Prognostic stratification of patients with AJCC 2018 pStage IVB oral cavity cancer: Should pT4b and pN3 disease be reclassified?

Reliability of Ultrasonographic Assessment of Depth of Invasion and Tumor Thickness in Intraoral Mucosa Lesions: A Preliminary Experience

Introduction: Despite the progress made in multidisciplinary care, there has been little improvement in the oncologic outcomes of oral cavity squamous cell carcinomas (OSCCs). In the latest edition of the TNM staging, "depth of invasion" (DOI) has recently been introduced as one of the criteria for determining the T stage, alongside other factors. DOI is widely recognized as an independent risk factor for nodal metastases and is a crucial consideration in the preoperative staging of OSCCs, along with measurements of tumor thickness (TT). While various diagnostic methods exist for assessing DOI, intraoral ultrasonography (IOUS) has gained popularity for its efficacy in evaluating OSCCs. Methods: This study sought to evaluate the diagnostic accuracy and reliability of ultrahigh-frequency ultrasound (UHFUS) in assessing oral cavity lesions compared to histopathological analysis. Results: The results revealed strong reliability in ultrasonographic measurements (ICC TT: 0.94; ICC DOI: 0.97) and distinct ultrasonographic features specific to different oral pathologies. This highlights the potential of UHFUS as a non-invasive imaging tool for precise diagnostic evaluations. Conclusions: Despite limitations such as a small sample size and focus on specific lesions, these promising results suggest that UHFUS could significantly enhance oral lesion diagnostics. Further research involving larger cohorts is necessary to validate and build upon these initial findings.

The Reliability of Ultrasonographic Assessment of Depth of Invasion: A Systematic Review with Meta-Analysis

Depth of invasion (DOI) has been recognized to be a strong prognosticator for oral squamous cell carcinoma (OSCC). Several diagnostic techniques can be employed for DOI assessment, however intraoral ultrasonography has been increasingly applied for the intraoral evaluation of OSCCs. The aim of the present study is to review the evidence on the application of intraoral ultrasonography to the assessment of DOI in patients affected by OSCC. A systematic electronic and manual literature search was performed, and data from eligible studies were reviewed, selected, and extracted. The studies had to report the correlation between DOI estimated with ultrasonography versus histopathology. A meta-analysis was conducted on the quantitative data available. Sixteen articles were included in the review following the screening of the initial 228 studies retrieved from the literature. The meta-analysis showed a significant correlation between ultrasonographic and histopathologic measurements (p < 0.01). The studies were all at low/moderate risk of bias. Ultrasonography appears a valuable tool for DOI assessment.

Clinical outcomes of patients with pT4a and pT4b oral cavity squamous cell carcinoma who had undergone surgery: Results from a Taiwanese registry-based, nationwide cohort study

OBJECTIVES

While the NCCN guidelines maintain that T4b oral cavity squamous cell carcinoma (OCSCC) should undergo either non-surgical treatments or clinical trials, promising outcomes of T4b OCSCC having surgical excision have been reported. We analyzed and compared the clinical outcomes of Taiwanese patients with pT4a and pT4b OCSCC who had undergone surgical treatment.

METHODS

From 2011 to 2017, a total of 4031 and 355 patients with first primary pT4a and pT4b OCSCC were identified. A propensity score (PS)-matched analysis of patients (n = 351 each) for pT4a and pT4b tumors was also performed.

RESULTS

The 5-year disease-specific and overall survival (DSS/OS) rates were more favorable in patients with pT4a than in those with pT4b OCSCC (64%/55%, p < 0.0001; 55%/43%, p < 0.0001, respectively). Compared with pT4a, those with pT4b tumors had a higher burden of the following risk factors: buccal/retromolar/hard palate subsite, male sex, depth ≥ 10 mm, and positive margins. Before PS matching, multivariable analyses revealed that pT4b tumors (versus pT4a) were an adverse prognosticator for both 5-year DSS and OS (hazard ratios: 1.32 and 1.39, respectively). However, in the PS-matched cohort, no significant differences in 5-year DSS and OS rates were observed between pT4a and pT4b OCSCC (57%/56%, p = 0.4024; 48%/44%, p = 0.1807, respectively) CONCLUSIONS: No significant outcome differences were evident between pT4b and pT4a OCSCC after PS matching. The most plausible hypothesis for the observed survival difference between T4a and T4b tumors is that it was driven by positive margins. We suggest that T4b OCSCC should undergo initial surgical excision if adequate resection is possible.