Elective versus therapeutic neck dissection in early carcinoma of the oral tongue

The Depth of Invasion and Level IV Cervical Node Metastasis in Patients with Clinically N0 Tongue Cancer

BACKGROUND

The accurate indication for level IV dissection is crucial for preventing complications such as phrenic nerve damage and chylous fistulas in clinically N0 tongue cancer. Although the depth of invasion is an established independent risk factor for occult lymph node metastasis in tongue cancer, its relationship with level IV metastasis has not been evaluated. This study investigated the relationship between the depth of invasion and level IV nodal metastasis in clinically N0 tongue cancer.

METHODS

We retrospectively investigated clinical N0 patients who underwent glossectomy and level I-IV neck dissection. We examined lymph node metastasis, risk factors, and the relationship between depth of invasion and metastasis.

RESULTS

Our study included 58 patients, and no patient had isolated level IV metastasis. Additionally, there was no level IV metastasis in well-differentiated tumors. Tumor size, depth of invasion, differentiation, and perineural invasion were significantly associated with level IV neck metastasis. We found a critical tumor size of 2.5 cm and depth of invasion of 8 mm for level IV neck metastasis.

CONCLUSION

Based on our findings, we recommend that level IV dissection should be considered for poorly differentiated tumors, tumors greater than 2.5 cm in size, and those deeper than 8 mm. This study highlights the importance of depth of invasion as a prognostic factor for predicting level IV metastasis and suggests that our findings can be used to prevent unnecessary level IV dissections that may lead to complications in tongue cancer surgery.

Depth of invasion as an independent prognostic factor in early-stage oral cavity squamous cell carcinoma

PURPOSE

To determine the significance of depth of invasion as a predictor of recurrence and mortality in tongue and non-tongue early-stage oral cavity squamous cell carcinoma patients treated with surgery and no postoperative radiotherapy.

MATERIALS AND METHODS

344 patients with oral cavity squamous cell carcinoma from 2005 to 2022 at a tertiary academic medical center were reviewed. Patients were included if they had newly diagnosed, previously untreated T1-T2N0 disease treated with surgery alone that was observed within a follow-up of 5 years. For each patient, anatomic site of oral cavity squamous cell carcinoma was categorized as either tongue or non-tongue. Cox proportional hazards regression analyses were performed to determine the association of depth of invasion with recurrence and mortality, with anatomic site, smoking status, and age at biopsy as covariates. Model assumptions were tested by statistical and graphical evaluation using Schoenfeld residuals.

RESULTS

Of 108 patients with T1-T2N0 disease, 78 (72.2 %) had tongue disease, and 30 (27.8 %) had non-tongue disease. Median follow-up was 18.2 months (range, 0.01-58.2 months). In the Cox proportional hazards models, with adjustment for anatomic site and other covariates, depth of invasion positively predicted recurrence (HR 1.16, 95 % CI: 1.01-1.32, p = 0.034) and death (HR 1.42, 95 % CI: 1.11-1.83, p = 0.006).

CONCLUSIONS

Depth of invasion is an independent predictor of recurrence and death across early-stage tongue and non-tongue squamous cell carcinoma. Therefore, depth of invasion may indicate a need for more aggressive treatment than surgery alone, such as postoperative radiotherapy, even in the absence of other adverse features on pathology within the early-stage population.

Prevalence and implications of bilateral and solely contralateral lymph node metastases in oral squamous cell carcinoma

OBJECTIVES

Effective management of neck in oral squamous cell carcinoma (OSCC) is pivotal for oncological outcomes. Although consensus exists for ipsilateral neck dissection (ND), the necessity for contralateral ND remains controversial. This study aimed to assess the prevalence and implications of bilateral/solely contralateral (B/SC) lymph node metastases (LNMs) to determine the need for contralateral elective ND. Additionally, it examined the prevalence and implications of occult B/SC metastases.

MATERIALS AND METHODS

In a retrospective cohort study, 420 OSCC patients underwent primary surgical treatment following German guidelines at a tertiary center. Preoperative contrast-enhanced computed tomography was conducted, and ND adhered to a standardized approach.

RESULTS

Solely contralateral metastases occurred in 0.95% of patients, with bilateral metastases observed in 7.13%. Occult B/SC metastases occurred in 3.81% of the cases. Correlation analysis revealed a statistically significant association between B/SC metastases and higher tumor stages, tumor localization at the upper jaw or floor of the mouth, proximity to the midline, ipsilateral LNMs, and lymphatic invasion (all p < 0.05). Patients with B/SC metastases showed poorer disease-free survival, with statistical significance reached in the bilateral LNMs group (p = 0.010). Similarly, a significant difference was noted in overall survival between patients with bilateral and solely ipsilateral metastases (p = 0.044).

CONCLUSIONS

B/SC LNMs are rare in patients with OSCC, especially in those who present with clinico-radiologically negative ipsilateral necks. Higher rates of B/SC metastases occur in case of advanced tumors and those localized at the upper jaw or floor of the mouth. Ipsilateral LNMs significantly elevate the risk of contralateral LNMs, tripling the associated risk.

CLINICAL RELEVANCE

These findings provide valuable insights for surgeons considering contralateral ND or extended adjuvant treatment for OSCC patients. However, the absence of high-level evidence from randomized controlled trials impedes the establishment of a definitive standard of care.

CT predictors of sub-centimeter occult lymph node metastases in oral cavity squamous cell carcinoma: A case-control study

BACKGROUND

For patients with oral cavity squamous cell carcinoma (OCSCC) without evidence of nodal metastasis (cN0) on pre-operative evaluation, there are no clear guidelines who should undergo elective neck dissection (END) versus clinical surveillance.

OBJECTIVE

To identify CT imaging characteristics of sub-centimeter lymph nodes that would help predict the likelihood of nodal metastases on pathology.

METHODS

Retrospective review of cN0 OCSCC patients at a tertiary academic medical center was performed. Inclusion criteria included elective neck dissection, pre-operative CT imaging and presence of metastatic disease within lymph nodes. Control group consisted of patients without nodal metastases on pathology. CT features that were evaluated included asymmetric size, disrupted fatty hilum, asymmetric number, presence of cortical nodule, cortical nodule size, and round/oval shape. We evaluated the associations between CT LN features and the presence of metastases using multi-level mixed-effects logistic regression models. Model evaluation was performed using 5-fold cross-validation. The positive predictive value (PPV) and negative predictive value (NPV) were calculated.

RESULTS

26 patients in each study and control groups were included. Three-level mixed-effects logistic regression models indicated round/oval shape (OR = 1.39, p = .01), asymmetric number (OR = 7.20, p = .005), and disrupted fatty hilum (OR = 3.31, p = .04) to be independently predictive in a 3-variable model with sensitivity = 38.0%, specificity = 92.0%, and PPV = 93.8%.

CONCLUSIONS

In cN0 OCSCC patients undergoing END, round/oval shape, asymmetric number, and disrupted fatty hilum of lymph nodes on pre-operative CT imaging are novel and highly predictive of occult nodal disease.

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.

Oral Cavity Cancer Surgical and Nodal Management: A Review From the American Head and Neck Society

Importance

Lymph node metastases from oral cavity cancers are seen frequently, and there is still inconsistency, and occasional controversies, regarding the surgical management of the neck in patients with oral cancer. This review is intended to offer a surgically focused discussion of the current recommendations regarding management of the neck, focusing on the indications and extent of dissection required in patients with oral cavity squamous cell carcinoma while balancing surgical risk and oncologic outcome.

Observations

The surgical management of the neck for oral cavity cancer has been robustly studied, as evidenced by substantial existing literature surrounding the topic. Prior published investigations have provided a sound foundation on which data-driven treatment algorithms can generally be recommended.

Conclusions

Existing literature suggests that patients with oral cavity cancer should be fully staged preoperatively, and most patients should receive a neck dissection even when clinically N0. Quality standards supported by the literature include separation of each level during specimen handling and lymph node yield of 18 or more nodes. Sentinel lymph node biopsy can be considered in select tumors and within a well-trained multidisciplinary team.

Do patients with cN0 oral squamous cell carcinoma benefit from elective neck dissection? A large-scale population-based study

BACKGROUND

The neck management of clinical-nodal negative (cN0) oral squamous cell carcinoma (OSCC) remains controversial. Elective neck dissection (END) and observation are the main strategies, but it is still not clear who could benefit the most from END. The purpose of this study was to clarify the potential clinical factors that affect the therapeutic value of END and to explore the actual characteristics associated with benefit from END.

