Primary Management of Operable Locally Advanced Oral Cavity Squamous Cell Carcinoma: Current Concepts and Strategies

INTRODUCTION

Locally advanced oral cavity carcinoma (LAOCSCC) is primarily treated with surgery followed by radiotherapy with or without chemotherapy.

METHODS

A review of literature using PubMED was performed for studies reporting the management of LAOCSCC. Based on the reviewed literature and opinions of experts in the field, recommendations were made.

RESULTS

Studies have shown that outcomes following resection of T4a and infranotch (inferior to mandibular notch) T4b are comparable. We discuss the concept of compartmental resection of LAOCSCC and issues concerning the management of the neck. Further, patients who refuse or are unable to undergo surgery can be treated with chemoradiotherapy with uncertain outcomes. The role of neoadjuvant chemotherapy has shown promise for organ (mandibular) preservation in a select subset of patients.

CONCLUSION

The management strategy for LAOCSCC should be determined in a multidisciplinary setting with emphasis on tumor control, functional preservation, and quality of life of the patient.

Margin to depth of invasion ratio as an indicator for stratifying close margins in early-stage oral squamous cell carcinoma

OBJECTIVES

In early-stage oral squamous cell carcinoma (OSCC) patients, whether the margin-to-depth-of-invasion ratio (MDR) can assist in stratifying the prognosis remains unclear.

METHODS

Patients diagnosed with early stage OSCC at National Taiwan University Hospital between January 2007 and December 2021 were reviewed. Patients with margin > 1 mm were classified into two groups: MDR < 0.5 and MDR ≥ 0.5.

RESULTS

We analyzed 911 pT1-2N0M0 OSCC patients, 723 (79.36 %) with MDR ≥ 0.5 and 188 (20.64 %) with MDR < 0.5. Patients in the MDR < 0.5 group displayed a significantly higher local recurrence rate (odds ratio 2.81, p = 0.002) compared with MDR ≥ 0.5 group. The 5-year disease-free survival were 80.8 % for clear margin, 76.3 % for close margin (MDR ≥ 0.5), and 65.2 % for close margin (MDR < 0.5). The overall survival displayed a similar pattern, with 5-year rates of 88.3 % for clear margin, 86.8 % for close margin (MDR ≥ 0.5), and 75.0 % for close margin (MDR < 0.5). There were no significant overall survival differences between the two MDR ≥ 0.5 groups, but both were significantly superior to patients with MDR < 0.5 (p = 0.001; p = 0.01). After multivariant cox analysis, MDR < 0.5 was a significant risk factor for disease-free survival (p < 0.001).

CONCLUSION

For early stage OSCC patients without positive margin (≦1mm), the survival outcome between MDR ≥ 0.5 group and MDR < 0.5 group was significantly different. The MDR < 0.5 group had significantly higher risk of local recurrence that may warrant adjuvant treatment.

The modified Polsby-Popper score, a novel quantitative histomorphological biomarker and its potential to predict lymph node positivity and cancer-specific survival in oral tongue squamous cell carcinoma

BACKGROUND

The significance of different histological spreading patterns of tumor tissue in oral tongue squamous cell carcinoma (TSCC) is well known. Our aim was to construct a numeric parameter on a continuous scale, that is, the modified Polsby-Popper (MPP) score, to describe the aggressiveness of tumor growth and infiltration, with the potential to analyze hematoxylin and eosin-stained whole slide images (WSIs) in an automated manner. We investigated the application of the MPP score in predicting survival and cervical lymph node metastases as well as in determining patients at risk in the context of different surgical margin scenarios.

METHODS

We developed a semiautomated image analysis pipeline to detect areas belonging to the tumor tissue compartment. Perimeter and area measurements of all detected tissue regions were derived, and a specific mathematical formula was applied to reflect the perimeter/area ratio in a comparable, observer-independent manner across digitized WSIs. We demonstrated the plausibility of the MPP score by correlating it with well-established clinicopathologic parameters. We then performed survival analysis to assess the relevance of the MPP score, with an emphasis on different surgical margin scenarios. Machine learning models were developed to assess the relevance of the MPP score in predicting survival and occult cervical nodal metastases.

