Prognostic impact of extratumoral perineural invasion in patients with oral cavity squamous cell carcinoma

Subcategorization of Perineural Invasion Stratifies Oral Cavity Squamous Cell Carcinoma Prognosis

OBJECTIVE

To evaluate whether subcategorization of perineural invasion (PNI) improves the prognostic resolution of the American Joint Committee on Cancer, Eighth Edition (AJCC8) staging system in oral cavity squamous cell carcinoma (OCSCC).

METHODS

OCSCC tumor specimens from patients seen at a tertiary care institution who underwent primary surgical resection between January 2019 and June 2021 were sorted into four PNI categories: negative, intratumoral, peripheral, and extratumoral. The prognostic effect of these PNI categories were assessed through Kaplan-Meier, Cox regression, and log-rank testing using recurrence-free survival (RFS) and overall survival (OS) as primary and secondary outcomes respectively.

RESULTS

A total of 158 patients were examined. The median follow-up time was 21 months. PNI subcategorization further stratified RFS (p = 0.007) and OS (p = 0.002). Extratumoral PNI was associated with a 4.5-fold increase in recurrence risk (adjusted hazards ratio [aHR]: 4.53; 95% confidence interval [CI]: 1.1-18.66) and worse OS when compared with PNI negative disease (aHR: 5.71; 95% CI: 1.0-32.67). Peripheral PNI was associated with worse OS (aHR: 5.7; 95% CI: 1.35-24.08) but not worse RFS (p = 0.18) when compared with PNI negative disease. Interestingly, intratumoral PNI was not associated with significant differences in RFS (p = 0.087) or OS (p = 0.22) when compared with PNI negative disease.

CONCLUSIONS

Subcategorization of OCSCC tumors into extratumoral, peripheral, and intratumoral PNI stratifies RFS and OS when compared with patients with PNI negative disease in an incremental fashion. This pilot study suggests that there may be added benefit in subcategorization of PNI in the prognostic evaluation of OCSCC.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1656-1662, 2024.

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.

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

BACKGROUND

Survival rate for oral tongue squamous cell carcinoma (OTSCC) is still poor and, despite Tumor-Node-Metastasis staging system has been recently updated, patients included under the same stage still show difference in prognosis. Perineural invasion (PNI) emerged to be an indicator of tumor aggressive behavior and unfortunate events. In this study, we investigate the clinic and prognostic value of PNI in a cohort of OTSCC patients.

METHODS

About 200 patients with OTSCC were retrospectively evaluated the presence of PNI. PNI was furtherly descripted as uni-/multifocal and as intra-/peritumoral. Disease-Specific and Relapse-Free Survival (DSS; RFS) were estimated; moreover, we included PNI in the current AJCC 8th Staging System, improving the prognostication model.

RESULTS

Perineural invasion was found in 40.5% of patients. Intratumoral PNI predicted patients at high risk of being diagnosed with lymph-node metastasis. Tumors with positive PNI reported a worse DSS (Hazard Ratio=1.878, p-value = 0.008). Moreover, patients exhibiting both multifocal intra- and peritumoral PNI reported poorest DSS (Hazard Ratio = 2.409, p-value = 0.010). Patients were reclassified in a new staging system in case of multifocal PNI, providing better stratification capacity.

CONCLUSIONS

Perineural invasion might serve as an additional prognostic factor in OTSCC, and by integrating PNI in the staging system, further improvements in prognostication might be reached.

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.

[Staging cancers of the oral cavity according to the 8th edition of AJCC TNM system: Issues and recommendations]

Stage of cancer at the time of the diagnosis is a key factor for the prognosis and the determination of appropriate treatment. Several cancer staging systems are used worldwide. The most useful staging system is the tumor, node and metastasis (TNM) staging system develop by the American Joint Committee on Cancer (AJCC) in collaboration with the Union for International Cancer Control (UICC) referred to as the AJCC TNM staging system. The AJCC TNM system classifies cancers by the size and extend of the primary tumor (T), involvement of regional lymph nodes (N) and the presence of distant metastases (M). AJCC and UICC periodically modify the AJCC TNM staging system according to newly acquired clinical, pathological and biological data improving understanding of cancer physiopathology. The 8th edition of AJCC TNM system is effective for cancer patients diagnosed on or after January 1, 2018. Here, we report the issues of the staging cancers of the oral cavity according to the 8th edition of AJCC TNM system. We focus on 2 new concepts defined in the 8th edition of AJCC TNM system: depth of invasion (DOI) and extranodal extension (ENE).