METHODS

Patients with cN0 OSCC were identified in the SEER database from 2000 to 2019. 5-year Overall survival (OS) and disease-specific survival (DSS) were analyzed using the Kaplan‒Meier method, and the hazard ratios (HRs) for survival were estimated using the Cox regression model. Multiple subgroup analyses of DSS and OS among different factors, comparing END and No END, were performed.

RESULTS

A total of 17,019 patients with cN0 OSCC were included. The basic survival analysis and Cox regression model showed that END increased the probability of 5-year DSS and OS and was an independent prognostic factor. However, among patients who underwent only primary tumor surgery, no significant differences were found between the END and No END groups in 5-year DSS (P = 0. 585) and OS (P = 0.465). Further subgroup analysis showed that primary sites and T stage, but not other factors, might influence the benefit of END. Significant differences were found for T1 (P < 0.001 for OS) and T2 (P = 0.001 for DSS and < 0.001 for OS) tongue squamous cell carcinoma (TSCC) but not for other primary tumor sites.

CONCLUSION

This large-scale retrospective population-based cohort study suggests that not all patients with cN0 OSCC could benefit from END. Patients with cN0 TSCC are recommended to undergo END, especially with early-stage tumors.

Regional Nodal Recurence as a Prognostic Factor in Patients Kept on Observation for cT1-T2 Oral Squamous Cell Carcinomas of Tongue: A Meta-Analysis of 11,973 Patients

The surgical management of the clinically node negative neck in T1-T2 early oral tongue squamous cell carcinoma (OTSCC) has been the topic of debate since few decades. As the occult cervical lymph node metastasis is considered to be the primary prognostic factor in early OTSCC, this meta-analysis has been carried out to find the risk of regional nodal recurrence on patients kept under observation than those who have underwent Elective neck dissection (END). The articles were electronically retrieved from Ovid Medline, PubMed, Cochrane and Scholar for comparison of Observation versus END in early OTSCC. The search strategy identified 35 relevant review articles from April 1979 to April 2020 from different search engines. A total of 11,973 patients from 30 retrospective analyses, 4 prospective and 1 randomized control trials were included in this meta-analysis. Overall test revealed (OR: 13.02 95% CI 1.360-17.154) with t test 2.382 and p value 0.023 which is statistically significant and showed that END significantly reduced the risk of regional nodal recurrence. This meta-analysis finds that there is statistically significant relationship when END was performed which reduced the risk of regional nodal recurrence as seen in patients kept on Observation thereby affecting the Overall survival (OS) rate.

Nodal frozen section + elective neck dissection as an alternative to sentinel lymph node biopsy for the management of cT1-2N0 oral squamous cell carcinoma patients: a viability and accuracy study

PURPOSE

Oral Squamous Cell Carcinoma (OSCC) is characterized by a high aggressiveness and a tendency to metastasize. The management of the neck in cT1-2N0 patients c follows three strategies: watchful waiting, elective neck dissection (END) or sentinel lymph node biopsy (SLNB). The aim was to assess the viability of intraoperative frozen sections of the nodes of cT1-2N0 to spot occult metastases as an alternative to SLNB, performing a modified radical neck dissection (MRND) in intraoperatively positive patients.

METHODS

The patients were treated at the Maxillo-Facial Surgery Unit of Policlinico San Marco of Catania between 2020 and 2022. END was performed in all patients, including frozen section examination of at least one clinically suspicious node per level. In case of positivity after frozen section examination, neck dissection was extended to levels IV and V.

RESULTS

All frozen sections were compared with a definitive test after paraffin inclusion. During surgery, 70 END were performed, and 210 nodes were analyzed with frozen sections. Among the 70 END, 52 were negative after frozen Sects. (156 negative nodes), and surgery was ended. Five of the 52 negative ENDs resulted in pN + after paraffin inclusion (9.6%), which underwent postoperative adjuvant treatment. The sensibility of our END + frozen section method was 75%, while the specificity of our test was 94%. The negative predictive value was 90,4%.

CONCLUSIONS

Elective neck dissection + intraoperative frozen section could be an alternative to SLNB to spot occult nodal metastases in cT1-2N0 OSCC due to the opportunity to perform a one-step diagnostic/therapeutic procedure.

Accuracy of Magnetic Resonance Imaging in Detecting Tumor Depth of Invasion in Squamous Cell Carcinoma of the Tongue: A Systematic Review

Objective

The objective of the study was to detect the accuracy of Magnetic Resonance Imaging (MRI) in assessing tumor depth of invasion (DOI) in squamous cell carcinoma (SCC) of the tongue.

Material and Methods

The electronic search of PubMed (including MEDLINE), COCHRANE CENTRAL and Google Scholar search engine for articles published from January 1, 2000, to September 31, 2021, was conducted and also searched the lists of references of relevant articles and reviews for studies involving patients with squamous cell carcinoma of the tongue.

Results

A total of 5362 articles were retrieved in the initial search. After the initial search process, 13 full-text articles were reviewed. Out of these 13 articles, seven met the inclusion criteria and were thus included in this systematic review.

Conclusion

The MRI-determined DOI based on T1-weighted sequences increases with increasing T stage. There is the highest correlation between the MRI-derived DOI and the histopathological DOI with increasing T stage. Therefore, MRI provides satisfactory diagnostic accuracy for measuring tumor DOI and, thus, may be considered a predictor of tumor stage.

Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment

BACKGROUND

Surgery is a common treatment option in oral cavity cancer (and less frequently in oropharyngeal cancer) to remove the primary tumour and sometimes neck lymph nodes. People with early-stage disease may undergo surgery alone or surgery plus radiotherapy, chemotherapy, immunotherapy/biotherapy, or a combination of these. Timing and extent of surgery varies. This is the third update of a review originally published in 2007.

OBJECTIVES

To evaluate the relative benefits and harms of different surgical treatment modalities for oral cavity and oropharyngeal cancers.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 9 February 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared two or more surgical treatment modalities, or surgery versus other treatment modalities, for primary tumours of the oral cavity or oropharynx.

