Cumulative incidence of neck recurrence with increasing depth of invasion

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.

Identifying factors related to delayed neck metastasis after surgical treatment in patients with oral squamous cell carcinoma

BACKGROUND

General treatment of oral squamous cell carcinoma (OSCC) is surgical treatment with or without neck dissection. Although the incidence of delayed neck metastasis is rare, it may occur after the surgery and is known to be the most important factor in the prognosis. The purpose of is study is to evaluate the clinical and histopathological factors associated with delayed neck metastasis case among patients.

METHODS

A total of 195 patients who underwent surgical treatment for OSCC from 2016 to 2022 were investigated. Among them, delayed neck metastasis (DNM) was analyzed. The criterion for delayed neck metastasis was a newly developed neck lesion after the primary operation without neck dissection in cN0 necks. To identify the correlation between prognostic factors and the incidence of delayed neck metastasis, χ2 analysis with phi correlation and Cramer's V test was performed. Cumulative survival rates (CRS) were compared between the groups with the incidence of DNM and without DNM. Also, the log rank test for CSR and Cox proportional hazard model was analyzed to estimate the significance of the CSR and confirm the correlations between prognostic factors and DNM.

RESULT

Among 195 patients, 14 were discovered to have DNM. The primary tumor locations were the tongue (n = 5), floor of the mouth (n = 2), mandibular gingiva (n = 1), maxillary gingiva (n = 4), retromolartrigone (n = 1), and buccal mucosa (n = 2) each. The cases consisted of TNM stage I (n = 1), stage II (n = 3), stage III (n = 3), and stage IV (n = 8), respectively. The result of the χ2 analysis identified a correlation between positive neck (p = 0.01), depth of invasion (p = 0.09), radiation therapy (p = 0.003), and DNM. Groups without DNM showed better prognosis compared to groups with DNM. Regarding positive neck, depth of invasion, and radiation therapy, only depth of invasion showed significance in CSR analysis.

CONCLUSION

DNM after surgical treatment of OSCC is a rare event, and few were found in a review of the literature. Also, many prognostic factors have been suggested but controversial. However, in our study, some prognostic factors have been identified to have a significant correlation with the incidence of DNM, and analysis of such factors provides important information predicting neck metastasis and the prognosis.

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.

When should patients with T1N0 oral squamous cell carcinoma be considered for elective neck dissection?

AIMS

To identify adverse pathological features (APF) predicting nodal failure in clinically node negative T1 oral squamous cell carcinoma (OSCC).

METHODOLOGY

This study evaluated patients with T1N0 (≤5 mm depth of invasion (DOI) and ≤2 cm diameter) oral cancers from a prospectively maintained database between 1988 and 2020. All patients underwent surgical excision of the primary lesion without neck dissection. Patients underwent three monthly clinical surveillance and salvage neck dissection was performed if nodal relapse was diagnosed.

RESULTS

Overall, 141 patients were included. Nodal relapse was reported in 16/141 (11.3%) patients. Factors impacting regional recurrence-free survival were DOI ≥3 mm (HR: 2.4, P < 0.001), maximum tumour diameter ≥12 mm (HR: 1.1, P = 0.009), perineural invasion (PNI) (HR 7.5, P = 0.002) and poor differentiation (HR 5.3, P = 0.01). Rates of nodal relapse increased from 2% amongst patients with no APFs to 100% for those with four APFs. Patients with two or more APFs had significantly poorer 5-year regional recurrence-free survival (94.8% vs. 56.3%, P < 0.001).

CONCLUSION

Patients with T1N0 OSCC with two or more APFs (DOI ≥3 mm, diameter ≥12 mm, PNI or poor differentiations) should be considered for elective neck dissection.

Margin distance in oral tongue cancer surgery: A systematic review of survival and recurrence outcomes

The status of resection margins is a proxy for the completeness of resection in oral tongue cancer surgery and is therefore a useful predictor for post-operative prognosis. Historically, a margin distance of 5 mm or greater has been deemed a negative margin and is believed to yield a benefit in terms of control and survival. To summarize the literature more completely on this topic, we conducted a systematic review that examines radial margin distance and its relationship to disease control and survival in oral tongue cancer. Our review includes 34 studies which reported survival and/or recurrence outcomes for oral tongue cancer patients based on margin status. Most studies reported outcomes for the 5 mm margin, while the minority utilized other margin cutoffs. For the 5 mm cutoff, outcomes were generally favorable regarding survival and recurrence outcomes. Nonetheless, studies using 4 mm, 3.3 mm, and 10 mm cutoffs also found favorable survival and recurrence outcomes; however, these are a minority of the included studies.

