Acantholytic squamous cell carcinoma of the oral cavity: a more aggressive entity?

Acantholytic squamous cell carcinoma is a histologically distinct variant of squamous cell carcinoma that arises most commonly in areas of the skin exposed to the sun. It is rare on mucosal surfaces of the upper aerodigestive tract, where there is some suggestion that it might behave more aggressively than conventional squamous cell carcinoma. This case which describes a 56-year-old patient presenting with Stage II disease of the tongue who succumbed to disease nine months after presentation despite aggressive multi-modality treatment adds weight to that argument.     

Does invasion of oral squamous cell carcinoma occur into a non-pathological fracture of the mandible?

Although the route of invasion of oral squamous cell carcinoma into the intact mandible is well-documented we know of no reports about whether malignant cells invade through non-pathological fractures. A 68-year-old patient presented with a traumatic fracture of the mandible at the site of an existing carcinoma. He had asegmental resection but histological examination showed no evidence of invasion into the bone.     

Matrix metalloproteinases: do they play a role in mucosal pathology of the oral cavity?

Matrix metalloproteinases (MMPs) are critical factors in maintaining the integrity of mucosa and mediating normal biological processes. An imbalance between tissue levels of these mediators and their natural inhibitors is believed to underlie the pathophysiology of many diseases, including those affect the gastrointestinal and oral mucosae. The ongoing development of synthetic inhibitors of these mediators may provide opportunities to develop treatment modalities for patients suffering from these diseases. Understanding the role of MMPs in the pathophysiology of many diseases, however, is far from complete, and the improvement of pharmaceutical management strategies can only be achieved if the underlying process of these diseases is completely comprehended. This paper reviews the functions of matrix metalloproteinases and addresses their role in mediating mucosal pathologies with emphasis on oral mucosa.     

Field change and oral cancer: new evidence for widespread carcinogenesis?

Patients with oral squamous cell carcinoma (OSCC) are at risk of developing second or multiple primary cancers as a result of field cancerization in the upper aerodigestive tract. In order to quantify the incidence of field change observable in oral mucosa, 26 consecutive new (untreated) patients presenting with a unilateral OSCC (18) or a premaligant lesion (eight) underwent 'mirror image' biopsies from clinically normal-looking mucosa at corresponding anatomical sites. A total of 15 patients (58%) demonstrated histologically abnormal tissue upon microscopic examination: six showed reactive change/cellular atypia associated with chronic irritation, seven exhibited frank dysplasia, whilst two displayed carcinoma-in-situ (CIS) or microinvasive SCC. Although not statistically significant, there was an observable trend for the lateral/ventral tongue and floor of mouth to display increased vulnerability to dysplastic change.     

Clinical behavior of T1–T2 squamous cell carcinoma of the oral cavity

ObjectivesThe main aim of the present study is to analyze the differences in the clinical behavior of pT1 and pT2 oral squamous cell carcinoma of the oral cavity and the importance of tumor thickness in these groups of patients.MethodsA retrospective analysis was conducted using the records of patients diagnosed with pT1 and pT2 oral squamous cell carcinoma between 2006 and 2015 to identify significant differences between these two groups of patients. Several pathological features such as T-stage, N-stage, tumor thickness, surgical margins, and locoregional failure were analyzed.Results194 patients were included in this study. Tumor thickness >0.4 cm was significantly related with nodal involvement and overall survival (p < 0.001). T and N stage, tumor thickness, extracapsular spread and surgical margins were associated with poorer outcomes in terms of overall survival (p < 0.001).ConclusionTumor thickness represents an extremely important prognostic factor and to include depth of invasion (DOI) in the staging of oral squamous cell carcinoma will help in the choice of better treatment strategies and to improve overall survival.     

Is podoplanin expression associated with the proliferative activity of ameloblastomas?

