A model to predict nodal metastasis in patients with oral squamous cell carcinoma

Impact of histopathological parameters in prognosis of oral squamous cell carcinoma

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

A Study of Histological and Clinical Parameters and Their Correlation With Lymph Node Metastasis and Two-Year Survival in 50 Cases of Oral Squamous Cell Carcinoma

INTRODUCTION

Oral squamous cell carcinoma (OSCC) is one of the most prevalent malignant neoplasms in South Asia and a major public health problem in India. The purpose of the study was to identify correlations among various clinicopathological parameters of OSCC in a tertiary care center in the Eastern Uttar Pradesh population of North India. The study is imperative due to the scarcity of available data from this region.

METHODOLOGY

A retrospective observational study was conducted on the cases received in the Department of Pathology over the period of January 2021 to December 2021. The study analyzed cases of OSCC, focusing on various factors such as age, gender, habits, tumor site, tumor size, differentiation, tumor-stroma ratio, tumor-infiltrating lymphocytes, tumor budding, worst pattern of invasion, depth of invasion, perineural invasion, lymphovascular invasion, underlying bone and overlying skin involvement, regional lymph node metastasis, and overall two-year survival.

RESULTS

The mean age of the patients was 47.80 ± 12.48 years, and the male-to-female ratio was 15.6:1. Buccal mucosa was the most frequently affected site followed by the tongue. Fifty-six percent of cases reported with a history of tobacco abuse. Thirty-six percent of the patients had regional lymph node metastasis and exhibited a strong association with younger age, substance abuse, higher tumor size, tongue as a site, moderate-to-poor tumor differentiation, low tumor-infiltrating lymphocytes, and higher perineural and lymphovascular invasion. Moreover, at the end of the two-year survival analysis, 34% of patients succumbed to the disease. Overall survival was observed to be significantly better with <2 cm maximum tumor size, well-differentiated tumor morphology, higher tumor-infiltrating lymphocytes, and no nodal metastasis.

CONCLUSIONS

The study highlights the intricate correlations of various histopathological factors in OSCC, shedding light on their potential implications for prognosis.

Leveraging technology-driven strategies to untangle omics big data: circumventing roadblocks in clinical facets of oral cancer

Oral cancer is one of the 19most rapidly progressing cancers associated with significant mortality, owing to its extreme degree of invasiveness and aggressive inclination. The early occurrences of this cancer can be clinically deceiving leading to a poor overall survival rate. The primary concerns from a clinical perspective include delayed diagnosis, rapid disease progression, resistance to various chemotherapeutic regimens, and aggressive metastasis, which collectively pose a substantial threat to prognosis. Conventional clinical practices observed since antiquity no longer offer the best possible options to circumvent these roadblocks. The world of current cancer research has been revolutionized with the advent of state-of-the-art technology-driven strategies that offer a ray of hope in confronting said challenges by highlighting the crucial underlying molecular mechanisms and drivers. In recent years, bioinformatics and Machine Learning (ML) techniques have enhanced the possibility of early detection, evaluation of prognosis, and individualization of therapy. This review elaborates on the application of the aforesaid techniques in unraveling potential hints from omics big data to address the complexities existing in various clinical facets of oral cancer. The first section demonstrates the utilization of omics data and ML to disentangle the impediments related to diagnosis. This includes the application of technology-based strategies to optimize early detection, classification, and staging via uncovering biomarkers and molecular signatures. Furthermore, breakthrough concepts such as salivaomics-driven non-invasive biomarker discovery and omics-complemented surgical interventions are articulated in detail. In the following part, the identification of novel disease-specific targets alongside potential therapeutic agents to confront oral cancer via omics-based methodologies is presented. Additionally, a special emphasis is placed on drug resistance, precision medicine, and drug repurposing. In the final section, we discuss the research approaches oriented toward unveiling the prognostic biomarkers and constructing prediction models to capture the metastatic potential of the tumors. Overall, we intend to provide a bird's eye view of the various omics, bioinformatics, and ML approaches currently being used in oral cancer research through relevant case studies.

Utility of Elective Neck Dissection in Clinically Node-Negative Parotid Malignancy

OBJECTIVE

We sought to investigate the utility of elective neck dissection (END) in clinically node-negative parotid malignancy through the evaluation of factors that are associated with receiving END and survival analysis of patients who received END.

