Comparison of related complications: sentinel node biopsy versus elective neck dissection

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

BACKGROUND

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

METHODS

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

RESULT

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

CONCLUSION

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

Sentinel Lymph Node Biopsy (SLNB) for Early-Stage Head and Neck Squamous-Cell Carcinoma of the Tongue: Twenty Years of Experience at I.N.T. "G.Pascale"

Oral tongue squamous-cell carcinoma (OTSCC) is the most prevalent malignancy in the head and neck region. Lymphatic spread, particularly to cervical lymph nodes, significantly impacts 5-year survival rates, emphasizing the criticality of precise staging. Metastatic cervical lymph nodes can decrease survival rates by 50%. Yet, elective neck dissection (END) in T1-2 cN0 patients proves to be an overtreatment in around 80% of cases. To address this, sentinel lymph node biopsy (SLNB) was introduced, aiming to minimize postoperative morbidity. This study, conducted at the ENT and Maxillofacial Surgery department of the Istituto Nazionale Tumori in Naples, explores SLNB's efficacy in early-stage oral tongue squamous-cell carcinoma (OTSCC). From January 2020 to January 2022, 122 T1/T2 cN0 HNSCC patients were enrolled. Radioactive tracers and lymphoscintigraphy identified sentinel lymph nodes, aided by a gamma probe during surgery. Results revealed 24.6% SLN biopsy positivity, with 169 SLNs resected and a 21.9% positivity ratio. The study suggests SLNB's reliability for T1-2 cN0 OTSCC patient staging and early micrometastasis detection.

Lymphatic drainage of sinonasal malignancies and the role of sentinel node biopsies

BACKGROUND

Locoregional recurrence is a critical factor in the prognosis of sinonasal malignancies. Due to the rarity of these tumours, as well as the heterogeneity of histologies and anatomical subsites, there is little evidence regarding the rate and location of regional metastases in sinonasal malignancies. Elective regional lymph node dissection in the therapy of sinonasal malignancies has become controversial. On the one hand, elective regional lymph node dissection is considered to be an overtreatment in the cN0 cases. On the other hand, undetected occult lymphatic metastases are associated with a poor prognosis. In this study, we discuss the role of sentinel lymph node biopsy as a minimally invasive procedure in the treatment of sinonasal malignancies based on our two years of practical experience and the currently available data.

RESULTS

This is a descriptive, monocentric, retrospective study, including 20 cases of cN0 malignant sinonasal neoplasm, that underwent a surgical therapy between 2020 and 2022. The following aspects were investigated: tumour entity, localisation of the primary tumour, tumoral stage, localisation of the sentinel lymph nodes, and postoperative complications. Squamous cell carcinoma was the most frequently diagnosed tumour entity (50%), followed by adenocarcinoma (20%) and malignant melanoma (15%), adenoid cystic carcinoma and mucoepidermoid carcinoma. Sentinel lymph nodes were most frequently found in the ipsilateral neck region I (45%), followed by the ipsilateral neck region II (40%). In all cases, the removed lymph nodes were free of malignancy. There were no postoperative complications due to lymph node biopsy. There were no recurrences during the study period.

CONCLUSION

Sentinel node biopsy could add more safety to the management of cN0 sinonasal malignancies due to its low morbidity. Whether SNB could provide an alternative to elective neck dissection in the management of SNM should be investigated in further studies.

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.

Summary of Japanese clinical practice guidelines for head and neck cancer - 2022 update edited by the Japan society for head and neck cancer

The aim of the "Japanese Clinical Practice Guidelines for Head and Neck Cancer - 2022 Update" is to review the latest evidence regarding head and neck cancer and to present the current standard approaches for diagnosis and treatment. These evidence-based recommendations were created with the consensus of the Guideline Committee, which is composed of otorhinolaryngologists and head and neck surgeons, together with radiologists, radiation oncologists, medical oncologists, plastic surgeons, dentists, palliative care physicians, and rehabilitation physicians. These guidelines were created by the Clinical Practice Guideline Committee of the Japan Society for Head and Neck Cancer based on the "Head and Neck Cancer Treatment Guidelines 2018 Edition," and the revised draft was compiled after evaluation by the Assessment Committee and public comments. The 'Clinical questions and recommendations' section consists of 13 categories, and 59 clinical questions are described in total. Here we describe 6 clinical questions specific to other sets of guidelines with recommendations and comments.

Foregoing elective neck dissection for elderly patients with oral cavity squamous cell carcinoma

OBJECTIVE

Elective neck dissection (END) improves outcomes among clinically node-negative patients with oral cavity squamous cell carcinoma (OCSCC). However, END is of questionable value, considering the potentially higher comorbidities and operative risks in elderly patients.