RESULTS

The MPP score was associated with unfavorable tumor growth and infiltration patterns, the presence of lymph node metastases, the extracapsular spread of tumor cells, and higher tumor thickness. Higher MPP scores were associated with worse overall survival (OS) and tongue carcinoma-specific survival (TCSS), both when assessing all pT-categories and pT1-pT2 categories only; moreover, higher MPP scores were associated with a significantly worse TCSS in cases where a cancer-free surgical margin of <5 mm could be achieved on the main surgical specimen. This discriminatory capacity remained constant when examining pT1-pT2 categories only. Importantly, the MPP score could successfully define cases at risk in terms of metastatic disease in pT1-pT2 cancer where tumor thickness failed to exhibit a significant predictive value. Machine learning (ML) models incorporating the MPP score could predict the 5-year TCSS efficiently. Furthermore, we demonstrated that machine learning models that predict occult cervical lymph node involvement can benefit from including the MPP score.

CONCLUSIONS

We introduced an objective, quantifiable, and observer-independent parameter, the MPP score, representing the aggressiveness of tumor growth and infiltration in TSCC. We showed its prognostic relevance especially in pT1-pT2 category TSCC, and its possible use in ML models predicting TCSS and occult lymph node metastases.

An Oral Microbial Biomarker for Early Detection of Recurrence of Oral Squamous Cell Carcinoma

Changes in the oral microbiome are associated with oral squamous cell carcinoma (OSCC). Oral microbe-derived signatures have been utilized as markers of OSCC. However, the structure of the oral microbiome during OSCC recurrence and biomarkers for the prediction of OSCC recurrence remains unknown. To identify OSCC recurrence-associated microbial biomarkers for the prediction of OSCC recurrence, we performed 16S rRNA amplicon sequencing on 54 oral swab samples from OSCC patients. Differences in bacterial compositions were observed in patients with vs without recurrence. We found that Granulicatella, Peptostreptococcus, Campylobacter, Porphyromonas, Oribacterium, Actinomyces, Corynebacterium, Capnocytophaga, and Dialister were enriched in OSCC recurrence. Functional analysis of the oral microbiome showed altered functions associated with OSCC recurrence compared with nonrecurrence. A random forest prediction model was constructed with five microbial signatures including Leptotrichia trevisanii, Capnocytophaga sputigena, Capnocytophaga, Cardiobacterium, and Olsenella to discriminate OSCC recurrence from original OSCC (accuracy = 0.963). Moreover, we validated the prediction model in another independent cohort (46 OSCC patients), achieving an accuracy of 0.761. We compared the accuracy of the prediction of OSCC recurrence between the five microbial signatures and two clinicopathological parameters, including resection margin and lymph node counts. The results predicted by the model with five microbial signatures showed a higher accuracy than those based on the clinical outcomes from the two clinicopathological parameters. This study demonstrated the validity of using recurrence-related microbial biomarkers, a noninvasive and effective method for the prediction of OSCC recurrence. Our findings may contribute to the prognosis and treatment of OSCC recurrence.

Surgical Extent for Oral Cancer: Emphasis on a Cut-Off Value for the Resection Margin Status: A Narrative Literature Review

The optimal cut-off point of the resection margin was recently debated in oral cancer. To evaluate the current evidence of the dynamic criteria of the resection margin, a review of the available literature was performed. Studies were sourced from PubMed and EMBASE by searching for the keywords "mouth neoplasm", "oral cancer", "oral cavity cancer", "oral squamous cell carcinoma", "tongue cancer", "margins of excision", "surgical margin" and "resection margin". We found approximately 998 articles on PubMed and 2227 articles on EMBASE. A total of 3225 articles was identified, and 2763 of those were left after removing the duplicates. By applying advanced filters about the relevance of the subjects, these were narrowed down to 111 articles. After the final exclusion, 42 full-text articles were reviewed. The universal cut-off criteria of 5 mm used for determining the resection margin status has been debated due to recent studies evaluating the impact of different margin criteria on patient prognosis. Of note, the degree of the microscopic extension from the gross tumor border correlates with tumor dimensions. Therefore, a relatively narrow safety margin can be justified in early-stage oral cancer without the additional risk of recurrence, while a wide safety margin might be required for advanced-stage oral cancer. This review suggests a surgical strategy to adjust the criteria for risk grouping and adjuvant treatments, according to individual tumor dimensions or characteristics. In the future, it might be possible to establish individual tumor-specific surgical margins and risk stratification during or after surgery. However, the results should be interpreted with caution because there is no strong evidence (e.g., prospective randomized controlled studies) yet to support the conclusions. Our study is meaningful in suggesting future research directions and discussions.

Surgical margins of the oral cavity: is 5 mm really necessary?

Background

Squamous cell carcinoma is the most common malignancy of the oral cavity. Primary treatment involves surgical resection of the tumour with a surrounding margin. Historically, the most commonly accepted margin clearance is 5 mm. This distance is controversial, with recent publications suggesting closer margins do not impact local recurrence and survival. The objective of this study is to determine the closest surgical margin that does not impact local recurrence and overall survival.