Oral Diseases (2012) 18 , 673–679 Objectives: The aim of this study was to investigate the relationship between podoplanin expression and proliferative activity of ameloblastomas and remnants of the odontogenic epithelium from dental follicles (DF) of unerupted teeth. Subjects and methods: Thirty‐three paraffin‐embedded ameloblastomas and thirty‐two DF obtained of unerupted teeth were analyzed by immunohistochemistry using anti‐human podoplanin and anti‐Ki‐67 antibodies. Podoplanin expression in odontogenic epithelial cells was evaluated using a scoring method, and the Ki‐67 labeling index was determined by the percentage of positive odontogenic cells. Results: All ameloblastomas displayed podoplanin expression in ameloblast‐like cells of the epithelial islands. Membranous expression of podoplanin in ameloblastomas was stronger than in the remnants of odontogenic epithelium (P = 0.001). Statistically significant difference was observed between the cytoplasmic and membranous expression of podoplanin in the remnants of odontogenic epithelium (P = 0.001). The index of epithelial odontogenic proliferative activity, verified by Ki‐67 expression, was higher in ameloblastomas vs remnants of odontogenic epithelium (P < 0.001). No statistically significant correlation was identified between podoplanin and the cellular odontogenic proliferative activity in ameloblastomas and DF (P > 0.05). Conclusions: These results provide evidence that there is no connection between podoplanin immunostaining and odontogenic cellular proliferative activity and suggest a role for membranous podoplanin expression in the local invasion of ameloblastomas.     

What has the National Cancer Database taught us about oral cavity squamous cell carcinoma?

The wealth of data in the National Cancer Database (NCDB) has allowed numerous studies investigating patient, disease, and treatment-related factors in oral cavity squamous cell carcinoma (OCSCC); however, to date, no summation of these studies has been performed. The aim of this study was to provide a concise review of the NCDB studies on OCSCC, with the hopes of providing a framework for future, novel studies aimed at enhancing our understanding of clinical parameters related to OCSCC. Two databases were searched, and 27 studies published between 2002 and 2020 were included. The average sample size was 13,776 patients (range 356–50,896 patients). Four areas of research focus were identified: demographic and socioeconomic status, diagnosis, prognosis, and treatment. This review highlights the impact of age, sex, ethnicity, and socioeconomic status on the prognosis and management of OCSCC, describes the prognostic factors, and details the modalities and indications for neck dissection and adjuvant therapy in OCSCC. In conclusion, the NCDB is a very valuable resource for clinicians and researchers involved in the management of OCSCC, offering an incomparable perspective on a large dataset of patients. Future developments regarding hospital information management, review of data accuracy and completeness, and wider accessibility will help clinicians to improve the care of patients affected by OCSCC.     

Anatomical locations in the oral cavity where surgical resections of oral squamous cell carcinomas are associated with a close or positive margin—a retrospective study

Clinical Oral Investigations - This study aimed to identify anatomical areas where resections of oral squamous cell carcinomas (OSCC) are significantly associated with close or positive margins....     

Does the Brown classification of maxillectomy defects have prognostic prediction for patients with oral cavity squamous cell carcinoma involving the maxilla?

The aim of this study was to investigate the correlation between the maxillectomy defect, T stage, and prognosis of patients with maxillary squamous cell carcinoma (SCC). The Brown classification system was used to appraise the maxillectomy defects due to maxillary SCC. The clinical data of 137 patients with maxillary SCC during the period 2000–2010 were reviewed; 105 patients were followed up. Preoperative T stage and postoperative maxillectomy class were recorded. The relationship between the maxillectomy defect class and T stage of maxillary SCC was analysed. Correlations between the maxillectomy defect class, local recurrence rate, and survival rate were assessed using IBM SPSS Statistics v19.0. The most common maxillectomy defect class was IIb (54.7%, 75/137). The maxillectomy defect class was significantly associated with the T stage (P < 0.001). Both T stage and the maxillectomy defect class were significantly associated with the survival rate of patients with maxillary SCC (both P <  0.001). In conclusion, the class of the maxillectomy defect was found to be associated with the T stage. Both of these were prognostic factors for patients with maxillary SCC. The class of the maxillectomy defect is suitable for clinical application in predicting the prognosis compared with T stage.     

Proliferative index activity in oral squamous cell carcinoma: indication for postoperative radiotherapy?

The predictive value of the Ki-67 labelling index and its relationship with radiosensitivity in oral squamous cell carcinoma (SCC) remains controversial. We sought to evaluate whether the expression of Ki-67 antigen found in SCC of the tongue and the floor of the mouth is an indication for postoperative radiotherapy (PORT). The first study group included 34 patients who were treated only with primary surgery, while the second group included 26 patients who underwent primary surgery combined with PORT. The correlation between Ki-67 expression and loco-regional recurrence, as well as the 5-year disease-specific survival, was assessed in the two groups. Cases of high-proliferative tumours showed a significantly higher risk of loco-regional recurrence (P = 0.018) and a poorer prognosis (P = 0.001) only in the 34 patients treated with surgery alone. In multivariate Cox regression analysis, high Ki-67 expression was an independent predictor of loco-regional recurrence (HR 5.42, P = 0.029) and disease-specific survival (HR 9.02, P = 0.004). The correlation between Ki-67 expression and the risk of loco-regional recurrence in SCC of the tongue and the floor of the mouth may be useful in the selection of patients at a higher risk of recurrence who would benefit from PORT, despite adequate margins of resection and early stage of the disease.     

