Pattern and localization of perineural invasion predict poor survival in oral tongue carcinoma

Pretreatment Pain as a Prognostic Predictor in Oral Tongue Squamous Cell Carcinoma: The Mediating Role of Perineural Invasion

BACKGROUND

The potential effects of pretreatment pain on prognosis of tongue squamous cell carcinoma (TSCC) and the role that perineural invasion (PNI) plays in this process remains unclear.

PURPOSE

The purposes of this study are to estimate the prognostic value of pretreatment pain and identify whether PNI is a mediating factor in the relationship between pretreatment pain and prognosis in TSCC.

STUDY DESIGN, SETTING, SAMPLE

This retrospective cohort study included TSCC patients who underwent first resections of primary lesions at the Beijing Stomatological Hospital of Capital Medical University between January 2009 and December 2019. Patients who had incomplete medical records and pathological data, received neoadjuvant radiotherapy and chemotherapy before surgery, and did not receive a TSCC diagnosis, were excluded.

PREDICTOR VARIABLE

The predictor variables are pretreatment pain and PNI. The visual analog scale (VAS) was used to assess pretreatment pain levels, and the PNI status was evaluated by pathological section.

MAIN OUTCOME VARIABLE(S)

The main outcome variables were the 3-year disease-specific survival (DSS) and disease-free survival (DFS).

COVARIATES

Covariates included age, sex, smoking history, alcohol history, growth pattern, and T-stage.

ANALYSES

The χ2 test was used to describe the baseline data. Kaplan-Meier analysis was used to estimate the 3-year DSS and DFS. The Cox regression model was adapted for univariate and multivariate analysis. The association between VAS score and PNI was analyzed using logistic regression analysis and mediation analysis. P value less than .05 indicated statistical significance.

RESULTS

The study included 307 subjects with a mean age of 52 (±12.1) years, and 164 (53.4%) were male. There were 65 (21.2%) with high VAS (>5) and 242 (78.8%) with low VAS (≤5). The DSS and DFS of high VAS were 64.6% (95% CI: 23.6 to 80.9%) and 52.3% (95% CI: 35.3 to 92.8%), of patients with PNI were 62.7% (95% CI: 19.6 to 64.5%) and 46.7% (95% CI: 25.9 to 66.9%), respectively. The group high VAS/with PNI had lower DSS and DFS than group high VAS/without PNI (55.3 and 40.4% vs 88.9 and 83.3%). The VAS and PNI were identified as independent factors associated with prognosis (P < .05). Mediation analysis revealed that the indirect effect of VAS on DFS was 0.071 (95% CI: 0.011 to 0.135, P = .024), while the total effect was 0.187 (95% CI: 0.074 to 0.296, P < .001), VAS score affected the DFS of TSCC through the mediating effect of PNI.

CONCLUSION AND RELEVANCE

Our findings confirmed that pretreatment pain is associated with worse outcomes in TSCC. Patients with TSCC and severe pretreatment pain are more likely to be diagnosed with PNI, which results in a worse prognosis.

Understanding the role of nerves in head and neck cancers - a review

Worldwide, head and neck cancers (HNCs) account for approximately 900,000 cases and 500,000 deaths annually, with their incidence continuing to rise. Carcinogenesis is a complex, multidimensional molecular process leading to cancer development, and in recent years, the role of nerves in the pathogenesis of various malignancies has been increasingly recognized. Thanks to the abundant innervation of the head and neck region, peripheral nervous system has gained considerable interest for its possible role in the development and progression of HNCs. Intratumoral parasympathetic, sympathetic, and sensory nerve fibers are emerging as key players and potential targets for novel anti-cancer and pain-relieving medications in different tumors, including HNCs. This review explores nerve-cancer interactions, including perineural invasion (PNI), cancer-related axonogenesis, neurogenesis, and nerve reprogramming, with an emphasis on their molecular mechanisms, mediators and clinical implications. PNI, an adverse histopathologic feature, has been widely investigated in HNCs. However, its prognostic value remains debated due to inconsistent results when classified dichotomously (present/absent). Emerging evidence suggests that quantitative and qualitative descriptions of PNI may better reflect its clinical usefulness. The review also examines therapies targeting nerve-cancer crosstalk and highlights the influence of HPV status on tumor innervation. By synthesizing current knowledge, challenges, and future perspectives, this review offers insights into the molecular basis of nerve involvement in HNCs and the potential for novel therapeutic approaches.

Accumulating evidence from meta-analyses of prognostic studies on oral cancer: towards biomarker-driven patient selection

BACKGROUND

Many histopathologic prognostic markers, identified by routine hematoxylin and eosin (HE) staining, have been proposed for predicting the survival of patients with oral squamous cell carcinoma (OSCC). Subsequently, several meta-analyses have been conducted on these prognostic markers. We sought to analyze the accumulated evidence from these meta-analyses.

METHODS

An electronic database search of PubMed, Scopus, Ovid Medline, Web of Science, and Cochrane Library was conducted to retrieve all meta-analysis articles published on histopathologic prognostic markers of OSCC. The risk of bias of the included studies was analyzed using the Risk of Bias in Systematic Reviews (ROBIS) tool. The synthesis of the results was conducted following the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

RESULTS

There were 16 meta-analysis articles published on the histological prognostic markers of OSSC. The accumulated evidence from these meta-analyses highlighted the powerful prognostic value of depth of invasion, tumor thickness, perineural invasion, lymphovascular invasion, worst pattern of invasion, tumor budding, and tumor-stroma ratio. The highest odds ratio (OR) of a relationship between a histopathologic prognostic marker and outcome was for the depth of invasion (OR 10.16, 95% CI 5.05-20.46) and tumor thickness (OR 7.32, 95% CI 5.3-10.1) in predicting lymph node metastasis.

CONCLUSION

The published meta-analyses present robust evidence on the significance of emerging histopathologic markers, namely, worst pattern of invasion, tumor budding, and tumor-stroma ratio. It is time to consider such markers in daily pathology reporting and risk stratification of OSCC.

