Elective neck dissection improves the survival of patients with T2N0M0 oral squamous cell carcinoma: a study of the SEER database

The significance of elective neck dissection for patients with T2N0M0 OSCC at different ages

BACKGROUND

The aim of this study was to determine the significance of elective neck dissection (END) for patients of different ages with T2N0M0 oral squamous cell carcinoma (OSCC) and sought to analyze the reasons behind it and its value for clinical guidance.

METHODS

This study enrolled 391 patients with T2N0M0 OSCC who were surgically treated in our hospital and were divided into young-, moderate-, and advanced-age groups according to our previous study. The Chi-square test and Kaplan-Meier analysis were performed for statistical analysis.

RESULTS

Compared with moderate- and advanced-age patients, young patients with T2N0M0 OSCC had higher lymph node metastasis rates and lymph node ratios. Therefore, END significantly improved the recurrence (p = 0.001) and survival (p = 0.001) for young patients, but not for moderate-age patients. Advanced-age patients even benefit from watchful waiting. END significantly improved recurrence and survival in young patients with smoking or alcohol consumption habits.

CONCLUSIONS

END improved the prognosis of young patients, and it was related to their higher metastasis rate. However, advanced-age patients benefited from the wait-and-see policy. END is essential for the young patients with smoking or drinking habit, it is also highly recommended for nonsmokers and nondrinkers.

Prognostic risk factors of buccal squamous cell carcinoma: A case-control study

OBJECTIVES

To describe the clinicopathologic presentation of buccal squamous cell carcinoma and identify risks factors for recurrence and overall survival.

METHODS

This is a retrospective case-control study of patients with oral cavity squamous cell carcinoma (OCSCC) treated at a single tertiary care center between 2010 and 2022. All patients with buccal subsite OCSCC treated during this time frame were included and paired with a randomly selected age and gender matched patient with non-buccal OCSCC. Relevant data was collected via chart review.

RESULTS

Seventy-seven patients with buccal SCC were matched with 77 non-buccal OCSCC controls. The median follow-up time was 27 months (IQR 14-61). Median age was 67 years (IQR 57-75) and 53% of the cohort was female. Twenty (26%) buccal SCC patients experienced a recurrence versus 19 (25%) in the controls. Age ≥65-years-old increased odds of all-cause mortality in the buccal SCC group, but not in the control group. Perineural invasion and positive margins increased odds of recurrence in the buccal group only. Overall survival and progression-free survival did not differ between the groups, despite a greater number of T2 buccal tumors and T1 non-buccal tumors.

CONCLUSIONS

Buccal SCC presents at a higher T stage than other oral cavity SCC subsite and may exhibit variance in the pathologic risk factors that predict poor outcomes versus non-buccal OCSCC. Despite these relatively minor differences, however, oncologic outcomes between these groups were similar.

Do patients with cN0 oral squamous cell carcinoma benefit from elective neck dissection? A large-scale population-based study

BACKGROUND

The neck management of clinical-nodal negative (cN0) oral squamous cell carcinoma (OSCC) remains controversial. Elective neck dissection (END) and observation are the main strategies, but it is still not clear who could benefit the most from END. The purpose of this study was to clarify the potential clinical factors that affect the therapeutic value of END and to explore the actual characteristics associated with benefit from END.

METHODS

Patients with cN0 OSCC were identified in the SEER database from 2000 to 2019. 5-year Overall survival (OS) and disease-specific survival (DSS) were analyzed using the Kaplan‒Meier method, and the hazard ratios (HRs) for survival were estimated using the Cox regression model. Multiple subgroup analyses of DSS and OS among different factors, comparing END and No END, were performed.

RESULTS

A total of 17,019 patients with cN0 OSCC were included. The basic survival analysis and Cox regression model showed that END increased the probability of 5-year DSS and OS and was an independent prognostic factor. However, among patients who underwent only primary tumor surgery, no significant differences were found between the END and No END groups in 5-year DSS (P = 0. 585) and OS (P = 0.465). Further subgroup analysis showed that primary sites and T stage, but not other factors, might influence the benefit of END. Significant differences were found for T1 (P < 0.001 for OS) and T2 (P = 0.001 for DSS and < 0.001 for OS) tongue squamous cell carcinoma (TSCC) but not for other primary tumor sites.

CONCLUSION

This large-scale retrospective population-based cohort study suggests that not all patients with cN0 OSCC could benefit from END. Patients with cN0 TSCC are recommended to undergo END, especially with early-stage tumors.