Methods

A retrospective review of the London Health Sciences Centre Head and Neck Multidisciplinary Clinic between 2010 and 2018 was performed. Demographic data, subsite, tumour staging, treatment modality, margins, and survival outcomes were analyzed. The primary endpoint was local recurrence free survival. Secondary endpoints included recurrence-free survival and overall survival. Descriptive statistics, as well as univariable and multivariable Cox proportional hazards regression modelling were performed for all patients.

Results

Four-hundred and twelve patients were included in the study, with a median follow-up of 3.3 years. On univariable analysis, positive margins and margins < 1 mm were associated with significantly worse local recurrence-free survival, recurrence-free survival, and overall survival (p < 0.05), compared to margins > 5 mm. Patients with surgical margins > 1 mm experienced similar outcomes to those with margins > 5 mm. Multivariable analysis identified age of diagnosis, alcohol consumption, pathological tumour and nodal category as predictors of local recurrence free survival.

Conclusions

Although historical margins for head and neck surgery are 5 mm, similar outcomes were observed for margins greater than 1 mm in our cohort. These findings require validation through multi-institutional collaborative efforts.

Graphical abstract

Surgical Margins Status and Prognosis after Resection of Oral Cavity Squamous Cell Carcinoma: Results from a Taiwanese Nationwide Registry-Based Study

Simple Summary

While the prognostic role of surgical margins in oral cavity squamous cell carcinoma is well-established, the optimal cutoff values for margin status remain controversial. This study addressed this issue in a large sample of 13,768 patients included in a nationwide registry in Taiwan. The identification of the most suitable cutoff value for surgical margins was conducted using 5-year local control as the outcome of interest. On analyzing the margin status—categorized as 0, 0.1–4 and > 4 mm—the 5-year outcomes were as follows: local control, 87, 89 and 92%; disease-specific survival, 57, 76 and 81%; overall survival, 47, 67 and 74%, respectively. Collectively, these data indicate that a margin status >4 mm can be considered as adequate.

Abstract

(1) Background: The optimal cutoff value that maximizes the prognostic value of surgical margins in patients with resected oral cavity squamous cell carcinoma has not yet been identified. (2) Methods: Data for this study were retrieved from the Taiwan Cancer Registry Database. A total of 13,768 Taiwanese patients with oral cavity squamous cell carcinoma were identified and stratified according to different margin statuses (0, 0.1–4 and > 4 mm). The five-year local control, disease-specific survival and overall survival rates were the main outcome measures. (3) Results: The 5-year local control, disease-specific survival and overall survival rates of patients with close margins (0 and 0.1–4 mm) were significantly lower than those observed in patients with clear margins (> 4 mm; all p values < 0.001). In multivariate analysis, margin status, depth of invasion and extra-nodal extension were identified as independent adverse prognostic factors for 5-year local control. (4) Conclusions: A thorough assessment of surgical margins can provide a reliable prognostic prediction in patients with OCSCC. This has potential implications for treatment approaches tailored to the individual level. The achievement of clear margins (>4 mm) should be considered a key surgical goal to improve outcomes in this patient group.

The impact of lymph node density as a predictive factor for survival and recurrence of tongue squamous cell carcinoma

The oral tongue is considered the most frequently involved site in cases of oral squamous cell carcinoma (OSCC). Lymph node (LN) density, defined as the number of positive LNs divided by the total number of resected LNs, is considered an important prognostic factor in OSCC; however the cut-off point remains uncertain. A retrospective study was performed involving 104 patients who underwent a glossectomy procedure for oral tongue squamous cell carcinoma (OTSCC) between the years 2008 and 2018. LN density and other related prognostic factors, including pathological N-stage (pN), extranodal extension (ENE), perineural invasion (PNI), and depth of invasion (DOI), were investigated in relation to survival and recurrence rates. pN + stage, the presence of ENE, the presence of PNI, and increased DOI were found to be associated with increased LN density values, as well as lower patient survival and higher recurrence rates. The statistical analysis identified a cut-off point for LN density of 2.5%. In advanced stage disease, LN density values above 2.5% had a significant impact on the survival rate (P = 0.005), as well as the recurrence rate (P = 0.038). In conclusion, in addition to other previously known prognostic factors, LN density may serve as a strong prognostic factor for survival and recurrence in patients with advanced- and early-stage OTSCC.

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.