DATA COLLECTION AND ANALYSIS

Our primary outcomes were overall survival, disease-free survival, locoregional recurrence, and recurrence; and our secondary outcomes were adverse effects of treatment, quality of life, direct and indirect costs to patients and health services, and participant satisfaction. We used standard Cochrane methods. We reported survival data as hazard ratios (HRs). For overall survival, we reported the HR of mortality, and for disease-free survival, we reported the combined HR of new disease, progression, and mortality; therefore, HRs below 1 indicated improvement in these outcomes. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We identified four new trials, bringing the total number of included trials to 15 (2820 participants randomised, 2583 participants analysed). For objective outcomes, we assessed four trials at high risk of bias, three at low risk, and eight at unclear risk. The trials evaluated nine comparisons; none compared different surgical approaches for excision of the primary tumour. Five trials evaluated elective neck dissection (ND) versus therapeutic (delayed) ND in people with oral cavity cancer and clinically negative neck nodes. Elective ND compared with therapeutic ND probably improves overall survival (HR 0.64, 95% confidence interval (CI) 0.50 to 0.83; I2 = 0%; 4 trials, 883 participants; moderate certainty) and disease-free survival (HR 0.56, 95% CI 0.45 to 0.70; I2 = 12%; 5 trials, 954 participants; moderate certainty), and probably reduces locoregional recurrence (HR 0.58, 95% CI 0.43 to 0.78; I2 = 0%; 4 trials, 458 participants; moderate certainty) and recurrence (RR 0.58, 95% CI 0.48 to 0.70; I2 = 0%; 3 trials, 633 participants; moderate certainty). Elective ND is probably associated with more adverse events (risk ratio (RR) 1.31, 95% CI 1.11 to 1.54; I2 = 0%; 2 trials, 746 participants; moderate certainty). Two trials evaluated elective radical ND versus elective selective ND in people with oral cavity cancer, but we were unable to pool the data as the trials used different surgical procedures. Neither study found evidence of a difference in overall survival (pooled measure not estimable; very low certainty). We are unsure if there is a difference in effect on disease-free survival (HR 0.57, 95% CI 0.29 to 1.11; 1 trial, 104 participants; very low certainty) or recurrence (RR 1.21, 95% CI 0.63 to 2.33; 1 trial, 143 participants; very low certainty). There may be no difference between the interventions in terms of adverse events (1 trial, 148 participants; low certainty). Two trials evaluated superselective ND versus selective ND, but we were unable to use the data. One trial evaluated supraomohyoid ND versus modified radical ND in 332 participants. We were unable to use any of the primary outcome data. The evidence on adverse events was very uncertain, with more complications, pain, and poorer shoulder function in the modified radical ND group. One trial evaluated sentinel node biopsy versus elective ND in 279 participants. There may be little or no difference between the interventions in overall survival (HR 1.00, 95% CI 0.90 to 1.11; low certainty), disease-free survival (HR 0.98, 95% CI 0.90 to 1.07; low certainty), or locoregional recurrence (HR 1.04, 95% CI 0.91 to 1.19; low certainty). The trial provided no usable data for recurrence, and reported no adverse events (very low certainty). One trial evaluated positron emission tomography-computed tomography (PET-CT) following chemoradiotherapy (with ND only if no or incomplete response) versus planned ND (before or after chemoradiotherapy) in 564 participants. There is probably no difference between the interventions in overall survival (HR 0.92, 95% CI 0.65 to 1.31; moderate certainty) or locoregional recurrence (HR 1.00, 95% CI 0.94 to 1.06; moderate certainty). One trial evaluated surgery plus radiotherapy versus radiotherapy alone and provided very low-certainty evidence of better overall survival in the surgery plus radiotherapy group (HR 0.24, 95% CI 0.10 to 0.59; 35 participants). The data were unreliable because the trial stopped early and had multiple protocol violations. In terms of adverse events, subcutaneous fibrosis was more frequent in the surgery plus radiotherapy group, but there were no differences in other adverse events (very low certainty). One trial evaluated surgery versus radiotherapy alone for oropharyngeal cancer in 68 participants. There may be little or no difference between the interventions for overall survival (HR 0.83, 95% CI 0.09 to 7.46; low certainty) or disease-free survival (HR 1.07, 95% CI 0.27 to 4.22; low certainty). For adverse events, there were too many outcomes to draw reliable conclusions. One trial evaluated surgery plus adjuvant radiotherapy versus chemotherapy. We were unable to use the data for any of the outcomes reported (very low certainty).

AUTHORS' CONCLUSIONS

We found moderate-certainty evidence based on five trials that elective neck dissection of clinically negative neck nodes at the time of removal of the primary oral cavity tumour is superior to therapeutic neck dissection, with increased survival and disease-free survival, and reduced locoregional recurrence. There was moderate-certainty evidence from one trial of no difference between positron emission tomography (PET-CT) following chemoradiotherapy versus planned neck dissection in terms of overall survival or locoregional recurrence. The evidence for each of the other seven comparisons came from only one or two studies and was assessed as low or very low-certainty.

Worst Pattern of Invasion as an Independent Predictor of Lymph node Metastasis and Prognosis in oral Cavity Squamous cell carcinoma - A Retrospective Cohort Study

Although Worst pattern of invasion (WPOI) is one of the histopathological (HP) markers that has been utilized in risk stratification of oral squamous cell carcinoma (OSCC) patients, its potential as an independent predictive factor for lymph node metastasis (LNM) and prognosis is least analyzed. Aim of the study is to analyze the relationship of various HP parameters to WPOI, their propensity for lymph node metastasis and prognostic value. This retrospective study included 140 patients diagnosed with resectable OSCC who underwent definitive surgery. Multiparametric HP risk assessment was done on the postoperative specimen and patients were categorized as low-risk WPOI (Type 1-3), and high-risk group (type 4 and 5). After categorization, 36.1% patients had low-risk WPOI and 63.9% had high-risk WPOI. Significant association was noted between WPOI and patient's age (p = 0.001), nodal stage (p = 0.001), lymphovascular invasion (LVI) (p = 0.006) and neural invasion (p = 0.001). 87% patients with nodal metastasis had high risk WPOI. LVI (p = 0.014) and WPOI (p < 0.001) had significant predictive role in LNM. High-risk WPOI and bone involvement were found to be predictive factors for overall survival, and only high risk WPOI had strong correlation with disease free survival having significant poor prognosis. Analyzing WPOI is essential in reporting HP specimens in OSCC. High-risk WPOI can act as an independent predictor for LNM, early recurrence and poor prognosis. Incorporation of WPOI into TNM staging is recommended to improve clinician's ability to prognosticate and individualize treatment strategies.

Prediction Formula for Pathological Depth of Invasion From Clinical Depth of Invasion in Tongue Squamous Cell Carcinoma (SCC) Stage I/II Cases

BACKGROUND

 The depth of invasion (DOI) of tongue squamous cell carcinoma (SCC) is an important prognostic factor. The definition is clear for pathological DOI (pDOI), but the treatment strategy is determined by the preoperative clinical DOI (cDOI). Few studies have investigated the difference between these DOIs. The purpose of this study was to obtain the correlation equation between cDOI and pDOI for Stage I/II tongue SCC and to consider the points to be noted in actual clinical practice.

METHODS

 In this retrospective study, 58 patients with clinical stage I/II tongue SCC were included. Correlations between cDOI and pDOI were obtained for all 58 cases, as well as for 39 cases which excluded superficial and exophytic lesions.

RESULTS

 The overall cDOI and pDOI median values were 8.0 and 5.5 mm, respectively; the 2.5 mm reduction was significant (p < 0.01). The correlation equation was pDOI = 0.81 × cDOI-0.23 (r = 0.73). Furthermore, re-analysis of the 39 cases revealed that pDOI = 0.84 × cDOI-0.37 (r = 0.62). Hence, a derived equation pDOI = 0.84 × (cDOI-0.44) was obtained to predict pDOI from cDOI.

CONCLUSIONS

 This study indicated that it is necessary to consider contraction due to specimen fixation by subtracting the thickness of the mucosal epithelium. Clinical T1 cases with a cDOI of 5 mm or less had a pDOI of 4 mm or less, and it would be expected to have low positive rate of neck lymph node metastasis.

Oncological outcome of contralateral submental artery island flap versus primary closure in tongue squamous cell carcinoma: randomized non-inferiority clinical trial

The aim of this study was to test the non-inferiority of the contralateral submental island flap (CSIF) compared with primary closure (PC) regarding local recurrence after partial glossectomy in patients with oral tongue squamous cell carcinoma (OTSCC). This open-label, non-inferiority randomized controlled trial enrolled patients with cT1-2 lateralized OTSCC. The primary outcome was local recurrence by 12 months postoperative. Non-inferiority would be declared if the upper limit of the two-sided 95% confidence interval (CI) for the proportion difference in local recurrence between the two groups did not exceed a non-inferiority margin of 15.0%. The functional outcome was assessed for superiority through secondary outcomes. In the intention-to-treat analysis, the local recurrence rate was 3.1% (1/32) in the CSIF group versus 9.4% (3/32) in the PC group; the proportion difference was - 6.3% (95% CI -18.0% to 5.5%). In the per-protocol analysis, the local recurrence rate was 3.1% (1/32) versus 3.3% (1/30); the proportion difference was - 0.2% (95% CI -9% to 8.6%). Speech was significantly superior in the CSIF group (P = 0.001). In conclusion, the CSIF was found to be non-inferior to PC regarding local recurrence at 1 year. A limitation of this study is the relatively large non-inferiority margin and consequently relatively small sample size. Further studies with a smaller non-inferiority margin and therefore larger sample size are needed to validate these findings.

Need for adjuvant radiotherapy in oral cancer: depth of invasion rather than tumor diameter

PURPOSE

The 8th edition of the TNM Cancer Staging Manual incorporates depth of invasion (DOI) into the pathologic tumor classification for oral squamous cell carcinoma (OSSC). While deep invading tumors with small tumor diameters (TD) have been categorized as early stage tumors in the 7th edition, they are now upstaged, potentially influencing the decision to initiate adjuvant radiotherapy (RT).

METHODS

OSCC patients surgically treated with curative intent between 2010 and 2019 were consecutively included. Tumors were staged based on TD only (according to the 7th edition TNM Cancer Staging Manual), then restaged based solely on DOI.

RESULTS

Of the 133 included patients, 58 patients (43.6%) had a different pT-stage when using DOI instead of TD for staging (upstaging in 23.3%). Overall survival (OS) was significantly worse in patients who were upstaged with DOI. In addition, stratification by adjuvant RT showed significant worse OS in upstaged patients without receiving adjuvant RT.

