Depth of invasion in early stage oral cavity squamous cell carcinoma: The optimal cut-off value for elective neck dissection

Comparison of pre-operative ultrasonic depth of invasion (DOI) with histopathological depth of invasion (DOI) in gingivobuccal sulcus squamous cell carcinoma with neck nodal metastasis

INTRODUCTION

Head and neck carcinomas have the highest incidence among other carcinomas in the several regions of the country with trends still rising in the third population. The tumor mass is not planar but rather grows three-dimensionally, so surgeons should have the knowledge of the third dimension, which is the depth of invasion (DOI). Nowadays advanced techniques have been introduced to measure the preoperative depth of invasion of the primary tumor, i.e., ultrasonography (USG) scans. Ultrasonography (USG) scan is still considered a preoperative gold standard to measure DOI because of its advantages of radiation-free imaging and excellent tumor visualization, economical, non-invasive, and real-time images that can be obtained spontaneously. The primary objective of the study was to evaluate and compare pre-operative ultrasonic depth of invasion (DOI) with histopathological DOI in gingivobuccal sulcus squamous cell carcinoma with neck nodal metastasis.

MATERIALS AND METHODOLOGY

This is a single-center prospective study including 51 patients reporting to our unit from November 2019 to November 2021 who were subjected to surgery. Preoperative USG evaluation of lesion was performed on all patients which recorded DOI.Similarly, postoperatively, all the resected specimens were examined for the histopathological DOI.The value obtained preoperatively from USG examinations was then compared with histopathological DOI postoperatively. Correlation coefficient analysis was studied using a scatter diagram by Karl Pearson and a dependent t-pair test. A chi-square with Yates's correction test was used to study the statistical association between USG DOI and lymph node metastasis (LNM).

RESULTS

A total of 51 patients were included in the study of which 40(78.4%) were male patients and 11(21.6%) were female patients. DOI measured preoperatively from the USG scan in these cases ranged from 6 mm to 37 mm with an average of 19.41 mm. Histopathological DOI measured in all these patients ranged from 1.3 mm to 16 mm with an average of 7.26 mm. A statistical significance was noted between preoperatively measured DOI from the USG scan and postoperatively (histologically) measured DOI with a p-value of 0.0316. Cervical lymph node metastasis was USG positive in 15 (29.41%) patients out of 51 patients. Chi-square test with Yates's correction = 0.2721, P = 0.6020, noted association between the USG DOI and the occurrence of the cervical lymph node metastasis.

CONCLUSION

DOI is clearly a potentially useful and objectively measurable prognostic tool. USG imaging studies are used preoperatively to locate the extension of the lesion proper and to measure the area of the deepest invasion of the tumour. Preoperatively, DOI data obtained helps the surgeon to plan 3-dimensional clearance of the disease. Although USG scans lack in early detection of bone invasion in gingivo buccal sulcus carcinoma, could be a adjuvant rapid axillary scan in determining the third dimension of tumor that is DOI and cervical lymph node metastasis.

Nomogram vs. Depth of invasion for predicting occult lymph node metastasis in cT1-2N0 buccal squamous cell carcinoma

OBJECTIVE

To develop a nomogram prediction model for occult lymph node metastasis (LNM) in patients with cT1-2N0 buccal squamous cell carcinoma (BSCC), then to compare its predictive efficacy against depth of invasion (DOI).

METHODS

Clinical data were retrieved for patients undergoing primary tumor resection and neck dissection from June 2020 to August 2024. Based on the risk factors screened by Lasso regression, we established four candidate models: logistic regression, random forest, support vector machine, and XGboost. The optimal model was determined by comparing the values of areas under the receiver-operating characteristic curve (AUC), then the nomogram was ultimately plotted accordingly to visualize the results.

RESULTS

Two hundred and fifty patients were enrolled. The screened variables include Ki-67, tumor differentiation grade, surgical margin status, perineural invasion, DOI, and smoking. With similar good performance from both the training and test cohorts (AUC, 0.726 vs. 0.782) and good calibration, the logistic regression model performed the best overall, and was thus selected for creating a nomogram. The nomogram was superior to DOI cut-off values of 3 mm and 4 mm in predicting occult LNM, with a higher AUC (0.741 vs. 0.543 and 0.595) and more net benefits. Compared with DOI < 4 mm, at a 9.51 % risk of LNM, the nomogram identified an equivalent number of cases (n = 64) for not undergoing elective neck dissection (END), while successfully reducing 2 false-negative cases (2 vs. 4) with insufficient treatment.

CONCLUSIONS

The nomogram described here prevails over DOI in predicting occult LNM in early-stage BSCC, and provide effective guidance for END.

Head and Neck Cancer in Fanconi Anemia: Report of 11 Cases and a Systematic Review

BACKGROUND/OBJECTIVES

Head and neck cancer is one of the most common malignancies in patients with Fanconi anemia (FA), with a greater than 500-fold incidence of head and neck squamous cell carcinoma. Treatment of HNSCC in these patients is particularly challenging because of poor tolerance to radiation therapy and to some chemotherapeutic agents such as cisplatin. For these reasons, new research is needed to determine the best treatment course for these patients. With this goal in mind, we assessed the characteristics of head and neck squamous cell carcinoma (SCC) in Fanconi anemia (FA).

SUBJECTS AND METHODS

Data for 11 patients (mean age 31 years) with head and neck SCC and FA attended to between 2005 and 2021 were analyzed.

RESULTS

The primary tumor site was the oral cavity in eight patients, and five had advanced stages. All patients underwent primary tumor resection. Four patients received adjuvant radiotherapy (mean 57.2 Gy), but three developed toxicity. The mean follow-up was 48.4 months. Six patients experienced 19 episodes of primary tumor recurrence and five developed secondary head and neck tumors. The 3-year disease-free survival was 47%, and the 5-year cause-specific survival was 48%. These findings are similar to the data for 72 patients collected from the literature.

CONCLUSIONS

The prognosis of head and neck cancer in patients with Fanconi anemia is poor, with an overall survival lower than 50% at 5 years.

Depth of Invasion Threshold for Recommending Elective Neck Dissection in T1 or T2 Oral Squamous Cell Carcinoma

BACKGROUND

There is variability in the literature on the role of the depth of invasion (DOI) for recommending an elective neck dissection (END).

PURPOSE

The purpose of the study is to estimate the DOI threshold for recommending an END.

STUDY DESIGN, SETTING, SAMPLE

A retrospective cohort study was performed at McGill University Health Centre from 2008 to 2018 with 5 years of follow-up. The sample was subjects with clinical T1/T2 oral squamous cell carcinoma and clinically negative neck. Subjects with previous head and neck cancer were excluded.

PREDICTOR VARIABLE

The primary predictor variable was DOI measured from the basement membrane of the adjacent normal mucosa on final pathology, coded as <4 mm or ≥4 mm. DOI is a continuous variable converted to a binary variable.

MAIN OUTCOME VARIABLE

The main outcome variable was time to development of neck disease (RD+) defined as the time from surgery to development of pathologic nodes. Time to RD+ for pathologic nodes discovered from the END was considered 0 months. The secondary outcome variable was overall survival.

COVARIATES

Demographics (age, sex, and smoking/alcohol history) and tumor characteristics (tumor location, clinical T, tumor differentiation, perineural invasion, and lymphovascular invasion) were analyzed.

ANALYSES

Time to RD+ and survival were analyzed using Cox hazard ratio, Kaplan-Meier curves, and log-rank test. Student's t-test and χ2 test were used for bivariate analyses; P ≤ .05 was statistically significant.

RESULTS

The final sample were 64 subjects (average age 65.25 [standard deviation 13.06] years and 36 [56.2%] males). Twenty-nine subjects had DOI < 4 mm, and the 5-year RD+ was 3.4% (the 1 occurrence of RD+ was at 5.3 months). Thirty-five subjects had DOI ≥ 4 mm, and the 5-year RD+ was 45.7% (15 subjects had RD+ discovered from the END, and 1 subject had RD+ at 7.6 months). DOI ≥ 4 mm had significantly higher risk of RD+ than DOI < 4 mm (hazard ratio 17.91; 95% confidence interval 2.37 to 135.3; P = .01), which remained significant after adjusting for clinical T, tumor differentiation, perineural invasion, and lymphovascular invasion (hazard ratio 9.53; 95% confidence interval 1.12 to 81.44; P < .05). The shallowest DOI with >20% risk of RD+ was in the DOI 4 mm to 4.9 mm group.

CONCLUSION AND RELEVANCE

Among patients with oral squamous cell carcinoma of T1 or T2 and clinically negative necks, END should be considered with DOI ≥ 4 mm.

