Prospective study of ultrasound-guided fine-needle aspiration cytology and sentinel node biopsy in the staging of clinically negative T1 and T2 oral cancer

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

Objectives

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

Methods

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 Exclusion criteria included animal studies, non-English articles, non-availability of full text, and unpublished data.

Results

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

Conclusion

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

Diagnostic accuracy of contrast-enhanced computed tomography in assessing cervical lymph node status in patients with oral squamous cell carcinoma

OBJECTIVE

Accurate preoperative prediction of lymph node (LN) status plays a pivotal role in determining the extension of neck dissection (ND) required for patients with oral squamous cell carcinoma (OSCC). This study aims to evaluate the diagnostic accuracy of contrast-enhanced computed tomography (CT) in detecting LN metastases (LNMs) and to explore clinicopathological factors associated with its reliability.

METHODS

Data from 239 patients with primary OSCC who underwent preoperative CT and subsequent radical surgery involving ND were retrospectively reviewed. Suspicious LNs were categorized into three groups: accentuated (< 10 mm), enlarged (≥ 10 mm), and melted. Statistical analysis encompassing correlation and comparative analysis, and determination of sensitivity, specificity, PPV, and NPV were performed.

RESULTS

Overall, sensitivity was significantly higher in the accentuated LNs group (83.54%) compared to the melted LNs group (39.24%, p < 0.05, t test). Conversely, specificity was significantly higher in the melted LNs group (98.19%) compared to the accentuated LNs group (55.15%, p < 0.05, t test). Accentuated LNs exhibited a false negative rate of 13.00%. False positive rates were 51.80%, 30.26% and 8.82%, respectively. Diagnostic accuracy for detecting LNMs in level IIa and IIb exceeded that of level III. Patients with solely accentuated LNs were more likely to have a small, well-differentiated tumor. However, no distinctions emerged in terms of the occurrence of T4 tumors among the three groups.

CONCLUSION

CT proves sufficient to predict LNMs in patients with OSCC. Looking ahead, the potential integration of artificial intelligence and deep learning holds promise to further enhance the reliability of CT in LNMs detection. However, this prospect necessitates further investigation.

The role of magnetic resonance imaging and computed tomography in oral squamous cell carcinoma patients' preoperative staging

Introduction

The aim of the study was to evaluate the accuracy of MRI and CT with regard to the detection of lymph node metastases based on the data of specific patients with OSCC who received bilateral neck dissection.

Materials and methods

In a retrospective analysis from 01/2014 to 12/2020 patients who underwent primary tumor resection and bilateral neck dissection were evaluated.

Results

174 preoperative MRI (78.74%, N=137) and CT (21.26%, N=37) were correlated with the histopathological findings. CT had a sensitivity of 67% and specificity of 68% (p=0.76). MRI showed an overall sensitivity of 66% and a specificity of 68% (p=0.76). In 52.87% of all cases no differences between cN and pN were found. MRI is the method to overestimate lymph node involvement compared to CT (overestimation in 27% vs. 21.62%).

Conclusion

The current data indicate that MR and CT show poor efficacy in the detection of cervical metastases. Accordingly, attention must be paid to alternatives to correct local staging modalities. The application of structured bilateral neck dissection needs to be questioned.

The Applications and Potential Developments of Ultrasound in Oral Cancer Management

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

ADC Values of Cytologically Benign and Cytologically Malignant 18 F-FDG PET-Positive Lymph Nodes of Head and Neck Squamous Cell Carcinoma