CONCLUSIONS

DOI seems to be an import indicator for adjuvant RT in OSCC-patients.

Elective Neck Dissection Versus Observation in cT1-T2 Oral Tongue Squamous Cell Carcinoma: A Meta-Analysis of 11,973 Patients

The surgical management of the clinical negative neck node in early oral tongue squamous cell carcinoma (OTSCC) has been the topic of debate since few decades. As the occult cervical lymph node metastasis is considered to be the prime prognostic factor in early OTSCC, this meta-analysis has been carried out to find the risk of regional nodal recurrence, disease specific survival and overall survival rates in outcome of Elective neck dissection (END) versus patients under observation. The articles were electronically retrieved from Ovid Medline, PubMed, Cochrane and Scholar for comparison of END versus Observation in early OTSCC. The search strategy identified 37 relevant review articles from April 1979 to April 2020 from different search engines. A total of 11,973 patients from 32 retrospective analysis, 4 prospective and 1 randomised control trial were included in this meta-analysis. Statistical analysis revealed Overall test (OR: 5.31 95% CI: - 2.132-14.698) with t-test 1.919 and p value 0.113 which is not statistically significant but the readings says that there is always better Disease specific survival with END patients rather than patients kept on observation. Overall test revealed (OR: 13.02 95% CI: 1.360-17.154) with t test 2.382 and p value 0.023 which is statistically significant and showed that End significantly reduced the risk of regional nodal recurrence. Overall test revealed (OR: 7.93 95% CI: - 15.461-4.238) with t test - 1.347 and p value 0.220 which is statistically insignificant and but showed that to some extent Overall survival improves in patient with END than the patients kept on observation. This meta-analysis find that there is statistically significant relationship when Elective neck dissection was performed which reduced the risk of regional nodal recurrence. This analysis didn't statistically find any significance in Disease specific survival and Overall survival with Elective neck dissection patients rather than patients kept on observation but however showed good prognosis when elective neck dissection was performed.

Evaluation of Tumour Volume as a Prognostic Factor in Carcinoma Buccal Mucosa

(1) To determine tumor volume by clinical measurement, imaging and histopathological examination in patients with squamous carcinoma of buccal mucosa. (2) To correlate tumor volume with lymph-node metastasis and loco-regional control. Retrospective Observational Study. Rural tertiary care hospital. 75 Patients undergoing surgery for T2 (68%) and T3 (32%) Oral squamous carcinomas were included in this observational study. Tumor volume-a product of maximum length, breadth and thickness, was determined clinically and by imaging. Tumor volume on histopathology was documented and correlated with lymph-node metastasis. After 13 months minimum follow-up, tumor volume was correlated with loco-regional control. Recurrences were analysed with regard to tumor volume, depth of invasion, lymph-node metastasis and resection margins. Average tumor volume was 7.1 cm3among T2 and 14.4 cm3among T3. 25% of T2 tumors had metastatic lymph-nodes compared to 33.3% in T3. There was positive correlation between tumor volume and lymph-node metastasis. Lymph-node metastasis was absent when tumor volume was < 8 cm3. There were 4 local and 2 regional recurrences in this study. Average histopathological tumor volume among patients who had local recurrence was 12.95 cm3. Regional recurrences occurred in tumors staged N2b and N3b on histopathology. Average depth of invasion in patients with recurrence was 10.33 mm.. Tumor volume represents actual tumor load and correlates with lymph node metastasis and prognosis in oral cancers. Depth of invasion and tumor thickness influence staging and prognosis. Large volume tumors have poor oncological outcome.

Treatment and Prognosis of Oral Cancer Patients with Confirmed Contralateral Neck Metastasis: A Multicenter Retrospective Analysis

The prognosis of oral cancer that has metastasized to the contralateral cervical lymph nodes is poor, although the appropriate treatment method has not been established because of its rarity. A multicenter retrospective study on the treatment and prognosis of pN2c oral cancer patients was conducted. We investigated the treatment and prognosis of 62 pN2c patients out of 388 pN+ patients with oral squamous cell carcinomas. Statistical analysis was performed on the various factors with overall survival (OS) and disease specific survival (DSS). In multivariate cox regression analysis, advanced T stage was significantly correlated with poor OS (p = 0.011) and DSS (p = 0.023) of patients with pN2c neck. In pN2c patients, OS, DSS, and neck control was not different between those undergoing ipsilateral neck dissection initially and those undergoing bilateral neck dissection. Thus, contralateral elective neck dissection is not recommended. The most important risk factor for prognosis in pN2c oral cancer patients is advanced T stage. No evidence was found to recommend contralateral elective neck dissection in clinically N1/2b patients. Therefore, the indication for contralateral elective neck dissection in N1/2b patients should be carefully determined in consideration of individual conditions.

Critical Review of the Current Evidence on Sentinel Node Biopsy in Oral Cancer

PURPOSE OF REVIEW

With contemporary surgery of the cN0 neck in early oral cancer becoming more selective, sentinel node biopsy (SNB) is gaining popularity as a possible alternate option to elective neck dissection (END). This review attempts to critically appraise the current evidence and highlight pertinent arguments for the use of SNB in early oral cancers.

RECENT FINDINGS

Based on the recent randomized trials, it is imperative to perform an END at the time of primary resection in cN0 oral cancers. The much criticized false negative rate of SNB can be argued to be equal to the regional failure rate after END for pN0 necks, possibly making a case for SNB due to the reduction in number of neck dissections. There still lies ambiguity on the technique, protocols, and benefit of SNB over END. The role of extended histopathological techniques and the implications of micrometastasis and isolated tumor cells for treatment intensification remain questionable. Currently, SNB is an intermediary between routine imaging and END that needs to evolve before it can become a practice changing alternative to END itself. More efforts are needed in standardizing the protocols for SNB.

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.

Role of Adjuvant Radiotherapy in Early Stage Tongue Cancer: Need for Establishing Stringent Guidelines

The primary objective of this study was to determine, using population-based data, whether the addition of postoperative radiotherapy (RT) provides an overall survival benefit in patients with early primary squamous cell carcinoma (SCC) of tongue. The study included the data of tongue cancer patients treated between January 2016 and July 2019 retrieved from our hospital database. Tumours limited to pathologic T1 and T2 category managed with primary surgery with or without postoperative external beam RT were included. Overall survival (OS) and disease-free survival (DFS) were the main outcomes of interest. A total of 211 cases of oral cancer were evaluated and all the patients had clear surgical and pathological margins. Postoperative adjuvant therapy (PORT) was received by 16 patients. Comparison of DFS and OS at 2-year follow-up depicted a similar outcome (p = 0.582 and p = 0.312 respectively). Findings from our study suggest that in the absence of any absolute advantage on quantifiable survival and disease control, it is necessary to define stringent criteria when advocating PORT in early tongue cancer.

Oral cancer: changing the aim of the biopsy in the age of precision medicine. A review

Oral cancer is a heterogeneous disease that develops through a complex, multi-step process. Precision medicine should help to better understand its molecular basis, integrate traditional classifications and have a positive impact on cancer management. To apply this information in clinical practice, we need to define its histology and identify biomarkers expressed by the tumour that provide useful information for planning tailored treatment. The most reliable information currently derives from evaluation of biomarkers on post-operative samples. To plan personalised treatment, oncologists need to assess these markers on biopsy samples. We reviewed the recent literature and identified 6 of 184 publications that compared markers measured on biopsy and post-operative samples or assessed their predictivity for the development of lymph node metastases. Data from these studies suggest that markers measured on biopsy samples can provide useful indications for tailoring treatments. However, due to their heterogeneity and low level of evidence, these results need to be confirmed by clinical studies on a large population to standardise and validate biomarkers in biopsies and to assess their reliability in other diagnostic mini-invasive procedures such as radiomics and liquid biopsy.

TERT Promoter Mutations Are Enriched in Oral Cavity Cancers and Associated With Locoregional Recurrence

Telomerase reverse transcriptase (TERT) promoter mutations are prognostic in many cancers and have been observed in human papillomavirus (HPV)-negative head and neck squamous cell carcinomas (HNSCCs). However, the role of TERT promoter mutations in HPV-negative HNSCCs remains poorly understood in these cancers, which have increased risk for locoregional failure (LRF).