Historical milestones in the evolution of the procedure of neck dissection

Objective

Although neck dissection has evolved to become an integral part of the surgical armamentarium for managing head and neck cancers, the manner in which the procedure has reached its present state is worth revisiting.

Data Sources

Published original articles, reviews, clinical practice guidelines, and consensus statements related to the basis, indication, and classification of the neck dissection.

Methods

This review discusses some of the critical milestones before and after the description of the procedure of neck dissection by George Crile Sr. in 1905, which eventually played a role in the evolution of this commonly performed oncosurgical procedure.

Results

Several large observational studies of the twentieth century and multicentric randomized trials at the turn of the twenty-first century have shaped neck dissection into a safe and reliable oncosurgical procedure.

Conclusions

From being a radical surgery that was done mostly in large nodal diseases for curative or palliative purposes to becoming a simple procedure that is carried out even in node-negative cases of head and neck cancers for prognostic purposes, the procedure of neck dissection has come a long way and continues to evolve.

Pathological Risk Factors for Occult Nodal Metastasis in Early-Stage Squamous Cell Carcinoma of the Oral Cavity

Occult neck metastasis is the presence of metastasis in the cervical lymph nodes that cannot be radiologically or clinically identified. Presence of metastasis in any neck node can have a significant impact on overall survival of patients with oral squamous cell carcinoma (OSCC). Our aim was to analyze the correlation of various histopathological parameters with occult nodal metastasis in early-stage OSCC and to obtain an optimal DOI cut-off value for predicting its increased risk. We conducted a retrospective study on patients who reported to our institute with clinical stage I and II OSCC. The patients having well-differentiated and moderately differentiated OSCC were included. Association of various histopathological parameters with occult nodal metastasis was assessed using statistical analysis. A total of 102 patients of early-stage well-differentiated and moderately differentiated OSCC with clinically negative necks who underwent elective neck dissection at our institute from the year 2018 to 2023 were enrolled in the study. Depth of invasion (DOI), perineural invasion (PNI), worst pattern of invasion (WPOI), and grade of tumor differentiation were the histopathological parameters entered into the univariate regression analysis as predictive variables, and they were found to be predictors of occult nodal metastasis. An optimal DOI cut-off value of 5.5 mm was obtained for predicting the increase in the risk of occult nodal metastasis. DOI, PNI, WPOI, and grade of tumor differentiation are predictors of occult nodal metastasis. There is a need for searching methods for preoperative and intraoperative detection of all these histopathological factors so that unnecessary elective neck treatment can be avoided.

Prognostic significance of anatomic site-specific depth of invasion in oral squamous cell carcinoma - An eastern Indian multi-center study

A crucial parameter in determining the prognosis of oral cavity cancer is depth of invasion (DOI). This research aimed to correlate pathological DOI at different intra-oral anatomical sites for oral squamous cell carcinoma (OSCC) with the risk of regional lymph node metastasis (LNM). This study also investigated the correlation of 3-year overall survival (OS) and disease-specific survival (DSS) with tumor depth. DOI measurement of the primary tumor at different intra-oral anatomic sites of clinically node negative patients who underwent curative surgery with elective neck dissection (END) was carried out as per AJCC 8th Edition staging guidelines in 3 DOI groups of ≤5 mm(A), >5 to ≤10 mm(B) and >10 mm(C). Association of groupwise DOI values with histopathological parameters including LNM and 3 years survival was evaluated. Univariate and multivariate logistic regression analysis (Odds ratio (OR) = 1.1 95 % CI: 1.0-1.2, p < 0.05) showed DOI to be a significant predictor for sub-clinical nodal metastasis observed in 136/382 OSCC patients. Receiver operating curve suggested that at 5 mm DOI (4 mm for early-stage OSCC), the risk of occult LNM was >20 % for all intra-oral sites combined. DOI <5 mm group demonstrated a superior 3-year OS (OR = 19.8 % CI: 7.8-49.9) and DSS (OR = 14.7 % CI: 5.9-37.0). Thus, DOI is an independent predictor of nodal metastasis and has significant association with LNM, OS and DSS. Our findings suggest that a DOI of ≥4 mm is an accurate cut-off value for performing END in early-stage OSCC and > 5 mm for advanced cases across all evaluated oral anatomic sites.

Evaluation of Depth of Invasion on Contrast-Enhanced Computed Tomography in Tumours of the Gingivobuccal Complex-A Retrospective Analysis

Depth of invasion (DOI) is an established independent prognostic factor in oral squamous cell carcinoma (OSCC) and also predicts cervical nodal metastasis. Preoperative determination of DOI based on imaging can aid in decision-making regarding neck dissection or determining the prognosis of the disease. This study aimed to correlate the DOI measured on contrast enhanced computed tomography (rDOI) with the pathologically measured DOI (pDOI). Retrospective data of patients with OSCC of the gingivobuccal complex from January 2023 to July 2023 was collected. Two radiologists independently measured the DOI on axial and coronal planes of CECT. The correlation between rDOI and pDOI was determined. Stepwise multiple linear regression analysis was performed to predict the pDOI using rDOI. ROC curve analysis was performed for the rDOI as measured on both axial and coronal sections in predicting the nodal metastasis. A total of 59 patients were included in the study. The mean rDOI was 11.06 mm on axial section and 10.9 mm on coronal section, and pDOI was 9.7 mm. Spearman's correlation coefficient between pDOI and rDOI measured on axial (rho = 0.61; p value = 0.001) and coronal (rho = 0.62; p value = 0.001) sections implied strong correlation which was statistically significant. The present study attempted to establish the correlation and accuracy of CECT-determined rDOI in axial and coronal planes in gingivobuccal complex tumours. Multicentric studies with a larger sample size are mandated to augment the results obtained in this study.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13193-024-01998-8.

Tumor thickness is associated with metastasis in patients with submucosal invasive adenocarcinoma of the esophagogastric junction

In submucosal invasive adenocarcinoma of the esophagogastric junction (pT1b-SM AEG), the extent of tumor submucosal (SM) invasion is measured using the vertical depth of SM invasion with the muscularis mucosa. This study aimed to investigate whether tumor thickness and depth of invasion without accounting for muscularis mucosa were superior to the vertical depth of SM invasion as metastasis predictors. We enrolled patients with pT1b-SM AEG who underwent endoscopic resection or surgical resection (SR) at our institution between January 2011 and September 2019 and were followed up for ≥2 years. The relationship between metastasis and clinicopathological factors was examined. Metastasis was defined as pathologically confirmed lymph node metastasis in the surgical specimen or recurrence during follow-up. This study included 57 patients (44 men; median age, 72 years). Endoscopic resection and SR were performed in 16 and 41 patients, respectively. Nine patients were diagnosed with metastasis: five who underwent SR showed pathologically confirmed lymph node metastasis in the surgical specimens, and four experienced recurrences during a median follow-up of 48 months. Univariate analyses showed that tumor thickness was significantly associated with metastasis (P = 0.021), and the vertical depth of SM invasion (P = 0.48) and depth of invasion (P = 0.38) were not. Furthermore, in multivariate analysis, tumor thickness ≥2800 μm (odds ratio, 38.70; P = 0.013) was a significant predictor for metastasis. Tumor thickness may be a more convenient and useful predictor of metastasis in patients with pT1b-SM AEG than the vertical depth of SM invasion.

Depth of Invasion in Early Oral Cancer: Is 4MM a Threshold for Elective Neck Dissection?

Lymph node metastasis is one of the most important prognostic factors in oral squamous cell carcinoma. In early stage oral cancers, Depth of invasion (DOI) is a predictor for lymph node metastasis. The aim of this study was to evaluate if DOI 4 mm can be considered as a threshold for clinical decision making on elective neck dissection (END) in early oral cancer, by assessing the association of DOI and the risk of occult lymph node metastasis in early Oral squamous cell carcinoma (OSCC). A retrospective study was conducted on 319 patients with early pT1-2 OSCC who were clinically N negative. All patients underwent primary resection and END. The patients were divided into two groups based on DOI: < 4 mm and ≥ 4 mm. Nodal metastases were then noted for each group. The rate of nodal metastasis in respect to tumor size was also observed. Out of 111 patients having DOI < 4 mm only 15 (4.7%) had lymph node metastasis, whereas out of 208 patients having DOI ≥ 4 mm, 81 patients (25.4%) had neck node metastasis, with p value < 0.05. Tumors having DOI ≥ 4 mm has higher chances of occult metastasis and also increased probability of other prognostic factors like PNI and LVI, suggesting that DOI ≥ 4 mm can be considered a cut - off value for performing END.