METHODS

A retrospective review of all patients older than 65 years of age who were treated for OCSCC at a tertiary care centre between 2005 and 2020 was conducted.

RESULTS

Fifty-three patients underwent primary tumour resection alone, and 71 had simultaneous END. Most primary tumours were located on the mobile tongue. The patients who did not undergo END had a higher mean age (81.2 vs. 75.1 years, P < 0.00001), significantly shorter surgeries, and shorter hospitalizations. Occult cervical metastases were found in 24% of the patients who underwent END. The two groups showed no significant differences in overall survival or recurrence rates. Similar results were shown in a subpopulation analysis of patients older than 75 years.

CONCLUSION

Foregoing END in elderly patients with no clinical evidence of neck metastases did not result in lower survival rates or higher recurrence rates.

Sentinel lymph node biopsy versus elective neck dissection in management of the clinically negative (cN0) neck in patients with oral squamous cell carcinoma: A systematic review and meta-analysis

Oral squamous cell carcinoma (OSCC) is the most prevalent type of head and neck cancer, and lymph node metastasis is a crucial prognostic factor that has a direct correlation with the survival rate. The standard procedure for managing clinically negative (cN0) neck in OSCC patients is elective neck dissection (END), but it can lead to various complications that affect the patient's quality of life. Therefore, medical professionals are exploring the use of the sentinel lymph node biopsy (SLNB) to manage cN0 neck in OSCC patients. The aim of this systematic review and meta-analysis was to compare the overall survival (OS) and disease-free survival (DFS) of patients undergoing SLNB and END in the surgical management of early cN0 neck in OSCC patients. To conduct this study, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was used to report the systematic reviews. The study included all comparative clinical studies, including randomized clinical trials (RCTs), clinical perspective studies, and retrospective studies that compared END to SLNB for early cN0 neck in OSCC patients. The hazard ratio (HR) and risk ratio (RR) with 95% confidence interval (CI) were calculated using comprehensive meta-analysis. The primary outcome variables were OS, DFS, and disease-specific survival (DSS). The secondary outcome variable was the nodal recurrence rate without local or distant metastasis. The GRADE system was used to assess the evidence's certainty. The meta-analysis included 12 clinical studies, comprising three RCTs and seven non-RCTs. The results showed no statistically significant difference between END and SLNB concerning OS (HR = 0.993, CI: 0.814 to 1.211, P = 0.947, low-quality evidence), DFS (HR = 0.705, CI: 0.408 to 1.29, P = 0.21, low-quality evidence), and nodal recurrence (RR = 1.028, CI: 0.969 to 1.090, P = 0.907, low-quality evidence). Additionally, SLNB was non-inferior to END regarding DSS (RR = 1.028, CI: 0.969 to 1.090, P = 0.907, low-quality evidence). In conclusion, this research affirms the safety and precision of SLNB as a means to stage cN0 OSCC patients, with outcomes that are comparable to END in terms of survival and nodal recurrence. Nevertheless, it's crucial to acknowledge that the quality of evidence in this study was relatively low. Therefore, additional RCTs comparing END to SLNB are warranted to validate these results and offer more robust guidance for managing cN0 OSCC patients.

Health-related quality of life, functional outcomes, and complications after sentinel lymph node biopsy and elective neck dissection in early oral cancer: A systematic review

BACKGROUND

Elective neck dissection improves survival in early oral cancer. Sentinel lymph node biopsy may also do this with less morbidity. This systematic review compared health-related quality of life, functional outcomes, and complications after sentinel lymph node biopsy and elective neck dissection in early oral cancer.

METHODS

PRISMA guidelines were followed. Thirteen studies met inclusion criteria.

RESULTS

Results favoring sentinel lymph node biopsy were found in complications, scar length and appearance, length of hospital stay, time to drain removal, and objective shoulder measures at timepoints up to 12 months. Where differences in health-related quality of life were found, methodological issues make their clinical significance questionable.

CONCLUSIONS

Sentinel lymph node biopsy was associated with fewer complications and statistically better outcomes in a number of physical measures. There is as yet no strong evidence to suggest it is associated with better health-related quality of life outcomes. While a number of health-related quality of life outcome measures show promise, their interpretation is hampered by methodological concerns. Further rigorous research is required to address this.

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.