Simple Summary

In squamous cell carcinoma of the head and neck, 18F-fluordeoxyglucose positron emission tomography (FDG-PET), diffusion-weighted magnetic resonance imaging (DW-MRI) and ultrasound-guided fine needle aspiration are commonly used imaging tools for nodal staging (N-staging). Although FDG-PET has good performance in nodal detection, it is still difficult to distinguish between PET-positive reactive and malignant nodes for the purpose of selecting nodes to be aspirated. DW-MRI can help to detect small lymph node metastases, and an inverse correlation with FDG uptake is expected. We found a mild negative correlation between SUVmax and ADC. Comparing the apparent diffusion coefficient (ADC) values between PET-positive and PET-negative nodes, ADC was significantly higher in PET-negative nodes. Whereas no significantly lower ADC value of cytological malignant nodes could be found overall, in the subgroup of non-HPV-related nodes, the ADC values of cytologically malignant PET-positive nodes were significantly lower than in cytologically benign nodes. This finding might be helpful in selecting nodes for puncture.

Abstract

Nodal staging (N-staging) in head and neck squamous cell carcinoma (HNSCC) is essential for treatment planning and prognosis. 18F-fluordeoxyglucose positron emission tomography (FDG-PET) has high performance for N-staging, although the distinction between cytologically malignant and reactive PET-positive nodes, and consequently, the selection of nodes for ultrasound-guided fine needle aspiration cytology (USgFNAC), is challenging. Diffusion-weighted magnetic resonance imaging (DW-MRI) can help to detect nodal metastases. We aim to investigate the potential of the apparent diffusion coefficient (ADC) as a metric to distinguish between cytologically reactive and malignant PET-positive nodes in order to improve node selection criteria for USgFNAC. PET-CT, real-time image-fused USgFNAC and DW-MRI to calculate ADC were available for 78 patients offered for routine N-staging. For 167 FDG-positive nodes, differences in the ADC between cytologically benign and malignant PET-positive nodes were evaluated, and both were compared to the ADC values of PET-negative reference nodes. Analyses were also performed in subsets of nodes regarding HPV status. A mild negative correlation between SUVmax and ADC was found. No significant differences in ADC values were observed between cytologically malignant and benign PET-positive nodes overall. Within the subset of non-HPV-related nodes, ADC_b0-200-1000 was significantly lower in cytologically malignant PET-positive nodes when compared to benign PET-positive nodes. ADC_b0-1000 and ADCb_0-200-1000 were significantly lower (p = 0.018, 0.016, resp.) in PET-negative reference nodes than in PET-positive nodes. ADC was significantly higher in PET-negative reference nodes than in PET-positive nodes. The non-HPV-related subgroup showed significantly (p = 0.03) lower ADC values in cytologically malignant than in cytologically benign PET-positive nodes, which should help inform the node selection procedure for puncture.

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.

Sentinel lymph node biopsy versus elective neck dissection in squamous cell carcinoma of the oral cavity with a clinically N0 neck: Systematic review and meta-analysis of prospective studies

Sentinel lymph node biopsy (SLNB) is an emerging strategy for managing early-stage oral squamous cell carcinoma (SCC) with a clinically N0 (cN0) neck. However, the role of SLNB in this scenario is debatable. Herein, relevant literature was systematically reviewed, and a meta-analysis was performed to evaluate the potential dividends of SLNB compared to elective neck dissection (END) for these patients. The meta-analysis, including six prospective studies, showed comparable results of the two management strategies in terms of regional recurrence (risk ratio [RR] = 0.99; 95% confidence interval [CI], 0.58-1.70), 5-year disease-free survival (RR = 0.99; 95% CI, 0.87-1.11), and 5-year overall survival (RR = 1.01; 95% CI, 0.90-1.13). Fewer adverse events occurred in the SLNB arm than in the END arm (RR = 0.12; 95% CI, 0.02-0.70). Overall, SLNB results in as favorable an oncologic prognosis for patients with cN0 oral SCC as END, while significantly lessening side effects and unnecessary surgeries.

