Incidence and impact of dysplasia at final resection margins in cancers of the oral cavity

Prognostic significance of dysplasia associated with oral squamous cell carcinoma in patients undergoing surgery with curative intent

The aim of this study was to evaluate the prognostic significance of dysplasia in patients undergoing primary surgery with curative intent in the treatment of oral squamous cell carcinoma (OSCC). This study specifically aimed to demonstrate the effect of dysplasia on local recurrence, disease specific survival (DSS) and overall survival (OS). Data collection for 833 patients with OSCC undergoing treatment for curative intent was undertaken retrospectively for the period of February 2006 to May 2020. Analysis of any association between known clinicopathological prognostic categorical variables with respect to dysplasia was undertaken using the chi squared test. A Kaplan-Meier analysis was performed to demonstrate the impact of dysplasia on DSS and OS, and Cox's proportional-hazards model deployed to obtain hazard ratios associated with dysplasia and the outcomes of interest. Dysplasia was statistically significant in predicting disease specific and overall survival in patients undergoing primary surgery for OSCC (DSS p<0.001, HR 0.577; 95%CI 0.428 to 0.777), OS p<0.001 HR 0.691; 95%CI 0.562 to 0.850) with the absence of dysplasia predicting poorer outcomes. The absence of dysplasia correlated with pathological higher T and N stage, increased categorised depth of tumour invasion, non-cohesive invasive front, lymphovascular invasion, perineural invasion, extranodal extension and increased modified Glasgow Prognostic Score. No significant prognostic relationship was attributable to the presence of dysplasia at a surgical margin. The absence of dysplasia appeared to be a significant independent prognostic indicator for patients with OSCC. The presence or absence of dysplasia may provide a heuristic means of stratifying OSCC primary lesions in terms of disease hostility.

Risk Factors of Microscopically Tumor-Free Surgical Margins for Recurrence and Survival of Oral Squamous Cell Carcinoma Patients

Objectives

The concept of adequate surgical margins remains controversial in oral squamous cell carcinoma (OSCC) surgery. This study aimed to identify surgical margin-related indicators that might impact recurrence and survival of OSCC patients.

Materials and Methods

Histopathological examination was performed using hematoxylin-eosin-stained surgical margin tissue sections in 235 OSCC patients. Axin2 and Snail expression at the surgical margin was detected by immunohistochemistry. The impact of the Axin2-Snail cascade on tumorigenesis of the immortalized human oral keratinocyte (IHOK) line was investigated in vivo.

Results

The width and dysplasia of surgical margins were not significantly associated with the outcome of OSCC patients. In a multivariate analysis using variable clinicopathologic factors and with Axin2 and Snail expression as cofactors, higher age (hazard ratio [HR]:1.050; P=0.047), Axin2 (HR:6.883; P=0.014), and Snail abundance (HR:5.663; P=0.009) had independent impacts on worsened overall survival. Similarly, lesion site in retromolar trigone (HR:4.077; P=0.010), upper (HR:4.332; P=0.005) and lower gingiva (HR:3.545; P=0.012), presence of extranodal extension (HR:9.967; P<0.001), perineural invasion (HR:3.627; P=0.024), and Snail abundance (HR:3.587; P<0.001) had independent impacts on worsened recurrence-free survival. Furthermore, Axin2 knockdown induced decreased Snail expression and attenuated tumorigenesis in the IHOK line.

Conclusion

Histopathological examination of surgical margins may not be reliable to predict OSCC patient outcome. Molecular analysis may provide a more accurate risk assessment of surgical margins in OSCC. In particular, Axin2 and Snail are potential predictive biomarkers for the risk assessment of surgical margins in OSCC.

Impact of Close Margins in Head and Neck Mucosal Squamous Cell Carcinoma: A Systematic Review

OBJECTIVES/HYPOTHESIS

The aim of the study is to investigate whether close surgical margins impact oncologic outcomes compared to clear or involved surgical margins. We hypothesize that close surgical margins portend worse outcomes compared with clear margins, but improved outcomes compared with involved margins.

STUDY DESIGN

Systematic review.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement standards, a systematic search was conducted for studies that reported oncologic outcomes following excision of primary mucosal head and neck squamous cell carcinoma (HNSCC). A meta-analysis was then performed, comparing local recurrence (LR), locoregional recurrence (LRR), and overall survival (OS) in patients with clear, close, and involved margins.

RESULTS

Twenty-six studies met the inclusion criteria, totaling 8,435 patients. About 96% of our included cases involved the oral cavity, 2% involved the oropharynx, and 2% other. Also, 68% of cases were T1/T2 and 32% were T3/T4. On meta-analysis, clear margins were associated with lower incidence of 5-year LR relative risk (RR) 0.50, 95% confidence interval [CI] 0.38-0.65) and higher 5-year OS (RR 1.22, 1.11-1.35), when compared with close margins. Involved margins had higher incidence of 5-year LR (RR 1.75, 1.16-2.64), higher incidence of LRR at last follow-up (RR 1.66, 1.37-2.00), and no difference in 5-year OS (RR 0.82, 0.60-1.11), when compared with close margins.

CONCLUSIONS

There is a stepwise improvement in oncologic outcomes as surgical margin categorically improves from involved to close to clear. Patients with close margins therefore may benefit from adjuvant therapy. Further research is required to investigate whether these findings are seen in non-oral cavity cases because they were underrepresented in this analysis. Laryngoscope, 2021.