Tumor dimension-dependent microscopic extensions of hypopharyngeal cancer: Therapeutic implications for larynx-preserving hypopharyngectomy

INTRODUCTION

Hypopharyngeal cancer (HPC) is well characterized by the early submucosal spread of cancer cells into adjacent subsites of the hypopharynx and deep tissues, advocating a wide extent of treatment. However, the microscopic extensions (ME) from gross tumors, according to the primary tumor dimensions, has not been reported in detail.

METHODS

We included patients who underwent upfront curative surgery, and retrospectively reviewed pathology specimens from 45 HPC cases. The distance of the MEs, defined as tumor infiltration beyond the gross tumor border on the submucosal and deep sides, was measured. We analyzed potential correlations between MEs and various physical tumor factors.

RESULTS

A rough linear correlation between the submucosal ME and the maximal diameter of tumors was found (p < .001, r²  = 0.225). Deep MEs did not correlate with tumor physical factors. However, the MEs differed significantly by the T status (p = .033 and .015 in submucosal and deep sides). In T1-2 tumors, the submucosal MEs were less than 0.5 cm, whereas those of T3-4 tumors were 1.5-2.0 cm.

CONCLUSION

In HPC, local MEs beyond the gross tumor border correlated with primary tumor T status. Our findings support that the surgical safety margin for HPC can be adjusted according to tumor dimension.

Success Rate of Benign Oral Squamous Papilloma Treatments After Different Surgical Protocols (Conventional, Nd:YAG, CO2 and Diode 980 nm Lasers): A 34-Year Retrospective Study

Objective: The aim of our retrospective study is to compare the long-term recurrence rate of the benign oral squamous papilloma (OSP) with different laser-assisted treatments and conventional procedures (use of scalpels) aiming to suggest the most suitable surgical protocol showing the lowest recurrence rate. Background: A retrospective multicenter DATA collection between 1985 and 2019 covering 781 OSP cases concerning different surgical protocols used for the treatment of OSP was done and included the use of different laser wavelengths [neodymium-doped yttrium-aluminum-garnet (Nd:YAG), carbon dioxide (CO₂), and Diode 980 nm] and the conventional surgeries using the scalpel. The age, sex, and the oral location of the OSP were noted. Methods: Three different surgical protocols were selected in our study: protocol 1 regrouped surgical procedures performing the excision of OSP with an in-depth safety margin of 1 mm and just at the base of the tumor with reduced excision of the grossly normal marginal mucosa around the tumor (0-1 mm). Protocol 2 and 3 were similar to protocol 1, but with an additional excision of 1-2 mm and ≥3 mm of the grossly normal marginal mucosa, respectively, for group 2 and 3. All laser-treated OSP wounds were left without sutures. In the conventionally treated OSP, sutures were regularly performed. Follow-up was done after 15 days and at 1, 6, and 18 months. The three included wavelengths were Nd:YAG (1064 nm), CO₂ laser (10,600 nm), and diode laser (980 nm). Results: After 18 months of follow-up, the highest success rate was obtained with protocol 3 (100% with Nd:YAG, 99% with CO₂, 98.4% with diode, and 99% with the scalpel), which was significantly higher than the values of protocol 2 (96.6% with Nd:YAG, 91% with CO₂, 96% with diode, and 95% with the scalpel) and the protocol 1 (38% with Nd:YAG, 29% with CO₂, 33% with diode, and 30% with the scalpel). The oral locations of OSP were 30% on palates, 30% on the tongue, 16% on cheek, 14% on lips, and 10% on other locations. Conclusions: The lowest recurrence rate was observed when a minimum of three millimeters (≥3 mm) of grossly normal aspect mucosa around the OSP was included in the excisions. The laser wavelengths and the use of scalpel did not show any significant difference in terms of recurrence.

Specimen-driven intraoperative assessment of resection margins should be standard of care for oral cancer patients

With an incidence of 350.000 new cases per year, cancer of the oral cavity ranks among the 10 most common solid organ cancers. Most of these cancers are squamous cell carcinomas. Five-year survival is about 50%. It has been shown that clear resection margins (>5 mm healthy tissue surrounding the resected tumor) have a significant positive effect on locoregional control and survival. It is not uncommon that the resection margins of oral tumors are inadequate. However, when providing the surgeon with intraoperative feedback on the resection margin status, it is expected that obtaining adequate resection margins is improved. In this respect, it has been shown that specimen-driven intraoperative assessment of resection margins is superior to defect-driven intraoperative assessment of resection margins. In this concise report, it is described how a specimen-driven approach can increase the rate of adequate resections of oral cavity squamous cell carcinoma as well as that it is discussed how intraoperative assessment can be further improved with regard to the surgical treatment of oral cavity squamous cell carcinoma.