Does the method of resection affect the margins of tumours in the oral cavity? Prospective controlled study in pigs

It is important to obtain tumour-free resection margins in patients with oral cancer. Pathological processing is known to cause tissue to shrink, which affects the reported margins, and it is postulated that the method of resection also has an effect. We marked standardised simulated lesions on the tongues of 15 live anaesthetised pigs and divided each lesion into four equal sections. They were resected each with a margin of 10 mm using cutting diathermy, coagulative diathermy, Harmonic scalpel, and a conventional scalpel. After processing, the excision margins were measured. With cutting diathermy and coagulative diathermy, shrinkage of the soft tissues was minimal relative to the margin of the simulated lesion compared with the Harmonic scalpel (p = 0.001) and conventional scalpel (p = 0.001). Cutting diathermy and coagulative diathermy caused significant thermal damage (p = 0.001). The method of resection affects the surgical margin. Diathermy resulted in thermal injury and denaturing of the underlying muscle, but there was less tissue contraction than when the Harmonic scalpel and conventional scalpel were used. The ethics committee approved the study, which was undertaken in a registered European Scientific Institute in Hamburg.     

Is there any benefit in surgery for potentially malignant disorders of the oral cavity?

Oral epithelial dysplasia grading is currently recognised as the most useful prognostic indicator for predicting conversion of potentially malignant disorders of the oral cavity to squamous cell carcinoma. It is also used as a basis for deciding management options. However, the diagnosis of oral epithelial dysplasia is subjective and thus unreliable. Surgery is currently recommended for removal of high‐risk lesions; however, the evidence for its success is lacking, and in some cases, there have been reports of increased recurrence of malignancy following surgical excision. Molecular and genetic markers have been identified and show promising results in identifying which potential malignant disorders are at risk of malignant transformation. The current evidence available for prognosis of potential malignant disorders and its treatment is based on observational and retrospective data. No randomised control trials have been conducted to date to assess the efficacy of surgery in oral epithelial dysplasia. Until good quality evidence is available from well‐designed randomised control trials, experts still recommend the surgical removal of potential malignant disorders which are regarded as high risk.     

Beta‐defensins: what are they REALLY doing in the oral cavity?

Initially identified as broad-spectrum antimicrobial peptides, the members of the β-defensin family have increasingly been observed to exhibit numerous other activities, both in vitro and in vivo, that do not always relate directly to host defense. Much research has been carried out in the oral cavity, where the presence of commensal bacteria further complicates the definition of their role. In addition to direct antimicrobial activity, β-defensins exhibit potent chemotactic activity for a variety of innate immune cells, as well as stimulating other cells to secrete cytokines. They can also inhibit the inflammatory response, however, by the specific binding of microbe-associated molecular patterns. These patterns are also able to induce the expression of β-defensins in gingival epithelial cells, although significant differences are observed between different species of bacteria. Together these results suggest a complex model of a host-defense related function in maintenance of bacterial homeostasis and response to pathogens. This model is complicated, however, by numerous other observations of β-defensin involvement in cell proliferation, wound healing and cancer. Together, the in vitro, in vivo and human studies suggest that these peptides are important in the biology of the oral cavity; exactly how is still subject to speculation.     

Epstein–Barr virus-positive mucocutaneous ulcer of the oral cavity in a patient who had had a renal transplant

The Epstein–Barr virus-positive mucocutaneous ulcer is a new phenomenon that was first described in 2014, and we know of only 67 reported cases. We describe a case in a patient who had had a renal transplant.     

Welcome the “new kid on the block” into the family: artificial intelligence in oral and maxillofacial surgery

Recent decades have witnessed the genesis and progressive application of intelligent machines and computer programs that have the ability to process information and execute cognitive functions similar to those of human logic and reasoning such as problem solving and decision making. That is artificial intelligence (AI) in a nutshell as envisioned by John McCarthy, “the father of AI”. Healthcare has welcomed AI, giving rise to collaborations such as the Moorfields Eye Hospital and Google’s DeepMind division in the screening and predicting of retinal disease. The use of AI by the maxillofacial surgical fraternity is, however, limited. We wish to highlight the fact that surgeons are uniquely positioned to help drive these innovations rather than passively waiting for the technology to become useful.