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

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

Systematic review of head and neck lymphedema assessment

Head and neck lymphedema (HNL) is an increasingly recognized complication of head and neck cancer and its treatment. However, no consensus exists on the "gold-standard" assessment tool for the purposes of diagnosis, classification, or monitoring of HNL. We conducted a systematic review of the literature regarding HNL assessment to determine the optimal method/s of assessment for patients with HNL. A review of publications between January 2000 and September 2021 was undertaken on four electronic databases. Studies were excluded if no clear assessment method of HNL was documented. Sixty-seven articles were included in the study. A wide range of assessment methods for HNL have been reported in the literature. For the purposes of diagnosis and classification of physical findings, computed tomography (CT) appears the most promising tool available for both external and internal HNL. In terms of monitoring, ultrasound appears optimal for external HNL, while a clinician-reported rating scale on laryngoscopy is the gold standard for internal HNL. Patient-reported assessment must be considered alongside objective methods to classify symptom burden and monitor improvement with treatment.

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.

Oxygen Imaging for Non-Invasive Metastasis Detection

Sentinel lymph node (SLN) biopsy is an integral part of treatment planning for a variety of cancers as it evaluates whether a tumor has metastasized, an event that significantly reduces survival probability. However, this invasive procedure is associated with patient morbidity, and misses small metastatic deposits, resulting in the removal of additional nodes for tumors with high metastatic probability despite a negative SLN biopsy. To prevent this over-treatment and its associated morbidities for patients that were truly negative, we propose a tissue oxygen imaging method called Photoacoustic Lifetime Imaging (PALI) as an alternative or supplementary tool for SLN biopsy. As the hyper-metabolic state of cancer cells significantly depresses tissue oxygenation compared to normal tissue even for small metastatic deposits, we hypothesize that PALI can sensitively and specifically detect metastases. Before this hypothesis is tested, however, PALI's maximum imaging depth must be evaluated to determine the cancer types for which it is best suited. To evaluate imaging depth, we developed and simulated a phantom composed of tubing in a tissue-mimicking, optically scattering liquid. Our simulation and experimental results both show that PALI's maximum imaging depth is 16 mm. As most lymph nodes are deeper than 16 mm, ways to improve imaging depth, such as directly delivering light to the node using penetrating optical fibers, must be explored.

Sentinel Lymph Node Biopsy Versus Elective Node Dissection in Stage cT1-2N0 Oral Cavity Cancer

OBJECTIVE

To compare overall survival (OS) and disease-free survival (DFS) between sentinel lymph node biopsy (SNB) and elective neck dissection (END) in the surgical management of cT1-2N0 oral cavity squamous cell carcinoma (OCSCC).

METHODS

English full-text articles were searched in PubMed and Embase on May 9, 2021. Articles had to compare SNB with END in cT1-T2N0 OCSCC patients; report hazard ratios (HRs), Kaplan-Meier curves, or P-values with total number of events for survival outcomes; be from a clinical trial, cohort, or case-control study. Two reviewers reviewed articles and a third settled disagreements. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Risk of Bias in Non-randomized Studies of Interventions tool and revised Cochrane risk-of-bias tool for randomized trials were used. The generic inverse variance method with a random-effect model was used for meta-analysis.

RESULTS

Ten studies, five retrospective, three prospective, and two randomized controlled trials, were included (total number of patients [n] = 10,498, END n = 9102, SNB n = 1396). No significant differences were found in OS (HR = 0.92; 95% confidence interval [CI]: 0.65-1.31) or DFS (HR = 0.70; 95% CI: 0.41-1.20). Heterogeneity was not detected in pooled OS analysis (P = .18; I²  = 30%), but was in pooled DFS analysis (P = .003; I²  = 66%).

CONCLUSIONS

No statistically significant differences in OS or DFS were observed between SNB and END in cT1-2N0 OCSCC, suggesting that SNB might be an alternative to END in the management of early-stage, clinically node-negative OCSCC. Laryngoscope, 2021.

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.

Sentinel Lymph Node Biopsy in Early Stages of Oral Squamous Cell Carcinoma Using the Receptor-Targeted Radiotracer 99mTc-Tilmanocept

Neck management in patients with early-stage, clinically node-negative oral squamous cell carcinoma (OSCC) remains a matter of discussion. Sentinel lymph node biopsy (SLNB) represents a treatment alternative to avoid elective neck dissection (END) in this cohort and different protocols and tracers exist. Here we present the clinical outcome of SLNB using ^99mTc-tilmanocept in a two-day protocol in patients suffering from early-stage OSCC. A total of 13 patients (males: 6; females: 7; mean age: 65.7 years, ranging from 47 to 89 years) were included in this study. Most of the patients suffered from an OSCC of the floor of mouth (n = 6), followed by tongue (n = 5) and upper alveolar crest/hard palate (n = 2). Sentinel lymph nodes (SLNs) were successfully identified in all cases (range: 1–7). The average length of hospital stay was 4.7 days (range: 3–8 days) and mean duration of surgical intervention was 121 min (range: 74–233 min). One patient who suffered from an OSCC of the tongue was sentinel lymph node positive (SLN+). The mean follow-up for all sentinel lymph node negative (SLN-) patients (n = 12) was 20.3 months (range: 10–28 months). No local or nodal recurrences were observed within the observation period. In our patient cohort, SLNB using ^99mTc-tilmanocept in a two-day protocol proved to be a reliable and safe staging method for patients suffering from early-stage, clinically node-negative OSCC. These results and their possible superiority to colloid tracers have to be confirmed in a prospective randomized controlled study.

