The influence of mild dysplasia at the surgical margin on the prognosis of oral squamous cell carcinoma

Identification of Metabolism-Associated Biomarkers for Early and Precise Diagnosis of Oral Squamous Cell Carcinoma

The 5-year survival rate for oral squamous cell carcinoma (OSCC), one of the most common head and neck cancers, has not improved in the last 20 years. Poor prognosis of OSCC is the result of failure in early and precise diagnosis. Metabolic reprogramming, including the alteration of the uptake and utilisation of glucose, amino acids and lipids, is an important feature of OSCC and can be used to identify its biomarkers for early and precise diagnosis. In this review, we summarise how recent findings of rewired metabolic networks in OSCC have facilitated early and precise diagnosis of OSCC.

Readdressing dysplasia at surgical margins as predictive biomarker of malignant transformation

Clinical, histological and molecular alterations observed at surgical margins could be regarded as predictive markers of malignant transformation. However, there are contrasting views on usefulness of oral epithelial dysplasia (OED) in predicting malignant transformation. In this regard, investigation of OED status at surgical margins could give an interesting perspective to this notion. We searched the reputed databases to retrieve the original research articles wherein the OED status was investigated at the mucosal surgical margins of oral squamous cell carcinoma (OSCC). Intriguingly, in all the studies, number of cases in 'no dysplasia' category was higher than other grades of dysplasia. In our institutional experience of 92 cases of OSCC, 75 (82%) cases showed no evidence of dysplasia at surgical margins. Thus, we conclude that dysplasia status at surgical margins does not support the OED as potential marker of malignant transformation.

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

BACKGROUND

The literature often cites margin status as being free, close or involved by tumor but there is very sparse evidence of the relevance of dysplasia at resection margin. Aims/Objectives: To compare the impact of dysplasia at final resection margin (D-FRM) and other margin statuses on overall survival (OS) and disease free survival (DFS).

METHODS

This is a retrospective review of 1700 treatment naïve oral squamous carcinoma patients who underwent surgery between January 2012 and December 2015. The study arm consisted of patients with dysplasia at final resection margin (D-FRM). Each of these patients were double propensity matched to obtain positive (P-FRM), close (C-FRM) and free final resection margins (F-FRM).

RESULTS

There was no hazard discrimination in survival among the D-FRM and C-FRM (vs F-FRM; p-0.597, HR-1.207 (0.621-2.346) and p-0.075, HR-1.594 (0.947-2.684), respectively). A decreasing survival trend was observed as the grade and number of D-FRM margins increased. Although not significant, the addition of adjuvant therapy for D-FRM showed a trend towards improved survival outcomes compared to C-FRM, especially with chemotherapy. Conclusion and relevance: The presence of D-FRM, irrespective of grade, had a similar impact on survival as C-FRM and underscores the possible need for treatment intensification.

Lugol's Iodine-Enhanced Micro-CT: A Potential 3-D Imaging Method for Detecting Tongue Squamous Cell Carcinoma Specimens in Surgery

Background

A positive surgical margin (PSM) following oral cancer resection results in local recurrence and poor prognosis. Mono-block tumor specimens, especially from the tumor base, are difficult to evaluate. This inaccurate sampling ultimately leads to a false pathological diagnosis. Lugol’s iodine (I₂-IK)-enhanced micro-CT is an emerging method to image tumor specimens. This study explores the feasibility of I₂-IK-enhanced micro-CT to evaluate the surgical margin for tongue squamous cell carcinoma (TSCC) specimens and to further seek optimal staining parameters.

Methods

Rabbit tongue tissues and human TSCC samples were imaged via I₂-IK-enhanced micro-CT. The optimal I₂-IK concentration and staining time were determined before clinical application using tissue shrinkage, micro-CT image quality, and effect on pathological diagnosis as assessment criteria. Next, 6 TSCC specimens were used to verify the process feasibility of surgical margin imaging with the optimal parameters. Finally, the possible reason by which I₂-IK could enhance micro-CT imaging was validated in vitro.