Is elective neck dissection justified in cT2N0M0 oral cavity cancer defined according to the AJCC eighth edition staging system?

BACKGROUND

The current NCCN guidelines recommend considering elective neck dissection (END) for early-stage oral cavity squamous cell carcinoma (OCSCC) with a depth of invasion (DOI) exceeding 3 mm. However, this DOI threshold, determined by evaluating the occult lymph node metastatic rate, lacks robust supporting evidence regarding its impact on patient outcomes. In this nationwide study, we sought to explore the specific indications for END in patients diagnosed with OCSCC at stage cT2N0M0, as defined by the AJCC Eighth Edition staging criteria.

METHODS

We examined 4723 patients with cT2N0M0 OCSCC, of which 3744 underwent END and 979 were monitored through neck observation (NO).

RESULTS

Patients who underwent END had better 5-year outcomes compared to those in the NO group. The END group had higher rates of neck control (95% vs. 84%, p < 0.0001), disease-specific survival (DSS; 87% vs. 84%, p = 0.0259), and overall survival (OS; 79% vs. 73%, p = 0.0002). Multivariable analysis identified NO, DOI ≥5.0 mm, and moderate-to-poor tumor differentiation as independent risk factors for 5-year neck control, DSS, and OS. Based on these prognostic variables, three distinct outcome subgroups were identified within the NO group. These included a low-risk subgroup (DOI <5 mm plus well-differentiated tumor), an intermediate-risk subgroup (DOI ≥5.0 mm or moderately differentiated tumor), and a high-risk subgroup (poorly differentiated tumor or DOI ≥5.0 mm plus moderately differentiated tumor). Notably, the 5-year survival outcomes (neck control/DSS/OS) for the low-risk subgroup within the NO group (97%/95%/85%, n = 251) were not inferior to those of the END group (95%/87%/79%).

CONCLUSIONS

By implementing risk stratification within the NO group, we found that 26% (251/979) of low-risk patients achieved outcomes similar to those in the END group. Therefore, when making decisions regarding the implementation of END in patients with cT2N0M0 OCSCC, factors such as DOI and tumor differentiation should be taken into account.

Diagnostic accuracy of contrast-enhanced computed tomography in assessing cervical lymph node status in patients with oral squamous cell carcinoma

OBJECTIVE

Accurate preoperative prediction of lymph node (LN) status plays a pivotal role in determining the extension of neck dissection (ND) required for patients with oral squamous cell carcinoma (OSCC). This study aims to evaluate the diagnostic accuracy of contrast-enhanced computed tomography (CT) in detecting LN metastases (LNMs) and to explore clinicopathological factors associated with its reliability.

METHODS

Data from 239 patients with primary OSCC who underwent preoperative CT and subsequent radical surgery involving ND were retrospectively reviewed. Suspicious LNs were categorized into three groups: accentuated (< 10 mm), enlarged (≥ 10 mm), and melted. Statistical analysis encompassing correlation and comparative analysis, and determination of sensitivity, specificity, PPV, and NPV were performed.

RESULTS

Overall, sensitivity was significantly higher in the accentuated LNs group (83.54%) compared to the melted LNs group (39.24%, p < 0.05, t test). Conversely, specificity was significantly higher in the melted LNs group (98.19%) compared to the accentuated LNs group (55.15%, p < 0.05, t test). Accentuated LNs exhibited a false negative rate of 13.00%. False positive rates were 51.80%, 30.26% and 8.82%, respectively. Diagnostic accuracy for detecting LNMs in level IIa and IIb exceeded that of level III. Patients with solely accentuated LNs were more likely to have a small, well-differentiated tumor. However, no distinctions emerged in terms of the occurrence of T4 tumors among the three groups.

CONCLUSION

CT proves sufficient to predict LNMs in patients with OSCC. Looking ahead, the potential integration of artificial intelligence and deep learning holds promise to further enhance the reliability of CT in LNMs detection. However, this prospect necessitates further investigation.

Nodal Metastasis in Surgically Treated Oral Cavity Squamous Cell Carcinoma

INTRODUCTION

Management of the neck in oral cavity squamous cell carcinoma (OCSCC) is essential to oncologic control and survival. The rates of lymph node metastasis (LNM) vary based on oral cavity tumor site and stage and influence treatment decisions. The aim of this paper was to describe clinical LNM for different tumor subsites and stages of surgically managed OCSCC.