The prognostic role of the pre-treatment neutrophil to lymphocyte ratio (NLR) and tumor depth of invasion (DOI) in early-stage squamous cell carcinomas of the oral tongue

The appropriate surgical management of early-stage oral tongue squamous cell carcinoma (OTSCC) remains a debated topic. The aim of this study is to investigate the role of the pre-treatment neutrophil to lymphocyte ratio (NLR) and tumor depth of invasion (DOI) in predicting the presence of occult neck metastases in early-stage OTSCC. A retrospective analysis of patients affected by early-stage (cT1-T2 cN0) OTSCC who were submitted to elective neck dissection (END) was performed. Tumors were classified retrospectively according to the 8th TNM classification, the DOI was assessed on the pre-operative magnetic resonance imaging, and the pre-treatment NLR was calculated for each patient. A logistic regression model to estimate the probability π (x) of cervical metastases by studying the NLR and DOI was carried out. Next, the correlation between the two variables, the NLR and DOI, was preliminarily studied. A cohort of 110 patients was analyzed (mean age, 62 years old; male to female ratio 1.2:1). The patients were staged as cT1 in 53 cases and cT2 in 57 cases. A DOI greater than 5.4 mm and a NLR greater than 2.93 are associated with an increased risk of presenting occult cervical metastases. Furthermore, the variables NLR and DOI are linearly associated with a positive correlation, proved by Spearman's rank correlation coefficient rho of 0.64, with a unitary increase in the DOI of 1 mm directly associated with an increase of 0.47 in the NLR. The DOI and NLR can be effectively used to predict the occurrence of occult neck metastasis and therefore to plan an END in early-stage OTSCC.

Sentinel lymph node biopsy versus elective neck dissection: long-term oncologic outcomes in clinically node-negative tongue cancer

Objectives

The aim of this study was to compare the long-term oncologic outcomes of sentinel lymph node biopsy (SLNB) versus elective neck dissection (END) in clinically node-negative (cN0) tongue cancer.

Methods

This was a retrospective cohort study of patients with cN0 tongue cancer from a single institution, including 91 patients in the SLNB group and 120 patients in the END group.

Results

The overall recurrence rate showed no significant difference between the two groups. The regional control rate was also comparable between the two groups (P=0.490). The 5-year recurrence-free survival (RFS) was slightly better in the SLNB group than in the END group (P=0.427). The 5-year overall survival (OS) rate was 89.9% in the SLNB group versus 91.9% in the END group (P=0.737). In a propensity-matched subgroup analysis, the type of neck management did not affect RFS or OS.

Conclusion

SLNB showed non-inferior oncologic outcomes compared to END in patients with cN0 tongue squamous cell carcinoma.

Novel Diagnostic Approaches for Assessment of the Clinically Negative Neck in Head and Neck Cancer Patients

In head and neck cancer, the presence of nodal disease is a strong determinant of prognosis and treatment. Despite the use of modern multimodality diagnostic imaging, the prevalence of occult nodal metastases is relatively high. This is why in clinically node negative head and neck cancer the lymphatics are treated “electively” to eradicate subclinical tumor deposits. As a consequence, many true node negative patients undergo surgery or irradiation of the neck and suffer from the associated and unnecessary early and long-term morbidity. Safely tailoring head and neck cancer treatment to individual patients requires a more accurate pre-treatment assessment of nodal status. In this review, we discuss the potential of several innovative diagnostic approaches to guide customized management of the clinically negative neck in head and neck cancer patients.

What is the role of sentinel lymph node biopsy in the management of oral cancer in 2020?