STUDY DESIGN

Retrospective cohort database study.

SETTING

The National Cancer Database (NCDB).

METHODS

The NCDB was used to extract patients with clinically node-negative parotid malignancy. END was defined as having 5 or more lymph nodes examined pathologically, as previously defined in the literature. Univariate and multivariate analyses were used to compare predictors of receiving END, rates of occult metastasis, and survival.

RESULTS

Of the 9405 included patients, 3396 (36.1%) underwent an END. END was most frequently performed for squamous cell carcinoma (SCC) and salivary duct histology. All other histologies were significantly less likely to undergo END compared to SCC (p < .05). Salivary ductal carcinoma and adenocarcinoma had the greatest rates of occult node disease (39.8% and 30.0%, respectively), followed by SCC (29.8%). Kaplan-Meier survival analysis showed a statistically significant increase in 5-year overall survival in patients who received END with poorly differentiated mucoepidermoid (56.2% vs 48.5%, p = .004) along with moderately and poorly differentiated SCC (43.2% vs 34.9%, p = .002; 48.9% vs 36.2%, p < .001, respectively).

CONCLUSION

Histological classification is a benchmark for determining which patients should receive an END. We demonstrated an increase in overall survival in patients who undergo END with poorly differentiated tumors of mucoepidermoid and SCC histology. As such, histology should be considered along with clinical T-stage and rate of occult nodal metastasis to determine eligibility for END.

An Oral Microbial Biomarker for Early Detection of Recurrence of Oral Squamous Cell Carcinoma

Changes in the oral microbiome are associated with oral squamous cell carcinoma (OSCC). Oral microbe-derived signatures have been utilized as markers of OSCC. However, the structure of the oral microbiome during OSCC recurrence and biomarkers for the prediction of OSCC recurrence remains unknown. To identify OSCC recurrence-associated microbial biomarkers for the prediction of OSCC recurrence, we performed 16S rRNA amplicon sequencing on 54 oral swab samples from OSCC patients. Differences in bacterial compositions were observed in patients with vs without recurrence. We found that Granulicatella, Peptostreptococcus, Campylobacter, Porphyromonas, Oribacterium, Actinomyces, Corynebacterium, Capnocytophaga, and Dialister were enriched in OSCC recurrence. Functional analysis of the oral microbiome showed altered functions associated with OSCC recurrence compared with nonrecurrence. A random forest prediction model was constructed with five microbial signatures including Leptotrichia trevisanii, Capnocytophaga sputigena, Capnocytophaga, Cardiobacterium, and Olsenella to discriminate OSCC recurrence from original OSCC (accuracy = 0.963). Moreover, we validated the prediction model in another independent cohort (46 OSCC patients), achieving an accuracy of 0.761. We compared the accuracy of the prediction of OSCC recurrence between the five microbial signatures and two clinicopathological parameters, including resection margin and lymph node counts. The results predicted by the model with five microbial signatures showed a higher accuracy than those based on the clinical outcomes from the two clinicopathological parameters. This study demonstrated the validity of using recurrence-related microbial biomarkers, a noninvasive and effective method for the prediction of OSCC recurrence. Our findings may contribute to the prognosis and treatment of OSCC recurrence.

Revisiting the Predictive Factors for Nodal Metastasis in Oral Cancers-a Leap Towards Personalized Patient Treatment Approach

The incidence of oral squamous cell carcinoma is steadily increasing globally, and even with a better understanding of tumor biology and advanced treatment modalities, the survival of OSCC patients is still not improved. A single metastatic cervical node can decrease survival by 50%. Our study intends to identify the clinical, radiological, and histological factors, significant for nodal metastasis in the pretreatment setting. Ninety-three patients' data is prospectively collected and analyzed to identify the significance of various factors in predicting nodal metastasis. Clinical factors like smokeless tobacco and nodal characteristics and T category and radiological factors like the number of specific nodes were significant for pathological nodes on univariate analysis. Ankyloglossia, radiological ENE, and radiological nodal size were significant on multivariate analysis also. In the pretreatment setting, clinicopathological and radiological factors can be used to predict nodal metastasis in generating predictive nomograms and for better planning of treatment.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Knockdown of circGOLPH3 inhibits cell progression and glycolysis by targeting miR-145-5p/lysine demethylase 2A (KDM2A) axis in oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) is one of the most common head and neck malignancies. The aim of this study is to explore the role of circRNA Golgi phosphoprotein 3 (GOLPH3) (circGOLPH3) in OSCC.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were performed to detect changes in the levels of circGOLPH3, microRNA-145-5p (miR-145-5p), and lysine demethylase 2A (KDM2A). The functions of circGOLPH3 were assessed using in vitro and in vivo assays. Dual-luciferase reporter assay detected the interaction of miR-145-5p with circGOLPH3 or KDM2A.