Diagnostic yield of sentinel lymph node biopsy in oral squamous cell carcinoma T1/T2-N0: systematic review and meta-analysis

The objective of this study was to conduct a systematic review and meta-analysis on the efficacy of sentinel lymph node biopsy (SLNB) in T1/T2-N0 oral squamous cell carcinoma (OSCC). A systematic review of the literature on SLNB until March 2019 was conducted. The review was organized according to the PRISMA protocol, considering the following PICO (population, intervention, comparison, outcome) question: What is the sensitivity of sentinel lymph node biopsy in OSCC? 'P' was patients with head and neck squamous cell carcinoma T1/2-N0; 'I' was SLNB; 'C' was neck treated with elective neck dissection and haematoxylin-eosin histopathology; 'O' was sensitivity and specificity. A meta-analysis and meta-regression were performed on the selected studies. The sensitivity of SLNB was up to 88% (95% confidence interval (CI) 72-96%) and specificity was up to 99% (95% CI 96-100%). The area under the summary receiver operating characteristic curve was 0.99 (95% CI 0.98-1.00). In the four studies where immunohistochemistry was performed, both the sensitivity and specificity were higher than in the studies without immunohistochemistry: 93% (95% CI 88-97%) and 98% (95% CI 96-100%), respectively. In conclusion, SLNB is an effective technique for treating patients with some types of stage T1/2-N0 OSCC. Some parameters such as immunohistochemistry could determine the level of diagnostic accuracy.

Detecting cancer metastasis and accompanying protein biomarkers at single cell levels using a 3D-printed microfluidic immunoarray

A low-cost microfluidic microarray capable of lysing cells and quantifying proteins released after lysis was designed and 3D-printed. The array lyses cells on-chip in lysis buffer augmented with a 2s pulse of a sonic cell disruptor. Detection of desmoglein 3 (DSG3), a metastatic biomarker for head and neck squamous cell carcinoma (HNSCC), along with two accompanying HNSCC biomarkers from a single cell lysate of oral cancer cell cultures was demonstrated. A lysis chamber and reagent compartments deliver sample and reagents into detection chambers decorated with capture antibodies immobilized onto inner walls coated with a highly swollen 3D chitosan hydrogel film. Sandwich immunoassays are achieved when captured analytes labeled with biotinylated secondary antibodies, which then capture streptavidin-poly [horse radish peroxidase] (Poly-HRP). Subsequent delivery of super-bright femto-luminol with H2O2 generates chemiluminescence captured with a CCD camera. DSG3 is membrane-bound protein in HNSCC cells of invaded lymph nodes, vascular endothelial growth factor-A (VEGF-A), vascular endothelial growth factor-C (VEGF-C) were positive controls overexpressed into the HNSCC culture medium. Beta-tubulin (β-Tub) was used as a loading control to estimate the number of cells in analyzed samples. Limits of detection (LOD) were 0.10 fg/mL for DSG3, and 0.20 fg/mL for VEGF-A, VEGF-C and β-Tub. Three orders of magnitude semilogarithmic dynamic ranges were achieved. VEGF-A showed high in-cell expression, but VEGF-C had low levels inside cells. The very low LODs enabled quantifying these proteins released from single cells. Strong correlation between results from on-chip cell lysis, conventional off-line lysis and ELISA confirmed accuracy.

Variability in Recommendations for Cervical Lymph Node Pathology for Staging of Canine Oral Neoplasia: A Survey Study