Intraoperative Assessment of the Resection Specimen Facilitates Achievement of Adequate Margins in Oral Carcinoma

Background

Inadequate resection margins in oral cavity squamous cell carcinoma have an adverse effect on patient outcome. Intraoperative assessment provides immediate feedback enabling the surgeon to achieve adequate resection margins. The goal of this study was to evaluate the value of specimen-driven intraoperative assessment by comparing the margin status in the period before and the period after the introduction of specimen-driven assessment as a standard of care (period 2010-2012 vs period 2013-2017).

Methods

A cohort of patients surgically treated for oral squamous cell carcinoma at the Erasmus MC Cancer Institute, Rotterdam, between 2010-2012 was studied retrospectively and compared to results of a prospectively collected cohort between 2013-2017. The frequency, type and results of intraoperative assessment of resection margins were analyzed.

Results

One hundred seventy-four patients were included from 2010-2012, 241 patients were included from 2013-2017. An increase in the frequency of specimen-driven assessment was seen between the two periods, from 5% in 2010-2012 to 34% in 2013-2017. When performing specimen-driven assessment, 16% tumor-positive resection margins were found in 2013-2017, compared to 43% tumor-positive resection margins overall in 2010-2012. We found a significant reduction of inadequate resection margins for specimen-driven intraoperative assessment (p < 0.001). Also, tumor recurrence significantly decreased, and disease-specific survival improved when performing specimen-driven intraoperative assessment.

Conclusions

Specimen-driven intraoperative assessment improves resection margins and consequently, the outcome of oral cancer patients. We advocate this method as standard of care.

The presence of risk factors and corresponding treatment strategies post-surgical resection in stage IV hypopharyngeal squamous cell carcinoma patients: a retrospective cohort study

Background

This study aims to explore the adverse features and determine whether adjuvant chemoradiation after surgical resection can benefit stage IV hypopharyngeal squamous cell carcinoma (HSCC) patients.

Methods

We conducted a retrospective review covering 267 patients with stage IV HSCC. Propensity score-matched analysis was employed to reduce selection bias.

Results

T3–T4 or N2c–N3 stage, positive surgical margin, extracapsular spread and lymphovascular invasion were adverse features for overall survival (OS) in stage IV HSCC patients. For patients possessing these adverse features, those who received postoperative adjuvant treatment (PAT) had significantly better OS and recurrence-free survival (RFS) than patients who did not (P value =0.000 and 0.007, respectively). In addition, adjuvant chemoradiation demonstrated better OS and RFS compared to adjuvant radiation (P value =0.030 and 0.017, respectively). However, PAT showed no significant impact on OS and RFS (P value =0.776 and 0.847, respectively) in patients without adverse features.

Conclusions

Adjuvant treatments are recommended for stage IV HSCC patients that possess adverse features of pT3 and pT4 stages, N2c and N3 stages, positive surgical margin, extracapsular spread and lymphovascular invasion. For these patients, postoperative adjuvant chemoradiotherapy (CRT) is preferred. For patients without adverse features, observation and regular re-examination is sufficient post tumour resection.

The impact of surgical margin status on the outcomes of locally advanced hypopharyngeal squamous cell carcinoma treated by primary surgery

BACKGROUND

The extent of surgical safety margin remained unclear in hypopharyngeal carcinoma surgery.

AIM

The purpose of this study was to evaluate the influence of surgical margin status on the outcomes of patients with advanced hypopharyngeal carcinoma.

MATERIAL AND METHODS

A retrospective analysis of clinical data was performed in 205 patients with stage III/IV hypopharyngeal carcinoma treated by primary surgery between January 2005 and December 2014. There were 129 patients with clear surgical margins (≥5 mm) and 76 with close surgical margins (<5 mm). The clinical characteristics and treatment outcomes were compared between the two groups.

RESULTS

Close surgical margin (cSM) was found to be a significant risk factor for local recurrence, overall survival (OS) and disease-specific survival (DSS). Analysis by stratification according to pT classification showed that the OS and DSS rates of T1/T2 tumors with clear surgical margins (nSM) were significantly higher than those with cSM (p < .05), while there was no significant difference in the OS and DSS rates between T3/T4 tumors with cSM and nSM (p > .05).

CONCLUSIONS AND SIGNIFICANCE

The tailored extent of surgical resection margin was recommended for locally advanced hypopharyngeal carcinomas according to primary tumor stage.