Smac/DIABLO protein acts as an independent prognostic factor in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) poses significant health risks with increasing incidence and mortality rates. In this context, there is an urgent need to explore novel biomarkers to enhance therapeutic strategies and improve survival. Understanding apoptotic evasion in cancer pathogenesis, this pioneering study aims to investigate the correlation between a pro-apoptotic protein Smac/DIABLO and patient prognosis within the OSCC cohort. Immunohistochemistry (IHC) was employed to analyze Smac/DIABLO protein expression and correlate with clinicopathological and prognostic factors during a long-term follow-up. Smac/DIABLO low expression was associated with worse overall survival (OS), relapse-free survival (RFS), disease-specific survival (DSS), and an increase in risk of lymph node metastasis (LNM) in univariate analyses. Furthermore, multivariate analyses confirmed Smac/DIABLO as an independent prognostic factor, predicting poorer OS [Hazard Ratio (HR) = 3.6 (95% CI 1.7-7.6), p < 0.001], RFS [HR = 2.9 (95% CI 1.4-5.6), p = 0.003], DSS [HR = 6.7 (95% CI 2.7-16.7), p < 0.001], and increased likelihood of LNM [Odds Ratio (OR) = 4.8 (95% CI 1.4-15.9), p = 0.011]. Patients with positive Smac/DIABLO expression exhibited three times higher survival probability. Low proapoptotic protein Smac/DIABLO expression significantly influences prognostic predictions and strongly correlates with poor OSCC outcomes. Future studies involving Smac-mimetic drugs in OSCC are needed to evaluate their pro-apoptotic potential in cancer cells.

Ferroptosis and oral squamous cell carcinoma: connecting the dots to move forward

Oral squamous cell carcinoma (OSCC) is an aggressive disease whose incomplete biological comprehension contributes to the inappropriate clinical management and poor prognosis. Thus, the identification of new promising molecular targets to treat OSCC is of paramount importance. Ferroptosis is a regulated cell death caused by the iron-dependent accumulation of reactive oxygen species and the consequent oxidative damage of lipid membranes. Over the last five years, a growing number of studies has reported that OSCC is sensitive to ferroptosis induction and that ferroptosis inducers exert a remarkable antitumor effect in OSCC, even in those displaying low response to common approaches, such as chemotherapy and radiotherapy. In addition, as ferroptosis is considered an immunogenic cell death, it may modulate the immune response against OSCC. In this review, we summarize the so far identified ferroptosis regulatory mechanisms and prognostic models based on ferroptosis-related genes in OSCC. In addition, we discuss the perspective of inducing ferroptosis as a novel strategy to directly treat OSCC or, alternatively, to improve sensitivity to other approaches. Finally, we integrate data emerging from the research studies, reviewed here, through in silico analysis and we provide a novel personal perspective on the potential interconnection between ferroptosis and autophagy in OSCC.

Comprehensive survival analysis of oral squamous cell carcinoma patients undergoing initial radical surgery

OBJECTIVE

This study was designed to evaluate the five-year overall survival (OS) rate and postoperative survival time of patients diagnosed with oral squamous cell carcinoma (OSCC), as well as examine the clinical and pathological factors influencing survival outcomes in OSCC patients.

METHODS

Data were collected from OSCC patients who underwent their first radical surgical intervention in the Department of Maxillofacial Surgery at the First Affiliated Hospital of Chongqing Medical University between April 2014 and December 2016. Follow-up was conducted until March 2022.

RESULTS

The study included a total of 162 patients. The observed 5-year OS rate was 59.3%. Approximately 45.7% of OSCC patients experienced postoperative recurrence or metastasis, with a 5-year overall disease-free survival rate of 49.4%. There was no significant difference in the impact of sex, age, smoking, alcohol consumption, primary tumour location, depth of invasion or primary tumour size on the 5-year survival rate (p > 0.05). Univariate analysis revealed that clinical stage (Hazard Ratio = 2.239, p = 0.004), perineural invasion (PNI) (Hazard Ratio = 1.712, p = 0.03), lymph node metastasis (pN) (Hazard Ratio = 2.119, p = 0.002), pathological differentiation (Hazard Ratio = 2.715, p < 0.001), and recurrence or metastasis (Hazard Ratio = 10.02, p < 0.001) were significant factors influencing survival. Multivariate analysis further indicated that pathological differentiation (Hazard Ratio = 2.291, p = 0.001), PNI (Hazard Ratio = 1.765, p = 0.031) and recurrence or metastasis (Hazard Ratio = 9.256, p < 0.001) were independent risk factors of survival. Intriguingly, 11 OSCC patients were diagnosed with oesophageal squamous cell carcinoma (ESCC) within 1-4 years following surgery.

CONCLUSION

The survival prognosis of OSCC patients is significantly associated with clinical stage, PNI, lymph node metastasis, pathological differentiation, and recurrence or metastasis. Pathological differentiation, PNI and recurrence or metastasis are independent risk factors affecting survival. Routine clinical screening for ESCC may be recommended for OSCC patients with a history of alcohol consumption and tobacco use.

The Prognostic Role of Perineural Invasion for Survival in Head and Neck Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

The aim of this study was to conduct a comprehensive review of the predictive significance of PNI in HNSCC survival outcomes. A systematic search was conducted across multiple databases, and all studies published in the last decade were screened (Research Registry ID: reviewregistry1853). The included studies were assessed using the Quality in Prognosis Studies tool. Survival outcome data were extracted, combined, and presented as hazard ratios (HR) with a 95% confidence interval (CI). Totally, 74 studies encompassing 27,559 patients were analyzed and revealed a cumulative occurrent rate of 30% for PNI in HNSCC. PNI+ HNSCC patients had a worse overall survival (HR: 1.91, 95% CI: 1.71-2.13), disease-specific survival (HR: 1.79, 95% CI: 1.55-2.07), disease-free survival (HR: 1.82, 95% CI: 1.69-1.96), local recurrence (HR: 2.54, 95% CI: 1.93-3.33), locoregional recurrence (HR: 2.27, 95% CI: 1.82-2.82), locoregional relapse free survival (HR: 1.77, 95% CI: 1.28-2.45), distant metastasis (HR: 1.82, 95% CI: 1.34-2.48), and distant metastasis-free survival (HR: 2.97, 95% CI: 1.82-4.85) compared to those PNI- patients. The available evidence unequivocally establishes PNI as a critical prognostic factor for worse survival in HNSCC patients.

Nerve-tumor crosstalk in tumor microenvironment: From tumor initiation and progression to clinical implications

The autonomic nerve system (ANS) innervates organs and tissues throughout the body and maintains functional balance among various systems. Further investigations have shown that excessive activation of ANS not only causes disruption of homeostasis, but also may promote tumor formation. In addition, the dynamic interaction between nerve and tumor cells in the tumor microenvironment also regulate tumor progression. On the one hand, nerves are passively invaded by tumor cells, that is, perineural invasion (PNI). On the other hand, compared with normal tissues, tumor tissues are subject to more abundant innervation, and nerves can influence tumor progression through regulating tumor proliferation, metastasis and drug resistance. A large number of studies have shown that nerve-tumor crosstalk, including PNI and innervation, is closely related to the prognosis of patients, and contributes to the formation of cancer pain, which significantly deteriorates the quality of life for patients. These findings suggest that nerve-tumor crosstalk represents a potential target for anti-tumor therapies and the management of cancer pain in the future. In this review, we systematically describe the mechanism by which nerve-tumor crosstalk regulates tumorigenesis and progression.