RESULTS

circGOLPH3 expression was upregulated in OSCC. circGOLPH3 downregulation inhibited cell growth, metastasis, and glycolysis in vitro, and in vivo experiments revealed that circGOLPH3 inhibited tumor growth. In addition, circGOLPH3 bound to miR-145-5p and competitively inhibited KDM2A expression, thereby regulating OSCC cell behaviors as well as glycolysis.

CONCLUSION

circGOLPH3 exerted pro-oncogenic effects through the miR-145-5p/KDM2A axis to regulate OSCC cell behaviors.

Prevalence of Skip Metastases to Cervical Lymph-Nodes in Oral cavity Cancer in Eastern India-an observational study

To determine the prevalence of skip metastases in Oral-squamous-cell-carcinoma (OSCC). This prospective observational study was carried out on 100-cases of biopsy proven OSCC who underwent surgical treatment for the primary tumor along with neck dissection (ND). Data regarding depth of invasion (DOI) by primary tumor, perineural-invasion, lymphovascular-invasion, presence of metastatic-lymph-node (level, size, number and extranodal-extension) were collected from histopathology reports and were analyzed. Out of 100-cases, 73-were-male and 27-were-female. Mean age was 49.5 ± 12.3 years (range 24-4 years). Common subsites of tumor were buccal-mucosa, tongue and lower-alveolus in 40, 37 and 14% respectively. Pathological staging of tumor were stage-I, stage-II, stage-III, stage-IVa and stage-IVb in 22, 14, 25, 22 and 15% cases respectively. Preoperative neck staging was cN0 in 50 necks (47.2%) and cN+ in 56 necks (52.8%). In 100-patients 106-NDs (unilateral-94 and bilateral-6) were performed. Type of NDs were Supraomohyoid, extended-Supraomohyoid and modified radical neck-dissection in 23,07and76 cases respectively. Prevalence of cervical lymph node metastases was 36% (pN + necks). Among 36pN + patients; 25 (69.4%) cases, 20 (55.5%) cases, 9 (25%) cases, 4 (11.1%) cases, 2 (5.5%) cases had metastases to level-I, II, III, IV and V respectively. Skip-metastases was present in four-cases {level-IIb:one-case (2.78%), level-III: two-cases (5.5%) and level-V:one-case (2.78%)}. No-skip-metastasis to level-IV was noticed. All-four-cases of skip-metastases were from advance cases of squamous-cell-carcinoma of tongue with DOI > 5 mm. Skip-metastases to levels IIb, IV and V are uncommon in cases of OSCC. Most of the metastasis in our study was noted to levels I, II and III in a predictable fashion. Thus, extensive ND can be avoided in patients to prevent complications and morbidities associated with the same.

Sentinel node biopsy in node negative early oral cancers: Solution to the conundrum!

Ideal management of the node-negative neck in early oral cancers is a debated issue. Elective neck dissection (END) is recommended in these patients as it offers a survival benefit. However, about 50-70% of patients who do not harbor occult metastasis are overtreated with this approach. Surgery is associated with morbidity, predominantly shoulder dysfunction. Numerous attempts have been made to identify true node-negative patients through imaging and prediction models but none have high diagnostic accuracy to safely spare the neck dissection. The recent publications of 2 large randomized controlled trials comparing the outcomes of sentinel node biopsy (SNB) and END have spurred interest in SNB. Both the trials reported SNB to be an oncologically safe procedure and spared unnecessary neck dissections. The functional outcomes of the trials showed that SNB limits the morbidity compared to END, which albeit evens out at the end of one-year post-surgery. Despite its benefits, SNB has failed to gain widespread acceptability due to various limitations including the need for infrastructure, equipment costs, staff, and multidisciplinary collaboration of nuclear medicine, surgical, and pathology fraternity. The labor-intensive pathology protocol with serial step sectioning and immunohistochemistry poses a challenge to the feasibility at a high-volume center. This perspective discusses these limitations and propose plausible solutions to the conundrum. To make it widely applicable and feasible across the globe efforts should be directed to understand biology better, find novel solutions, and implement the lessons learned over decades from other sites.