There is no clear guideline regarding the indication for routine lymph node extirpation and pathologic evaluation during staging of canine oral tumors, despite a relatively high reported nodal metastatic rate for select tumor types. It is particularly unclear if clinicians recommend removal of lymph nodes only when there is confirmation of metastasis, defined as the N+ neck, or if elective neck dissection (END) is routinely recommended to confirm the true pathologic metastatic status of lymph nodes in the clinical N0 neck (no evidence of metastasis on clinical staging with diagnostic imaging or cytology). When clinicians are recommending END as a staging tool to confirm nodal status, there is also ambiguity regarding the surgical extent for subsequent histopathologic evaluation. The objective of this cross-sectional survey study was to determine the current recommendations given by practicing specialists regarding lymph node removal for dogs with oral tumors. Overall, 87 responses were obtained from 49 private practices (56%) and 38 academic institutions (44%). Respondents identified as oncologists (44%, N = 38), soft tissue surgeons (40%, N = 35), and dentists (16%, N = 14). Regardless of tumor type and stage, extirpation and histopathology were most commonly recommended in the clinical N+ neck only. The recommendation to routinely perform END in the N0 neck was significantly associated with tumor type. Bilateral removal of the mandibular and retropharyngeal lymph nodes was recommended more often for oral malignant melanoma (OMM) than for oral squamous cell carcinoma (OSCC; p ≤ 0.0039) or for oral fibrosarcoma (OFSA; p ≤ 0.0007). The likelihood of recommending END increased with increasing tumor size. Academic clinicians were significantly (p < 0.01) more likely to recommend END compared to private practitioners for canine T1-T3 OMM, T3 OSCC, T2 OFSA, and MCT. This study highlights the variability in recommendations for lymph node pathology for dogs with oral tumors. While tumor type and size influenced the decision to pursue END, it was not routinely recommended, even for tumor types with a known propensity for metastasis. Prospective studies are warranted to determine the potential diagnostic and therapeutic value of END in the N0 neck in veterinary patients such that a consensus approach can be made.

Usefulness of Sentinel Lymph Node Biopsy for Oral Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

We assessed the diagnostic accuracy of sentinel lymph node biopsy (SLNB) for detecting neck nodal metastasis in early oral squamous cell carcinoma (OSCC) as an alternative to elective neck dissection.

STUDY DESIGN

A systematic search for relevant literature was conducted in the PubMed, SCOPUS, Embase, Web of Science, and Cochrane databases.

METHODS

Two reviewers individually searched the five databases up to November 2019. For studies that met inclusion criteria, data on patient diagnoses were pooled, including true positives, true negatives, false positives, and false negatives. Methodological quality was checked with the Quality Assessment of Diagnostic Accuracy Studies (version 2) tool.

RESULTS

In total, 98 observational or retrospective studies were included. The diagnostic odds ratio of SLNB was 326.165 (95% confidence interval [CI]: 231.477-459.587; I²  = 0%). The area under the summary receiver operating characteristic curve was 0.982. Sensitivity was 0.827 (95% CI: 0.804-0.848), and specificity was 0.981 (95% CI: 0.975-0.986). The correlation between sensitivity and the false positive rate was -0.076, which indicates that heterogeneity did not exist. Subgroup analyses were performed with the subgroups reference test type, publication year, and study type. No significant difference was found within the reference test type subgroup. However, differences within the publication year and study type subgroups were significant, where the retrospective study subgroup was significantly more sensitive and specific than the prospective study subgroup.

CONCLUSION

Results of this meta-analysis imply that the high specificity of SLNB supports its role as a diagnostic tool for patients with clinical tumor stage (CT)1-2 clinically negative (N0) OSCC. More studies should be done to further verify the results of this study.

LEVEL OF EVIDENCE

2a Laryngoscope, 131:E459-E465, 2021.

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 in oral squamous cell carcinoma: Past, present and future

In 1994 a decision analysis, based on the literature and utility ratings for outcome by a panel of experienced head and neck physicians, was presented which showed a threshold probability of occult metastases of 20% to recommend elective treatment of the neck. It was stated that recommendations for the management of the cN0 neck are not immutable and should be reconfigured to determine the optimal management based on different sets of underlying assumptions. Although much has changed and is published in the almost 25 years after its publication, up to date this figure is still mentioned in the context of decisions on treatment of the clinically negative (cN0) neck. Therefore, we critically reviewed the developments in diagnostics and therapy and modeling approaches in the context of decisions on treatment of the cN0 neck. However, the results of studies on treatment of the cN0 neck cannot be translated to other settings due to significant differences in relevant variables such as population, culture, diagnostic work-up, follow-up, costs, institutional preferences and other factors. Moreover, patients may have personal preferences and may weigh oncologic outcomes versus morbidity and quality of life differently. Therefore, instead of trying to establish "the" best strategy for the cN0 neck or "the" optimal cut-off point for elective neck treatment, the approach to optimize the management of the cN0 neck would be to develop and implement models and decision support systems that can serve to optimize choices depending on individual, institutional, population and other relevant variables.