State of art of micronuclei assay in exfoliative cytology as a clinical biomarker of genetic damage in oral carcinogenesis: A systematic review and meta-analysis

Oral squamous cell carcinoma (OSCC) is the most common oral malignancy, often preceded by oral potentially malignant disorders (OPMDs). Currently, no clinical biomarker exists to predict malignancy, necessitating OPMD follow-up. Habits and environmental factors, such as smoking, and alcohol consumption, influence OSCC onset. Increased micronuclei (MNs) formation has been observed in the development of OSCC. Non-invasive diagnostic tests like exfoliative cytology offer painless and regular monitoring options. This study evaluates the impact of tobacco, alcohol, and pesticide exposure on MNs occurrence in exfoliative cytology-collected oral mucosal cells, assessing their potential as non-invasive biomarker for OSCC development prediction and monitoring in high-risk patients. Despite results from this meta-analysis supporting the existence of a stepwise increase from controls to patients with OPMD to OSCC, the translation of these findings into clinical practice is limited due to intra- and inter-individual heterogeneity, as well as methodological variability in MNs quantification. Various factors contribute to this heterogeneity, including demographic variables, methodological variability of different laboratories, staining techniques, sample collection location, and patient characteristics. All these points were discussed to provide further insights and improve standardization for future studies.

High-risk TP53 mutations predict poor primary treatment response of patients with head and neck squamous cell carcinoma

OBJECTIVES

Head and neck squamous cell carcinoma (HNSCC) poses a diagnostic and therapeutic challenge worldwide and is associated with a poor survival rate. Due to the variability in the efficacy of treatments for HNSCC, new predictive biomarkers of therapy outcomes are needed. Recently, we developed an algorithm that employs the mutational profile of TP53 as an independent prognostic factor in HNSCC. In this study, we investigated its role as a predictive biomarker of treatment outcomes in HNSCC patients. We also tested the usefulness of two classification systems for TP53 mutational landscapes.

MATERIALS AND METHODS

Clinical and genomic data were retrieved from The Cancer Genome Atlas database. We built a multivariate stepwise backward binary regression model to assess the role of TP53 mutations in predicting therapeutic outcomes.

RESULTS

Cases harbouring high-risk-of-death mutations reported an odds ratio of 3.301 for stable or progressive disease compared to wild-type cases, while no significant difference in treatment outcomes was found between cases with low-risk-of-death mutations and wild-type TP53. Our analysis found that older patients with a history of alcohol consumption had a higher risk of stable/progressive disease.

CONCLUSIONS

This study improves current evidence on the role of TP53 mutations in treatment response in HNSCC patients.

RUVBL1 accelerates tongue squamous cell carcinoma by mediating CRaf/MEK/ERK pathway

RAF/MEK/ERK pathway is frequently activated in tumor. Therefore, this study will investigate the function of RUVBL1 (RAF-binding protein) in tongue squamous cell carcinoma (TSCC). Bioinformatics was performed to identify differentially expressed mRNAs (DE-mRNAs) in TCGA-oral squamous cell carcinoma, GSE13601, and GSE34105 datasets. A total of 672 shared DE-mRNAs were identified in three datasets, and they are regulating metastasis and angiogenesis. Patients with RUVBL1 low expression had high overall survival. Overexpressing RUVBL1 enhanced the viability, wound healing percentage, invasion, sphere formation, angiogenesis, and resistance to cisplatin and 5-fluorouracil in CAL-27 and SCC-4 cells, and the opposite results were obtained by knocking down RUVBL1. Moreover, overexpression of RUVBL1 bolstered tumor growth in vivo. Strikingly, RUVBL1 diminished the phosphorylation of CRAF Ser259, which led to activation of the MEK/ERK pathway. In conclusion, RUVBL1 contributes to the malignant biological behavior of TSCC via activating the CRAF/MEK/ERK pathway. This provides molecular mechanisms and perspectives for targeted therapy of the CRAF/MEK/ERK pathway.

Lingual Denervation Improves the Efficacy of Anti-PD-1 Immunotherapy in Oral Squamous Cell Carcinomas by Downregulating TGFβ Signaling

PURPOSE

Intratumoral nerve infiltration relates to tumor progression and poor survival in oral squamous cell carcinoma (OSCC). How neural involvement regulates antitumor immunity has not been well characterized. This study aims to investigate molecular mechanisms of regulating tumor aggressiveness and impairing antitumor immunity by nerve-derived factors.

EXPERIMENTAL DESIGN

We performed the surgical lingual denervation in an immunocompetent mouse OSCC model to investigate its effect on tumor growth and the efficacy of anti-PD-1 immunotherapy. A trigeminal ganglion neuron and OSCC cell coculture system was established to investigate the proliferation, migration, and invasion of tumor cells and the PD-L1 expression. Both the neuron-tumor cell coculture in vitro model and the OSCC animal model were explored.

RESULTS

Lingual denervation slowed down tumor growth and improved the efficacy of anti-PD-1 treatment in the OSCC model. Coculturing with neurons not only enhanced the proliferation, migration, and invasion but also upregulated TGFβ-SMAD2 signaling and PD-L1 expression of tumor cells. Treatment with the TGFβ signaling inhibitor galunisertib reversed nerve-derived tumor aggressiveness and downregulated PD-L1 on tumor cells. Similarly, lingual denervation in vivo decreased TGFβ and PD-L1 expression and increased CD8+ T-cell infiltration and the expression of IFNγ and TNFα within tumor.

CONCLUSIONS

Neural involvement enhanced tumor aggressiveness through upregulating TGFβ signaling and PD-L1 expression in OSCC, while denervation of OSCC inhibited tumor growth, downregulated TGFβ signaling, enhanced activities of CD8+ T cells, and improved the efficacy of anti-PD-1 immunotherapy. This study will encourage further research focusing on denervation as a potential adjuvant therapeutic approach in OSCC.

SIGNIFICANCE

This study revealed the specific mechanisms for nerve-derived cancer progression and impaired antitumor immunity in OSCC, providing a novel insight into the cancer-neuron-immune network as well as pointing the way for new strategies targeting nerve-cancer cross-talk as a potential adjuvant therapeutic approach for OSCC.