Dissecting Tissue Compartment-Specific Protein Signatures in Primary and Metastatic Oropharyngeal Squamous Cell Carcinomas

Head and neck squamous cell carcinoma (HNSCC) often presents with locoregional or distant disease, despite multimodal therapeutic approaches, which include surgical resection, chemoradiotherapy, and more recently, immunotherapy for metastatic or recurrent HNSCC. Therapies often target the primary and nodal regional HNSCC sites, and their efficacy at controlling occult distant sites remains poor. While our understanding of the tumor microenvironment conducive to effective therapies is increasing, the biology underpinning locoregional sites remains unclear. Here, we applied targeted spatial proteomic approaches to primary and lymph node metastasis from an oropharyngeal SCC (OPSCC) cohort to understand the expression of proteins within tumors, and stromal compartments of the respective sites in samples of both matched and unmatched patients. In unmatched analyses of n = 43 primary and 11 nodal metastases, our data indicated that tumor cells in nodal metastases had higher levels of Ki-67, PARP, BAD, and cleaved caspase 9, suggesting a role for increased proliferation, DNA repair, and apoptosis within these metastatic cells. Conversely, in matched analyses (n = 7), pro-apoptotic markers BIM and BAD were enriched in the stroma of primary tumors. Univariate, overall survival (OS) analysis indicated CD25 in tumor regions of primary tumors to be associated with reduced survival (HR = 3.3, p = 0.003), while progesterone receptor (PR) was associated with an improved OS (HR = 0.33, p = 0.015). This study highlights the utility of spatial proteomics for delineating the tumor and stromal compartment composition, and utility toward understanding these properties in locoregional metastasis. These findings indicate unique biological properties of lymph node metastases that may elucidate further understanding of distant metastatic in OPSCC.

A validated predictive model for risk of nodal metastasis in node negative oral squamous cell carcinoma of the buccal mucosa and tongue

BACKGROUND

Lymph node metastasis in oral squamous cell carcinoma (OSCC) is influenced by clinical and histopathological variables. The aim of this study was to develop a simple model to predict nodal metastasis of OSCC in clinically negative necks (cN0).

METHODS

Data from patients who underwent surgery for treatment of OSCC of the tongue or buccal mucosa with neck dissection were used for model development and validation.

RESULTS

Nodal metastasis was significantly associated with gender, age, tumor size, site, pattern of invasion and depth of invasion on univariate analysis. All the five variables except age were retained at the variable selection step of the model development and were used in the final model because it was not significant at 0.10 significance level after adjusting for other variables. Regression coefficients of the model were used to estimate risks of nodal metastases for each combination of clinicopathological characteristics. A 10-fold cross-validation was used to assess the model. The average of the resultant 10 AUCs (along with its 95% confidence interval estimated using bootstrap) was used as the overall validated measure of the model. A risk chart was produced using probability of nodal metastasis predicted by the model for each combination of five characteristics. The model's ability to identify patients with nodal metastases as assessed by the area under the ROC curve (AUC) was 0.752.

CONCLUSION

The model based on established clinicopathological variables has been internally validated on a large cohort of patients and offers practicability for use in OSCCs of the tongue and buccal mucosa.

Machine Learning Algorithms as a Computer-Assisted Decision Tool for Oral Cancer Prognosis and Management Decisions: A Systematic Review

INTRODUCTION

Despite multiple prognostic indicators described for oral cavity squamous cell carcinoma (OCSCC), its management still continues to be a matter of debate. Machine learning is a subset of artificial intelligence that enables computers to learn from historical data, gather insights, and make predictions about new data using the model learned. Therefore, it can be a potential tool in the field of head and neck cancer.

METHODS

We conducted a systematic review.