METHODS

We conducted a retrospective analysis of 25,846 surgically managed OCSCC patients from the National Cancer Database (NCDB) stratified by tumor subsite and clinical T-stage. For cN + patients, rates of pathologic LNM and absence of pathologic LNM were determined. For cN0 patients, outcomes included the rates of elective neck dissection (END) and occult LNM and predictors of occult LNM determined by a multivariable logistic regression model.

RESULTS

A total of 25,846 patients (59.1% male, mean age 61.9 years) met inclusion criteria with primary tumor sites including oral tongue (50.8%), floor of mouth (21.2%), lower alveolus (7.6%), buccal mucosa (6.7%), retromolar area (4.9%), upper alveolus (3.6%), hard palate (2.7%), and mucosal lip (2.5%). Among all sites, clinical N+ rates increased with T-stage (8.9% T1, 28.0% T2, 51.6% T3, 52.5% T4); these trends were preserved across subsites. Among patients with cN + disease, the overall rate of concordant positive pathologic LNM was 80.1% and the rate of discordant negative pathologic LNM was 19.6%, which varied based on tumor site and stage. In the overall cohort of cN0 patients, 59.9% received END, and the percentage of patients receiving END increased with higher tumor stage. Occult LNM among those cN0 was found in 25.1% of END cases, with the highest rates in retromolar (28.8%) and oral tongue (27.5%) tumors. Multivariable regression demonstrated significantly increased rates of occult LNM for higher T stage (T2 OR: 2.1 [1.9-2.4]; T3 OR: 3.0 [2.5-3.7]; T4 OR: 2.7 [2.2-3.2]), positive margins (OR: 1.4 [1.2-1.7]), and positive lymphovascular invasion (OR: 5.1 [4.4-5.8]).

CONCLUSIONS

Management of the neck in OCSCC should be tailored based on primary tumor factors and considered for early-stage tumors.

miR-99a-5p as a biomarker for lymph node metastasis prediction in oral squamous cell carcinoma patients

BACKGROUND

Metastatic lymph node involvement influences therapy decisions and serves as a prognostic indicator in oral squamous cell carcinoma (OSCC). However, many early-stage patients with clinically negative lymph nodes exhibit no metastasis upon surgical staging. This study aimed to identify differentially expressed miRNAs capable of distinguishing pathologically positive (pN+) from negative (pN0) nodes in OSCC patients without clinical evidence of lymph node metastases (cN0).

METHODS

Expression levels of 798 miRNAs were assessed in tumor samples from 10 pN+ and 10 pN0 patients using the Nanostring nCounter platform. Validation was performed in an independent cohort of 15 pN+ and 24 pN0 patients through RT-qPCR.

RESULTS

Eight miRNAs exhibited differential expression between pN0 and pN+ patients. Notably, hsa-miR-99a-5p demonstrated high sensitivity and specificity in predicting patients at higher risk of positive lymph nodes.

CONCLUSIONS

These findings highlight hsa-miR-99a-5p as a potential biomarker for detecting lymph node metastasis in primary OSCC tumors.

Rac1 activation in oral squamous cell carcinoma as a predictive factor associated with lymph node metastasis

OBJECTIVES

Secondary lymph node metastasis (SLNM) indicates a poor prognosis, and limiting it can improve the survival rate in early-stage tongue squamous cell carcinoma (TSCC). Many factors have been identified as predictors of SLNM; however, there is no unified view. Ras-related C3 botulinum toxin substrate 1 (Rac1) was found to be a promoter of the epithelial-mesenchymal transition (EMT) and is also attracting attention as a new therapeutic target. This study aims to investigate the role of Rac1 in metastasis and its relationship with pathological findings in early-stage TSCC.

MATERIALS AND METHODS

Rac1 expression levels of 69 cases of stage I/II TSCC specimens and their association with clinicopathological characteristics were evaluated by immunohistochemical staining. The role of Rac1 in oral squamous cell carcinoma (OSCC) was examined after Rac1 in OSCC cell lines was silenced in vitro.

RESULTS

High Rac1 expression was significantly associated with the depth of invasion (DOI), tumor budding (TB), vascular invasion, and SLNM (p < 0.05). Univariate analyses revealed that Rac1 expression, DOI, and TB were factors significantly associated with SLNM (p < 0.05). Moreover, our multivariate analysis suggested that Rac1 expression was the only independent determinant of SLNM. An in vitro study revealed that Rac1 downregulation tended to decrease cell migration and proliferation.

CONCLUSION

Rac1 was suggested to be an important factor in the metastasis of OSCC, and it could be useful as a predictor of SLNM.