Parameters to assess the necessity of adjuvant therapy for early-stage oral squamous cell carcinoma

OBJECTIVE

One-third of head and neck squamous cell carcinomas are early-stage oral cavity squamous cell carcinomas (OCSCC). Despite a high curative rate, 20% of early-stage OCSCC patients do not achieve long-term survival. This study evaluates the role of adjuvant therapy (ADJ) in delaying disease progression and prolonging survival.

METHODS

This single-institute retrospective cohort study enrolled 481 early-stage OCSCC patients, 16% (78/481) of whom received ADJ. It was reported according to the STROBE guidelines. Cox proportional hazards regression and Kaplan-Meier survival curves were employed to identify suitable candidates for ADJ.

RESULTS

The 5-year locoregional recurrence-free survival (LR-RFS) and overall survival rates were 73.2% and 84.9%, respectively. Positive margins and advanced depth of invasion (DOI) were independent predictors of LR-RFS. For patients with positive margins, adjuvant chemoradiotherapy (CRT) was superior to adjuvant radiotherapy alone in improving LR-RFS (hazard ratios for adjuvant CRT vs. none, 0.042; adjuvant radiotherapy alone vs. none, 0.702). Excluding positive margins, advanced DOI was the most critical factor in assessing the need for ADJ. Positive margins and advanced DOI were more appropriate criteria than EORTC 22931/RTOG 9501 for evaluating adjuvant CRT.

CONCLUSIONS

Adjuvant CRT was indicated for patients with positive margins and advanced DOI to improve survival outcomes.

Intraoral ultrasonography: an adjunct in oral onco-surgery

OBJECTIVE

To determine the precision and accuracy of intraoral sonography in assessing the depth of invasion in oral cancer.

MATERIAL AND METHODS

A prospective study was conducted in 30 cases of oral cancer. Subjects were subjected to computerised tomography and intraoral sonography before surgery. The depth of invasion assessed through clinical palpation and radiological tools was compared with surgical histopathology.

RESULTS

The depth of invasion assessed on clinical palpation and computerized tomography had statistically significant difference with histopathology whereas intraoral sonography didn't show any difference. The intraoral sonography and computerised tomography had comparable precision and accuracy, with a slight dominance of the computerised tomography in assessing the tumor's depth of invasion greater than 4 mm. However, intraoral sonography was more precise and accurate than computerised tomography in assessing the depth of invasion beyond 10 mm.

CONCLUSION

Intraoral sonography was found to be a reliable tool in the assessment of the depth of invasion in oral cancer. It can prove beneficial during surgery in achieving tumour-free surgical margins.

MRI-based deep learning and radiomics for prediction of occult cervical lymph node metastasis and prognosis in early-stage oral and oropharyngeal squamous cell carcinoma: a diagnostic study

INTRODUCTION

The incidence of occult cervical lymph node metastases (OCLNM) is reported to be 20-30% in early-stage oral cancer and oropharyngeal cancer. There is a lack of an accurate diagnostic method to predict occult lymph node metastasis and to help surgeons make precise treatment decisions.

AIM

To construct and evaluate a preoperative diagnostic method to predict OCLNM in early-stage oral and oropharyngeal squamous cell carcinoma (OC and OP SCC) based on deep learning features (DLFs) and radiomics features.

METHODS

A total of 319 patients diagnosed with early-stage OC or OP SCC were retrospectively enrolled and divided into training, test and external validation sets. Traditional radiomics features and DLFs were extracted from their MRI images. The least absolute shrinkage and selection operator (LASSO) analysis was employed to identify the most valuable features. Prediction models for OCLNM were developed using radiomics features and DLFs. The effectiveness of the models and their clinical applicability were evaluated using the area under the curve (AUC), decision curve analysis (DCA), and survival analysis.

RESULTS

Seventeen prediction models were constructed. The Resnet50 deep learning (DL) model based on the combination of radiomics and DL features achieves the optimal performance, with AUC values of 0.928 (95% CI: 0.881-0.975), 0.878 (95% CI: 0.766-0.990), 0.796 (95% CI: 0.666-0.927), and 0.834 (95% CI: 0.721-0.947) in the training, test, external validation set1, and external validation set2, respectively. Moreover, the Resnet50 model has great prediction value of prognosis in patients with early-stage OC and OP SCC.

CONCLUSION

The proposed MRI-based Resnet50 DL model demonstrated high capability in diagnosis of OCLNM and prognosis prediction in the early-stage OC and OP SCC. The Resnet50 model could help refine the clinical diagnosis and treatment of the early-stage OC and OP SCC.

Role of Computed Tomography in Prediction of Depth of Invasion and Cervical Lymph Node Metastasis in Oral Cancer

Objectives

The primary aim is to determine the accuracy of contrast-enhanced computed tomography (CT) in evaluation of depth of invasion (DOI) and detection of cervical node metastasis. We also analysed the relation between radiographic DOI (rDOI) and cervical lymph node metastasis.

Materials and Methods

We have retrospectively reviewed 201 oral squamous cell carcinoma (SCC) patients. The rDOI was compared with histological DOI. Sensitivity, specificity, accuracy, and negative (NPV) and positive (PPV) predictive values were evaluated for CT scan in predicting nodal metastasis. The relation between rDOI and lymph node metastasis was analysed using ROC curve.

Results

rDOI correlated significantly with histologic DOI for oral tongue, buccal mucosa, gingiva, and mucosal lip SCC (P < 0.05) and for tumours with rDOI > 5 mm. The sensitivity, specificity, PPV, NPV and accuracy rate of CT scan were found to be 84.71%, 50.86%, 55.81%, 81.94% and 65.17%, respectively. Tumours with rDOI > 16 mm had significant (P < 0.001) chance of having neck node metastasis.

Conclusion

CT-derived DOI correlates significantly with pathological DOI although both are not similar. CT scan can predict nodal metastasis in fairly accurate manner using the four radiographic criteria used in this study. Radiographic depth of invasion can be used as predictor of cervical node metastasis.

Impact of histopathological parameters in prognosis of oral squamous cell carcinoma

OBJECTIVE

Squamous cell carcinomas comprise approximately 90% of all oral malignancies. There is a wide geographical variation in the incidence of oral cancer, with South and South East Asia (SSEA) accounting for almost two third of new cases. The prognosis of oral cancer is influenced by a vast array of factors including demographic, clinical, histopathological and molecular factors. The objective this review is to analyse the impact of histopathological features assessed in hematoxylin and eosin stained sections on the prognosis of OSCC.

MATERIALS AND METHODS

Medline and Scopus data base search was performed in order to identify related articles on histopathological parameters in predicting prognosis of oral squamous cell carcinoma. The primary emphasis is on the studies conducted in SSEA, with an accompanying comparison of their findings with those from research conducted in other parts of the world.

RESULTS

It has been shown that the number of studies conducted in SSEA is not proportionate to the high prevalence of Oral Cancer in the region. There is no significant difference between the findings from SSEA compared to the rest of the world. It is clearly shown that most histopathological parameters can be accurately used to predict nodal metastasis and prognosis.

CONCLUSIONS

Histopathological parameters can be used reliably in planning treatment of Oral cancer. Clinicians should combine clinical and histopathological parameters in drawing treatment plan for Oral Cancer.

Histopathological predictors of lymph node metastasis in oral cavity squamous cell carcinoma: a systematic review and meta-analysis

Objectives

Lymph node metastasis (LNM) is the most significant parameter affecting overall survival in patients with oral cavity squamous cell carcinomas (OCSCC). Elective neck dissection (END) is the standard of care in the early management of OCSCC with a depth of invasion (DOI) greater than 2-4 mm. However, most patients show no LNM in the final pathologic report, indicating overtreatment. Thus, more detailed indicators are needed to predict LNM in patients with OCSCC. In this study, we critically evaluate the existing literature about the risk of different histological parameters in estimating LNM.

Methods

A systematic review was conducted using PRISMA guidelines. PubMed, Web of Science, Cochrane, and Scopus were searched from inception to December 2023 to collect all relevant studies. Eligibility screening of records was performed, and data extraction from the selected studies was carried out independently. Inclusion in our systematic review necessitated the following prerequisites: Involvement of patients diagnosed with OCSCC, and examination of histological parameters related to lymph node metastasis in these studies. Exclusion criteria included animal studies, non-English articles, non-availability of full text, and unpublished data.