RESULTS

A total of 81 manuscripts were revised, and 46 studies met the inclusion criteria. Of these, 38 were excluded for the following reasons: use of a classical statistical method (N = 16), nonspecific for OCSCC (N = 15), and not being related to OCSCC survival (N = 7). In total, 8 studies were included in the final analysis.

CONCLUSIONS

ML has the potential to significantly advance research in the field of OCSCC. Advantages are related to the use and training of ML models because of their capability to continue training continuously when more data become available. Future ML research will allow us to improve and democratize the application of algorithms to improve the prediction of cancer prognosis and its management worldwide.

LncRNA NORAD facilitates oral squamous cell carcinoma progression by sponging miR-577 to enhance TPM4

BACKGROUND

Long non-coding RNAs (lncRNAs) have been reported to be vital factors to affect the expression of genes and proteins. Also, it has been proved that the abnormal expression or mutation of lncRNAs stands as a signal of metastasis and proliferation of cancer. Nevertheless, the majority of lncRNAs still need to be explored in abundant cancers especially in oral squamous cell carcinoma (OSCC).

METHODS

RT-qPCR assays were applied to test the expression of RNAs. Mechanism assays were performed to verify the combination among NORAD, TPM4 and miR-577. Also, functional assays were conducted to verify the function of RNAs on OSCC cells.

RESULTS

LncRNA NORAD was highly expressed in OSCC tissues and cells. NORAD silencing repressed the biological behaviors of OSCC cells. MiR-577 was found in OSCC with low expression, and RIP assays illustrated that NORAD, miR-577 and TPM4 coexisted in RNA-induced silencing complexes. Rescue assays proved that the overexpression of TPM4 could recover the effect of NORAD silencing on OSCC progression.

CONCLUSIONS

It was revealed that NORAD functioned as a tumor promoter to sponge miR-577 thus elevating TPM4 in OSCC, which indicated that NORAD was worthy to be studied as a target for the treatment of OSCC.

Importance and implications of neurovascular bundle involvement and other MRI findings of oral tongue squamous cell carcinoma (OTSCC) on prognosis

BACKGROUND

The description for T4a oral tongue cancer in the 8th edition AJCC staging can be improved further. In this article we attempted to identify the important radiological (MRI) findings that could possibly be included in the staging eventually.

METHODS

We included all oral tongue squamous cell carcinoma patients who underwent surgery at TMH between Jan 2012 to Dec 2018 and whose MRIs were available for review. The relation of the tumor to the neurovascular bundle (NVB) on MRI was classified as Type I to IV. The association of the type of NVB involvement with DFS and the presence of PNI in the final HPR was analyzed.

RESULTS

Two-hundred and fifty-nine patients satisfied the eligibility criteria. The majority of them were men (82.6%), with a median age of 49 Yrs. Sixty-nine percent of patients had either abutment (Type III) or encasement (Type IV) of the NVB. The presence of Abutment/encasement of the NVB was significantly associated with the presence of PNI in the final HPR (p < 0.001). This abutment/encasement was seen in clinically advanced T-stage tumors. However, the presence of abutment/encasement of the NVB influenced the DFS in the univariate analysis only.

CONCLUSION

Abutment/encasement of the NVB in patients with carcinoma oral tongue is often seen in advanced-stage tumors and is significantly associated with the presence of PNI in the final HPR. Hence, the relation of the tumor with the NVB should be further assessed to understand its importance and its possible inclusion in the AJCC T-staging.

Circ_0000745 strengthens the expression of CCND1 by functioning as miR-488 sponge and interacting with HuR binding protein to facilitate the development of oral squamous cell carcinoma

BACKGROUND

The implication of circular RNAs (circRNAs) in human cancers has aroused much concern. In this study, we investigated the function of circ_0000745 and its potential functional mechanisms in oral squamous cell carcinoma (OSCC) to further understand OSCC pathogenesis.

METHODS

The expression of circ_0000745, miR-488 and cyclin D1 (CCND1) mRNA was measured by quantitative real-time polymerase chain reaction (qPCR). Cell proliferation capacity was assessed by cell counting kit-8 (CCK-8) assay and colony formation assay. Cell cycle progression and cell apoptosis were determined by flow cytometry assay. The protein levels of CCND1, PCNA, Cleaved-caspase 3 and HuR were detected by western blot. Animal study was conducted to identify the role of circ_0000745 in vivo. The targeted relationship was verified by dual-luciferase reporter assay, pull-down assay or RNA immunoprecipitation (RIP) assay.