Prognostic factors in surgically treated tongue squamous cell carcinoma in stage T1-2N0-1M0: A retrospective analysis

PURPOSE

The study aimed to retrospectively identify the prognostic factors of surgically treated primary tongue squamous cell carcinoma (TSCC) cases and assess the benefits of surgical neck lymph node dissection (LND) in early-stage cancer.

METHODS

Patients with primary TSCC with pT1-2N0-1M0 stage without distant metastasis who were treated with surgery during 2014-2016 at Xiangya Hospital, Central South University were included. Univariate and multivariate Cox models were constructed to explore prognostic factors of overall survival (OS), disease-free survival (DFS), and local recurrence-free survival (LRFS). Sub-group analysis was used to assess the effect of adjuvant therapy and the prognostic value of LND for the early-stage patients.

RESULTS

In total, 440 patients met the inclusion criteria. During the follow-up period, the 5-year OS, DFS, were 84.4% and 70.0%, respectively. Univariate analysis showed that TNM stage, lymphovascular invasion (LVI), and/or perineural invasion (PNI), pathological differentiation, etc. were significant predictors of OS and DFS. Multivariate analysis showed that TNM stage and the degree of pathological differentiation were independent prognostic factors for all outcomes. Besides, the number of cervical LND could independently predict both DFS and LRFS while LVI/PNI were associated with DFS. And high-quality neck LND (≥30) significantly improved DFS and LRFS for patients of pT1cN0M0 or stage I as compared to those without LND.

CONCLUSIONS

TNM stage and pathological differentiation were crucial prognostic factors for postoperative patients with TSCC. Notably, high-quality cervical LND was beneficial for the improvement of DFS and LRFS for patients of pT1cN0M0 or stage I.

In Vitro and In Vivo Analyses Reveal Tumor-Derived Exosome miR-558 Promotes Angiogenesis in Tongue Squamous Cell Carcinoma by Targeting Heparinase

This study aimed to investigate the role of miR-558 in tumor angiogenesis by targeting heparinase (HPSE) in tongue squamous cell carcinoma (TSCC)-derived exosomes. In the present study, the role of exosome miR-558 in angiogenesis in vitro and in vivo was investigated by cell proliferation, migration, tube formation, subcutaneous tumor formation in mice, and in vivo Matrigel plug assay. The target genes of miR-558 were detected by means of dual luciferase assay. It was found that TSCC cells secrete miR-558 into the extracellular environment, with exosome as the carrier. Human umbilical vein endothelial cells (HUVEC) ingested exosomes, which not only increased the expression level of miR-558, but also enhanced their proliferation, migration, and tube formation functions. In vivo Matrigel plug assay demonstrated that TSCC cell-derived exosome miR-558 promoted neovascularization in vivo. Compared with negative control cells, TSCC cells overexpressing miR-558 formed subcutaneous tumors in nude mice, with larger volume, heavier mass, and more vascularization. Dual luciferase assay confirmed that HPSE was the direct target gene regulated by miR-558. HPSE promoted the proliferation, migration, and tube formation of HUVECs, and the knockout of HPSE could downregulate the pro-angiogenic effect of miR-558. In summary, miR-558 in TSCC exosomes promotes the proliferation, migration, and tube formation of HUVECs by targeting HPSE, and enhancing tumor angiogenesis.

Tumor budding is a prognostic factor in head and neck squamous cell carcinoma: A comprehensive meta-analysis and trial sequential analysis

BACKGROUND

Mortality is linked to tumor budding (TB) in certain neoplasms. TB as a relevant histopathological feature is conditioned by tumor site, a specific study on head and neck squamous cell carcinoma (HNSCC) is needed.

METHODS

A comprehensive meta-analysis was undertaken to investigate the relationship between TB and HNSCC-related outcomes.

RESULTS

Overall 42 studies were included. Patients harboring high TB reported an Overall Survival (OS) Hazard Ratio (HR) of 2.63 (95% confidential interval (CI) 2.04-3.39; p-value < 0.001), Disease-free Survival (DFS) HR of 1.88 (95%CI 1.57-2.24; p-value <0.001) and Disease-specific Survival (DSS) HR of 2.14 (95%CI 1.81-2.52; p-value <0.001). Lymph Node Metastasis (LNM) studies harbored null heterogeneity and marked association with TB (Odds Ratio (OR) = 4.48, 95%CI 2.97-6.76; p-value < 0.001). Trial Sequential Analysis (TSA) supported definitive results for DSS.

CONCLUSION

The study has provided compelling evidence that there is a significant association between TB and a worse prognosis for HNSCC.

Perineural Invasion Is a Significant Prognostic Factor in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

(1) Objectives: This systematic review and meta-analysis aimed to summarize current evidence regarding the prognostic role of perineural invasion (PNI) in patients with oral squamous cell carcinoma (OSCC). (2) Methods: We searched Cochrane Central, ProQuest, PubMed, Scopus, Science Direct, and Web of Science, using relevant keywords to identify eligible articles. Two independent reviewers conducted two-stage screening, data extraction, and quality assessment. The risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) criteria. All analyses were performed using comprehensive meta-analysis (CMA; version 3.3.070) software. (3) Results: The study included 101 published articles encompassing 26,062 patients. The pooled analyses showed that PNI was associated with significantly worse overall survival (OS; HR = 1.45, 95% CI: 1.32-1.58; p < 0.001), worse disease-specific survival (DSS; HR = 1.87, 95% CI: 1.65-2.12; p < 0.001), and worse disease-free survival (DFS; HR = 1.87, 95% CI: 1.65-2.12; p < 0.001). Similarly, both local recurrence-free survival (LRFS) and regional recurrence-free survival (RRFS) were worse in patients with PNI (HR = 2.31, 95% CI: 1.72-3.10, p < 0.001; and HR = 2.04, 95% CI: 1.51-2.74, p < 0.001), respectively. The random-effect estimate of three studies demonstrated that the presence of PNI was associated with worse failure-free survival (FFS; HR = 2.59, 95% CI: 1.12-5.98, p < 0.001). (4) Conclusions: The current evidence suggests that PNI can be used as an independent predictor of the prognosis for patients with OSCC. The presence of PNI was associated with worse OS, DFS, DSS, FFS, and with recurrence. Asian patients and patients with extra-tumoral or peripheral PNI invasion were associated with worse prognosis.