Impact of worst pattern of invasion on prognosis of oral squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVE

The relationship between the worst pattern of invasion (WPOI) and the prognosis of oral squamous cell carcinoma (OSCC) remains controversial. This systematic review and meta-analysis was performed to determine the impact of the WPOI on the prognosis of OSCC.

METHODS

Studies from six databases were assessed for quality using the Newcastle-Ottawa Scale, and data were analyzed using Stata software.

RESULTS

Eighteen studies involving 3954 patients showed that patients with a WPOI of 4 to 5 had significantly worse overall survival, disease-specific survival, and disease-free survival than patients with a WPOI of 1 to 3. Significant associations of the WPOI with locoregional recurrence and mortality were found.

CONCLUSION

A higher WPOI was significantly associated with a worse prognosis of OSCC across various outcomes. Incorporating the WPOI into standard histopathological assessments may guide personalized treatments and improve outcomes.

A prediction model of nodal metastasis in cN0 oral squamous cell carcinoma using metabolic and pathological variables

BACKGROUND

The efficacy of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) Positron Emission Tomography/Computed Tomography(PET/CT) in evaluating the neck status in clinically node-negative (cN0) oral squamous cell carcinoma(OSCC) patients was still unsatisfying. We tried to develop a prediction model for nodal metastasis in cN0 OSCC patients by using metabolic and pathological variables.

METHODS

Consecutive cN0 OSCC patients with preoperative ¹⁸F-FDG PET/CT, subsequent surgical resection of primary tumor and neck dissection were included. Ninety-five patients who underwent PET/CT scanning in Shanghai ninth people's hospital were identified as training cohort, and another 46 patients who imaged in Shanghai Universal Medical Imaging Diagnostic Center were selected as validation cohort. Nodal-status-related variables in the training cohort were selected by multivariable regression after using the least absolute shrinkage and selection operator (LASSO). A nomogram was constructed with significant variables for the risk prediction of nodal metastasis. Finally, nomogram performance was determined by its discrimination, calibration, and clinical usefulness.

RESULTS

Nodal maximum standardized uptake value(nodal SUVmax) and pathological T stage were selected as significant variables. A prediction model incorporating the two variables was used to plot a nomogram. The area under the curve was 0.871(Standard Error [SE], 0.035; 95% Confidence Interval [CI], 0.787-0.931) in the training cohort, and 0.809(SE, 0.069; 95% CI, 0.666-0.910) in the validation cohort, with good calibration demonstrated.

CONCLUSIONS

A prediction model incorporates metabolic and pathological variables has good performance for predicting nodal metastasis in cN0 OSCC patients. However, further studies with large populations are needed to verify our findings.

Comparison of transoral and combined approach for surgical treatment of moderately advanced tongue and floor of the mouth cancer

Introduction. Surgical approach for oral cancer treatment is one of the key factors that determines oncologic effectiveness, risk of postoperative complications, need for reconstructive methods etc. Currently, there exists lack of strict criteria for using one or another approaches based on the sound scientific evidence for a primary tumor of given depth of invasion.

Aim. The aim of the study is a retrospective comparative analysis of oncologic efficiency of transoral and combined approaches for surgical treatment of tongue and floor of the mouth moderately advanced carcinoma.

Materials and methods. 75 patients aged between 30 and 80 years with tongue and floor of the mouth squamous cell carcinoma with depth of invasion from 10 to 20 mm were included into the study. In 29 cases the tumor was resected transorally (Group 1), in 45 – via combined approach (Group 2). Group 2 patients had more advanced tumors both locally and regionally. 13 patients of Group 1 and 27 patients of Group 2 underwent adjuvant radiotherapy. The following parameters were used for comparative analysis: the rate of local and regional recurrence, locoregional control, the rate of distant metastasis and Kaplan–Meyer overall survival.