Approximately 70–80% of patients with cT1-2N0 oral squamous cell carcinoma (OSCC) ultimately prove to have no cancer in the cervical lymphatics on final pathology after selective neck dissection. As a result, sentinel lymph node biopsy (SLNB) has been adopted during the last decade as a diagnostic staging method to intelligently identify patients who would benefit from formal selective lymphadenectomy or neck irradiation. While not yet universally accepted, SLNB is now incorporated in many national guidelines. SLNB offers a less invasive alternative to elective neck dissection (END), and has some advantages and disadvantages. SLNB can assess the individual drainage pattern and, with step serial sectioning and immunohistochemistry (IHC), can enable the accurate detection of micrometastases and isolated tumor cells (ITCs). Staging of the neck is improved relative to END with routine histopathological examination. The improvements in staging are particularly notable for the contralateral neck and the pretreated neck. However, for floor of mouth (FOM) tumors, occult metastases are frequently missed by SLNB due to the proximity of activity from the primary site to the lymphatics (the shine through phenomenon). For FOM cancers, it is advised to perform either elective neck dissection or superselective neck dissection of the preglandular triangle of level I. New tracers and techniques under development may improve the diagnostic accuracy of SLNB for early-stage OSCC, particularly for FOM tumors. Treatment of the neck (either neck dissection or radiotherapy), although limited to levels I–IV, remains mandatory for any positive category of metastasis (macrometastasis, micrometastasis, or ITCs). Recently, the updated EANM practical guidelines for SLN localization in OSCC and the surgical consensus guidelines on SLNB in patients with OSCC were published. In this review, the current evidence and results of SLNB in early OSCC are presented.

Selective Neck Dissection in Oral Cavity Cancer Is Not Without Morbidity

The objective of this study is to analyze the morbidity of selective neck dissection (SND) in oral cavity squamous cell carcinoma (OCSCC). This is a cross-sectional study of 106 consecutive patients with T1 and T2 (AJCC seventh edition) stage cancers. Morbidity in terms of scar characteristics, cervical lymphedema, sensation, shoulder dysfunction, and smile asymmetry were analyzed. Scar outcomes were inferior in terms of poor complexion in 15 patients (14.2%), poor texture in 25 patients (23.6%), limited skin movement in 9 patients (8.5%), soft tissue deficit in 13 patients (12.3%), and lymphedema in 14 patients (13.2%). Smile asymmetry was seen in 29.2%. Shoulder dysfunction was seen in 7.5%. Patients who received adjuvant treatment had significant scar issues (p = 0.001), lymphedema (p < 0.001), and sensory issues (p = 0.003). SND in OCSCC is not without morbidity. Smile asymmetry was the commonest problem. Patients who got adjuvant treatment had significantly more morbidity.

Long term-follow-up multicenter feasibility study of ICG fluorescence-navigated sentinel node biopsy in oral cancer

In the current study, the utility of sentinel node (SN) identification using indocyanine green (ICG) was investigated for oral cancers in the clinical N0 stage. The current study was a prospective, multicentre, phase II clinical trial that was conducted in Japan. A total of 18 patients were included. Before surgery, the patients underwent lymphoscintigraphy to map the SNs. During surgery, radioactive isotope (RI) mapping was used to detect the SNs, and ICG was subsequently injected. ICG mapping of the SNs was then performed through the skin. The primary tumour was resected, and a neck flap was elevated for neck dissection, followed by SN biopsy (SNB) using RI or ICG mapping. With the RI method, a total of 63 SNs were detected. Among these SNs, 8 (12.7%) were positive for metastasis, including those with isolated tumour cells (ITCs). The median number of SNs per patient identified by SNB was 4. With the ICG method, a total of 67 SNs were detected. Among these SNs, 7 (10.4%) were positive for metastasis, including those with ITCs. The median number of SNs per patient identified by SNB was 4 (range, 1-6). The 5-year overall survival (OS) of all patients was 83.3%, and the 5-year disease-free survival (DFS) of all patients was 76.7%. The neck compression technique is a simple method that can be used to facilitate surgical procedures of ICG fluorescence navigated SNB for head and neck cancer.

Elective Neck Dissection or Sentinel Lymph Node Biopsy in Early Stage Oral Cavity Cancer Patients: The Dutch Experience

Background: Sentinel lymph node biopsy (SLNB) has been introduced as a diagnostic staging modality for detection of occult metastases in patients with early stage oral cancer. Comparisons regarding accuracy to the routinely used elective neck dissection (END) are lacking in literature. Methods: A retrospective, multicenter cohort study included 390 patients staged by END and 488 by SLNB. Results: The overall sensitivity (84% vs. 81%, p = 0.612) and negative predictive value (NPV) (93%, p = 1.000) were comparable between END and SLNB patients. The END cohort contained more pT2 tumours (51%) compared to the SLNB cohort (23%) (p < 0.001). No differences were found for sensitivity and NPV between SLNB and END divided by pT stage. In floor-of-mouth (FOM) tumours, SLNB had a lower sensitivity (63% vs. 92%, p = 0.006) and NPV (90% vs. 97%, p = 0.057) compared to END. Higher disease-specific survival (DSS) rates were found for pT1 SLNB patients compared to pT1 END patients (96% vs. 90%, p = 0.048). Conclusion: In the absence of randomized clinical trials, this study provides the highest available evidence that, in oral cancer, SLNB is as accurate as END in detecting occult lymph node metastases, except for floor-of-mouth tumours.