PATIENTS AND METHODS

We retrospectively identified patients who were diagnosed with HNSCC between July 1, 2004, and October 12, 2017, at Memorial Sloan Kettering Cancer Center and whose tumors underwent next-generation sequencing using the MSK-IMPACT panel. Patients with HPV-positive oropharyngeal squamous cell carcinoma (SCC) were excluded. Cumulative incidence of LRF, patterns of failure, and overall survival were measured.

RESULTS

We identified 117 patients with SCC of the oral cavity (OSCC), larynx, hypopharynx, or HPV-negative oropharynx whose tumors underwent next-generation sequencing. Sequencing was performed on 95 tumors that were obtained after recurrence and 22 that were obtained before recurrence. TERT promoter mutations were enriched in OSCC compared with laryngopharyngeal cancers (81.1% v 7.0%; P < .001), which was the largest genetic difference between these anatomic disease subsites. TERT promoter mutations were associated with LRF in OSCCs (Gray's test, P < .001) and in the overall cohort (Gray's test, P < .001). On multivariate analysis, TERT promoter mutations were associated with an increased risk for LRF (subdistribution hazard ratio, 2.82; 95% CI, 1.47 to 5.42; P = .0019), independent of oral cavity primary site and TP53 mutation status.

CONCLUSION

TERT promoter status is associated with the cumulative incidence of LRF and patterns of failure. TERT promoter mutations may define a subset of OSCCs with unique pathogenesis that is associated with an increased risk of LRF. Validation in prospective cohorts is warranted.

Lip and Oral Cavity Squamous Cell Carcinoma

Lip and oral cavity squamous cell carcinoma (SCC) develop from progressive dysplasia of these mucosal structures. The cancers are often preceded by premalignant lesions, and any nonhealing ulcers of the lip or oral cavity should be biopsied. Some risk factors for these 2 subsites overlap and include tobacco use, alcohol use, and an immunocompromised state. Lip and oral cavity SCC are clinically staged based on physical examination and imaging. The 5-year overall survival for early-stage lip and oral cavity SCC is around 70% to 90% but decreases to about 50% for late-stage disease.

Primary Tumour Characteristics Poorly Correlate with Extracapsular Spread and Cervical Sublevel IIb Metastasis in Patients with Oral Squamous Cell Carcinoma and Clinically N0 Neck: A Retrospective Study

Introduction

Nodal metastasis reduces the survival by 50% in head-and-neck squamous cell carcinomas. The presence of nodal extension/extracapsular spread (ECS) further reduces survival. Current literature favors a selective level IIb sparing neck dissection in clinically N0 neck. Studies have evaluated the role of primary tumour size, number of lymph nodes, and depth of invasion (DOI) with the occurrence of extranodal extension (ENE).

Patients and Methods

Patients were retrospectively reviewed who presented with oral cavity carcinomas and clinically N0 neck. Relationship was sought between tumour site, size, histological grading, DOI, and the occurrence of level IIb metastasis and ECS. A P < 0.05 was considered statistically significant.

Results

The relationship showed insignificant correlation with P values (0.6643, 0.6704, 0.6779, and 0.6779) between site, size, grading, DOI, and level IIb and ENE.

Discussion

Previous studies have shown DOI >5 mm and lymph node size 15 mm and multiple lymph nodes predict ECS. DOI and primary site with more than 20% for occult metastasis predicts elective neck treatment. However, in our study, no correlation was found between primary tumour characteristics and ECS or level IIb metastasis. Elective neck dissection is the standard surgical protocol from both diagnostic and therapeutic viewpoints. The only criterion for level IIb dissection is concomitant presence of level IIa involvement intraoperatively. Since ENE can occur early in the disease process, elective neck dissection remains the standard of care.

Elective node dissection versus observation for management of patients with early-stage cT1/T2N0 tongue carcinoma: A systematic review and meta-analysis of prospective studies

OBJECTIVE

To carry out a meta-analysis of prospective literature comparing the clinical efficacy of elective neck dissection (END) vs observation (OBS) in patients with early-stage cT1/T2N0 tongue carcinoma.

DESIGN/SETTING/PARTICIPANTS/OUTCOME MEASURES

We systematically reviewed four databases from inception to 30-October-2020. We considered all studies meeting the following PICOS conditions: (a) Patients: early-stage cT1/T2N0 tongue carcinoma, (b) Intervention: END, (c) Comparator: OBS, (d) Outcomes: local tongue recurrence, cervical nodal recurrence, disease-specific survival (DSS) rate, and disease-free survival (DFS) rate and (e) Study design: prospective reports. We pooled dichotomous data as relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

Four studies (one case-control study and three randomised controlled trials) met our inclusion criteria. There were 448 eligible patients (225 and 223 patients were treated with END and OBS, respectively). END significantly correlated with improved DSS rate (RR = 1.15, 95% CI: 1.04-1.27, P = .007). Nonetheless, there were no significant differences between END and OBS groups regarding the rates of local tongue recurrence (RR = 1.23, 95% CI: 0.50-3.03, P = .65), cervical nodal recurrence (RR = 0.45, 95% CI: 0.16-1.27, P = .13) and DFS rate (RR = 1.08, 95% CI: 0.91-1.27, P = .38). Pooled analysis for cervical nodal recurrence was heterogeneous, and sensitivity analysis revealed a significantly lower cervical nodal recurrence rate in favour of END group (RR = 0.30, 95% CI: 0.13-0.67, P = .004).

CONCLUSION

END correlated with a significant decrease in cervical nodal recurrence and improved DSS rate. END might be superior to OBS in patients with early-stage cT1/T2N0 tongue cancer.

Long non‑coding RNA MIR4713HG aggravates malignant behaviors in oral tongue squamous cell carcinoma via binding with microRNA let‑7c‑5p

Oral tongue squamous cell carcinoma (OTSCC) is one of the most aggressive pathological types of head and neck squamous cell carcinoma, and presents with rapid local invasion and metastasis. The present study confirmed that the long non‑coding (lnc) RNA MIR4713HG was markedly upregulated in both OTSCC tissues and cell lines and associated with poor survival. The present study performed a series of experiments to investigate the impact of MIR4713HG on OTSCC and revealed that upregulation of MIR4713HG had a crucial role in promoting cell proliferation and metastasis of OTSCC cell lines both in vitro and in vivo. By applying bioinformatics analyses, micro RNA let‑7c‑5p was observed to physically bind with MIR4713HG, and the knockdown of let‑7c‑5p could counteract the influence of MIR4713HG on OTSCC. Furthermore, the present study demonstrated that let‑7c‑5p performed its regulating role in OTSCC via affecting the expression level of transmembrane channel like 7 (TMC7). In conclusion, the present study demonstrated that lncRNA MIR4713HG acted as a pro‑tumor factor facilitating cell proliferation and metastasis of OTSCC via affecting the let‑7c‑5p/TMC7 signaling pathway, which presents as a promising therapeutic target in OTSCC.

High-risk early-stage oral tongue squamous cell carcinoma, when free margins are not enough: Critical review

Oral tongue squamous cell carcinoma (OTSCC) is a quite peculiar disease from an anatomical and biological standpoint. An increasing amount of literature highlights the existence of a small subset of T1-T2N0 OTSCC, properly resected on a margin-dependent basis, which conversely proved higher than expected rates of loco-regional/distant failure and disease-specific mortality. These specific high-risk tumors might not have a margin-dependent disease and could possibly benefit from a more aggressive upfront loco-regional treatment, especially addressing the so-called T-N tract. Widespread adoption of a histopathological risk model would allow early recognition of these high-risk diseases and, consequently, intensification of the traditional treatment strategies in that specific niche. We reviewed the available knowledge trying to shed light on the potential determinants of the dismal prognosis of these high-risk OTSCC, with special reference to the role of overlooked T-N tract involvement and possible alternatives in terms of elective neck management and risk stratification.