Results

We included 217 studies in our systematic review, of which 142 were eligible for the meta-analysis. DOI exceeding 4 mm exhibited higher risk for LNM [Risk ratio (RR) 2.18 (1.91-2.48), p<0.00001], as did perineural invasion (PNI) [RR 2.04 (1.77-2.34), p<0.00001], poorly differentiated tumors [RR 1.97 (1.61-2.42), p<0.00001], lymphovascular invasion (LVI) [RR 2.43 (2.12-2.78), p<0.00001], groups and single pattern of invasion [RR 2.47 (2.11-2.89), p<0.00001], high tumor budding [RR 2.65 (1.99-3.52), p<0.00001], tumor size over 4 cm [RR 1.76 (1.43-2.18), p<0.00001], tumor thickness beyond 4 mm [RR 2.72 (1.91-3.87), p<0.00001], involved or close margin [RR 1.73 (1.29-2.33), p = 0.0003], and T3 and T4 disease [RR 1.98 (1.62-2.41), p <0.00001].

Conclusion

Our results confirm the potential usefulness of many histopathological features in predicting LNM and highlight the promising results of others. Many of these parameters are not routinely incorporated into pathologic reports. Future studies must focus on applying these parameters to examine their validity in predicting the need for elective neck treatment.

Management of the neck in T1 and T2 buccal squamous cell carcinoma

Buccal squamous cell carcinoma (SCC) appears to behave more aggressively than other oral subsites, in particular with regards to regional disease at presentation and regional recurrence. Adequate management of the neck is of the utmost importance but is still the subject of debate. An international multicentre retrospective review of 101 patients treated for T1-T2 buccal SCC was performed. Twenty-four were staged clinical node positive (cN+) and underwent therapeutic neck dissection, while 77 were node negative (cN0), with 32 undergoing elective neck dissection (END), with an occult nodal metastasis rate of 28.1%. Depth of invasion (DOI) < 4 mm was associated with a significantly lower rate of cervical nodal metastasis (87.5% versus 12.5%; P = 0.033). END demonstrated a non-significantly lower regional recurrence rate compared to observation (6.3% versus 8.9%, P = 0.670). Regional recurrence was more common in pN+ (24%) and undissected cases (8.9%) than in pN0 patients (0%) (P = 0.011) and was associated with DOI > 5 mm (P = 0.002). Regional recurrence resulted in a reduction in survival (24 versus 93 months, P < 0.001). In the pT2cN0 group, END improved survival (123 versus 26 months, P = 0.009). It is suggested that END be performed in cT2N0 buccal SCC, particularly for tumours with DOI > 4 mm.

Prognostic and predictive biomarkers in head and neck cancer: something old, something new, something borrowed, something blue and a sixpence in your shoe

A biomarker is a measurable indicator of biological or pathological processes or the response to an exposure or intervention and is used to guide management decisions. In head and neck pathology, biomarkers are assessed by histological criteria and immunohistochemical and molecular studies. Surgical resection remains the mainstay of management of many head and neck malignancies. Adjuvant radiotherapy and/or systemic therapy may be administered depending on the presence of adverse prognostic factors identified on histopathological or immunohistochemical examination. In this review, we outline the clinically relevant prognostic and predictive factors in head and neck malignancies including conventionally recognised factors such as tumour size, depth of invasion, lymphovascular and perineural invasion and margin status as well as novel evolving factors such as recurrent genetic rearrangements and assessment of immune checkpoints. Practical issues are discussed to assist with recognising and reporting of these factors. A summary of useful tools such as structured pathology report formats is also included to assist with comprehensive reporting of all clinically relevant parameters, minimise risk and improve workflow efficiencies.

Management of clinically node-negative early-stage oral cancer: network meta-analysis of randomized clinical trials

The best treatments for the clinically node-negative (cN0) neck in early-stage oral squamous cell carcinoma (OSCC) patients are a subject of ongoing debate and there is no consensus. A network meta-analysis (NMA) of randomized clinical trials (RCTs) was conducted to determine the most effective treatment and to rank treatments based on their effectiveness. A systematic search was performed in accordance with the PRISMA guidelines to retrieve RCTs that compared therapeutic neck dissection (TND), sentinel lymph node biopsy (SLNB), and elective neck dissection (END). The outcomes analysed were overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), and nodal recurrence. Hazard ratios and risk ratios were calculated by direct meta-analysis and NMA. Ten RCTs with a total of 1858 patients were eligible for inclusion. Direct meta-analysis showed END to be superior to TND and comparable to SLNB. The NMA revealed no statistically significant difference between END and SLNB (very low quality evidence) regarding OS, DSS, DFS, and nodal recurrence. However, END was found to significantly improve OS and DFS, and reduce nodal recurrence when compared to TND (moderate quality evidence). END ranked as probably the top treatment option for maximizing OS and DSS, and reducing nodal recurrence in early-stage OSCC, followed by SLNB and TND. There was very low quality evidence supporting SLNB as non-inferior to END for patients with early-stage OSCC. This NMA yielded favourable results for the use of END (with moderate quality evidence) in early-stage OSCC patients, although excellent results have also been obtained with SLNB. However, data in the literature for SLNB are scarce, as this technique has not yet been formalized in many countries. There is a need to further explore SLNB for early-stage OSCC patients, as well as its value in detecting occult lymph node metastases on the contralateral side. More studies comparing morbidity, quality of life, and costs between the different management strategies for the clinically negative neck in early-stage OSCC patients are needed.

A Study of the Prognostic Factors for Late Cervical Lymph Node Metastasis and Distant Metastasis in Patients with cT1-2N0 Tongue Cancer

Background: Early-stage tongue cancer has a good prognosis in general; however, high-risk patients with late cervical lymph node and distant metastases have a poor prognosis. Elective neck dissection and postoperative chemoradiotherapy are considered for these patients, although no clear criteria have been identified for their evaluation. Methods: This retrospective observational study aimed to determine the predictive factors for late cervical lymph node and distant metastases in 102 patients with cT1-2N0 tongue cancer. The data regarding the demographic characteristics, as well as the depth of invasion, tumor budding, histological grade, and tumor-stromal ratio, among other things, were extracted from medical records. Results: We found that the potential lymph node metastasis rate was 27.5%. The significant clinical predictors of late cervical lymph node metastasis were the tumor thickness and endophytic growth pattern and the significant histopathological factors were poorly and moderately differentiated tumors and ≥3 tumor buds. In addition, the prognostic factors for distant metastasis included ≥4 lymph node metastases, ≥7 tumor budding, and moderate and poor tumor differentiation. Conclusions: The usefulness of tumor budding as a predictor of metastasis for tongue cancer was suggested. The findings of this study can help establish the criteria for evaluating the metastasis risk and prognosis of patients with tongue cancers.

Oral tumor heterogeneity, its implications for patient monitoring and designing anti-cancer strategies

Oral cancer tumors occur in the mouth and are mainly derived from oral mucosa linings. It is one of the most common and fatal malignant diseases worldwide. The intratumor heterogeneity (ITH) of oral cancerous tumor is vast, so it is challenging to study and interpret. Due to environmental selection pressures, ITH arises through diverse genetic, epigenetic, and metabolic alterations. The ITH also talks about peri-tumoral vascular/ lymphatic growth, perineural permeation, tumor necrosis, invasion, and clonal expansion/ the coexistence of multiple subclones in a single tumor. The heterogeneity offers tumors the adaptability to survive, induce growth/ metastasis, and, most importantly, escape antitumor therapy. Unfortunately, the ITH is prioritized less in determining disease pathology than the traditional TNM classifications or tumor grade. Understanding ITH is challenging, but with the advancement of technology, this ITH can be decoded. Tumor genomics, proteomics, metabolomics, and other modern analyses can provide vast information. This information in clinics can assist in understanding a tumor's severity and be used for diagnostic, prognostic, and therapeutic decision-making. Lastly, the oral tumor ITH can lead to individualized, targeted therapy strategies fighting against OC.

Predicting nodal metastases in squamous cell carcinoma of the oral tongue using artificial intelligence

OBJECTIVE

The presence of occult nodal metastases in patients with squamous cell carcinoma (SCC) of the oral tongue has implications for treatment. Upwards of 30% of patients will have occult nodal metastases, yet a significant number of patients undergo unnecessary neck dissection to confirm nodal status. This study sought to predict the presence of nodal metastases in patients with SCC of the oral tongue using a convolutional neural network (CNN) that analyzed visual histopathology from the primary tumor alone.

METHODS

Cases of SCC of the oral tongue were identified from the records of a single institution. Only patients with complete pathology data were included in the study. The primary tumors were randomized into 2 groups for training and testing, which was performed at 2 different levels of supervision. Board-certified pathologists annotated each slide. HALO-AI convolutional neural network and image software was used to perform training and testing. Receiver operator characteristic (ROC) curves and the Youden J statistic were used for primary analysis.