The GAL/GALR2 axis promotes the perineural invasion of salivary adenoid cystic carcinoma via epithelial-to-mesenchymal transition

BACKGROUND

Perineural invasion (PNI) is a typical pathological characteristic of salivary adenoid cystic carcinoma (SACC) and other neurotrophic cancers. The mechanism of the neural microenvironment controlling tumor progression during the PNI process is unclear. In the present study, we investigated the role and molecular mechanisms of nerve-derived neuropeptide galanin (GAL) and its receptor (GALR2) in the regulation of PNI in SACC.

METHODS

Immunohistochemistry staining and clinical association studies were performed to analyze the expression of GAL and GALR2 in SACC tissues and their clinical value. Dorsal root ganglion or SH-SY5Y cells were co-cultured with SACC cells in vitro to simulate the interactions between the neural microenvironment and tumor cells, and a series of assays including transcriptome sequencing, Western blot, and Transwell were performed to investigate the role and molecular mechanism of GAL and GALR2 in the regulation of SACC cells. Moreover, both the in vitro and in vivo PNI models were established to assess the potential PNI-specific therapeutic effects by blocking the GAL/GALR2 axis.

RESULTS

GAL and GALR2 were highly expressed in SACC tissues, and were associated with PNI and poor prognosis in SACC patients (p < 0.05). Nerve-derived GAL activated GALR2 expression in SACC cells and induced epithelial-to-mesenchymal transition (EMT) in SACC cells. Adding human recombinant GAL to the co-culture system promoted the proliferation, migration, and invasion of SACC cells significantly, but inhibited the apoptosis of SACC cells. Adding M871, a specific antagonist of GALR2, significantly blocked the above effects (p < 0.05) and inhibited the PNI of SACC cells in vitro and in vivo (p < 0.05).

CONCLUSIONS

This study demonstrated that nerve-derived GAL activated GALR2 expression, and promoted EMT in SACC cells, thereby enhancing the PNI process. Interruption of the GAL/GALR2 axis might be a novel strategy for anti-PNI therapy for SACC.

Perineural invasion and perineural spread in periocular squamous cell carcinoma

Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) of the periocular region is a prognostic marker of adverse tumour outcomes. PNI carries a well-established risk of tumour recurrence, regional metastasis and higher likelihood of mortality. This review will explore and stratify the risks conferred by histological PNI parameters. The radiological features of perineural spread (PNS) and the imaging sequences that delineate these findings will also be highlighted. Surgical excision with en face margin control is the preferred technique for achieving histological clearance. Adjuvant radiotherapy improves treatment outcomes in the setting of concomitant high-risk features. For locally advanced or metastatic cutaneous SCC, immunotherapy represents a novel treatment alternative. This review will provide an algorithm for the diagnosis and management of periocular SCC with PNI and PNS.

Neural Component of the Tumor Microenvironment in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive primary malignancy of the pancreas, with a dismal prognosis and limited treatment options. It possesses a unique tumor microenvironment (TME), generating dense stroma with complex elements cross-talking with each other to promote tumor growth and progression. Diversified neural components makes for not having a full understanding of their influence on its aggressive behavior. The aim of the study was to summarize and integrate the role of nerves in the pancreatic tumor microenvironment. The role of autonomic nerve fibers on PDAC development has been recently studied, which resulted in considering the targeting of sympathetic and parasympathetic pathways as a novel treatment opportunity. Perineural invasion (PNI) is commonly found in PDAC. As the severity of the PNI correlates with a poorer prognosis, new quantification of this phenomenon, distinguishing between perineural and endoneural invasion, could feature in routine pathological examination. The concepts of cancer-related neurogenesis and axonogenesis in PDAC are understudied; so, further research in this field may be warranted. A better understanding of the interdependence between the neural component and cancer cells in the PDAC microenvironment could bring new nerve-oriented treatment options into clinical practice and improve outcomes in patients with pancreatic cancer. In this review, we aim to summarize and integrate the current state of knowledge and future challenges concerning nerve-cancer interactions in PDAC.