Research on neck dissection for oral squamous-cell carcinoma: a bibliometric analysis

Neck dissection for oral squamous-cell carcinoma (OSCC) is a clinically controversial issue and has therefore been the subject of abundant research. However, no one has performed a bibliometric study on this topic to date. The aim of this study was to assess the development of research on neck dissection for OSCC in terms of the historical evolution, current hotspots and future directions, particularly including research trends and frontiers from 2010 to 2019. Literature records related to research on neck dissection for OSCC were retrieved from the Web of Science Core Collection (WoSCC). CiteSpace was used as a tool to perform a bibliometric analysis of this topic. The survey included 2 096 papers. “Otorhinolaryngology” was the most popular research area. The most active institutions and countries were Memorial Sloan Kettering Cancer Center and the USA, respectively. Shah J.P. was the most cited author. Among the six identified “core journals”, Head & Neck ranked first. The top three trending keywords were ‘invasion’, ‘upper aerodigestive’ and ‘negative neck’. ‘D’Cruz AK (2015)’ was the most cited and the strongest burst reference in the last decade. The study evaluated the effect on survival of elective versus therapeutic neck dissection in patients with lateralized early-stage OSCC. The depth of invasion and the management of N0 OSCC were research frontiers in this field. The present study provides a comprehensive bibliometric analysis of research on neck dissection for OSCC, which will assist investigators in exploring potential research directions.

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.

The occult nodal metastasis rate of early tongue cancer (T1-T2): A protocol for a systematic review and meta-analysis

OBJECTIVES

In this study, a meta-analysis was conducted to evaluate the occult lymph node metastasis rate in patients with early-stage (T1-T2) oral tongue squamous cell carcinoma. Also, the correlation between occult lymph node metastasis rate and T2 ratio among T1-T2 or the reported year of each study was analyzed to adjust other confound variables.

STUDY DESIGN

Literature search.

METHODS

A systematic computerized search of the electronic databases was carried out for articles published between January 1, 1980, and December 31, 2018, which reported occult nodal metastasis rate in T1 and T2 (separately) tongue cancer patients. Statistical analysis was performed using Comprehensive Meta Analysis version 3.3.070. Publication bias was assessed by the Egger test and Begg funnel plot method. The correlation between occult nodal metastasis rate and T2 ratio or reported year, respectively, was assessed by meta-regression analysis.

RESULTS

From 19 studies, a total of 1567 cases were included in the meta-analysis. By random effects model, the mean occult cervical lymph node metastasis was 24.4% (95% confidence interval; 0.205-0.248). The meta-regression revealed that the T2 ratio and the reported year of the studies did not have a significant effect on the occult metastasis rate (correlation coefficient = 0.531 and 0.002, respectively, and P = .426 and 0.921, respectively).

CONCLUSION

The meta-analysis revealed that the early-stage oral tongue squamous cell carcinoma had a rate of 24.4% for occult nodal metastasis. The occult nodal metastasis rate was not significantly affected by neither T2 ratio among T1-T2 nor reported year of the studies.

Actin-Associated Gene Expression is Associated with Early Regional Metastasis of Tongue Cancer

OBJECTIVES

We aimed to analyze gene expression profile of tongue cancer associated with early lymph node metastasis using the cancer genome atlas (TCGA) data.

STUDY DESIGN

Basic research.

METHODS

A total of 515 patients with matched RNAseq data of primary tumor and clinical data from TCGA data were extracted. To compare gene expression profile between early T-stage tongue cancer with cervical lymph node metastasis and late T-stage tongue cancer without cervical metastasis, genomic data of following two groups was assessed; 1) group 1: T1/2 and N2/3 (n = 41), 2) group 2: T4 and N0 (n = 65). Using R and limma package in bioconductor program, differentially expressed genes (DEGs) were extracted. Gene ontology and pathway enrichment analysis were performed using the DAVID online tool. FFPE tissue of 285 patients were evaluated for the validation of relevant genes by imunofluorescence (IF) and immunohistochemical (IHC) stain.

RESULTS

A total of 225 DEGs were found, and 50 genes were highly significant with absolute fold change over eight. Gene ontology and pathway enrichment analysis revealed that most of the upregulated genes were associated with actin cytoskeleton and included following genes: ANKRD23, NO3, PDLIM3, MUSTN1, TNNT3, MYBPC1, MB, MYH3, TTN, ACTA1, and ACTC1. When comparing tongue cancer with cN0pN0 vs. pN0pN+ using the total tongue cancer cohort of TCGA, ACTA1 was the only parameter which was associated with hidden lymph node metastasis in T1/2 (P = .019). Perineural invasion was significantly associated with high expression of ACTA1 (P < .001). IF and IHC analysis revealed that actin was overexpressed, while E-cadherin and N-cadherin were not significantly different.

CONCLUSIONS

Actin associated genes, especially overexpression of ACTA1 may be associated with early regional metastasis of tongue cancer.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:813-819, 2021.

Management of the clinically N0 neck in early-stage oral squamous cell carcinoma (OSCC). An EACMFS position paper

Metastasis of oral squamous cell carcinoma (OSCC) to the cervical lymph nodes has a significant impact on prognosis. Accurate staging of the neck is important in order to deliver appropriate treatment for locoregional control of the disease and for prognosis. The management of the neck in early, low volume disease (clinically T₁/T₂ oral cavity tumours) has long been debated. The risk of occult nodal involvement in cT₁/T₂ OSCC is estimated around 20-30%. We describe the natural evolutionary history of OSCC and its patterns of spread and metastasis to the local lymphatic basins. We discuss most published literature and studies on management of the clinically negative neck (cN₀). Particular focus is given to prospective randomized trials comparing the outcomes of upfront elective neck dissection against the observational stance, and we summarize the results of the sentinel node biopsy studies. The paper discusses the significance of the primary tumour histological characteristics and specifically the tumour's depth of invasion (DOI) and its impact on predicting nodal metastasis. The DOI has been incorporated in the TNM staging highlighting its significance in aiding the treatment decision making and this is reflected in world-wide oncological guidelines. The critical analysis of all available literature amalgamates the existing evidence in early OSCC and provides recommendations in the management of the clinically N₀ neck.

Assessment of the Rate of Skip Metastasis to Neck Level IV in Patients With Clinically Node-Negative Neck Oral Cavity Squamous Cell Carcinoma: A Systematic Review and Meta-analysis

Importance

The rate of skip metastasis to neck level IV in patients with clinically node-negative neck (cN0) oral cavity squamous cell carcinoma (OCSCC) remains controversial.

Objective

To provide a high level of evidence using a meta-analysis on the rate of skip metastasis to level IV in this subset of patients.

Data Sources

The Embase, PubMed, and Google Scholar databases were searched for articles published during the period of January 1, 1970, through December 31, 2017, using the following key terms: neck dissection, N0 neck, squamous cell carcinoma, skip metastasis, radical neck dissection, lymph node management, neck metastasis, oral cavity cancer, and tongue cancer. Some terms were also used in combination, and the reference section of each article was searched for additional potentially relevant publications. Data were analyzed from January 8 through 11, 2018.

Study Selection

Inclusion criteria were all cohorts, including from any randomized clinical trial, case-control study, case study, and case report; studies of patients with the histopathologic diagnosis of OCSCC; and studies that differentiated data between skip metastasis and sequential metastasis to neck level IV. Of the 115 articles retrieved from the literature, 11 retrospective studies and 2 prospective randomized clinical trials (n = 1359 patients) were included.

Data Extraction and Synthesis

Meta-analysis of Observational Studies in Epidemiology guidelines were followed. Fixed-effects model and 95% CIs were estimated, and data of included studies were pooled using a fixed-effects model.

Main Outcomes and Measures

Overall proportion of neck involvement and the rate of level IV skip metastasis. Subgroup analysis for primary site and tumor staging.

Results

The rate of level IV involvement in patients with cN0 ranged between 0% and 11.40% with a fixed-effects model of 2.53% (95% CI, 1.64%-3.55%). The rate of skip metastasis ranged from 0% to 5.50% with a fixed-effects model of 0.50% (95% CI, 0.09%-1.11%). The rate of level IV skip metastasis did not increase significantly in cases that involved neck levels I through III. Tumor staging and primary site tumor did not significantly affect the rate of skip metastasis.

Conclusions and Relevance

This meta-analysis showed very low rates of skip metastasis to neck level IV in patients diagnosed with cN0 OCSCC. Encountering an allegedly positive lymph node during neck dissection does not portend high rates of level IV involvement. Supraomohyoid neck dissection is therefore adequate for this subset of patients.

Lingual Lymph Node Metastasis in cT1-2N0 Tongue Squamous Cell Carcinoma: Is It an Indicator for Elective Neck Dissection

Objective: Accurate predictors for occult metastasis in cT1-2N0 tongue squamous cell carcinoma (SCC) remains scarce, the main goal in current study was to evaluate whether there is significant association between lingual lymph node (LLN) metastasis and occult lymph node metastasis as well as whether there is prognostic value of LLN metastasis in early stage tongue SCC.