RESULTS

Eighty-nine cases of SCC of the oral tongue were included in the study. The best performing algorithm had a high level of supervision and a sensitivity of 65% and specificity of 86% when identifying nodal metastases. The area under the curve (AUC) of the ROC curve for this algorithm was 0.729.

CONCLUSION

A CNN can produce an algorithm that is able to predict nodal metastases in patients with squamous cell carcinoma of the oral tongue by analyzing the visual histopathology of the primary tumor alone.

Efficacy of radiological depth of invasion measurements on magnetic resonance images acquired at different magnetic field strengths and imaging sequences in predicting cervical lymph node metastasis and other outcomes in tongue cancer

OBJECTIVES

We investigated the correlation between magnetic resonance imaging (MRI) parameters and tumor pathological depth of invasion (pDOI), between pDOI and radiological DOI (rDOI), between rDOI and duration between biopsy and MRI, and between rDOI and duration between MRI and surgery to determine the efficacy of rDOI in identifying small lesions and other conditions.

STUDY DESIGN

We examined 36 adult patients who had been diagnosed histopathologically with cancer of the tongue and had undergone a glossectomy. Using 1.5 Tesla (T) and 3.0T MRI, we measured rDOI at the deepest infiltration point on 4 MRI sequences. We calculated the correlations between rDOI and the variables examined by Spearman rho analysis and evaluated the diagnostic performance of rDOI by receiver operating characteristic curve analysis.

RESULTS

Axial T2-weighted images using 1.5T MRI provided the closest approximation of pDOI. Although the correlation between rDOI and pDOI was significant, rDOI showed poor or acceptable discrimination in identifying small lesions and other conditions. There were no significant correlations between rDOI and the time between biopsy and MRI or between MRI and surgery.

CONCLUSIONS

The correlation between rDOI and pDOI is significant, but rDOI is ineffective in predicting malignancy and other conditions. Axial T2-weighted images using 1.5T MRI provide the closest approximation of pDOI.

Indications for sentinel lymph node biopsy in node-negative oral cancers

BACKGROUND

We aimed to define the indications for sentinel lymph node biopsy (SLNB), the third option for cervical treatment in oral cancer with negative cervical lymph nodes.

METHODS

The greatest depth of invasion (DOI) and long diameter (LD) of the primary site were used as exposures. SLN metastasis was considered the outcome.

RESULTS

In three trials conducted between 2009 and 2016, 158 patients were eligible and reassigned to this study group. The scatterplot based on the respective values of DOI and LD would eventually be divided into three sections. In cases of sections T1, T2, and T3, the proportions of SLN metastasis positivity were 21.3%, 35.3%, and 51.2%, respectively. In certain cases of T1 with 2 mm < DOI ≤ 5 mm and 8 mm < LD ≤ 20 mm, the proportion of SLN metastasis positivity was 40.9%.

CONCLUSIONS

SLNB-navigated or assisted neck dissection can be added as an effective procedure for N0 neck control.

Depth of Invasion, Lymphovascular Invasion, and Perineural Invasion as Predictors of Neck Node Metastasis in Early Oral Cavity Cancers

Aims

The present study examines the role of demographic and pathological features of primary tumours in predicting neck metastasis in early oral cavity cancers, which has been a matter of debate.

Methods

A single-centre, retrospective, institution review was conducted of all the patients presented to our centre from January 2014 to December 2021. Patient characteristics were compared between the two lymph node groups (lymph node positive and lymph node negative) and significant prognostic factors were determined.

Results

A total of 462 oral squamous cell carcinoma (OSCC) patients were included, 407 male and 55 female. Tobacco chewing (59.2%) was a major habit with buccal mucosa (49.5%) and tongue (44.8%) as primary sites. The majority of the patient's histology was of SCC (96.8%) with grade II (moderately differentiated, 74.5%). Univariate logistic regression analysis to predict lymph node metastasis showed pT size (< 0.001), LVI (< 0.001), and PNI (< 0.001) as significant tumor characteristics. On multivariate, pT size (OR-1.58, P - 0.0001) and LVI (OR-19.70, P - 0.0001) were reported to be statistically significant to predict lymph node metastasis.

Conclusion

Reporting and studying the clinico-pathological features of primary tumors can give vital information in predicting the neck node metastasis in OSCC patients.

WPOI-5: Accurately Identified at Intraoperative Consultation and Predictive of Occult Cervical Metastases

BACKGROUND

Frozen section analysis of oral cancer specimens is ideal for assessing margin distances and depth of invasion (DOI); the latter impacts intraoperative decisions regarding elective neck dissection (END). Here, we show that intraoperative determination of worst pattern of invasion (WPOI), specifically WPOI-5, has a high level of accuracy. This relates to our demonstration herein that WPOI-5 predicts occult cervical metastases (OCM) for pT1 oral squamous carcinoma (OSC).

METHODS

The presence of OCM was correlated with WPOI in 228 patients with primary T1/T2/cN0 OSC undergoing resection and END. Concordance between intraoperative and final pathology WPOI determination was assessed on 51 cases of OSC.

RESULTS

WPOI-5 predicts OCM in pT1 patients, compared with WPOI-4/WPOI-3 (p < 0.0001). Most pT1 WPOI-5 tumors had DOI of 4-5 mm (24/59 or 40.7%). Only two pT1 WPOI-5 tumors had DOI < 4 mm (3.0 and 3.5 mm). If END were performed in this pT1 cohort for all WPOI-5 OSC patients regardless of DOI, OR all OSC patients with DOI ≥ 4 mm regardless of WPOI, then no OCM would be missed (p = 0.017, 100% sensitivity, 29% specificity, 77% positive predictive value, 23% negative predictive value). With respect to intraoperative WPOI-5 determination, the accuracy, sensitivity, and specificity was 92.16, 73.33, and 100.0%, respectively.

CONCLUSIONS

DOI ≥ 4 mm is the dominant predictor of OCM. For the rare WPOI-5 OSC with DOI < 4 mm, it is reasonable to suggest that surgeons perform END. WPOI-5 may be accurately determined intraoperatively. As microscopic instruction is needed to accurately assess WPOI-5, a teaching link is included in this manuscript.

Surgery for maxillary oral squamous cell carcinoma: the effect of surgical resection margins and elective neck dissection on oncological outcomes

Maxillary oral squamous cell carcinoma (OSCC) is uncommon. Surgical resection is challenging due to the anatomy, and the role of elective neck dissection (END) is not well-defined. A retrospective cohort study of patients with maxillary OSCC treated with primary surgery between 2007 and 2019 was conducted. Primary tumours of sinonasal origin with extension into the oral cavity were excluded. Survival analysis was performed using Kaplan-Meier and Cox proportional hazards models. Sixty-seven patients were included; mean follow-up was 55 months. On univariate analysis, clear (≥5 mm) margins were associated with higher disease-free (68% vs 36%, P = 0.019) and overall survival (75% vs 36%, P = 0.004) than close/involved (<5 mm) margins. In clinically node-negative patients, the risk of occult cervical metastasis in tumours with depth of invasion (DOI) ≥ 3 mm and T2-4 tumours was 22% and 25%, respectively. END in these groups was associated with a lower rate of loco-regional recurrence (DOI ≥3 mm subgroup: 5% vs 38%, P = 0.029; T2-4 subgroup: 6% vs 50%, P = 0.028) and longer time to recurrence (DOI ≥3 mm subgroup: 119 months vs 96 months, P = 0.042; T2-4 subgroup: 117 months vs 56 months, P = 0.031) than observation of the neck. On multivariate analysis, close/involved margins were associated with an increased risk of overall mortality (hazard ratio 3.4, 95% confidence interval 1.0-11.3, P = 0.043) and disease recurrence (hazard ratio 2.8, 95% confidence interval 1.1-7.1, P = 0.031). In maxillary OSCC, a ≥ 5 mm histological margin should remain the goal of ablative surgery. END should be considered in tumours with DOI ≥ 3 mm.

Impact of depth of invasion on local recurrence in R0 resected node-negative oral tongue squamous cell carcinoma

BACKGROUND

This study evaluates the impact of depth of invasion (DOI) on local recurrence (LR) in node-negative oral tongue squamous cell carcinoma (SCC).

METHODS

Fifty-one patients were retrospectively reviewed from an institutional database. Patients were evaluated for local control (LC). Cox-proportional hazards modeling was used to calculate hazard ratios.

RESULTS

There were 84.3% T1/2 and 15.7% T3/4 classification tumors. The 3-year overall survival rate was 97.9%. Local failure rate was 5.7% with a 3-year LC of 93.6%. On Univariate analysis, increased hazard of LR was noted with each unit increase in DOI (HR 1.40, 95% CI 1.07-1.83, p = 0.014). Age, sex, T classification, margins ≥5 mm, lymphovascular invasion (LVI) and perineural invasion (PNI), and adjuvant treatment were not associated with LR. On Multivariate analysis, adjusting for age and adjuvant treatment, results for DOI remained significant (aHR 1.46, 95% CI 1.08-1.98, p = 0.013).