Epigenetic Regulations of Perineural Invasion in Head and Neck Squamous Cell Carcinoma

Carcinomas of the oral cavity and oropharynx belong among the ten most common malignancies in the human population. The prognosis of head and neck squamous cell carcinoma (HNSCC) is determined by the degree of invasiveness of the primary tumor and by the extent of metastatic spread into regional and distant lymph nodes. Moreover, the level of the perineural invasion itself associates with tumor localization, invasion's extent, and the presence of nodal metastases. Here, we summarize the current knowledge about different aspects of epigenetic changes, which can be associated with HNSCC while focusing on perineural invasion (PNI). We review epigenetic modifications of the genes involved in the PNI process in HNSCC from the omics perspective and specific epigenetic modifications in OSCC or other neurotropic cancers associated with perineural invasion. Moreover, we summarize DNA methylation status of tumor-suppressor genes, methylation and demethylation enzymes and histone post-translational modifications associated with PNI. The influence of other epigenetic factors on the HNSCC incidence and perineural invasion such as tobacco, alcohol and oral microbiome is overviewed and HPV infection is discussed as an epigenetic factor associated with OSCC and related perineural invasion. Understanding epigenetic regulations of axon growth that lead to tumorous spread or uncovering the molecular control of axon interaction with cancer tissue can help to discover new therapeutic targets for these tumors.

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.

The Impact of Histopathological Features on the Prognosis of Oral Squamous Cell Carcinoma: A Comprehensive Review and Meta-Analysis

OBJECTIVE

Over many decades, studies on histopathological features have not only presented high-level evidence of contribution for treatment directions and prognosis of oral squamous cell carcinoma (OSCC) but also provided inconsistencies, making clinical application difficult. The 8th TNM staging system of OSCC has acknowledged the importance of some histopathological features, by incorporating depth of invasion (DOI) to T category and extranodal extension (ENE) to N category. The aim of this systematic review with meta-analysis is to determine the most clinically relevant histopathological features for risk assessment and treatment planning of OSCC and to elucidate gaps in the literature.

METHODS

A systematic review was conducted using PRISMA guidelines, and the eligibility criteria were based on population, exposure, comparison, outcome, and study type (PECOS). PubMed, Cochrane, Scopus, and Web of Science were searched for articles exploring the impact of histopathological features on OSCC outcomes with Cox multivariate analysis. Pooled data were subjected to an inverse variance method with random effects or fixed effect model, and the risk of bias was evaluated using quality in prognosis studies (QUIPS). Quality of evidence was assessed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

The study included 172 articles published from 1999 to 2021. Meta-analyses confirmed the prognostic potential of DOI, ENE, perineural invasion, lymphovascular invasion, and involvement of the surgical margins and brought promising results for the association of bone invasion, tumor thickness, and pattern of invasion with increased risk for poor survival. Although with a small number of studies, the results also revealed a clinical significance of tumor budding and tumor-stroma ratio on predicted survival of patients with OSCC. Most of the studies were considered with low or moderate risk of bias, and the certainty in evidence varied from very low to high.

CONCLUSION

Our results confirm the potential prognostic usefulness of many histopathological features and highlight the promising results of others; however, further studies are advised to apply consistent designs, filling in the literature gaps to the pertinence of histopathological markers for OSCC prognosis.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), identifier CRD42020219630.

MAGE-A3 is a prognostic biomarker for poor clinical outcome in cutaneous squamous cell carcinoma with perineural invasion via modulation of cell proliferation