The impact of multifocal perineural invasion in predicting survival in patients with oral squamous cell carcinoma: A multicenter investigation

BACKGROUND

Perineural invasion (PNI) in oral squamous cell carcinoma (OSCC) does not contribute to the current American Joint Committee on Cancer 8th edition (AJCC8) staging manual. This study seeks to validate the effect of multifocal PNI in a large cohort of patients.

METHODS

Patients undergoing primary surgical treatment of OSCC with curative intent between 1995 and 2022 was retrieved from two Australian head and neck databases. PNI was categorized as a single focus or multiple foci. Study end points included disease-specific survival (DSS) and overall survival (OS).

RESULTS

Complete data for survival analysis was available in 993 patients. Multifocal PNI was associated with a 61% increased risk of death due to OSCC (HR 1.61, 95% CI 1.11-2.33, p = 0.014) and a 32% increased risk of death from any cause (HR 1.32, 95% CI 1.01-1.73, p = 0.045).

CONCLUSIONS

Multifocal PNI is a significant predictor of survival in OSCC.

The predictive value of pretreatment hemoglobin-to-platelet ratio on osteoradionecrosis incidence rates of locally advanced nasopharyngeal cancer patients managed with concurrent chemoradiotherapy

BACKGROUND

This retrospective study aimed to investigate whether the pretreatment hemoglobin-to-platelet ratio (HPR) could predict the risk of osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (C-CRT) for locally advanced nasopharyngeal carcinoma (LA-NPC).

METHODS

ORN cases were reported from the records of LA-NPC patients who had oral examinations before and after C-CRT. The pretreatment HPR values were calculated on the first day of C-CRT. The connection between HPR values and ORN occurrences was determined using receiver operating characteristic curve analysis. The primary endpoint was the relationship between the pretreatment HPR values and post-C-CRT ORN incidence rates, while secondary endpoints included the identification of other putative ORN risk factors.

RESULTS

We distinguished 10.9% incidences of ORN during the post-C-CRT follow-up period among 193 LA-NPC patients. The optimal cutoff for pre-C-CRT HPR was 0.48 that grouped the patients into two HPR groups with fundamentally different post-C-CRT ORN incidence rates: Group 1: HPR ≤ 0.48 (N = 60), and Group 2: HPR > 0.48 (N = 133). The comparative analysis indicated a significantly higher ORN incidence in HPR ≤ 0.48 group (30%; P < 0.001). The other factors associated with meaningfully increased ORN rates included the presence of pre-C-CRT ≥ 5 teeth extractions, mandibular volume receiving ≥ 64 Gy, post-C-CRT tooth extractions, mean mandibular dose ≥ 50.6 Gy, and C-CRT to tooth extraction interval > 5.5 months.

CONCLUSION

Low pretreatment HPR levels were independently and unequivocally linked to significantly increased incidence of ORN post-C-CRT. Pre-C-CRT HPR levels may be used to estimate the incidence of ORN and be useful for taking preventive and therapeutic measures in these patients such as monitoring oral hygiene with strict follow-up, avoidance of unnecessary tooth extractions, particularly after C-CRT, and use of more rigorous mandibular RT dose limits.

Prediction of cervical lymph node metastasis from immunostained specimens of tongue cancer using a multilayer perceptron neural network

BACKGROUND

Although cervical lymph node metastasis is an important prognostic factor for oral cancer, occult metastases remain undetected even by diagnostic imaging. We developed a learning model to predict lymph node metastasis in resected specimens of tongue cancer by classifying the level of immunohistochemical (IHC) staining for angiogenesis- and lymphangiogenesis-related proteins using a multilayer perceptron neural network (MNN).

METHODS

We obtained a dataset of 76 patients with squamous cell carcinoma of the tongue who had undergone primary tumor resection. All 76 specimens were IHC stained for the six types shown above (VEGF-C, VEGF-D, NRP1, NRP2, CCR7, and SEMA3E) and 456 slides were prepared. We scored the staining levels visually on all slides. We created virtual slides (4560 images) and the accuracy of the MNN model was verified by comparing it with a hue-saturation (HS) histogram, which quantifies the manually determined visual information.

RESULTS

The accuracy of the training model with the MNN was 98.6%, and when the training image was converted to grayscale, the accuracy decreased to 52.9%. This indicates that our MNN adequately evaluates the level of staining rather than the morphological features of the IHC images. Multivariate analysis revealed that CCR7 staining level and T classification were independent factors associated with the presence of cervical lymph node metastasis in both HS histograms and MNN.

CONCLUSION

These results suggest that IHC assessment using MNN may be useful for identifying lymph node metastasis in patients with tongue cancer.

Extratumoral invasion: A unique phenomenon of aggressive recurrent oropharyngeal squamous cell carcinoma

BACKGROUND

Oropharyngeal squamous carcinomas cause significant morbidity and mortality. Poor prognosticators include lymphovascular and perineural invasion. Extratumoral phenotypes of these histologic findings confer worse prognoses.

METHODS

We report eight cases of recurrent oropharyngeal cancer with diffuse extratumoral lymphovascular invasion (ELVI) or extratumoral perineural invasion (EPNI) and review the existing literature.

RESULTS

On salvage resection for recurrence following primary radiation or chemoradiation, six patients manifested ELVI and two showed EPNI. These patterns conferred difficulty with complete surgical clearance; final pathologic analysis demonstrated positive margins for all eight patients. The six patients with ELVI were p16+ and the two with EPNI were p16-. Currently, two patients are deceased and six patients are alive at an average follow-up of 17.4 months. Of the six living patients, 2 have a new recurrence and are in hospice while 4 have no evidence of disease.

CONCLUSIONS

ELVI and EPNI have received little consideration in the literature as unique histopathologic features of oropharyngeal squamous carcinoma. We present the first series on these adverse extratumoral features in recurrent disease. We call attention to these unique histologic features in the setting of recurrent oropharyngeal cancer to encourage others to track the results of therapeutic intervention and to identify successful strategies for treatment.

Prognostic significance of the neural invasion in oral squamous cell carcinoma

BACKGROUND

Although nerve involvement can predict recurrence and prognosis in oral squamous cell carcinomas, there still have controversies and limitations regarding the standardization for its detection. In this study, we explore the impact of neural invasion in oral squamous cell carcinomas prognosis, comparing intraneural invasion (tumor cells inside nerve structure) and perineural invasion (cells involving the nerve, but not invading its sheath).

METHODS

Surgical slides stained with hematoxylin and eosin from 235 patients with oral squamous cell carcinomas were carefully verified for the presence of intraneural invasion and perineural invasion. The location in the tumor (intratumoral vs. peritumoral) and number of foci (unifocal or multifocal) were also explored. Survival analyses for cancer-specific survival and disease-free survival were performed with Cox proportional model.