Results. Mean follow up was 33.77 ± 27.72 months (range 14–115 months). The rate of local and regional recurrence was higher in Group 2 (20 % vs 10.3 % and 22.2 % vs 17.2 % respectively). Locoregional control was better in Group 1 (72.4 % vs 62.2 %). The difference for neither of the above-mentioned parameters did not reach statistical significance. Median survival was statistically significantly better in Group 1: 66 ± 17.42 months vs 23 ± 3.85 months (p = 0.030). Poorer treatment results in Group 2 can be explained by a higher proportion of patients with more advanced tumors in this group.

Conclusion. The results of the present study do not allow to conclude that combined approach has oncologic advantage over less aggressive transoral approach for tumors with depth of invasion from 10 to 20 mm. It is questionable to recommend the combined approach as a universal one for lesions with such a stage of local invasiveness.

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.

Clinical and Prognostic Significance of the Eighth Edition Oral Cancer Staging System

Objectives: The most notable changes in the eighth edition of the AJCC Cancer Staging System include incorporating the depth of invasion (DOI) into T staging and extranodal extension (ENE) into N staging. In this study, we retrospectively assessed the prognostic and clinical implications of the eighth TNM staging system. Materials and Methods: Patients with Oral Squamous Cell Carcinoma (OSCC) who were treated surgically between 2010 and 2017 were retrospectively reviewed. Tumors were first staged according to the seventh edition and restaged using the eighth edition. The prognostic value of the resultant upstaging was evaluated. Results: Integrating the DOI into the T classification resulted in the upstaging of 65 patients, whereas incorporating ENE into the N staging resulted in the upstaging of 18 patients (p < 0.001). Upstaging due to DOI integration had no significant effect on OS or DSS (p > 0.05). Conclusion: Our results demonstrate the importance of incorporating ENE into nodal staging and considering adjuvant therapy when ENE is present.

Adding Concomitant Chemotherapy to Postoperative Radiotherapy in Oral Cavity Carcinoma with Minor Risk Factors: Systematic Review of the Literature and Meta-Analysis

When presenting with major pathological risk factors, adjuvant radio-chemotherapy for oral cavity cancers (OCC) is recommended, but the addition of chemotherapy to radiotherapy (POCRT) when only minor pathological risk factors are present is controversial. A systematic review following the PICO-PRISMA methodology (PROSPERO registration ID: CRD42021267498) was conducted using the PubMed, Embase, and Cochrane libraries. Studies assessing outcomes of POCRT in patients with solely minor risk factors (perineural invasion or lymph vascular invasion; pN1 single; DOI ≥ 5 mm; close margin < 2−5 mm; node-positive level IV or V; pT3 or pT4; multiple lymph nodes without ENE) were evaluated. A meta-analysis technique with a single-arm study was performed. Radiotherapy was combined with chemotherapy in all studies. One study only included patients treated with POCRT. In the other 12 studies, patients were treated with only PORT (12,883 patients) and with POCRT (10,663 patients). Among the patients treated with POCRT, the pooled 3 year OS rate was 72.9% (95%CI: 65.5−79.2%); the pooled 3 year DFS was 70.9% (95%CI: 48.8−86.2%); and the pooled LRFS was 69.8% (95%CI: 46.1−86.1%). Results are in favor of POCRT in terms of OS but not significant for DFS and LRFS, probably due to the heterogeneity of the included studies and a combination of different prognostic factors.

Comparison of Different Staging Systems Applied to a Cohort of Patients With Oral Tongue and Floor of the Mouth Cancer

Purpose: The present work compares the effects produced by the application of the 7th edition of the tumor node metastasis (TNM) staging system (TNM7), 8th Edition (TNM8) with its two subsequent revisions, and pN-N+ classification on a cohort of patients with oral tongue and floor of the mouth cancer. Methods: A monocentric cohort of 148 patients was retrospectively analyzed. Patients were staged according to the TNM7, TNM8 and revisions, and pN-N+ classification. Stage migration was assessed and overall survival (OS) analyzed with the Kaplan-Meier method. The pT, pN, and stage stratification was evaluated with univariate and multivariate Cox regression and comparing adjacent categories with the log-rank method. Results: pT3-T4a categories showed significant differences in comparison to pT1-T2 for each staging metric employed in both uni- and multivariate analysis. When comparing adjacent pT categories, OS was significantly different only between pT2 and pT3 categories of the TNM8. Disproportionate patient distribution among pN categories was observed in the TNM8, and stratification was scarce. Conversely, in the pN-N+ classification the difference between pN2 and pN3a categories was significant. Only stage IVa reached statistical significance in TNM7, whereas stage III and above were significant in TNM8 and revisions in both uni- and multivariate analysis. However, no significant difference was noted comparing adjacent stages. Conclusion: The TNM8 pT classification differentiated low- from high-risk diseases. Nonetheless, it failed to separate pT1 from pT2 and pT3 from pT4a categories. Conversely, although TNM8 nodal staging was inaccurate, the number of metastatic lymph nodes was more valuable.