Methods: Patients with surgically treated primary cT1-2N0 tongue SCC were prospectively enrolled from January 2010 to December 2018. LLNs were dissected independently for pathologic analysis. The main study endpoints were locoregional control survival (LRC) and disease-specific survival (DSS). The Chi-square test and multivariate regression analysis were used to assess the predictors for occult metastasis. The Kaplan-Meier approach and Cox model were used to analyze the potential prognostic factors.

Results: A total of 317 patients were enrolled for analysis. Eighty-eight patients had occult metastasis with a prevalence of 27.8%. LLNs presented in 89 patients, in which 43 patients had LLN metastasis. In the 43 patients with positive LLNs, 20 patients had occult metastasis, in 274 patients with negative LLNs or no LLNs, 68 patients had occult metastasis, the difference was significant (p = 0.012). Further multivariate regression analysis confirmed the independence of LLN metastasis in predicting the occult metastasis. In patients without LLNs, the 5-year LRC rate was 79%, in patients with negative LLNs, the 5-year LRC rate was 78%, in patients with positive LLNs, the 5-year LRC rate was 62%, the difference was significant (p = 0.024). In patients without LLNs, the 5-year DSS rate was 84%, in patients with negative LLNs, the 5-year DSS rate was 74%, in patients with positive LLNs, the 5-year DSS rate was 51%, the difference was significant (p < 0.001), further Cox model confirmed the independence of LLN metastasis in affecting the LRC and DSS.

Conclusions: LLN metastasis is significantly associated with occult neck lymph node metastasis, and decrease the LRC and DSS in early stage tongue SCC.

Elective neck dissection versus observation for early-stage oral squamous cell carcinoma: Systematic review and meta-analysis

INTRODUCTION

Oral squamous cell carcinoma (OSCC) is the seventh most common cancer globally, and has been identified as a growing health concern. This study aims to evaluate the current literature comparing elective neck dissection to observation in the treatment of early-stage tongue SCC, focusing on nodal recurrence, overall survival, disease specific survival statistics from randomised controlled trials comparing the two interventions.

METHODS

Systematic review and meta-analysis was conducted according to PRISMA guidelines. The odds ratio (OR) was used as a summary statistic.

RESULTS

From 8 studies, there was a total of 372 cases of recurrence, 98 (15.1%) in END group and 274 (41.5%) in the Observation group. There was a significantly lower rate of recurrence in the END group compared to observation (OR 0.25, 95% CI 0.16-0.39, I² = 54%, P < 0.00001). END was associated with higher overall survival rates when compared with observation (OR 1.95, 95% CI 1.40-2.73, I² = 14%, P < 0.0001). END was also associated with higher disease-specific survival compared with observation (OR 1.88, 95% CI 1.21-2.93), I² = 47%, P = 0.005), with no significant heterogeneity noted.

CONCLUSIONS

END was associated with significantly lower recurrence rates and higher overall and disease-specific survival compared to a conservative observation approach in early-stage oral SCC with clinically N0 neck.

Significance of depth of invasion determined by MRI in cT1N0 tongue squamous cell carcinoma

Depth of invasion (DOI) can be calculated preoperatively by MRI, and whether MRI-determined DOI can predict prognosis as well as whether it can be used as an indicator of neck dissection in cT1N0 tongue squamous cell carcinoma (SCC) remains unknown. The main goal of the current study was to answer these unknowns. A total of 151 patients with surgically treated cT1N0 tongue SCC were retrospectively enrolled, and MRI-determined DOI was measured based on T1-weighted layers with a 3.0T scan. The Chi-square test was used to evaluate the association between clinical pathologic variables and neck lymph node metastasis, and the factors that were significant in the Chi-square test were then analyzed in a multivariate logistic regression analysis model to determine the independent predictors. The main study endpoints were locoregional control (LRC) and disease-specific survival (DSS), and the Kaplan-Meier method (log-rank test) was used to calculate the LRC and DSS rates. The factors that were significant in univariate analysis were then analyzed in the Cox model to determine the independent prognostic factors. A value of p < 0.05 was considered significant, and all statistical analyses were performed with SPSS 20.0. Occult neck lymph node metastasis was noted in 26 (17.2%) patients, and the ROC curve indicated that the optimal cutoff value of MRI-determined DOI was 7.5 mm for predicting neck lymph node metastasis, with a sensitivity of 86.9%. The factors of lymphovascular invasion, MRI-determined DOI, pathologic DOI, and pathologic tumor grade were significantly associated with the presence of neck lymph node metastasis in univariate analysis, and further logistic regression analysis confirmed the independence of lymphovascular invasion, MRI-determined DOI, and pathologic DOI in predicting neck lymph node metastasis. The 5-year LRC and DSS rates were 84% and 90%, respectively. Cox model analysis suggested the MRI-determined DOI was an independent prognostic factor for both LRC and DSS. Therefore, elective neck dissection is suggested if MRI-determined DOI is greater than 7.5 mm in cT1N0 tongue SCC, and MRI-determined DOI ≥ 7.5 mm indicates additional risk for disease recurrence and cancer-related death.

Elective neck dissection in T1/T2 oral squamous cell carcinoma with N0 neck: essential or not? A systematic review and meta-analysis

INTRODUCTION

Oral squamous cell carcinoma (SCC) is characterized by a high risk of cervical lymph node metastasis with a high incidence of occult metastasis. A strong debate is still present regarding the best treatment for early oral cavity cancer with N0 neck.

OBJECTIVE

The aim of the present study was to compare between the results of elective neck dissection (END) and watchful waiting (observation or therapeutic neck dissection) in patients with early-stage (T1/T2) oral squamous cell carcinoma with N0 neck.

DATA SOURCES

Medline database (https://www.pubmed.com), Google Scholar and Scopus.

PATIENTS AND METHODS

A systematic review and meta-analysis for the evaluation of regional recurrence rate and 5-year survival rate after elective neck dissection (END) or watchful waiting in early oral cancers were conducted. This study included published English medical articles (which met our predetermined inclusion criteria) in the last 30 years, concerning early oral SCC with N0 neck. 24 articles were included (4 randomized studies and 20 observational "retrospective" studies) with a total number of 2190 of patients who underwent END and 1619 who underwent watchful waiting. Regarding the 5-year survival rate, (10) studies were included with a total number of 1211 patients who underwent END and 948 who underwent watchful waiting.

RESULTS

Regarding the regional recurrence rate, (END) was associated with significantly lower risk of recurrence when compared with observation. Regarding the 5-year survival rate, END was associated with a better survival rate than the observational group.

CONCLUSIONS

Elective neck dissection is better than watchful waiting in early (T1/T2) stage oral cavity squamous cell carcinoma with N0 neck, regarding regional recurrence and 5-year survival rate.

Nationwide randomised trial evaluating elective neck dissection for early stage oral cancer (SEND study) with meta-analysis and concurrent real-world cohort

BACKGROUND

Guidelines remain unclear over whether patients with early stage oral cancer without overt neck disease benefit from upfront elective neck dissection (END), particularly those with the smallest tumours.

METHODS

We conducted a randomised trial of patients with stage T1/T2 N0 disease, who had their mouth tumour resected either with or without END. Data were also collected from a concurrent cohort of patients who had their preferred surgery. Endpoints included overall survival (OS) and disease-free survival (DFS). We conducted a meta-analysis of all six randomised trials.

RESULTS

Two hundred fifty randomised and 346 observational cohort patients were studied (27 hospitals). Occult neck disease was found in 19.1% (T1) and 34.7% (T2) patients respectively. Five-year intention-to-treat hazard ratios (HR) were: OS HR = 0.71 (p = 0.18), and DFS HR = 0.66 (p = 0.04). Corresponding per-protocol results were: OS HR = 0.59 (p = 0.054), and DFS HR = 0.56 (p = 0.007). END was effective for small tumours. END patients experienced more facial/neck nerve damage; QoL was largely unaffected. The observational cohort supported the randomised findings. The meta-analysis produced HR OS 0.64 and DFS 0.54 (p < 0.001).

CONCLUSION

SEND and the cumulative evidence show that within a generalisable setting oral cancer patients who have an upfront END have a lower risk of death/recurrence, even with small tumours.