RESULTS

Neural invasion was identified in 74 cases, 64.9% displayed intraneural invasion and 35.1% displayed perineural invasion. Univariate analysis revealed a significantly poorer cancer-specific survival, but not disease-free survival, in patients with intraneural invasion, in contrast to cases with perineural invasion that did not achieve significant association with both cancer-specific survival and disease-free survival. Further analyses revealed that the location in the tumor and number of foci had little impact on discriminatory ability of intraneural invasion. Multivariate analysis confirmed that intraneural invasion is significantly and independently associated with poor cancer-specific survival (hazard ratio: 2.50, 95% CI: 1.31-3.79, p = 0.003).

CONCLUSION

This study provides evidence that intraneural invasion, but not perineural invasion, is a relevant predictor of survival in patients with oral squamous cell carcinomas, suggesting that its association with other clinical and pathological prognostic factors should be consider in determining the optimal treatment protocol and prognosis of these patients.

A high pan-immune-inflammation value before chemoradiotherapy indicates poor outcomes in patients with small-cell lung cancer

Objectives: The objective of our study was to assess the prognostic significance of the Pan-Immune-Inflammation Value (PIV) before concurrent chemoradiation (C-CRT) and prophylactic cranial irradiation (PCI) in patients with limited-stage small-cell lung cancer (SCLC). Methods: The medical records of LS-SCLC patients who underwent C-CRT and PCI between January 2010 and December 2021 were retrospectively analyzed. PIV values were calculated using the peripheral blood samples obtained within the past 7 days before the initiation of treatment: PIV = [neutrophils × platelets × monocytes] ÷ lymphocytes. Using receiver operating characteristic (ROC) curve analysis, the optimal pretreatment PIV cutoff values that can partition the study population into two groups with substantially distinct progression-free survival (PFS) and overall survival (OS) outcomes were determined. The relationship between PIV values and OS outcomes was the primary outcome measure. Results: Eighty-nine eligible patients were divided into two PIV groups at an optimal cutoff of 417 [Area under curve (AUC): 73.2%; sensitivity: 70.4%; specificity: 66.7%]: Group 1: PIV < 417 (N = 36) and Group 2: PIV ≥ 417 (N = 53). Comparative analyses revealed that patients with PIV < 417 had significantly longer OS (25.0 vs 14.0 months, p < .001) and PFS (18.0 vs 8.9 months, p = .004) compared to patients with PIV ≥ 417. The outcomes of the multivariate analysis have verified the independent significance of pretreatment PIV concerning PFS (p < .001) and OS (p < .001) outcomes. Conclusion: The findings of this retrospective study indicate that the pretreatment PIV is a reliable and independent prognostic biomarker for patients with LS-SCLC who were treated with C-CRT and PCI.

Spatial and Transcriptomic Analysis of Perineural Invasion in Oral Cancer

PURPOSE

Perineural invasion (PNI), a common occurrence in oral squamous cell carcinomas, is associated with poor survival. Consequently, these tumors are treated aggressively. However, diagnostic criteria of PNI vary and its role as an independent predictor of prognosis has not been established. To address these knowledge gaps, we investigated spatial and transcriptomic profiles of PNI-positive and PNI-negative nerves.

EXPERIMENTAL DESIGN

Tissue sections from 142 patients were stained with S100 and cytokeratin antibodies. Nerves were identified in two distinct areas: tumor bulk and margin. Nerve diameter and nerve-to-tumor distance were assessed; survival analyses were performed. Spatial transcriptomic analysis of nerves at varying distances from tumor was performed with NanoString GeoMx Digital Spatial Profiler Transcriptomic Atlas.

RESULTS

PNI is an independent predictor of poor prognosis among patients with metastasis-free lymph nodes. Patients with close nerve-tumor distance have poor outcomes even if diagnosed as PNI negative using current criteria. Patients with large nerve(s) in the tumor bulk survive poorly, suggesting that even PNI-negative nerves facilitate tumor progression. Diagnostic criteria were supported by spatial transcriptomic analyses of >18,000 genes; nerves in proximity to cancer exhibit stress and growth response changes that diminish with increasing nerve-tumor distance. These findings were validated in vitro and in human tissue.

CONCLUSIONS

This is the first study in human cancer with high-throughput gene expression analysis in nerves with striking correlations between transcriptomic profile and clinical outcomes. Our work illuminates nerve-cancer interactions suggesting that cancer-induced injury modulates neuritogenesis, and supports reclassification of PNI based on nerve-tumor distance rather than current subjective criteria.

The Emerging Impact of Tumor Budding in Oral Squamous Cell Carcinoma: Main Issues and Clinical Relevance of a New Prognostic Marker

Tumor Budding (TB) represents a single cancer cell or a small cluster of less than five cancer cells on the infiltrative tumor front. Accumulating evidence suggests TB is an independent prognostic factor in oral squamous cell carcinoma (OSCC). However, its exact role is not yet elucidated, and a standardized scoring system is still necessary. The study aims to extensively review the literature data regarding the prognostic role of TB in OSCC. The results of TB are an independent prognostic factor of poor survival outcomes in OSCC. To date, the manual detection of hematoxylin and eosin-staining or pancytokeratin-immunostaining sections are the most commonly used methods. Between the several cut-offs, the two-tier system with five buds/field cut-offs provides better risk stratification. The prognostic role of the BD model in predicting survival outcomes was extensively validated; however, the inclusion of DOI, which is already a staging parameter, encouraged other authors to propose other models, integrating TB count with other adverse risk factors, such as the tumor–stroma ratio and tumor-infiltrated lymphocytes. The prognostic relevance of TB in OSCC highlights its evaluation in daily pathological practice. Therefore, the TB detection method and the TB scoring system should be validated based on tumor stage and site.