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.

The Impact of Histopathological Features on the Prognosis of Oral Squamous Cell Carcinoma: A Comprehensive Review and Meta-Analysis

OBJECTIVE

Over many decades, studies on histopathological features have not only presented high-level evidence of contribution for treatment directions and prognosis of oral squamous cell carcinoma (OSCC) but also provided inconsistencies, making clinical application difficult. The 8th TNM staging system of OSCC has acknowledged the importance of some histopathological features, by incorporating depth of invasion (DOI) to T category and extranodal extension (ENE) to N category. The aim of this systematic review with meta-analysis is to determine the most clinically relevant histopathological features for risk assessment and treatment planning of OSCC and to elucidate gaps in the literature.

METHODS

A systematic review was conducted using PRISMA guidelines, and the eligibility criteria were based on population, exposure, comparison, outcome, and study type (PECOS). PubMed, Cochrane, Scopus, and Web of Science were searched for articles exploring the impact of histopathological features on OSCC outcomes with Cox multivariate analysis. Pooled data were subjected to an inverse variance method with random effects or fixed effect model, and the risk of bias was evaluated using quality in prognosis studies (QUIPS). Quality of evidence was assessed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

The study included 172 articles published from 1999 to 2021. Meta-analyses confirmed the prognostic potential of DOI, ENE, perineural invasion, lymphovascular invasion, and involvement of the surgical margins and brought promising results for the association of bone invasion, tumor thickness, and pattern of invasion with increased risk for poor survival. Although with a small number of studies, the results also revealed a clinical significance of tumor budding and tumor-stroma ratio on predicted survival of patients with OSCC. Most of the studies were considered with low or moderate risk of bias, and the certainty in evidence varied from very low to high.

CONCLUSION

Our results confirm the potential prognostic usefulness of many histopathological features and highlight the promising results of others; however, further studies are advised to apply consistent designs, filling in the literature gaps to the pertinence of histopathological markers for OSCC prognosis.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), identifier CRD42020219630.

Patterns of Regional Recurrence and Salvage Treatment in Patients With Oral Cancer

OBJECTIVES

Regional failure after primary treatment for oral squamous cell carcinoma (OSCC) carries a dismal outcome. Our goal was to investigate the recurrence patterns and salvage treatment in patients with OSCC and regional failure.

STUDY DESIGN

Retrospective chart review of all patients treated for OSCC in a university-affiliated tertiary care center during 2000-2018.

METHODS

Data collected from patients' medical charts included demographics, clinical and pathological features, staging, treatment modalities and outcomes. Patients with insufficient data or a follow-up of less than 2 years were excluded.

RESULTS

Out of 266 surgically treated patients, 55 developed regional recurrence and were included in the study cohort. Forty patients received surgical salvage treatment followed by adjuvant chemo-radiotherapy (CRT). Disease specific survival and overall survival were significantly higher in surgically treated patients compared to patients who received non-surgical treatment (46.7% vs. 0%, log-rank P value < .001 and 35.3% vs. 0%, log-rank P value = .001, respectively) and in patients who recurred regionally more than 10 months following initial treatment (40.8% vs 10.7%, log-rank P value = .065). Patients with early recurrence were older (73.6 vs. 61.3 years) and had a deeper invasion of the primary tumor (10.1 vs. 7 mm).

CONCLUSIONS

Salvage neck dissection is feasible in most cases, providing the best outcomes in patients with OSCC who fail regionally. Close follow-up during the first year after initial treatment is paramount as early recurrence carries a dismal prognosis. Specifically, elderly patients and patients with deeper primary tumor invasion should be closely monitored during the first post-operative year.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Is the Depth of Invasion a Marker for Elective Neck Dissection in Early Oral Squamous Cell Carcinoma?