Results

I₂-IK staining influenced specimen shrinkage, micro-CT image quality, and pathological image quality in a concentration- and time-dependent manner. After comprehensively considering these indicators, 3% I₂-IK staining for 48 and 12 h were found to be optimal for rabbit tongue tissues and TSCC samples, respectively. This method could provide a detailed 3-D structure of TSCC samples compared with H&E sections. Moreover, tumor and normal tissues could be differentiated by their glycogen content, which has high affinity with I₂-IK.

Conclusions

I₂-IK-enhanced micro-CT could, thus, indicate the tumor margin and assist pathological sampling in patients with TSCC postoperation.

Margin Practices in Oral Cavity Cancer Resections: Survey of American Head and Neck Society Members

OBJECTIVES/HYPOTHESIS

To investigate the definition of a clear margin and the use of frozen section (FS) among practicing head and neck surgeons in oral cancer management.

STUDY DESIGN

Cross-sectional survey.

METHODS

We designed a survey that was sent to American Head and Neck Society (AHNS) members via an email link.

RESULTS

A total of 185 (13% of 1,392) AHNS members completed our survey. Most surgeons surveyed (96.8%) use FS to supplement oral cavity squamous cell carcinoma resections. Fifty-five percent prefer a specimen-based approach. The majority of respondents believe FS is efficacious in guiding re-resection of positive margins, with 81% considering the new margin to be negative. More than half of respondents defined a distance of >5 mm on microscopic examination as a negative margin.

CONCLUSIONS

To avoid oral cancer resections that result in positive margins on final analysis, and thus the need for additional therapy, most surgeons surveyed use FS. A majority of surveyed surgeons now prefer a specimen-based approach to margin assessment. Although there is a debate on what constitutes a negative margin, most surgeons surveyed believe it to be >5 mm on microscopic examination.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:782-787, 2021.

Real-time surveillance of surgical margins via ICG-based near-infrared fluorescence imaging in patients with OSCC

Background

Local recurrence is the main cause of death among patients with oral squamous cell carcinoma (OSCC). This study assessed near-infrared fluorescence (NIF) imaging and spectroscopy to monitor surgical margins intraoperatively for OSCC.

Methods

Cytological and animal experiments were first performed to confirm the feasibility of monitoring surgical margins with NIF imaging and spectroscopy. Then, 20 patients with OSCC were included in the clinical trials. At 6–8 h after 0.75 mg/kg indocyanine green (ICG) injection, all patients underwent surgery with NIF imaging. During the surgery, both NIF images and quantified fluorescence intensity were acquired to monitor the surgical margins.

Results

In cytological and animal experiments, the results showed it was feasible to monitor surgical margins with NIF imaging and spectroscopy. Fluorescence was detected in primary tumors in all patients. The fluorescence intensities of the tumor, peritumoral, and normal tissues were 398.863 ± 151.47, 278.52 ± 84.89, and 274.5 ± 100.93 arbitrary units (AUs), respectively (P < 0.05). The SBR of tumor to peritumoral tissue and normal tissues was computed to be 1.45 ± 0.36 and 1.56 ± 0.41, respectively. After primary tumor excision, the wounds showed abnormal fluorescence in four patients (4/20), and residual cancer cells were confirmed by pathological examination in two patients (2/20).

Conclusion

These findings confirmed the complementary value of NIF imaging during radical tumor resection of OSCC. Before tumor resection, we could utilize the fluorescence margin produced by ICG NIF imaging to determine the surgical margin. Moreover, after tumor blocks were removed, the status of surgical margin could also be evaluated rapidly by ICG NIF imaging of tumor bed and in vitro specimens.

Amino acids signatures of distance-related surgical margins of oral squamous cell carcinoma

BACKGROUND

Histological assessment of resected margins has some drawbacks. We therefore aimed to identify a panel of metabolic markers for evaluating the surgical margins of oral squamous cell carcinoma during surgery.