CONCLUSION

On evaluation of our institutional dataset increasing DOI was associated with increased hazard of local recurrence with oral tongue SCC.

The Roles of Exosomes in the Diagnose, Development and Therapeutic Resistance of Oral Squamous Cell Carcinoma

Oral cancer is one of the most common cancers worldwide, of which more than half of patients are diagnosed at a locally advanced stage with poor prognosis due to recurrence, metastasis and resistant to treatment. Thus, it is imperative to further explore the potential mechanism of development and drug resistance of oral cancer. Exosomes are small endosome-derived lipid nanoparticles that are released by cells. Since the cargoes of exosomes were inherited from their donor cells, the cargo profiles of exosomes can well recapitulate that of their donor cells. This is the theoretical basis of exosome-based liquid biopsy, providing a tool for early diagnosis of oral cancer. As an important intracellular bioactive cargo delivery vector, exosomes play a critical role in the development of oral cancer by transferring their cargoes to receipt cells. More importantly, recent studies have revealed that exosomes could induce therapy-resistance in oral cancer through multiple ways, including exosome-mediated drug efflux. In this review, we summarize and compare the role of exosomes in the diagnosis, development and therapy-resistant of oral cancer. We also highlight the clinical application of exosomes, and discuss the advantages and challenges of exosomes serving as predictive biomarker, therapy target and therapy vector in oral cancer.

Role of sentinel lymph node biopsy for oral squamous cell carcinoma: Current evidence and future challenges

Sentinel lymph node biopsy (SLNB) has been used across oncological specialties for prognostication, staging, and identification of occult nodal metastasis. Recent studies demonstrated the potential clinical utility of SLNB in oral cavity squamous cell carcinoma (OCSCC). Elective neck dissection is the current standard of care in early management of OCSCC with depth of invasion greater than 2-4 mm; however, majority of patients ultimately do not have nodal disease on final pathology. SLNB is an alternative procedure widely adopted in early cancer management in many oncological subspecialities. Several considerations such as depth of invasion, nodal mapping, histopathology methods, operator variability, postoperative complications, and advancement in preoperative and intraoperative imaging technology can guide the appropriate application to SLNB in OCSCC. The aim of this review is to discuss the current evidence for SLNB in the treatment of early stage OCSCC, imaging technologies that support SLNB procedures, and studies that are currently underway.

Prognostic factors in oral cancer surgery - results from a UK tertiary centre

INTRODUCTION

Oral cancer surgery is complicated by the diverse nature of clinical and histopathological presentations that occur. Current National guidance recognises the significant role that surgical margin status plays in the overall survival of patients. Many other histopathological factors influence patient survival, the importance of which varies between the literature.

MATERIALS AND METHODS

In this prospective longitudinal study, all patients diagnosed with squamous cell carcinoma who had primary surgical treatment under general anaesthesia were included. Surgery was performed by one surgical team within this tertiary referral centre. Patients were followed up for a maximum of 7 years following their surgery.

RESULTS

A total of 250 patients were included from 2015 to 2022. Patients were 61.44 years old (SD 13.23) at diagnosis, and 56.4% were male (n = 141). Pathology was mainly pT1 (39.1%) and the most common sites were the border of tongue (31.2%) and floor of mouth (18.8%). 43.4% of patients had clear surgical margins, with overall survival being significantly associated with margin status (p = 0.0079). Extra-capsular spread was significantly associated with higher risk of death from metastatic head and neck cancer (p = 0.014), whereas presence of high-grade dysplasia at surgical margins and depth of invasion of tumour were not.

CONCLUSION

This study has reinforced the importance of surgical margin clearance and as such the development of intra-operative techniques to ensure this is imperative. The significance of extra-capsular spread in survival has also been demonstrated. Discussion regarding the current deficiency in accurate pre-operative diagnostic methods for extra capsular spread is covered.

Influence of Site, Size, Depth of Invasion and Histologic Grading on the Occurrence of Cervical Level IIb Metastasis and Extranodal Extension in Clinically N0 Neck of Patients with OSCC: A Single Center Retrospective Analysis

Background

Depth of Invasion ≥ 4 mm, T stage and primary site with more than 20% chances for occult metastasis are currently the accepted indications for elective neck dissection. Nodal metastasis decreases survival by 50%. ENE further reduces the prognosis. Dissection of level IIb lymph nodes in clinically N0 neck does not improve survival.

Methods

A total of 320 patients were evaluated. Binary and multiple logistic regression and chi-square test were used for data analysis. ROC curve with Youden's J index was used to set up a cutoff value for DOI. The predictor variables were site, size, grading and depth of invasion of primary tumor. Incidence of level IIb metastasis and ENE were the outcomes.

Results

The study revealed a significant association and risk stratification between primary tumor characteristics with the occurrence of ENE. The cutoff value for DOI predicting ENE was 12.5 mm. Tumors of the oral tongue were an independent risk factor for level IIb metastasis.

Discussion

Size of primary tumor, DOI, tumors of the mandibular alveolus and poor grading are independent risk factors for ENE. Isolated metastasis to level IIb rarely occurs in the absence of concomitant level IIa metastasis. Size, DOI and grading were significantly associated with level IIb metastasis. However, only tumors of the oral tongue were independent risk factor.

Early-Stage Oral Tongue Squamous Cell Carcinoma and a Positive Sentinel Lymph Node Biopsy: Description of a Prognostic Correlation between Pre-Treatment Inflammatory Biomarkers, the Depth of Invasion and the Worst Pattern of Invasion

The aim of this study was to investigate the correlation between pre-treatment inflammatory biomarkers and the post-operative depth of invasion (DOI) and worst pattern of invasion (WPOI) in early-stage oral tongue squamous cell carcinoma (OTSCC) by means of positive sentinel lymph node biopsy (SLNB). A retrospective analysis of patients affected by cN0 T1-T2 OTSCC who had undergone an SLNB at the National Cancer Institute of Naples was performed. The patients were studied using an evaluation of the pre-treatment neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammatory index (SII), and a histopathological analysis of the DOI and WPOI. The statistical analysis showed that among the prognostic biomarkers, the NLR was a significant predictor of high WPOI values (p = 0.002). The cut-off NLR value was 2.52 with a probability of developing a positive sentinel lymph node biopsy (SLNB) of 30.3%. In contrast, the DOI value was 5.20 with a probability of developing a positive SLNB of 31.82%. Regarding the WPOI, increasing the WPOI class increased the likelihood of a positive SLNB occurrence, and a positive significant correlation was found between the WPOI and SLNB (Csp = 0.342; p < 0.001). Pre-treatment NLR, together with post-surgical DOI and WPOI, can be a reliable predictor of occult neck metastasis in patients affected by early-stage OTSCC with a clinically negative neck. Further prospective studies with a larger series will be needed to confirm the results obtained and to better define the NLR, WPOI and DOI cut-off values in order for elective neck dissection to be recommended in relation to a clinically negative neck.

High-Frequency Intraoral Ultrasound for Preoperative Assessment of Depth of Invasion for Early Tongue Squamous Cell Carcinoma: Radiological-Pathological Correlations

The eighth edition of the TNM classification officially introduced "depth of invasion" (DOI) as a criterion for determining the T stage in tongue squamous cell carcinoma. The DOI is a well-known independent risk factor for nodal metastases. In fact, several experts strongly suggest elective neck dissection for tongue cancer with a DOI > 4 mm due to the high risk of early and occult nodal metastases. Imaging plays a pivotal role in preoperative assessments of the DOI and, hence, in planning the surgical approach. Intraoral ultrasound (IOUS) has been proposed for early-stage SCC of the oral tongue as an alternative to magnetic resonance imaging (MRI) for local staging. The aim of this work is to investigate the accuracy of IOUS in the assessment of the DOI in early oral SCC (CIS, pT1, and pT2). A total of 41 patients with tongue SCCs (CIS-T2) underwent a preoperative high-frequency IOUS. An IOUS was performed using a small-size, high-frequency hockey-stick linear probe. The ultrasonographic DOI (usDOI) was retrospectively compared to the pathological DOI (pDOI) as the standard reference. In patients who underwent a preoperative MRI, their usDOI, magnetic resonance DOI (mriDOI), and pDOI were compared. Specificity and sensitivity for the IOUS to predict a pDOI > 4 mm and to differentiate invasive and noninvasive tumors were also evaluated. A high correlation was found between the pDOI and usDOI, pDOI and mriDOI, and usDOI and mriDOI (Spearman's ρ = 0.84, p < 0.0001, Spearman's ρ = 0.79, p < 0.0001, and Spearman's ρ = 0.91, p < 0.0001, respectively). A Bland-Altman plot showed a high agreement between the usDOI and pDOI, even though a mean systematic error was found between the usDOI and pDOI (0.7 mm), mriDOI and pDOI (1.6 mm), and usDOI and mriDOI (-0.7 mm). The IOUS was accurate at determining the T stage (p < 0.0001). The sensitivity and specificity for the IOUS to predict a pDOI ≥4 mm were 92.31% and 82.14%, respectively, with an AUC of 0.87 (p < 0.0001). The specificity, sensitivity, negative predictive value (NPV), and positive predictive value (PPV) for the IOUS to predict an invasive cancer were 100%, 94.7%, 60%, and 100%, respectively. The AUC was 0.8 (95% CI 0.646-0.908, p < 0.0001). The IOUS was accurate in a preoperative assessment of a pDOI and T stage, and can be proposed as an alternative to MRI in the preoperative staging of tongue SCC.

