow-up.

CLINICAL RELEVANCE: This study highlights the relevance of DOI as a risk parameter in the prediction of CLNM with the aim to specify the individual patient risk and to deescalate surgical therapy in order to decrease comorbidities while improving the oncological prognosis.