METHODS

A total of 28 case of OSCC samples were enrolled in the study. Gas chromatography-mass spectrometry based untargeted metabolic analysis was employed to acquire the metabolic perturbation of the distance-related surgical margins in the development group. The acquired MS data were then subjected to univariate and multivariate analysis by MetaboAnalyst. Ultra-high performance liquid chromatography-tandem mass spectrometerbased targeted metabolomics for quantitative analysis of the validation group was performed to verify the results of the development group. Another 60 OSCC patients with dysplastic surgical margins were used to further validate the results of the development group by immunohistochemical examination of key enzyme expression, and correlate them with clinicopathological parameters and clinical outcomes.

FINDINGS

We finally identified 4 amino acids as negative margin markers, and 6 amino acids as dysplastic margin markers. IHC analysis showed that asparagine synthetase positive expression in dysplastic surgical margins and its higher expression was correlated with tumor recurrence and local relapse-free survival.

INTERPRETATIONS

We developed a panel of metabolic molecular markers to supplement the evaluation of negative and dysplastic margins. FUND: This study was supported by Nanjing Municipal Key Medical Laboratory Constructional Project Funding (Since 2012); Center of Nanjing Clinical Medicine Tumor (Since 2014). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Do dysplastic proximal resection margins predict the risk of anastomotic recurrence and overall survival in patients with esophageal squamous cell carcinoma?

Positive proximal resection margins are strongly associated with anastomotic recurrence in esophageal cancer. However, the prognostic significance of dysplastic proximal resection margins remains unclear. The aim of this study is to investigate whether the dysplastic proximal resection margin can predict anastomotic recurrence and overall survival in patients with esophageal squamous cell carcinoma. Between 2000 and 2014, patients with esophageal squamous cell carcinoma who received a nonpalliative resection and survived the perioperative period were included. Two expert pathologists independently reviewed the proximal resection margin status, which was classified as negative, dysplastic, or positive. The kappa statistic was used to test interobserver reliability. Anastomotic recurrence and overall survival served as the main outcome measures. The study cohort consisted of 469 patients (445 males and 27 females). There was an excellent interobserver agreement for negative (kappa = 0.88), dysplastic (kappa = 0.88), and positive (kappa = 1) proximal resection margins-which were identified in 418 (89.1%), 37 (7.9%), and 14 (3.0%) patients, respectively. After a median follow-up of 21.6 months, 30 (6.4%) patients developed an anastomotic recurrence. Compared with patients with negative proximal resection margins (24/418, 5.7%), the occurrence of anastomotic recurrence was more commonly observed in those with positive proximal resection margins (3/14, 21.4%, P = 0.017) but not in those with dysplastic proximal resection margins (3/37, 8.1%, P = 0.56). Multivariable Cox regression analysis identified positive proximal resection margins (hazard ratio: 5.93, P = 0.010) and advanced clinical stage (hazard ratio: 12.04, P = 0.023) as independent risk factors for anastomotic recurrence. Dysplastic proximal resection margins were not retained in the model as an independent predictor (hazard ratio: 1.38, P = 0.602). The 5-year overall survival rates of patients with negative (38.2%) and dysplastic margins (27.0%) were similar (P = 0.814), and significantly higher than that observed in those with positive proximal resection margins (9.5%, P = 0.015). In conclusion, dysplastic proximal resection margins can be identified in at least 7.9% of patients with esophageal squamous cell carcinoma, but neither they are associated with an increased risk of anastomotic recurrence nor they portend a poor overall survival.

p53-positive expression in dysplastic surgical margins is a predictor of tumor recurrence in patients with early oral squamous cell carcinoma

Purpose

This was a retrospective analysis of the impact of the expression of p53 in the dys-plastic surgical margins of early oral squamous cell carcinoma (OSCC) (pT1-2, N0).