RESULTS

The expression of circ_0000745 was increased in OSCC tissues and cells. Circ_0000745 downregulation inhibited OSCC cell proliferation and induced cell cycle arrest and apoptosis in vitro, as well as blocked tumor growth in vivo. MiR-488 was a target of circ_0000745, and circ_0000745 downregulation suppressed OSCC development by enriching miR-488. Besides, circ_0000745 regulated CCND1 expression by targeting miR-488. In addition, circ_0000745 regulated CCND1 expression by interacting with HuR protein. CCND1 knockdown also inhibited OSCC cell proliferation and induced cell cycle arrest and apoptosis in vitro, and CCND1 overexpression recovered the inhibitory effects on OSCC cell malignant behaviors caused by circ_0000745 downregulation.

CONCLUSIONS

Circ_0000745 regulated the expression of CCND1 partly by acting as miR-488 sponge and interacting with HuR protein, thus promoting the progression of OSCC.

Impact of tumor site on the prognosis of salivary gland neoplasms: A systematic review and meta-analysis

In numerous types of cancer, the primary tumor site can show a correlation with disease behavior and survival outcomes. In salivary gland tumors (SGTs) this association remains controversial. This study assessed the association between primary sites of SGTs and prognosis. Studies from five databases were assessed and a meta-analysis was performed using studies that presented 95 % confidence interval (95 % CI), hazard ratio (HR) and survival analysis. Gathered information from 46,361 patients showed that site had a prognostic impact on SGTs. Tumors involving minor salivary glands showed worse overall survival (HR = 1.60; 95 % CI = 1.17-2.19; p = 0.003), disease-specific survival (HR=1.63; 95 % CI = 1.12-2.37; p = 0.01), and cause-specific survival (HR=2.10; 95 % CI = 1.72-2.55; p = 0.00001). Tumors from major salivary glands showed better recurrence-free survival (HR=2.31; 95 % CI = 1.77-3.02; p = 0.00001), and locoregional control of disease (HR=2.66; 95 % CI = 1.20-5.91; p = 0.02). Our results showed that the primary site of SGTs has an impact on patient prognosis.

Contralateral Regional Recurrence in Lateralized or Paramedian Early-Stage Oral Cancer Undergoing Sentinel Lymph Node Biopsy-Comparison to a Historic Elective Neck Dissection Cohort

Introduction: Nowadays, two strategies are available for the management of the clinically negative neck in early-stage (cT1-2N0) oral squamous cell carcinoma (OSCC): elective neck dissection (END) and sentinel lymph node biopsy (SLNB). SLNB stages both the ipsilateral and the contralateral neck in early-stage OSCC patients, whereas the contralateral neck is generally not addressed by END in early-stage OSCC not involving the midline. This study compares both incidence and hazard of contralateral regional recurrences (CRR) in those patients who underwent END or SLNB.

Materials and Methods: A retrospective multicenter cohort study, including 816 lateralized or paramedian early-stage OSCC patients, staged by either unilateral or bilateral END (n = 365) or SLNB (n = 451).

Results: The overall rate of occult contralateral nodal metastasis was 3.7% (30/816); the incidence of CRR was 2.5% (20/816). Patients who underwent END developed CRR during follow-up more often than those who underwent SLNB (3.8 vs. 1.3%; p = 0.018). Moreover, END patients had a higher hazard for developing CRR than SLNB patients (HR = 2.585; p = 0.030). In addition, tumor depth of invasion was predictive for developing CRR (HR = 1.922; p = 0.009). Five-year disease-specific survival in patients with CRR was poor (42%) compared to patients in whom occult contralateral nodal metastases were detected by SLNB or bilateral END (88%), although not statistically different (p = 0.066).

Conclusion: Our data suggest that SLNB allows for better control of the contralateral clinically negative neck in patients with lateralized or paramedian early-stage OSCC, compared to END as performed in a clinical setting. The prognosis of those in whom occult contralateral nodal metastases are detected at an earlier stage may be favorable compared to those who eventually develop CRR, which highlights the importance of adequate staging of the contralateral clinically negative neck.