Comparison of SPECT/CT and Planar Lympho-scintigraphy in Sentinel Node Biopsies of Oral Cavity Squamous Cell Carcinomas

Introduction:

Evidence supporting the use of Sentinel node biopsy (SNB) for nodal staging of early oral squamous cell carcinomas (OSCC) appears to be very promising. Pre-operative lymphatic mapping using planar lymphoscinitigraphy (PL) with or without SPECT/CT in the SNB procedure is useful in sentinel node localization and for planning appropriate surgery. Recently, a large prospective multi-centric study evaluating SNB in cutaneous melanoma, breast and pelvic malignancies, demonstrated that adding SPECT to PL leads to surgical adjustments in a considerable number of patients. Our aim of this study was to evaluate the incremental value of additional SPECT/CT over PL alone in SNB for OSCC.

Materials and Methods:

This was a retrospective analysis of 44 patients (40- tongue, 4- buccal mucosa) with T1-T2, clinically N0 oral cavity SCC who underwent sentinel node biopsy procedure. PL and SPECT lymphoscinitigraphy images were compared for pre-operative mapping of sentinel nodes.

Results:

Using a handheld gamma probe, a total of 179 sentinel nodes were harvested, with a mean of 4.06 per patient. PL revealed 75 hotspots with a mean of 1.70 per patient, and SPECT/CT revealed 92 hotspots with a mean of 2.09 per patient. Additional hotpots were identified in 14 patients on SPECT/CT, which included 4 patients, where PL did not detect any sentinel nodes.

Conclusion:

Pre-operative SPECT/CT in addition to planar lympho-scinitigraphy in sentinel node biopsies of oral cavity SCC detects more number of sentinel nodes compared to planar imaging alone. The higher sensitivity of SPECT combined with better anatomical localization using diagnostic CT may further improve the precision of SNB procedure.

Diagnostic Efficacy of Sentinel Lymph Node Biopsy in Early Oral Squamous Cell Carcinoma: A Meta-Analysis of 66 Studies

OBJECTIVES

The diagnostic efficacy of sentinel lymph node biopsy(SLNB) in early oral squamous cell carcinoma(OSCC) still remains controversial. This meta-analysis was conducted to assess the diagnostic value of SLNB in clinically neck-negative T1-2 OSCC.

METHODS

A systematic literature search for relevant literature published up to September 11, 2016 was conducted in PubMed, Embase, Web of Science, Cochrane Library and ClinicalTrials, and the reference lists of eligible studies were examined. Data from different studies were pooled to estimate the summary sentinel lymph node(SLN) identification rate, sensitivity, negative predictive value. Summary receiver operator characteristic curve(SROC) was plotted and area under the SROC curve (AUC) was calculated to evaluate the overall diagnostic efficacy. Threshold effect was assessed with use of the spearman correlation coefficient. Between-study heterogeneity was tested using the Q tests and the I2 statistics. Subgroup analyses were conducted in view of the greater effect of different study characteristics on diagnostic efficacy of SLN. Deeks' funnel plot asymmetry test was performed to evaluate publication bias. Sensitivity analysis was evaluated through omitting studies one by one and comparing the pooled results of random-effects model and fixed-effects model. All analyses were performed using Review Manager (version 5.3.5), Meta-DiSc (version 1.4), Comprehensive Meta Analysis (version 2.0) and STATA (version 12).