CLINICAL TRIAL REGISTRATION

NIHR UK Clinical Research Network database ID number: UKCRN 2069 (registered on 17/02/2006), ISCRTN number: 65018995, ClinicalTrials.gov Identifier: NCT00571883.

Elective Neck Dissection Versus Observation in Early-Stage (cT1/T2N0) Oral Squamous Cell Carcinoma

Objectives

Whether to perform elective neck dissection (END) or apply the observation (OBS) policy in patients with early‐stage oral squamous cell carcinoma (OSCC) without clinical evidence of cervical lymph node metastasis (cT1/T2N0) remains uncertain. The two most recent meta‐analyses include many studies published before the widespread availability of CT scanning in the 1990s. With the rapid advancement in imaging studies since 1990, the early clinical detection of cervical node metastasis has become more reliable without the need for END or pathological staging. Thus, we conducted a systematic review and meta‐analysis of studies comparing survival outcomes between END and OBS in patients with cT1/T2N0 OSCC.

Methods

We performed a systematic search of MEDLINE, PubMed, and Scopus for retrospective and prospective studies published between January 1, 1990, and January 1, 2018, comparing clinical outcomes between END and OBS in patients with cT1/T2N0 OSCC. Information on population characteristics, study design, overall survival (OS), disease‐specific survival (DSS), and disease‐free survival (DFS) was extracted and estimated. Effect measures for outcomes were hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

Thirteen retrospective and two prospective randomized studies (3,158 patients) met the inclusion criteria. Compared to OBS, END failed to significantly improve OS (HR, 1.02; 95% CI, 0.95–1.09; P = .77; fixed‐effects model), DSS (HR, 1.07; CI, 1.02–1.13; P = .31; fixed‐effects model), and DFS (HR, 0.86; CI, 0.72–1.01; P = .12; random‐effects model).

Conclusions

Our findings indicate that in patients with cT1T2N0 OSCC, the OBS policy can yield markedly similar OS, DSS, and DFS to those resulting from END.

Level of Evidence

2

Can pattern and depth of invasion predict lymph node relapse and prognosis in tongue squamous cell carcinoma

Background

Tongue squamous cell carcinoma (TSCC) is a special type of oral cancer. Cervical lymph node relapse may occur in a large percentage of TSCC patients, which usually indicates poor prognosis. In this cohort study, we focused on the predictive value of the pathological features on cervical lymph node relapse and TSCC prognosis (disease free survival).

Methods

One hundred forty-one TSCC patients staged as T_1–2N₀ were enrolled and categorized. Subjects were followed-up for 60 months. Univariate analysis was performed with Chi-square test for cervical lymph node relapse and Kaplan-Meier survival analysis and log rank P value for patient prognosis; multivariate analysis was also utilized with Cox regression.

Results

In univariate analysis, trabes growth pattern, depth of invasion greater than 4 mm, poor pathological differentiation and neurovascular invasion were considered as risk factors for cervical lymph node relapse and poor prognosis. In multivariate analysis, only patients with trabes growth pattern in the invasive front or depth of invasion larger than 4 mm had a higher risk of metastasis. Elder age group and trabes growth pattern of invasive front were considered as predictors of poor prognosis. Bad habits of smoking and alcohol consumption were related to the higher risk of metastasis.

Conclusion

Trabes growth pattern of invasive front was a potent risk factor for TSCC cervical lymph node relapse and indicated poor prognosis. Preventive therapy including selective neck dissection was thus suggested for certain patients.

Trial registration

Not applicable.

Controversies in relation to neck management in N0 early oral tongue cancer

The standard local treatment for early-stage tongue cancer with no clinical lymph node metastases is partial glossectomy. The frequency of occult lymph node metastasis is ~20-30%. Thus, whether prophylactic neck dissection with glossectomy or glossectomy alone should be performed has been a controversial issue since the 1980s. Both treatments have advantages and disadvantages; however, especially in cases involving prophylactic neck dissection, surgical invasion and complications including the cosmetic disadvantage caused by neck skin incision, accessory nerve paralysis or facial nerve (mandibular marginal branch) paralysis, stiffness of the shoulder or neck and a feeling of neck tightness have been considered issues that could be solved by providing less-invasive treatment to the 70-80% of patients without occult lymph node metastasis. A more accurate preoperative diagnosis and strict follow-up are required to provide minimally invasive treatment while ensuring the therapeutic effect. It is also necessary to narrow down the target based on the risk-benefit balance. The depth of invasion should be considered in cases involving oral cavity malignancies. This was also taken into account in recent revisions of eighth edition of the TNM Classification of Malignant Tumors and it is an important factor for N0 neck management. This review article summarizes previous and recent reports on neck management, focusing on the risk-benefit and future perspectives of the diagnosis and treatment of early-stage oral tongue cancer. This effort is an attempt to establish treatment from the patient's point of view, with the patient's quality of life taken into account.

A decision analysis model for elective neck dissection in patients with cT1-2 cN0 oral squamous cell carcinoma

Neck metastasis from oral squamous cell carcinoma (OSCC) has a significant impact on disease-specific and overall survival. Physical examination and imaging exams are used to stage the neck, but preoperative neck staging cannot reliably differentiate between metastatic and non-metastatic nodes. The decision to perform elective neck dissection (END) should consider the probability of neck metastasis and the harm of unnecessary surgery. We evaluate if this model can be used to decide treatment and the net benefit with different strategies. We reviewed patients treated from January, 1985 to December, 2012. Inclusion criteria were histological diagnosis of OSCC, initial surgery and primary tumour in the oral cavity staged as cT1-2 cN0. Development of a predictive model for metastatic nodes used patients submitted to END. The probability of neck metastasis was calculated and decision curve analysis was performed. We considered two interventions: watchful waiting and END, and two outcomes, regional recurrence and disease-free survival. We developed the model using logistic regression after multiple inputs with neck metastasis as an outcome. The initial model included all demographic and pathological variables. This model has an area under the curve (AUC) of 0.8423, a positive predictive value (PPV) of 70.7% and a negative predictive value (NPV) of 80.2%. We used LASSO for coefficient reduction and variable selection. This model has an AUC of 0.8265 with PPV of 68.3% and NPV of 80.2%. For neck recurrence, the curves of “treat all by watchful waiting” and “treat none by watchful waiting” crossed at the prevalence of neck metastasis. When focusing on disease-free survival, the decision analysis curve shows a pattern where the predictive model provides a net benefit if used to choose treatment from a 20% until a 54% threshold.

Guidelines for the Surgical Management of Oral Cancer: Korean Society of Thyroid-Head and Neck Surgery

Korean Society of Thyroid-Head and Neck Surgery appointed a Task Force to provide guidance on the implementation of a surgical treatment of oral cancer. MEDLINE databases were searched for articles on subjects related to “surgical management of oral cancer” published in English. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. The quality of evidence was rated with use RoBANS (Risk of Bias Assessment Tool for Nonrandomized Studies) and AMSTAR (A Measurement Tool to Assess the Methodological Quality of Systematic Reviews). Evidence-based recommendations for practice were ranked according to the American College of Physicians grading system. Additional directives are provided as expert opinions and Delphi questionnaire when insufficient evidence existed. The Committee developed 68 evidence-based recommendations in 34 categories intended to assist clinicians and patients and counselors, and health policy-makers. Proper surgical treatment selection for oral cancer, which is directed by patient- and subsite-specific factors, remains the greatest predictor of successful treatment outcomes. These guidelines are intended for use in conjunction with the individual patient’s treatment goals.

Clinical analysis of neck node metastasis in oral cavity cancer

Objectives

The purpose of this study was to evaluate the neck node metastasis pattern and related clinical factors in oral cavity cancer patients.

Materials and Methods

In total, 76 patients (47 males, 29 females) with oral squamous cell carcinoma (OSCC) who had no previous malignancies and were not undergoing neoadjuvant concomitant chemoradiotherapy or radiotherapy were selected for analysis.

Results

Occult metastases were found in 8 of 52 patients with clinically negative nodes (cN0, 15.4%). Neck node metastases were found in 17 patients (22.4%). There was a statistically significant relationship between neck node metastasis and T stage (P=0.014) and between neck node metastasis and distant metastasis (Fisher's exact test, P=0.019).

Conclusion

Neck node metastasis was significantly related to tumor size and distant metastasis during follow-up.