The Applications and Potential Developments of Ultrasound in Oral Cancer Management

Oral cancer is endemic and causes a great burden in Southern Asia. It is preferably treated by surgery with/without adjuvant radiotherapy (RT) or chemoradiation therapy, depending on the stage of the disease. Close or positive resection margin and cervical lymph node (LN) metastasis are important prognostic factors that have been presented to be related to undesirable locoregional recurrence and poor survival. Ultrasound (US) is a simple, noninvasive, time-saving, and inexpensive diagnostic modality. It can depict soft tissues very clearly without the risk of radiation exposure. Additionally, it is real-time and continuous image is demonstrated during the exam. Furthermore, the clinician can perform US-guided fine needle aspiration (FNA) or core needle biopsy (CNB) at the same time. US with/without US-guided FNA/CNB is reported to be of value in determining tumor thickness (TT), depth of invasion (DOI), and cervical LN metastasis, and in aiding the staging of oral cancer. DOI has a relevant prognostic value as reported in the eighth edition of the American Joint Committee on Cancer staging of oral cancer. In the present review, we describe the clinical applications of US in oral cancer management in different phases and potential applications in the future. In the pretreatment and surgical phase, US can be used to evaluate TT/DOI and surgical margins of oral cancer in vivo and ex vivo. The prediction of a malignant cervical LN (nodal metastasis) by the US-based prediction model can guide the necessity of FNA/CNB and elective neck dissection in clinical early-stage oral cancer. In the posttreatment surveillance phase, US with/without US-guided FNA or CNB is helpful in the detection of nodal persistence or LN recurrence, and can assess the possibility and extent of carotid artery stenosis after irradiation therapy. Both US elastography and US swallowing assessment are potentially helpful to the management of oral cancer.

Protocol for a multicentre, prospective observational study of elective neck dissection for clinically node-negative oral tongue squamous cell carcinoma (END-TC study)

INTRODUCTION

In early-stage oral tongue squamous cell carcinoma (OTSCC), elective neck dissection (END) is recommended when occult lymph node metastasis is suspected; however, there is no unanimous consensus on the risks and benefits of END in such cases. The management of clinically node-negative (cN0) OTSCC remains controversial. This study, therefore, aimed to evaluate the efficacy of END and its impact on the quality of life (QoL) of patients with cN0 OTSCC.

METHODS AND ANALYSIS

This is a prospective, multicentre, nonrandomised observational study. The choice of whether to perform END at the same time as resection of the primary tumour is based on institutional policy and patient preference. The primary endpoint of this study is 3-year overall survival. The secondary endpoints are 3-year disease-specific survival, 3-year relapse-free survival and the impact on patient QoL. Propensity score-matching analysis will be performed to reduce selection bias.

ETHICS AND DISSEMINATION

This study was approved by the Clinical Research Review Board of the Nagasaki University. The protocol of this study was registered at the University Hospital Medical Information Network Clinical Trials Registry. The datasets generated during the current study will be available from the corresponding author on reasonable request. The results will be disseminated internationally, through scientific and professional conferences and in peer-reviewed medical journals.

TRIAL REGISTRATION NUMBER

UMIN000027875.

Prognostic and clinicopathological significance of cytocapsular tubes in oral squamous cell carcinoma

BACKGROUND

Cytocapsular tubes (CTs) provide membranous channels for cancer cells interconnection and multidirectional locomotion, which facilitate cancer cell transportation and metastasis. However, the clinicopathological significance of CTs has not been documented in oral squamous cell carcinoma (OSCC). Herein, we aimed to identify CTs and assess their clinicopathological significance in OSCC.

METHODS

Operetta CLS™ high-content analysis system was used to detect the CTs originated from OSCC cells cultured in a 3D Matrigel matrix. Then, pan-cadherin and γ-actin immunostaining were performed to identify CTs in 4NQO-induced murine OSCC tissues, OSCC xenografts and 88 human primary OSCC samples. Finally, the prognostic value and clinicopathological significance of CTs in OSCC were further examined by using the Kaplan-Meier method and Cox regression analysis.

RESULTS

CTs were observed in OSCC cells in a 3D Matrigel matrix. In vivo, CTs were frequently identified in 4NQO-induced murine OSCC tissues, OSCC xenografts and human primary OSCC samples. CTs density was significantly associated with T stage, lymph node metastasis, differentiation, invasive depth, tumor budding, TNM stage and tumor recurrence. Importantly, the high-CTs density indicated a decreased overall survival (OS) and progression-free survival (PFS) in OSCC patients. Cox regression models showed that CTs could serve as a prognostic factor for OS and PFS.

CONCLUSION

CTs, which are correlated with the cell migration and invasion, can be readily identified in OSCC and appear to be a novel biomarker for patients at risk of metastasis.

Tongue cancer following hematopoietic cell transplantation for Fanconi anemia

OBJECTIVES

The aim of this retrospective study was to determine the incidence and the clinical outcome of tongue cancer (TC) in patients affected by Fanconi anemia (FA) who received an allogeneic hematopoietic cell transplantation (HCT).

MATERIALS AND METHODS

The patient database from the Bone Marrow Transplant Center of Pescara was reviewed to enroll FA patients. Patients', donors', HCT's, and screening's data were collected as well to look for the incidence and the treatment of TC.

RESULTS

Twelve patients affected by FA were identified. Three patients died for transplant-related causes. Five of nine surviving patients were diagnosed with TC at a median of 21.7 years since transplantation and at a median age of 32.10 years. Interestingly, no patient manifested graft-versus-host-disease (GvHD). The 28-year cumulative incidence function of TC was 46.9% (95% CI, 36.9-56.9%). Two patients were treated with chemotherapy alone, two patients were treated with surgery alone, and one with surgery followed by chemotherapy. Overall, 4 patients with TC showed a clinical course characterized by a marked aggressiveness of the tumor disease which led to death due to cancer progression between 2 and 13 months. One patient is surviving 8 months after diagnosis of TC.

CONCLUSIONS

Our study confirms the high incidence of tumors and in particular tongue tumors in allotransplanted FA patients. A careful screening has to be life-long maintained.

CLINICAL RELEVANCE

Considering the rarity of FA and the frailty of FA patients, this study may add important information for the cancer management of these patients.

Variability in Depth of Invasion Measurements in Carcinomas of the Oral Cavity and the Effect on Pathologic Tumor Staging

Depth of invasion (DOI) was added to the staging criteria for carcinoma of the lip and oral cavity in the 8th edition of the American Joint Committee on Cancer Staging Manual (AJCC8). However, there are multiple practical challenges to obtaining an accurate DOI measurement with limited data regarding interobserver variability in DOI measurement. The aim of this study was to investigate interobserver variability in DOI measurement and its effect on tumor stage. We performed an electronic medical record search for excisions of squamous cell carcinoma of the oral cavity between January 1, 2010 and December 25, 2017. All slides containing significant tumor were selected for independent blinded DOI measurement by four head and neck pathologists per AJCC8 guidelines. Pathologic stage was assigned in conjunction with reported tumor greatest dimension. Observers recorded the slide used for measurement and potential issues limiting assessment of DOI. Results were compared for reproducibility in DOI and tumor stage using intraclass correlation coefficient (ICC) analysis. A total of 167 cases of oral squamous cell carcinoma with available slides were included. The ICC score for DOI between observers was 0.91339 (> 0.9 considered excellent). Only 7.2% of cases had uniform DOI amongst observers. Increasing overall tumor size and average DOI correlated with increasing range in DOI amongst observers. Differences in DOI resulted in differences in pathologic tumor staging (pT) for 15% of tumors. Use of different slides for DOI measurements was significantly associated with different pT staging. In contrast, ulceration and exophytic growth did not correlate with higher DOI or pT variability. Despite the excellent ICC score, differences in DOI measurement resulted in variable pT staging for a considerable number of cases. We therefore recommend consensus for DOI in at least some cases in which potential differences in DOI could alter pT stage assignment.