Perineural invasion is a pathologic process of neoplastic dissemination along and invading into the nerves. Perineural invasion is associated with aggressive disease and a greater likelihood of poor outcomes. In this study, 3 of 9 patients with cutaneous squamous cell carcinoma and perineural invasion exhibited poor clinical outcomes. Tumors from these patients expressed high levels of MAGE-A3, a cancer testis antigen that may contribute to key processes of tumor development. In addition to perineural invasion, the tumors exhibited poor differentiation and deep invasion and were subsequently classified as Brigham and Women's Hospital tumor stage 3. Cyclin E, A and B mRNA levels were increased in these tumors compared with normal skin tissues (102.93±15.03 vs. 27.15±4.59, 36.83±19.41 vs. 11.59±5.83, 343.77±86.49 vs. 95.65±29.25, respectively; p<0.05). A431 cutaneous squamous cell carcinoma cells pretreated with MAGE-A3 antibody exhibited a decreased percentage S-phase cells (14.13±2.8% vs. 33.97±1.1%; p<0.05) and reduced closure in scratch assays (43.88±5.49% vs. 61.17±3.97%; p = 0.0058). In a syngeneic animal model of squamous cell carcinoma, immunoblots revealed overexpression of MAGE-A3 and cyclin E, A, and B protein in tumors at 6 weeks. However, knockout of MAGE-A3 expression caused a reduction in tumor growth (mean tumor volume 155.3 mm3 vs. 3.2 mm3) compared with parental cells. These results suggest that MAGE-A3 is a key mediator in cancer progression. Moreover, elevated collagen XI and matrix metalloproteases 3, 10, 11, and 13 mRNA levels were observed in poorly differentiated cutaneous squamous cell carcinoma with perineural invasion compared with normal skin tissue (1132.56±882.7 vs. 107.62±183.62, 1118.15±1109.49 vs. 9.5±5, 2603.87±2385.26 vs. 5.29±3, 957.95±627.14 vs. 400.42±967.66, 1149.13±832.18 vs. 19.41±35.62, respectively; p<0.05). In summary, this study highlights the potential prognostic value of MAGE-A3 in clinical outcomes of cutaneous squamous cell carcinoma patients.

Histological features and survival in young patients with HPV-negative oral squamous cell carcinoma

OBJECTIVES

The frequency of oral squamous cell carcinoma in young adults has increased in the last decades, and there are conflicting results in literature about its prognosis in young subjects. The aim of this study was to analyse the clinical and pathological features of oral squamous cell carcinoma in a cohort of young adults in order to investigate the presence of new independent prognostic markers.

MATERIALS AND METHODS

Only HPV-negative young patients (under 40-year-old) affected by oral squamous cell carcinoma were considered in this study. Clinical and pathological data were collected. Patients were re-staged according to the 8th edition of AJCC.

RESULTS

Overall, 66 patients were considered in this study. Perineural invasion significant correlated with both 7th and 8th edition of AJCC, and lymphovascular invasion (p-value < .05). The multivariate survival analysis showed that patients with perineural invasion had a significant worse prognosis (HR = 6.384 95% C.I. 1.304-31.252; p-value = .022).

CONCLUSIONS

Perineural invasion emerged as an independent prognostic factor for disease-specific survival in young patients with oral squamous cell carcinoma. Furthermore, the evaluation of this parameter is simple, inexpensive and can be used to augment the risk stratification of oral cancer based on the 8th edition of AJCC.

Integrating the Tumor Microenvironment into Cancer Therapy

Tumor progression is mediated by reciprocal interaction between tumor cells and their surrounding tumor microenvironment (TME), which among other factors encompasses the extracellular milieu, immune cells, fibroblasts, and the vascular system. However, the complexity of cancer goes beyond the local interaction of tumor cells with their microenvironment. We are on the path to understanding cancer from a systemic viewpoint where the host macroenvironment also plays a crucial role in determining tumor progression. Indeed, growing evidence is emerging on the impact of the gut microbiota, metabolism, biomechanics, and the neuroimmunological axis on cancer. Thus, external factors capable of influencing the entire body system, such as emotional stress, surgery, or psychosocial factors, must be taken into consideration for enhanced management and treatment of cancer patients. In this article, we review prognostic and predictive biomarkers, as well as their potential evaluation and quantitative analysis. Our overarching aim is to open up new fields of study and intervention possibilities, within the framework of an integral vision of cancer as a functional tissue with the capacity to respond to different non-cytotoxic factors, hormonal, immunological, and mechanical forces, and others inducing stroma and tumor reprogramming.

Are Oral Pain and Otalgia Predictive of Perineural Invasion in Squamous Cell Carcinoma of the Oral Tongue?