Clinicopathological and immunohistochemical characteristics of pigmented oral squamous cell carcinoma

Pigmented oral squamous cell carcinoma (POSCC) is a rare and underrecognized pathological variant of oral squamous cell carcinoma (OSCC). The current study aimed to evaluate the clinicopathological characteristics, treatment outcomes and prognosis of patients with POSCC and to investigate its oncological properties using immunohistochemical studies. A total of 1,512 patients were pathologically diagnosed with squamous cell carcinoma of the oral cavity, and were treated at the Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University between January 2001 and December 2018. A total of 25 patients had POSCC and underwent radical surgery. Of these 25 patients, 23 presented with early T stage disease. Additionally, 22 patients were negative for cervical lymph nodes metastasis. Only one patient had local recurrence. The 5-year disease-free and disease-specific survival rates were 86.6 and 95.8%, respectively. Immunohistochemically, a high percentage of POSCC exhibited low p53 and Ki-67, preserved E-cadherin or negative vimentin expression. The results suggested that POSCC tends to exhibit non-aggressive oncological behavior and demonstrates a good prognosis.

Impact of Histological and Molecular Parameters on Prognosis of Oral Squamous Cell Carcinoma: Analysis of 290 Cases

Background

Nodal metastasis is a critical factor in predicting the prognosis of oral squamous cell carcinoma (OSCC). When patients present with a clinically positive neck, the treatment of choice is radical neck dissection. However, management of a clinically negative neck is still a subject of significant controversy.

Aim

This study was carried out in order to propose a model to predict regional lymph node metastasis of OSCC using histological parameters such as tumour stage, tumour size, pattern of invasion (POI), differentiation of tumour, and host immune response, together with the expression levels of six biomarkers (periostin, HIF-1α, MMP-9, β-catenin, VEGF-C, and EGFR), and, furthermore, to compare the impact of all these parameters on recurrence and 3 yr and 5 yr survival rates. Materials and Method. Histological materials collected from the archives were used to evaluate histological parameters and immunohistochemical profiles. Standard methods were used for immunohistochemistry and for evaluation of results. Data related to recurrence and survival (3 and 5 years) was also recorded. Clinical data was collected from patients' records.

Results

Male to female ratio was 3 : 1. The commonest site of OSCC was the buccal mucosa, and majority of them were T3 or T4 tumours presented at stage 4. 62.5% of the tumours were well differentiated. Three-year and 5-year survival rates were significantly associated with lymph node metastasis and recurrence. POI was significantly correlated with tumour size, stage, 3-year survival, EGFR, HIF-1α, periostin, and MMP-9 (p < 0.05). Expression of EGFR showed a direct association with metastasis (p < 0.05).

Conclusion

POI, level of differentiation, and expression of EGFR are independent prognostic markers for lymph node metastasis. Therefore, these parameters may help in treatment planning of a clinically negative neck.

Tumor histologic grade as a risk factor for neck recurrence in patients with T1-2N0 early tongue cancer

OBJECTIVES

In current guidelines, early tongue cancer status post partial glossectomy without adverse risk features do not require adjuvant treatment. However, many of these patients developed recurrence with neck metastases soon. The objectives of this study were to investigate the potential risk factors in early tongue cancer that prophylactic management of neck may be considered.

MATERIALS AND METHODS

From January 2010 to September 2015, this retrospective study enrolled 102 patients with T1-2N0 primary oral tongue squamous cell carcinoma according to AJCC 8th edition Cancer Staging System. All patients underwent partial glossectomy with or without selective neck dissection, and did not receive any adjuvant treatment. Patients with any adverse risk features were excluded. We have studied the 4-year cancer-specific survival and neck recurrence rate, and analyzed the relevance between pathologic tumor classification, tumor depth, tumor histologic grade, and measured surgical margin of primary tumor.

RESULTS

The median follow up duration was 47 months (range 6-93 months) with the median recurrence interval was 13 months. Histologic grade ≥2 of primary tumor was significantly associated with increased risk of neck recurrence and disease-specific mortality in both univariate and multivariate analysis.

CONCLUSION

Histologic grade ≥2 was an adverse prognostic factor of neck recurrence and was significantly associated with poor cancer-specific survival in T1-2N0 early oral tongue cancer patients. Therefore, prophylactic neck dissection or prophylactic adjuvant radiation therapy to neck may be considered in T1-2N0 early oral tongue cancer with histologic grade ≥2 of primary tumor.