Sentinel lymph node biopsies in early stage oral and oropharyngeal carcinoma: a retrospective single-centre experience

The aim of this retrospective study was to analyse a consecutive series of patients with oral and oropharyngeal carcinoma who had had sentinel lymph node biopsy (SLNB) at our hospital during 2008-2017. A total of 70 patients with clinically and radiologically confirmed primary oral (n=67) or oropharyngeal (n=3) carcinoma, with no signs of metastatic lymph nodes preoperatively (clinically N0) were included. Patients' clinical and personal data, characteristics of the tumours, sentinel lymph node (SLN) status and outcomes were recorded. Eight patients had invaded SLN. Two patients with clear sentinel lymph node biopsies had recurrences in the cervical lymph nodes with no new primary tumour as origin. The negative predictive value (NPV) and sensitivity for SLNB were 97% and 80%, respectively. The depth of invasion was an individual predictor for cervical lymph node metastasis (p=0.043). Single photo emission computed tomography (SPECT) detected fewer SLN in patients with invaded lymph nodes than in patients with clear lymph nodes (p=0.018). Our data support the use of SLNB as a minimally invasive method for staging the cervical lymph nodes among patients with cN0 oral and oropharyngeal carcinoma. Our results further confirm that greater depth of invasion is associated with cervical lymph node metastases.

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.

Efficacy of adjuvant chemotherapy with S-1 in stage II oral squamous cell carcinoma patients: A comparative study using the propensity score matching method

It has been reported that 20% of early-stage oral squamous cell carcinoma (OSCC) patients treated with surgery alone (SA) may exhibit postoperative relapse within 2–3 years and have poor prognoses. We aimed to determine the safety of S-1 adjuvant chemotherapy and the potential differences in the disease-free survival (DFS) between patients with T2N0 (stage II) OSCC treated with S-1 adjuvant therapy (S-1) and those treated with SA. This single-center retrospective cohort study was conducted at Kumamoto University, between April 2004 and March 2012, and included 95 patients with stage II OSCC. The overall cohort (OC), and propensity score-matched cohort (PSMC) were analyzed. In the OC, 71 and 24 patients received SA and S-1, respectively. The time to relapse (TTR), DFS, and overall survival were better in the S-1 group, but the difference was not significant. In the PSMC, 20 patients each received SA and S-1. The TTR was significantly lower in the S-1 group than in the SA group, while the DFS was significantly improved in the former. S-1 adjuvant chemotherapy may be more effective than SA in early-stage OSCC.

Magnetic detection of sentinel nodes in oral squamous cell carcinoma by means of superparamagnetic iron oxide contrast

The aim was to evaluate sentinel node detection capacity by means of a magnetic probe in 11 patients with oral squamous cell carcinoma at stages T1-T2 received submucosal injections of a superparamagnetic iron oxide contrast agent (SPIO). A magnetic probe was used for sentinel node biopsy. The use of SPIO and magnetic probes in the early stages of oral cancer may offer an alternative to conventional radioisotope techniques and/or elective neck dissection.

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.

Nanotechnology in Oral Cavity Carcinoma: Recent Trends and Treatment Opportunities

Oral cavity carcinoma (OCC) remains an ongoing public health problem. Emerging nanotechnology provides alternative treatment approaches. This review covers the up-to-date literature in the human OCC treatment field. We explored the growing body of evidence to reveal novel and highly promising diagnostic and therapeutic applications of nanotechnology in this field. Various types of nanoparticles have been tested for applications in OCC. Imaging modalities in addition to nanocarriers are discussed. The encouraging contribution of lymphotropic nanoparticles contrast in the diagnosis of metastatic cervical lymph nodes needs to be confirmed. The development of the sentinel lymph node procedure and photodynamic therapy may lead to breakthrough therapies in order improve clinical outcomes and quality of life. In this perspective, cancer nanotechnology has the potential to revolutionize the treatment of OCC patients.

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.

Management of the Neck in Squamous Cell Carcinoma of the Oral Cavity and Oropharynx: ASCO Clinical Practice Guideline

PURPOSE

The aim of the current work is to provide evidence-based recommendations to practicing physicians and others on the management of the neck in patients with squamous cell carcinoma of the oral cavity and oropharynx.

METHODS

ASCO convened an Expert Panel of medical oncology, surgery, radiation oncology, and advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 1990 through 2018. Outcomes of interest included survival, regional disease control, neck recurrence, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 124 relevant studies to inform the evidence base for this guideline. Six clinical scenarios were devised; three for oral cavity cancer and three for oropharynx cancer, and recommendations were generated for each one.