Objective

The depth of invasion (DOI) is considered an independent risk factor for occult lymph node metastasis in oral cavity squamous cell carcinoma (OCSCC). It is used to decide whether an elective neck dissection (END) is indicated in the case of a clinically negative neck for early stage carcinoma (pT1/pT2). However, there is no consensus on the cut-off value of the DOI for performing an END. The aim of this study was to determine a cut-off value for clinical decision making on END, by assessing the association of the DOI and the risk of occult lymph node metastasis in early OCSCC.

Methods

A retrospective cohort study was conducted at the Erasmus MC, University Medical Centre Rotterdam, The Netherlands. Patients surgically treated for pT1/pT2 OCSCC between 2006 and 2012 were included. For all cases, the DOI was measured according to the 8^th edition of the American Joint Committee on Cancer guideline. Patient characteristics, tumor characteristics (pTN, differentiation grade, perineural invasion, and lymphovascular invasion), treatment modality (END or watchful waiting), and 5-year follow-up (local recurrence, regional recurrence, and distant metastasis) were obtained from patient files.

Results

A total of 222 patients were included, 117 pT1 and 105 pT2. Occult lymph node metastasis was found in 39 of the 166 patients who received END. Univariate logistic regression analysis showed DOI to be a significant predictor for occult lymph node metastasis (odds ratio (OR) = 1.3 per mm DOI; 95% CI: 1.1-1.5, p = 0.001). At a DOI of 4.3 mm the risk of occult lymph node metastasis was >20% (all subsites combined).

Conclusion

The DOI is a significant predictor for occult lymph node metastasis in early stage oral carcinoma. A NPV of 81% was found at a DOI cut-off value of 4 mm. Therefore, an END should be performed if the DOI is >4 mm.

Failure rate in the untreated contralateral node negative neck of small lateralized oral cavity cancers: A multi-institutional collaborative study

OBJECTIVES

The importance of treating the bilateral neck in lateralized small oral cavity squamous cell carcinoma (OCC) is unclear. We sought to define the incidence and predictors of contralateral neck failure (CLF) in patients who underwent unilateral treatment.

MATERIALS AND METHODS

We performed a multi-institutional retrospective study of patients with pathologic T1-T2 (AJCC 7th edition) OCC with clinically node negative contralateral neck who underwent unilateral treatment with primary surgical resection ± adjuvant radiotherapy between 2005 and 2015. Incidence of CLF was estimated using the cumulative incidence method. Clinicopathological factors were analyzed by univariate (UVA) and multivariate analysis (MVA) for possible association with CLF. Kaplan-Meier analysis was used to estimate overall survival (OS).

RESULTS

176 patients were evaluated with a median of 65.9 months of follow-up. Predominant pathologic T-stage was T1 (68%), 8.5% of patients were N1, 2.8% were N2b. Adjuvant radiotherapy was delivered to 17% of patients. 5-year incidence of CLF was 4.3% (95% CI 1.2-7.4%). Depth of invasion (DOI) > 10 mm and positive ipsilateral neck node were significant predictors for CLF on UVA. DOI > 10 mm remained significant on MVA (HR = 6.7, 95% CI 1.4-32.3, p = 0.02). The 2- and 5-year OS was 90.6% (95% CI 86.2-95.0%) and 80.6% (95% CI 74.5-86.8%), respectively.

CONCLUSION

Observation of the clinically node negative contralateral neck in small lateralized OCC can be a suitable management approach in well selected patients, however caution should be applied when DOI upstages small but deeply invasive tumors to T3 on 8th edition AJCC staging.

Biopsy pattern of invasion type to determine the surgical approach in early-stage oral squamous cell carcinoma

Depth of invasion (DOI) and pattern of invasion (POI) indicate tumor invasiveness of oral squamous cell carcinoma (OSCC). However, preoperative DOI evaluation is challenging, and the correlations between DOI and POI are unknown. We aimed to assess DOI and worst pattern of invasion (WPOI) in early-stage OSCC, and evaluate the preoperative predictive ability of biopsy pattern of invasion (BPOI) for WPOI and DOI. This retrospective study included n = 444 OSCC patients with pT1-2N0M0. The prognostic value of DOI, WPOI, and BPOI and the predictive prognostic option for WPOI and DOI by BPOI were assessed. WPOI (1-3 vs 4-5), but not BPOI, predicted the lowest survival rate and highest DOI. To evaluate the difference between WPOI and BPOI, we conducted a POI type-matching analysis of patients with BPOI1-4 and WPOI1-5. Based on each WPOI type, the false-prediction rates (FPR) of BPOI types 1 (n = 23), 2 (n = 89), 3 (n = 252), and 4 (n = 80) were 52.17%, 52.81%, 36.90%, and 0%, respectively. BPOI4 perfectly predict WPOI 4-5. As the false-predicted BPOI 1-2 was almost WPOI2-3 (79.7%), regardless of the existed FPR, patients with BPOI1-2 have longer survival and lower DOI than those with BPOI 4. However, this phenomenon was not observed in BPOI3, because all false-predicted BPOI3 were WPOI4-5 with a high DOI. We provide an alternative predictive prognostic option for WPOI and DOI by evaluating BPOI during OSCC surgical planning, with the recommendation of conservative treatment in patients with BPOI 1-2.