Association between immunohistochemical expression of matrix metalloproteinases and metastasis in oral squamous cell carcinoma: Systematic review and meta-analysis

BACKGROUND

The aim of this systematic review (SR) was to summarize and critically appraise available evidence on the association of the immunohistochemical expression of matrix metalloproteinases (MMPs) with the occurrence of lymph node/distant metastasis of oral squamous cell carcinoma (OSCC).

METHODS

Searches were conducted in five main electronic and three gray literature databases.

RESULTS

From 2128 records identified, 50 were included for qualitative analysis. A total of 12 MMPs were identified (-1, -2, -3, -7, -8, -9, -10, -11, -13, -25, -26, and MT1-MMP). Most included studies reported a positive association of MMP-1, -2, -3, -7, -9, and MT1-MMP with lymph node metastasis. MMP-8, -25, and -26 were not associated with lymph node metastasis.

CONCLUSIONS

According to this SR, MMP-1, -2, -3, -7, -9, and MT1-MMP seem to play an important role in lymph node metastasis of OSCC.

Immunohistochemical quantification of partial-EMT in oral cavity squamous cell carcinoma primary tumors is associated with nodal metastasis

OBJECTIVES

Quantify by immunohistochemistry (IHC) a partial epithelial-to-mesenchymal transition (p-EMT) population in oral cavity squamous cell carcinoma (OCSCC) and determine its predictive value for lymph node metastasis.

METHODS

Tissue microarrays (TMA) were created using 2 mm cores from 99 OCSCC patients (47 with low volume T2 disease, 52 with high volume T4 disease, and ∼50% in each group with nodal metastasis). IHC staining was performed for three validated p-EMT markers (PDPN, LAMB3, LAMC2) and one marker of well-differentiated epithelial cells (SPRR1B). Staining was quantified in a blinded manner by two reviewers. Tumors were classified as malignant basal subtype based on staining for the four markers. In this subset, the p-EMT score was computed as the average of p-EMT markers.

RESULTS

84 tumors were classified as malignant basal. There was 87% inter-rater consistency in marker quantification. There were associations of p-EMT scores with higher grade (2.15 vs. 1.92, p = 0.04), PNI (2.13 vs. 1.83, p = 0.003), and node positivity (2.09 vs. 1.87, p = 0.02), including occult node positivity (56% vs. 19%, p = 0.005). P-EMT was independently associated with nodal metastasis in a multivariate analysis (OR 3.12, p = 0.039). Overall and disease free survival showed trends towards being diminished in the p-EMT high group.

CONCLUSIONS

IHC quantification of p-EMT in OCSCC primary tumors is reliably associated with nodal metastasis, PNI, and high grade. With prospective validation, p-EMT biomarkers may aid in decision-making over whether to perform a neck dissection in the N0 neck and/or for adjuvant therapy planning.

Sandensolide Induces Oxidative Stress-Mediated Apoptosis in Oral Cancer Cells and in Zebrafish Xenograft Model

Presently, natural sources and herbs are being sought for the treatment of human oral squamous cell carcinoma (OSCC) in order to alleviate the side effects of chemotherapy. This study investigates the effect of sandensolide, a cembrane isolated from Sinularia flexibilis, to inhibit human OSCC cell growth with the aim of developing a new drug for the treatment of oral cancer. In vitro cultured human OSCC models (Ca9.22, SCC9 and HSC-3 cell lines) and oral normal cells (HGF-1), as well as a zebrafish xenograft model, were used to test the cytotoxicity of sandensolide (MTT assay), as well as to perform cell cycle analysis and Western blotting. Both the in vitro bioassay and the zebrafish xenograft model demonstrated the anti-oral cancer effect of sandensolide. Moreover, sandensolide was able to significantly suppress colony formation and induce apoptosis, as well as cell cycle arrest, in OSCC by regulating multiple key proteins. Induction of reactive oxygen species (ROS) was observed in sandensolide-treated oral cancer cells. However, these apoptotic changes were rescued by NAC pretreatment. These findings contribute to the knowledge of the model of action of sandensolide, which may induce oxidative stress-mediated cell death pathways as a potential agent in oral cancer therapeutics.