RECOMMENDATIONS

For oral cavity cancers, clinical scenarios focused on the indications for and the hallmarks of a high-quality neck dissection, indications for postoperative radiotherapy or chemoradiotherapy, and whether radiotherapy alone is sufficient elective treatment of an undissected neck compared with high-quality neck dissection. For oropharynx cancers, clinical scenarios focused on hallmarks of a high-quality neck dissection, factors that would favor operative versus nonoperative primary management, and clarifying criteria for an incomplete response to definitive chemoradiation for which salvage neck dissection would be recommended. Consensus was reached and recommendations were made for all six clinical scenarios. Additional information is available at www.asco.org/head-neck-cancer-guidelines .

Topographical distribution of sentinel nodes and metastases from T1-T2 oral squamous cell carcinomas

OBJECTIVE

The objective is to investigate the topographical distribution of sentinel nodes (SNs) and lymph node metastases in T1-2cN0 oral squamous cell carcinomas (OSCCs).

METHODS

The study entailed a prospective enrolment of 220 patients with clinical T1-2N0 OSCCs who underwent preoperative lymphoscintigraphy (LSG) followed by gamma probe-guided sentinel lymph node biopsy (SLNB). Patients with positive SNs were treated with completion neck dissection. Excised lymph nodes were grouped into the neck level according to the international guidelines.

RESULTS

The SN detection rate by LSG was 99.1%. Patients with midline tumours had bilateral lymphatic drainage on LSG in 15/21 (71.5%). There were 45/199 (22.6%) patients with lateralised tumours that had unexpected bilateral or contralateral drainage patterns on LSG. Fifty-five patients (25.0%) were SLNB positive, and metastases were found in 72/781 (9.2%) of the excised SNs. Metastatic involvement of neck level IV was rare and only observed in patients with anterior tongue cancer. No patients had level V involvement. Eleven patients developed isolated cervical recurrences, with no new primary tumour as origin. The SLNB procedure ensured an overall sensitivity of 83.3% and a negative predictive value of 93.3%.

CONCLUSION

Completion neck dissection of level I-III in SLNB-positive patients might be sufficient in most patients with OSCC except patients with anterior tongue cancer, but further studies are needed to support this potential therapeutic algorithm. Our study showed that SLNB was helpful in clarifying unexpected bilateral or contralateral metastatic drainage patterns. In our cohort, 8/55 patients with occult metastasis would have been missed by elective neck dissection of the ipsilateral neck.

Controversies in Oral and Maxillofacial Oncology

Imaging studies are essential components of tumor diagnosis, staging, assessing tumor response to neoadjuvant and adjuvant therapies, and postoperative surveillance on completion of definitive treatment. Treatment of early stage clinically node negative oral cavity squamous cell carcinoma is controversial. Approximately 3% of all head and neck tumors arise within the parotid gland and most often within the superficial lobe, lateral to the facial nerve; about 80% are benign and most are pleomorphic adenoma. In patients with dry eyes failing multiple other treatment modalities and facing ongoing pain and loss of vision, microvascular transplant of the submandibular gland is a viable option.

Pre-treatment Neutrophil-to-Lymphocyte Ratio as a predictor for occult cervical metastasis in early stage (T1-T2 cN0) squamous cell carcinoma of the oral tongue

BACKGROUND

Optimum management of clinically negative neck (cN0) remains controversial in early stage (T1-T2) squamous cell cancer of the oral tongue (OTSCC). The purpose of this study was to investigate the value of pre-treatment Neutrophil-to lymphocyte ratio (NLR) in predicting occult cervical metastasis in stage I and II OTSCC.

METHODS

We carried out a retrospective chart review on 110 patients suffering from early stage OTSCC who were surgically treated with tumour excision and elective neck dissection (END). Our cohort was divided in pN+ and pN0 groups basing on histopathological examination after elective neck dissection. For each patient pre-treatment NLR was calculated.

RESULTS

A statistically significant relationship between high levels of pre-treatment NLR and probability rate for neck occult metastases (0.000496 p-value) has been found. On our model the cut-off value was set for NLR >2.93. Above this level the probability to finding metastasis in a clinically negative neck increases exponentially.

CONCLUSION

These preliminary results offer clinicians an easily obtainable tool to stratify patients based on risks of metastatic node in whom END could be indicated.