The budding and depth of invasion model in oral cancer: A systematic review and meta-analysis

BACKGROUND

Tumour budding (B) and depth of invasion (D) have both been reported as promising prognostic markers in oral squamous cell carcinoma (OSCC). This meta-analysis assessed the prognostic value of the tumour budding and depth of invasion combination (BD model) in OSCC.

METHODS

Databases including Ovid MEDLINE, PubMed, Scopus and Web of Science were searched for articles that studied the BD model as a prognosticator in OSCC. PICO search strategy was "In OSCC patients, does BD model have a prognostic power?" We used the reporting recommendations for tumour marker prognostic studies (REMARK) criteria to evaluate the quality of studies eligible for systematic review and meta-analysis.

RESULTS

Nine studies were relevant as they analysed the BD model for prognostication of OSCC. These studies used either haematoxylin and eosin (HE) or pan-cytokeratin (PCK)-stained resected sections of OSCC. Our meta-analysis showed a significant association of BD model with OSCC disease-free survival (hazard ratio = 2.02; 95% confidence interval = 1.44-2.85).

CONCLUSIONS

The BD model is a simple and reliable prognostic indicator for OSCC. Evaluation of the BD model from HE- or PCK-stained sections could facilitate individualized treatment planning for OSCC patients.

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

OBJECTIVES

Depth of invasion (DOI) is the most important predictor for lymph node metastasis (LNM) in early stage (T1-T2) oral cancer. The aim of this study is to validate the cut-off value of 4 mm on which the decision to perform an Elective Neck Dissection (END) is made.

MATERIALS AND METHODS

We performed a retrospective study in patients with pathologically proven early stage oral cavity squamous cell carcinoma (OCSCC) without clinical or radiological signs of LNM, who were treated between 2013 and 2018. An END was performed when DOI was ≥ 4 mm and a watchful waiting protocol was applied in patients with DOI < 4 mm.

RESULTS

Three hundred patients were included. END was performed in 77% of patients with DOI ≥ 4 mm, of which 36% had occult LNM (pN+). Patients in the watchful waiting group (48%) developed a regional recurrence in 5.2% for DOI < 4 mm and 24.1% for DOI ≥ 4 mm. For DOI ≥ 4 mm, regional recurrence free survival was higher for patients who were treated with END compared to watchful waiting (p = 0.002). A Receiver-Operator-Curve -analysis showed that a DOI cut-off value of 4.0 mm was the optimal threshold for the prediction of occult LNM (95.1% sensitivity, 52.9% specificity).

CONCLUSION

A DOI of ≥ 4 mm is an accurate cut-off value for performing an END in early stage OCSCC. END results in higher survival rates and lower regional recurrence rates in patients with DOI ≥ 4 mm.

Elective Neck Dissection in T1N0M0 Oral Squamous Cell Carcinoma: When Is It Necessary?

PURPOSE

Elective neck dissection (END) versus observation remains controversial for cT1N0M0 oral cavity squamous cell carcinoma (OSCC). The aim of this study was to determine whether neck dissection is indicated for cT1N0M0 OSCC versus observation when considering oral cavity subsites and depth of invasion (DOI) as predictors.

PATIENTS AND METHODS

A multicenter, ambispective cohort study of patients with cT1N0M0 OSCC treated at the University of Michigan and Beijing Stomatological Hospital from August 1998 to July 2017 with a follow-up end date of July 2019 was performed. Patients were excluded if follow-up was less than 2 years and no neck disease had occurred or if the final pathologic analysis resulted in upstaging to T2 using American Joint Committee on Cancer criteria, eighth edition. A total of 283 patients met the criteria. The main outcome parameter was the 2-year neck metastatic rate.