Patients and methods

Seventy-two patients with early oral squamous cell carcinoma (OSCC) were recruited. Margin characteristics were abstracted from the pathology report. Expression of p53 in dysplastic surgical margins was examined with the immunohistochemical method and was correlated with clinicopathological parameters and clinical outcomes.

Results

Patients with moderate/severe dysplasia had poor local relapse-free survival (RFS) compared to those with mild dysplasia. Thirty-two (44.4%) had at least one p53-positive margin, and there was a significant association between the expression of p53 and tumor recurrence (P<0.001). p53-positive expression was correlated with RFS in patients with dysplastic margins, and its expression in moderate/severe dysplastic groups had a worse RFS than mild dysplastic groups. We also found that the grade of the dysplasia margin was not correlated with RFS in p53-negative groups. Multivariable analysis validated p53 expression in dysplastic surgical margins as an independent risk factor for recurrence.

Conclusion

Our results validated that p53 expression was an independent risk factor for early OSCC with dysplastic surgical margins. Additional therapy and close follow-up are needed for these patients.

Relationship of infiltrating intraepithelial T lymphocytes in the diagnosis of oral lichen planus versus oral epithelial dysplasia: a pilot study

OBJECTIVE

The aim of this study was to identify the type and distribution of CD4+ and CD8+ T lymphocytes in oral mucosal specimens to potentially distinguish between underlying alterations or patterns in oral epithelial dysplasia and oral lichen planus.

STUDY DESIGN

This pilot study included 10 archived tissue samples that were received at the University of North Carolina Oral and Maxillofacial Pathology Laboratory and were diagnosed as oral lichen planus and moderate to severe epithelial dysplasia. Dual staining with CD4 and CD8 antibodies was carried out on each case. Slides were scanned in the Aperio ScanScope FL (Leica Biosystems, Wetzlar, Germany) and archived. Histomorphometric analysis was performed to detect inflammatory cells expressing CD4 and CD8 biomarkers in the epithelial and connective tissue regions.

RESULTS

No differences were found in the amount and ratio of CD4+/CD8+ lymphocytes among the 3 groups analyzed; however, the intraepithelial CD8+ lymphocyte distribution was strikingly different between lichen planus and moderate to severe epithelial dysplasia.

CONCLUSIONS

The localization of CD8+ cells can be potentially useful as an adjunctive diagnostic procedure to distinguish oral epithelial dysplasia from other inflammatory entities, such as lichen planus.

Three-dimensional reconstruction with serial whole-mount sections of oral tongue squamous cell carcinoma: A preliminary study

OBJECTIVES

Margin status and invasion pattern are prognostic factors for oral tongue squamous cell carcinoma (OTSCC). Current methods to identify these factors are limited to 2D observation; it is necessary to explore 3D reconstruction with whole-mount sample to improve the accuracy of analysis. This study aimed to study the tissue preparation, section generation, and 3D reconstruction with whole-mount OTSCC specimen.

STUDY DESIGN

Two OTSCC samples were retrieved from Nanjing Stomatological Hospital, Medical School of Nanjing University. One sample was sliced into 3 equal-sized pieces and subjected to different processing schedules to determine the best method. The second sample was processed accordingly. Serial whole-mount sections of the second sample were generated, stained with HE/anticytokine antibody in intersection manner, and scanned into digital images. Digital images were aligned and reconstructed into 3D images with Hetero Genius Medical Image Manager 3D Pathology Add-On [HGMIM3D].

RESULTS

Successful serial whole-mount sections of comparable quality to traditional sections were generated. Three-dimensional images with serial whole-mount sections were successfully generated.

CONCLUSIONS

Whole-mount histopathological 3D reconstruction of OTSCC was successfully generated, providing a solid foundation for comprehensive margin and invasion analysis. Although future study and improvement were needed, whole-mount histopathological 3D reconstruction proved to be a promising method in OTSCC study.