Neck Management in cT1N0 Tongue Squamous Cell Carcinoma as Determined by Sonographic Depth of Invasion

Objectives

To compare the oncologic outcomes in patients with cT1N0 tongue squamous cell carcinoma (SCC) who underwent different neck management strategies stratified by sonographic depth of invasion (DOI).

Methods

The included patients were retrospectively enrolled, and divided into two groups: observation (OBS) and elective neck dissection (END). The regional control (RC) and disease-specific survival (DSS) rates were compared and stratified by sonographic DOI.

Results

The mean sonographic and pathologic DOIs were 3.8 and 3.7 mm, respectively; the two DOIs were significantly correlated (Spearman correlation coefficient 0.974. p <0.001). In patients with sonographic DOI <4.0 mm, the 5-year RC rates were 73 and 89% in the OBS and END groups, respectively, and were not significantly different. However, in patients with sonographic DOI ≥4.0 mm, the 5-year RC rate was significantly different between the OBS (57%) and END (80%) groups (p = 0.031). In patients with sonographic DOI <4.0 mm, the 5-year DSS rates were 79 and 89% in OBS and END groups, respectively, and were not significantly different. However, in patients with sonographic DOI ≥4.0 mm, the 5-year DSS rate was significantly different between the OBS (67%) and END (86%) groups (p = 0.033).

Conclusions

Sonographic DOI was notably correlated with pathologic DOI. Moreover, there was a significant survival difference between the OBS and END groups in cT1N0 tongue SCC patients with sonographic DOI ≥4.0 mm but not in those with sonographic DOI <4.0 mm. Our study provides a useful method to aid decision-making in the clinical setting for this patient group.

Depth of Invasion as a Predictor of Cervical Nodal Metastasis of Oral Tongue Squamous Cell Carcinoma: Findings From a Tertiary Care Center in Pakistan

Background and objective

Cervical lymph node metastasis has a significant impact on the survival of patients with oral cavity tumors. The rate of occult neck node metastasis is reported to range from 20 to 40%. The depth of invasion (DOI) has been incorporated in the eighth edition of the American Joint Commission on Cancer (AJCC) staging manual and is an important predictor of cervical lymph node metastasis. In this study, we aimed to identify the occult neck node metastasis rate in early oral tongue squamous cell carcinoma (OTSCC) and correlate it with the DOI.

Methods

A retrospective review of all patients presenting to our facility with early-stage OTSCC was performed. Patients with tumor size of ≤4 cm and who underwent elective neck dissection at the time of surgery were included. The study outcomes were the rates of occult neck metastases in T1 and T2 OTSCC and their correlation with the DOI.

Results

There were 80 patients in total. Occult neck node metastases were seen in 29 (36.25%) patients. Patients with a DOI >5 mm were 1.41 times more likely to have occult neck node metastasis than those with a DOI ≤5 mm.

Conclusion

Occult neck node metastasis is significantly associated with the DOI. The risk of neck metastasis is higher in patients with a DOI >5 mm.

Experimental study on needle insertion force to minimize tissue deformation in tongue tissue

This study reports on the effects of insertion velocity, needle tip geometry and needle diameter on tissue deformation and maximum insertion force. Moreover, the effect of multiple insertions with the same needle on the maximum insertion force is reported. The tissue deformation and maximum insertion force strongly depend on the insertion velocity and the tip geometry. No correlation was found between the outer diameter and the maximum insertion force for small needles (30G - 32G). The endurance experiments showed no remarkable difference in the maximum insertion force during 100 insertions.

Pretreatment Blood Markers in the Prediction of Occult Neck Metastasis: A 10-Year Retrospective Study

Introduction

The purpose of this study was to clarify the role of inflammatory blood markers in the management of early-stage (T1-T2) oral squamous cell carcinoma (OSCC) of the tongue in patients with a clinically negative neck. 

Materials and methods

We undertook a retrospective chart review of 102 patients with early-stage OSCC of the tongue, subjected to tumor resection and elective neck dissection. Based on postsurgical histopathological examination results, we divided our cohort into pN+ and pN0 groups. Afterwards, we analyzed the role of pretreatment inflammatory blood markers in predicting occult neck metastasis. We also evaluated neutrophil-lymphocyte ratio (NLR) association with the depth of invasion (DOI) of the primary tumor.

Results

We found a significant association of NLR (p=0.001) and monocyte-lymphocyte ratio (p=0.011) with neck status on univariate analysis. Multivariate analysis showed that only NLR (p=0.02) was an independent risk factor for occult metastasis among inflammatory blood markers. Receiver Operating Characteristic curve analysis and Younden’s Index determined the NLR value of 2.96 as the most adequate cut-off value for neck status prediction. NLR values of pretreatment workup also had a significant association with the DOI of the primary tumor (p=0.018).

Conclusion

Our study supports the role of pretreatment NLR in predicting occult neck metastasis in early-stage OSCC of the tongue. It also sheds some light over the potential of NLR as a predictor of the primary tumor’s DOI.

Evaluation of Depth of Invasion in Oral Squamous Cell Carcinoma with Ultra-High Frequency Ultrasound: A Preliminary Study

Intraoral ultrasonography has been widely employed for the preoperative assessment of tumor margins due to its capability to evaluate depth of invasion (DOI) and tumor thickness (TT). Recently, a novel ultrasonographic technique, ultra-high frequency ultrasound (UHFUS) has been increasingly applied to the study of oral lesions. This study evaluates the potential application of intraoral UHFUS to assess DOI and TT parameters of oral squamous cell carcinoma (OSCC) lesions. Patients clinically suspected of OSCC lesions were enrolled and underwent an intraoral UHFUS examination preoperatively. The parameters of TT, DOI, echogenicity, and vascularization were assessed. The parameters of TT and DOI as evaluated by means of UHFUS were compared to histology, which was set as the benchmark. Ten patients in total were enrolled. UHFUS-based DOI and TT measurements were found to positively correlate with histology (p < 0.05), although UHFUS provided a slight overestimation of DOI. No differences were found in terms of echogenicity or vascularization depending on the site of the lesion. According to these preliminary results, UHFUS could support the preoperative assessment of TT and DOI, potentially enhancing the clinical evaluation of OSCC.

The Potential of MET Immunoreactivity for Prediction of Lymph Node Metastasis in Early Oral Tongue Squamous Cell Carcinoma

Objective

MET positivity is independently associated with survival in oral squamous cell carcinoma (OSCC). Since MET is a known orchestrator of invasive tumor growth, we investigated its association with LNM in early oral tongue squamous cell carcinoma (OTSCC). As it is recommended by the NCCN to use tumor depth of invasion (DOI) in making decisions on elective neck dissection (END), the results obtained for MET positivity were aligned with those for DOI > 4 mm. The cutoff value used in our institution.

Methods

Tumor samples from patients who underwent primary tumor resection and neck dissection between 1995 and 2013, were collected from the archives of the Leiden and Erasmus University Medical Center. Immunohistochemistry with D1C2 was performed to identify MET negative (< 10% uniform positivity) and MET positive (≥ 10% uniform positivity) cancers. ROC curve analysis and the Chi-squared test were used to investigate the association of MET positivity with LNM (pN+ and occult). Binary logistic regression was used to investigate the association of MET positivity with LNM.

Results

Forty-five (44.1%) of the 102 cancers were MET positive. Ninety were cN0 of which 20 were pN+ (occult metastasis). The remaining 12 cancers were cN+, of which 10 were proven pN+ and 2 were pN0. MET positivity was associated with LNM with a positive predictive value (PPV) of 44.4% and a negative predictive value (NPV) of 82.5% for pN+. For the occult group, the PPV was 36.8% and the NPV was 88.5%. Regression analysis showed that MET positivity is associated with pN+ and occult LNM (p-value < 0.05).

Conclusion

MET positivity is significantly associated with LNM in early OTSCC, outperforming DOI. The added value of MET positivity could be in the preoperative setting when END is being considered during the initial surgery. For cases with DOI ≤ 4 mm, MET positivity could aid in the clinical decision whether regular follow-up, watchful waiting, or END is more appropriate. Realizing that these preliminary results need to be independently validated in a larger patient cohort, we believe that MET positivity could be of added value in the decision making on END in early OTSCC.