RESULTS

The total 2-year lymph node metastatic rate was 11.3%. Overall neck metastatic rates escalated consistently according to DOI: less than 2 mm, 2.1%; 2 to 3 mm, 9.4%; 3 to 4 mm, 15.2%; and 4 to 5 mm, 24.6%. On univariate Cox regression analysis, DOI greater than 3 mm, tumor grade, and perineural invasion were statistically significant indicators of 2-year neck metastasis. On multivariate analysis, only DOI and tumor grade remained. On multivariate analysis of 2-year survival, no factors were independent predictors. Our proposed treatment strategy for END based both on statistically significant results for DOI and on review of the raw data using a 20% cutoff analysis showed cutoffs of 2 mm for the tongue (18.2%), 3 mm for the floor of the mouth (40.0%) and upper gingiva (20%), and 4 mm for the lower gingiva (33.3%) and no cutoff for the hard palate (0.0%).

CONCLUSIONS

The watch-and-wait approach remains a reasonable approach in selected patients with cT1N0M0 OSCC. Decision making for END in T1N0M0 patients should minimally consider tumor grade, DOI, and oral cavity subsite.

Survival outcomes after surgical treatment of oral squamous cell carcinoma

OBJECTIVE

To identify the clinicopathological parameters that influence survival in patients with oral squamous cell carcinoma, in order to allow for the development of individualized surveillance programmes and reduce the delay in diagnosis of recurrence.

MATERIALS AND METHODS

Retrospective chart review of 553 patients with a treatment-naïve primary oral squamous cell carcinoma, who underwent primarily curative intended surgery. Exclusion criteria were neoadjuvant radio(chemo)therapy, follow-up < 1 year, perioperative death, inoperable disease, synchronous multiple malignancies and inadequate information on clinicopathological parameters.

RESULTS

The clinicopathological factors that influence overall survival, disease-free survival and locoregional control were calculated. In the multivariate survival analysis, the occurrence of recurrence, presence of extracapsular spread, T- and N-classification were shown to be independent risk factors for overall survival.

CONCLUSION

The identification of these risk factors can lead to the development of individualized follow-up programmes based on risk stratification. This allows for the earliest possible diagnosis of relapse which is essential to offer the patient a realistic second treatment chance and to improve survival rates.

Effectiveness of sentinel lymph node scintigraphy and intraoperative gamma probing with gold standard elective neck dissection in patients with N0 oral squamous cell cancers

OBJECTIVE

Oral cancer ranks in the top three of all cancers in India, accounting for over 30% of all cancers reported. Elective neck dissection (END) is the mainstay of treatment in early disease. Performing ENDs for node negative (N0) patients can result in significant morbidity with questionable benefit and impair the patients' quality of life. Sentinel Lymph Node Biopsy (SLNB), is an emerging investigation helping in risk stratification of patients with early oral cancer and node negative disease. SLNB is a simple, easy to perform investigation with a high sensitivity and plays a major role in avoiding neck dissection. Studies have compared SLNB-based neck dissection with END in early oral cancers, and also on survival benefit with prophylactic neck dissection at the time of primary surgery as compared to watchful waiting followed by therapeutic neck dissection for nodal relapse, in patients with clinical N0 (cN0) oral squamous cell carcinoma (OSCC) on literature search.

AIM

Our primary aim was to determine the effectiveness of lymphoscintigraphy in OSCC in clinically neck node negative (cN0) patients in comparison to gold standard END for nodal metastases identification and secondly to assess the utility of gamma probe in guiding SLNB in this group of patients.

MATERIALS AND METHODS

Fifty-eight patients (M:F = 42:16) with histologically confirmed OSCC of T1-3 stage with cN0 and planned for curative intent primary surgical treatment were divided into two arms. All patients underwent sentinel lymph node (SLN) imaging and biopsy. Arm 1 underwent nodal dissection based on SLNB positivity, while all patients in arm 2 had wide neck dissection irrespective of SLNB findings.