PURPOSE

Tongue cancer is often associated with pain and perineural invasion. The purpose of the present study was to determine the association between tongue pain and otalgia and the microscopic identification of perineural invasion (PNI) in patients with squamous cell carcinoma of the tongue (SCCOT).

PATIENTS AND METHODS

A retrospective cohort study was performed of patients with a diagnosis of SCCOT from January 2013 through June 2019. Patients without a history of head and neck cancer, who had SCCOT diagnosed and treated surgically by a single surgeon, were included in the present study. The primary predictor variables were tongue pain and otalgia (presence vs absence of both). Other variables included patient demographic data and TNM stage. The primary outcome variable was the histologic presence of PNI. A χ² analysis was performed to test for any significant associations between pain, T stage, and overall stage in relation to PNI outcome. Multivariate logistic regression analysis was used to control for cancer staging variables when testing the association between pain and PNI.

RESULTS

The sample included 128 subjects, of whom 76 were men. Their mean age was 60 years. Most patients (n = 97; 75.8%) complained of tongue pain and a few (n = 50; 39.1%) complained of otalgia. The patients with otalgia had a 3.15 times greater odds of PNI when controlling for T stage (P = .016) and 3.68 times greater odds of PNI when controlling for overall stage (P = .007). Increasing T stage and overall stage-with the exception of stage II-were also significantly associated with PNI (P ≤ .05).

CONCLUSIONS

Our study has demonstrated a statistically significant association between preoperative otalgia and PNI in a consecutive group of patients presenting with newly diagnosed SCCOT.

Complexity of Neural Component of Tumor Microenvironment in Prostate Cancer

The tumor microenvironment (TME) plays an essential role in the development and progression of neoplasms. TME consists of the extracellular matrix and numerous specialized cells interacting with cancer cells by paracrine and autocrine mechanisms. Tumor axonogenesis and neoneurogenesis constitute a developing area of investigation. Prostate cancer (PC) is one of the most common malignancies in men worldwide. During the past years, more and more studies have shown that mechanisms leading to the development of PC are not confined only to the epithelial cancer cell, but also involve the tumor stroma. Different nerve types and neurotransmitters present within the TME are thought to be important factors in PC biology. Moreover, perineural invasion, which is a common way of PC spreading, in parallel creates the neural niche for malignant cells. Cancer neurobiology seems to have become a new discipline to explore the contribution of neoplastic cell interactions with the nervous system and the neural TME component, also to search for potential therapeutic targets in malignant tumors such as PC.

Prognostic impact of extratumoral perineural invasion in patients with oral cavity squamous cell carcinoma

PURPOSE

Perineural invasion (PNI) is an adverse prognostic factor in patients with oral cavity squamous cell carcinoma (OCSCC). The American Joint Committee on Cancer Staging Manual, eighth edition, introduced a subdivision of PNI into two distinct forms, that is, extratumoral and intratumoral PNI (EPNI and IPNI, respectively). We designed the current study to assess whether EPNI and IPNI have different prognostic implications in terms of disease control and survival outcomes in patients with OCSCC.

MATERIALS AND METHODS

We retrospectively examined 229 consecutive patients with OCSCC and PNI who underwent radical surgery between July 2003 and November 2016. EPNI and IPNI were identified in 76 and 153 patients, respectively. The 5-year locoregional control (LRC), distant metastasis, disease-free survival (DFS), and overall survival (OS) rates served as the main outcome measures.

RESULTS

Compared with patients showing IPNI, those with EPNI had a higher prevalence of worst pattern of invasion type-5 (P < 0.001), alcohol consumption (P = 0.03), and close margins (P = 0.002). Univariate analysis revealed that EPNI was a significant predictor of 5-year LRC (P = 0.024), DFS (P = 0.007), and OS (P = 0.034) rates. After allowance for potential confounders in multivariable analysis, ENPI was retained in the model as an independent predictor of 5-year LRC (P = 0.028), DFS (P = 0.011), and OS (P = 0.034) rates.

CONCLUSION

Compared with IPNI, the presence of EPNI in OCSCC portends less favorable outcomes. Patients with EPNI are potential candidates for definite aggressive treatment modalities aimed at improving prognosis.