RESULTS

66 studies comprising 3566 patients with cT1-2N0 OSCC were included in this meta-analysis. The pooled SLN identification rate was 96.3%(95% CI: 95.3%-97.0%). The pooled sensitivity was 0.87 (95% CI: 0.85-0.89), pooled negative predictive value was 0.94 (95% CI: 0.93-0.95), and AUC was 0.98 (95% CI: 0.97-0.99). Subgroup analyses indicated that SLN assessment with immunohistochemistry(IHC) achieved a significantly higher sensitivity than without IHC.

CONCLUSIONS

This meta-analysis suggests that SLNB has a high diagnostic accuracy in cT1-2N0 oral squamous cell carcinoma, and is an ideal alternative to elective neck dissection. Furthermore, the use of IHC can significantly improve SLNB diagnostic sensitivity for early OSCC.

Neck observation versus elective neck dissection in management of clinical T1/2N0 oral squamous cell carcinoma: a retrospective study of 232 patients

Objective

The management of early-stage (cT1/2N0) oral squamous cell carcinoma (OSCC) remains a controversial issue. The aim of this study was to compare the clinical outcomes of neck observation (OBS) and elective neck dissection (END) in treating patients with cT1/2N0 OSCC.

Methods

A total of 232 patients with cT1/2N0 OSCC were included in this retrospective study. Of these patients, 181 were treated with END and 51 with OBS. The survival curves of 5-year overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) rates were plotted using the Kaplan-Meier method for each group, and compared using the Log-rank test.

Results

There was no significant difference in 5-year OS and DSS rates between END and OBS groups (OS: 89.0% vs. 88.2%, P=0.906; DSS: 92.3% vs. 92.2%, P=0.998). However, the END group had a higher 5-year RFS rate than the OBS group (90.1% vs. 76.5%, P=0.009). Patients with occult metastases in OBS group (7/51) had similar 5-year OS rate (57.1% vs. 64.1%, P=0.839) and DSS rate (71.4% vs. 74.4%, P=0.982) to those in END group (39/181). In the regional recurrence patients, the 5-year OS rate (57.1% vs. 11.1%, P=0.011) and DSS rate (71.4% vs. 22.2%, P=0.022) in OBS group (7/51) were higher than those in END group (9/181).

Conclusions

The results indicated that OBS policy could obtain the same 5-year OS and DSS as END. Under close follow-up, OBS policy may be an available treatment option for patients with clinical T1/2N0 OSCC.

The Indian scenario of head and neck oncology - Challenging the dogmas

Head and neck cancers (HNCs) are the most common malignancies worldwide. Asian populations bear major burden of this disease, with certain unique characteristics. Although significant research in HNCs is ongoing globally, many clinical issues still remain unanswered. We performed a literature search to find noteworthy Indian studies that changed practice of HNC as well as to look for areas for further research in this field. Many randomized controlled trials as well as large patient series are reported in the field of radiotherapy, chemotherapy, and surgical management of HNC. Still, many areas such as palliative therapy, targeted agents, and newer chemotherapeutic agents remain unexplored. Planned collaborative research is need of the hour to provide more evidenced based.

Sentinel lymph node biopsy in oral and oropharyngeal squamous cell carcinoma: current status and unresolved challenges

Because imaging with ultrasound, computed tomography, magnetic resonance imaging or positron emission tomography is unreliable for preoperative lymph node staging of early-stage oral and oropharyngeal squamous cell carcinoma (OSCC), elective neck dissection has been typically performed. The targeted sampling of sentinel lymph nodes (SLN) identified by lymphoscintigraphy and detected by gamma probe has become an effective alternative for the selection of patients for regional nodal resection. With careful consideration to technique, high SLN detection rates have been reported. Advanced techniques including intraoperative handheld gamma camera imaging and freehand single photon emission computed tomography (SPECT) are expected to increase surgical confidence in these procedures. This review gives an update on SLN biopsy in patients with OSCC including clinical standards and controversial aspects.