RESULTS

SLN was detected in all 58 patients, 96.4% patients showed SLN immediately postinjection. More than one SLN was found in 94.3% patients and 6.8% patients showed contralateral SLN also. Higher proportion of nodal metastasis were observed in tongue cancers than in remaining floor of mouth and buccal mucosa cancers (38% vs 12%, P< 0.01). We also found significant association between T size and nodal metastasis in our series. Sensitivity of SLNB was 88.23% with a specificity of 100%, both for SLN imaging and gamma probing localization reflecting the reliability of this technique. Serial step sectioning at 150 micrometre is recommended. SLNB showed positive nodes in 29.3 % patients with cN0 neck. We found that the association between the outcome in both arms was not statistically significant. On follow-up, three patients with T3N0 OSCC of arm 2 had nodal recurrence/lung metastases. One patient of arm 1 had nodal recurrence. Two patients expired within one year. As high as 73% patients (22 negative necks out of 30) had unwarranted neck dissection in arm 2.

CONCLUSION

SLNB is an effective method to circumvent unwarranted neck dissection in early OSCC and prevent complications. Gamma probing is a robust and easy tool to identify SLN in T1-3 stages with N0 necks clinically. A positive SLNB is found to be reliable in guiding neck dissection in this small study. Larger studies are warranted to establish its recommendation in routine clinical practice.

Elective Neck Dissection, but Not Adjuvant Radiation Therapy, Improves Survival in Stage I and II Oral Tongue Cancer with Depth of Invasion >4 mm

Purpose/objective(s)

In early-stage, node negative oral tongue cancer, there is limited data supporting tumor depth of invasion (DOI) as an indication for post-operative radiotherapy (PORT) to the primary site. The primary aim of this study is to examine the effect of tumor DOI and PORT on overall survival (OS).

Materials and methods

The National Cancer Database (NCDB) was used to query patients with AJCC stage I and II oral tongue cancer (2006-2013). Patients were stratified by receipt of PORT, elective neck dissection (ND), and DOI (≤4 mm or >4 mm). Kaplan-Meier analysis was performed to compare OS (using the log-rank test) between PORT versus no-PORT. Multivariable Cox proportional hazards regression model performed to evaluate the independent effect of PORT and neck dissection on OS.

Results

Among 939 patients, 69.3% were clinical stage I, 67.4% received ND, 23.4% had DOI >4 mm, and 10.4% received PORT. The addition of PORT did not improve OS with tumor DOI ≤4 mm (p = 0.634) or >4 mm (p = 0.816). The addition of elective neck dissection improved OS for DOI >4 mm (p = 0.010), but not for ≤4 mm (p = 0.128). On multivariable analysis, ND improved OS if DOI >4 mm (HR, 0.37; 95% CI, 0.17-0.81 [p = .012]), when also controlling for age, sex, PORT status, clinical stage, and pathological stage.

Conclusion

Tumor DOI should not be used as a sole indication for PORT in early stage oral tongue cancers. Elective neck dissection at the time of excision of the primary tumor results in higher OS for tumors with DOI >4 mm.

Time to recurrence and patient survival in recurrent oral squamous cell carcinoma

OBJECTIVES

Tumour relapse remains one of the major problems in managing oral squamous cell carcinoma (OSCC) with mortality rates of up to 92%. Early recurrences have a worse prognosis than late relapses. However, few has been written about the influence of clinicopathological parameters on the timing of recurrence and the patient survival.

MATERIALS AND METHODS

Retrospective chart review of 159 patients with an OSCC recurrent disease. Exclusion criteria were neoadjuvant chemoradiotherapy, follow-up <6 weeks, perioperative death, second primaries and inadequate information on clinicopathological parameters. Statistical analysis was performed using univariate and multivariate analysis.

RESULTS

A significant correlation was found in the χ2-analysis between the timing of recurrence and the margin status (p = 0.020), lymph node ratio (p = 0.030) and grading (p = 0.003) of the primary tumour. In the multivariate survival analysis, the timing of recurrence (p < 0.001), margin status of the primary tumour (p = 0.023), presence of extracapsular spread in the primary tumour (p = 0.003) and performance of a salvage treatment (p < 0.001) were shown to be independent risk factors for overall survival.

CONCLUSION

For patients with a recurrent OSCC, the time to recurrence, margin status, extracapsular spread and the performance of a salvage treatment are independent prognostic factors for overall survival. Furthermore, a significant association exists between the moment of recurrence and the lymph node ratio, the margin status and grading of the primary tumour. This knowledge can allow for the development of individualised surveillance programs and like this, an earlier diagnosis and better second treatment chance in the case of a recurrence.