Sensitivity and Specificity of Cetuximab-IRDye800CW to Identify Regional Metastatic Disease in Head and Neck Cancer

Purpose: Comprehensive cervical lymphadenectomy can be associated with significant morbidity and poor quality of life. This study evaluated the sensitivity and specificity of cetuximab-IRDye800CW to identify metastatic disease in patients with head and neck cancer.Experimental Design: Consenting patients scheduled for curative resection were enrolled in a clinical trial to evaluate the safety and specificity of cetuximab-IRDye800CW. Patients (n = 12) received escalating doses of the study drug. Where indicated, cervical lymphadenectomy accompanied primary tumor resection, which occurred 3 to 7 days following intravenous infusion of cetuximab-IRDye800CW. All 471 dissected lymph nodes were imaged with a closed-field, near-infrared imaging device during gross processing of the fresh specimens. Intraoperative imaging of exposed neck levels was performed with an open-field fluorescence imaging device. Blinded assessments of the fluorescence data were compared to histopathology to calculate sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV).Results: Of the 35 nodes diagnosed pathologically positive, 34 were correctly identified with fluorescence imaging, yielding a sensitivity of 97.2%. Of the 435 pathologically negative nodes, 401 were correctly assessed using fluorescence imaging, yielding a specificity of 92.7%. The NPV was determined to be 99.7%, and the PPV was 50.7%. When 37 fluorescently false-positive nodes were sectioned deeper (1 mm) into their respective blocks, metastatic cancer was found in 8.1% of the recut nodal specimens, which altered staging in two of those cases.Conclusions: Fluorescence imaging of lymph nodes after systemic cetuximab-IRDye800CW administration demonstrated high sensitivity and was capable of identifying additional positive nodes on deep sectioning. Clin Cancer Res; 23(16); 4744-52. ©2017 AACR.

Sentinel Lymph Node Biopsy: A new approach in the management of head and neck cancers

Cervical lymph node metastasis affects the prognosis and overall survival rate of and therapeutic planning for patients with head and neck squamous cell carcinomas (HNSCCs). However, advanced diagnostic modalities still lack accuracy in detecting occult neck metastasis. A sentinel lymph node biopsy is a minimally invasive auxiliary method for assessing the presence of occult metastatic disease in a patient with a clinically negative neck. This technique increases the specificity of neck dissection and thus reduces morbidity among oral cancer patients. The removal of sentinel nodes and dissection of the levels between the primary tumour and the sentinel node or the irradiation of target nodal basins is favoured as a selective treatment approach; this technique has the potential to become the new standard of care for patients with HNSCCs. This article presents an update on clinical applications and novel developments in this field.

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.

Sentinel lymph node biopsy reduces the incidence of secondary neck metastasis in patients with oral squamous cell carcinoma

It has recently been established that sentinel node biopsy (SNB) is an applicable and feasible procedure for the prediction of neck lymph node status in patients with early oral squamous cell carcinoma (OSCC) who are clinically negative for neck metastasis (cN0). The aim of this study was to retrospectively compare excision followed by watchful waiting with excision and SNB, in order to determine the effectiveness of SNB. A total of 125 patients with cN0 early OSCC were divided into two groups, namely the excision alone (n=78) and excision with SNB (n=47) groups. The clinical data of these two groups between 2006 and 2013 were analyzed. In the excision with SNB group, the negative predictive value and false-negative rate of SNB were 94% (30/32) and 18% (2/11), respectively. Secondary neck metastasis, also known as delayed neck metastasis, occurred in 24.2% of the patients in the excision alone group and 4.9% of the patients in the excision with SNB group. The 5-year overall survival (OS) rates were 84.0 and 97.5% in the excision alone and excision with SNB groups, respectively. Significant differences were found in the rate of secondary neck metastasis and OS between the two groups. SNB may be effective in the detection of occult neck lymph node metastasis, with a reduction in the incidence of secondary neck metastasis and improvements in the 5-year OS in patients with early-stage (stage I/II) oral cancer.

Staging of early lymph node metastases with the sentinel lymph node technique and predictive factors in T1/T2 oral cavity cancer: A retrospective single-center study

BACKGROUND

The purpose of this study was to examine the diagnostic accuracy of detecting lymph node metastases and to identify predictive and prognostic clinicopathological factors in patients with oral squamous cell carcinoma (OSCC) undergoing sentinel lymph node biopsy (SLNB).

METHODS

All patients diagnosed with cT1 to T2N0 OSCC who underwent a diagnostic SLNB between 2007 and 2013 were included.

RESULTS

We identified 253 patients, of whom 27% had a positive sentinel lymph node (SLB). The false-negative rate, sensitivity, and negative predictive value (NPV) were 5%, 88%, and 95%, respectively. Patients with micrometastases as well as macrometastases had a separately, significantly shorter disease-specific survival than patients with pN0 disease. In a logistic regression model, the maximum tumor thickness, perineural invasion, and differentiation grade were independent predictive factors for the presence of metastases.

CONCLUSION

These data support the use of the SLNB technique as an accurate and safe staging tool in patients with OSCC with a cN0 neck. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1033-E1040, 2016.

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.