Pilot Investigation on p75ICD Expression in Laryngeal Squamous Cell Carcinoma

We investigated the p75 Neurotrophin Receptor (p75NTR) expression and cleavage product p75NTR Intracellular Domain (p75ICD) as potential oncogenic and metastatic markers in human Laryngeal Squamous Cell Carcinoma (LSCC). p75NTR is highly expressed in Cancer Stem Cells (CSCs) of the laryngeal epithelia and it has been proposed as a marker for stemness, cell migration, and chemo-resistance in different squamous carcinomas. To investigate the clinical significance of p75NTR cleavage products in solid tumors, full-length and cleaved p75NTR expression was analyzed in laryngeal primary tumors from different-stage LSCC patients, diagnosed at the Policlinico Umberto I Hospital. Molecular and histological techniques were used to detect the expressions of p75NTR and p75ICD, and ATP Binding Cassette Subfamily G Member 2 (ABCG2), a CSC marker. We found regulated p75NTR cleavage during squamous epithelial tumor progression and tissue invasion. Our preliminary investigation suggests p75ICD expression and localization as possible features of tumorigenesis and metastaticity. Its co-localization with ABCG2 in squamous cells in the parenchyma invaded by the tumor formation allows us to hypothesize p75NTR and p75ICD roles in tumor invasion and CSC spreading in LSCC patients. These data might represent a starting point for a comprehensive analysis of p75NTR cleavage and of its clinical relevance as a potential molecular LSCC signature, possibly helping diagnosis, and improving prognosis and personalized therapy.

Evaluated expression of CELSR3 in oral squamous cell carcinoma is associated with perineural invasion and poor prognosis

OBJECTIVE

The objective of this study was to evaluate CELSR3 expression and explore its potential mechanism in oral squamous cell carcinoma.

STUDY DESIGN

CELSR3 mRNA expression was analyzed using The Cancer Genome Atlas (TCGA) database. CELSR3 protein expression in 135 surgical oral squamous cell carcinoma specimens was observed by immunohistochemical staining. Staining results were used to investigate the association between CELSR3 expression and clinicopathologic characteristics and prognosis. Bioinformatics analyses were used to explore the potential mechanism of CELSR3 in head and neck squamous cell carcinoma.

RESULTS

CELSR3 mRNA expression was upregulated in patients with head and neck squamous cell carcinoma in the TCGA head and neck squamous cell carcinoma data set. Increased CELSR3 protein expression was associated with perineural invasion and poor clinical outcomes in patients with oral squamous cell carcinoma. Bioinformatics analyses revealed that CELSR3 is involvement in axonogenesis, neuron migration, and cell-cell adhesion, all of which are involved in the process of perineural invasion.

CONCLUSION

CELSR3 may play a pro-oncogenic role in oral squamous cell carcinoma and can predict perineural invasion and poor survival. CELSR3 may be involved in oral squamous cell carcinoma progression by modulating perineural invasion.

Prognostic significance of tumor budding thresholds in oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) represents the most common malignancy of the oral cavity. Tumor budding (TB) is a reliable prognostic factor in OTSCC; however, a standardized scoring system is not still validated. The study aims to evaluate the prognostic role of TB in 211 OTSCC patients treated between 1997-2018. TB was evaluated on haematoxylin and eosin-stained sections in the hotspot area of the infiltrative front (×200-magnification). It was scored using a two-tier, a three-tier system, and according to BD-model and revised-Grading system. Univariate and multivariate Cox regression analyses of disease-specific survival (DSS) and disease-free survival (DFS) were performed. A p-values<0.05 was considered as statistically significant. The two-tier and three-tier system resulted an independent prognostic factor of DSS. High-risk patients had a 2.21 and 3.08 times-increased probability of poor DSS compared to low-risk group. It is significantly increased even for intermediate-risk group. No significant differences emerged classifying patients according to BD-model and revised-Grading. These data confirm the prognostic value of TB in predicting DSS in OTSCC. Classifying patients in two groups using the 5-buds cut-off significantly discriminates their outcomes. Since the established role of DOI and the poor prognostic value of grading, TB could be considered an independent prognostic marker.

Neck Management in cT1N0 Tongue Squamous Cell Carcinoma as Determined by Sonographic Depth of Invasion

Objectives

To compare the oncologic outcomes in patients with cT1N0 tongue squamous cell carcinoma (SCC) who underwent different neck management strategies stratified by sonographic depth of invasion (DOI).

Methods

The included patients were retrospectively enrolled, and divided into two groups: observation (OBS) and elective neck dissection (END). The regional control (RC) and disease-specific survival (DSS) rates were compared and stratified by sonographic DOI.

Results

The mean sonographic and pathologic DOIs were 3.8 and 3.7 mm, respectively; the two DOIs were significantly correlated (Spearman correlation coefficient 0.974. p <0.001). In patients with sonographic DOI <4.0 mm, the 5-year RC rates were 73 and 89% in the OBS and END groups, respectively, and were not significantly different. However, in patients with sonographic DOI ≥4.0 mm, the 5-year RC rate was significantly different between the OBS (57%) and END (80%) groups (p = 0.031). In patients with sonographic DOI <4.0 mm, the 5-year DSS rates were 79 and 89% in OBS and END groups, respectively, and were not significantly different. However, in patients with sonographic DOI ≥4.0 mm, the 5-year DSS rate was significantly different between the OBS (67%) and END (86%) groups (p = 0.033).

Conclusions

Sonographic DOI was notably correlated with pathologic DOI. Moreover, there was a significant survival difference between the OBS and END groups in cT1N0 tongue SCC patients with sonographic DOI ≥4.0 mm but not in those with sonographic DOI <4.0 mm. Our study provides a useful method to aid decision-making in the clinical setting for this patient group.

Worst Pattern of Perineural Invasion Redefines the Spatial Localization of Nerves in Oral Squamous Cell Carcinoma

As a key histopathological characteristic of tumor invasion, perineural invasion (PNI) assists tumor dissemination, whereas the current definition of PNI by dichotomy is not accurate and the prognostic value of PNI has not reached consensus. To define PNI status in each patient when mixed types of PNI occurred simultaneously, we here further subclassified the traditional PNI in 183 patients with oral squamous cell carcinoma (OSCC). The spatial localization of nerves in OSCC microenvironment was thoroughly evaluated and successfully concluded into four types of PNI: 0, tumor cells away from nerves; 1, tumor cells encircling nerves less than 33%; 2, tumor cells encircling nerves at least 33%; and 3, tumor cells infiltrating into nerve sheathes. Sequentially, patients were stratified by single and mixed types of PNI. Traditionally, types 0 and 1 were defined as PNI^-, while types 2 and 3 were PNI⁺, which predicted shorter survival time. When multiple types of PNI existed within one tumor, patients with higher score of PNI types tended to have a relatively worse prognosis. Therefore, to define the status of PNI more precisely, the new variable worst pattern of PNI (WPNI) was proposed, which was taken as the highest score of PNI types present in each patient no matter how focal. Results showed that patients with WPNI 1 had longest survival time, and WPNI 2 correlated with better overall survival (p = 0.02), local-regional recurrence-free survival (p = 0.03), and distant metastasis-free survival (p = 0.046) than WPNI 3. Multivariate Cox analysis confirmed that only WPNI 3 could independently predict patients' prognosis, which could be explained by a more damaged immune response in WPNI 3 patients with less CD3⁺CD8⁺ T cells and CD19⁺ B cells. Conclusively, WPNI by trichotomy provide more meticulous and precise pathological information for tumor-nerve interactions in OSCC patients.

Molecular and Cellular Mechanisms of Perineural Invasion in Oral Squamous Cell Carcinoma: Potential Targets for Therapeutic Intervention

Simple Summary

Squamous cell carcinoma is the most common type of oral cavity cancer. It can spread along and invade nerves in a process called perineural invasion. Perineural invasion can increase the chances of tumor recurrence and reduce survival in patients with oral cancer. Understanding how oral cancer interacts with nerves to facilitate perineural invasion is an important area of research. Targeting key events that contribute to perineural invasion in oral cavity cancer may reduce tumor recurrence and improve survival. In this review, we describe the impact of perineural invasion in oral cancer and the mechanisms that contribute to perineural invasion. Highlighting the key events of perineural invasion is important for the identification and testing of novel therapies for oral cancer with perineural invasion.

Abstract

The most common oral cavity cancer is squamous cell carcinoma (SCC), of which perineural invasion (PNI) is a significant prognostic factor associated with decreased survival and an increased rate of locoregional recurrence. In the classical theory of PNI, cancer was believed to invade nerves directly through the path of least resistance in the perineural space; however, more recent evidence suggests that PNI requires reciprocal signaling interactions between tumor cells and nerve components, particularly Schwann cells. Specifically, head and neck SCC can express neurotrophins and neurotrophin receptors that may contribute to cancer migration towards nerves, PNI, and neuritogenesis towards cancer. Through reciprocal signaling, recent studies also suggest that Schwann cells may play an important role in promoting PNI by migrating toward cancer cells, intercalating, and dispersing cancer, and facilitating cancer migration toward nerves. The interactions of neurotrophins with their high affinity receptors is a new area of interest in the development of pharmaceutical therapies for many types of cancer. In this comprehensive review, we discuss diagnosis and treatment of oral cavity SCC, how PNI affects locoregional recurrence and survival, and the impact of adjuvant therapies on tumors with PNI. We also describe the molecular and cellular mechanisms associated with PNI, including the expression of neurotrophins and their receptors, and highlight potential targets for therapeutic intervention for PNI in oral SCC.

Prognostic factors in salvage surgery for recurrent head and neck cancer: A systematic review and meta-analysis

INTRODUCTION

Although salvage surgery (SS) is considered the best curative choice in recurrent head and neck cancer, the identification of patients who can benefit the most from this treatment is challenging.

METHODS

We systematically reviewed the prognostic role of pre- and post-surgery factors in patients undergoing SS for recurrent head and neck cancer (oral cavity, oropharynx, hypopharynx, and larynx).

RESULTS

Twenty-five studies met the inclusion criteria out of 1280 screened citations. Pre-surgery factors significantly associated with worse overall survival were age>60 years, advanced initial stage, early recurrence, and regional recurrence; no heterogeneity between study emerged. Among post- surgery factors, worse survival emerged for positive surgical margins, extracapsular extension and perineural invasion.

CONCLUSION

The identification of pre-surgery factors associated with poor outcomes may help the selection of the best candidate to SS; alternative treatments should be considered for high-risk patients. Post-surgery predictors of worse prognosis may guide clinicians in tailoring patients' surveillance.

Progression Risk Score Estimation Based on Immunostaining Data in Oral Cancer Using Unsupervised Hierarchical Clustering Analysis: A Retrospective Study in Taiwan

This study aimed to investigate whether the progression risk score (PRS) developed from cytoplasmic immunohistochemistry (IHC) biomarkers is available and applicable for assessing risk and prognosis in oral cancer patients. Participants in this retrospective case-control study were diagnosed between 2012 and 2014 and subsequently underwent surgical intervention. The specimens from surgery were stained by IHC for 16 cytoplasmic target markers. We evaluated the results of IHC staining, clinical and pathological features, progression-free survival (PFS), and overall survival (OS) of 102 oral cancer patients using a novel estimation approach with unsupervised hierarchical clustering analysis. Patients were stratified into high-risk (52) and low-risk (50) groups, according to their PRS; a metric consisting of cytoplasmic PLK1, PhosphoMet, SGK2, and SHC1 expression. Moreover, PRS could be extended for use in the Cox proportional hazard regression model to estimate survival outcomes with associated clinical parameters. Our study findings revealed that the high-risk patients had a significantly increased risk in cancer progression compared with low-risk patients (hazard ratio (HR) = 2.20, 95% confidence interval (CI) = 1.10-2.42, p = 0.026). After considering the influences of demographics, risk behaviors, and tumor characteristics, risk estimation with PRS provided distinct PFS groups for patients with oral cancer (p = 0.017, p = 0.019, and p = 0.020). Our findings support that PRS could serve as an ideal biomarker for clinical use in risk stratification and progression assessment in oral cancer.

Prognostic Value of Perineural Invasion in Oral Tongue Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

OBJECTIVES

A significant number of recently published research has outlined the contribution of perineural invasion (PNI) to clinical outcomes in oral tongue squamous cell carcinoma (OTSCC), but some results remain conflicting. This study aimed to determine whether patients with OTSCC with PNI have a worse prognosis than those without PNI.

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Library were queried for potentially eligible articles published up to December 2020. The primary outcomes were the hazard ratio (HR) for locoregional recurrence, overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS). The random-effect model was used in all analyses.

RESULTS

Seventeen studies (4445 patients) were included. Using adjusted HRs, the presence of PNI was associated with a higher risk of locoregional recurrence (HR=1.73, 95%CI: 1.07-2.79, P=0.025, I2 = 33.1%, Pheterogeneity=0.224), worse OS (HR=1.94, 95%CI: 1.39-2.72, P<0.001, I2 = 0.0%, Pheterogeneity=0.838), worse DFS (HR=2.13, 95%CI: 1.53-2.96, P<0.001, I2 = 48.4%, Pheterogeneity=0.071), and worse CSS (HR=1.93, 95%CI: 1.40-2.65, P<0.001, I2 = 25.5%, Pheterogeneity=0.251). PNI had an impact on locoregional recurrence in early-stage OTSCC but not in all stages, and on OS, DFS, and CSS in all-stage and early-stage OTSCC. The sensitivity analyses showed that the results were robust.

CONCLUSION

The presence of PNI significantly affects the locoregional recurrence and survival outcomes among patients with OTSCC.