Nativity status and oral cancer survival in the United States: implications for dental clinical practice

OBJECTIVE

Nativity status is a major determinant of health and healthcare access in the United States. This study compared oral squamous cell carcinoma (OSCC) survival between US-born and foreign-born patients.

METHOD AND MATERIALS

Data were obtained from the 1988-2008 Surveillance, Epidemiology and End Results database. A Cox proportional hazards multivariate model was used to assess the eff ect of birthplace on OSCC survival, adjusting for other sociodemographic and clinical covariates.

RESULTS

US-born patients had a higher median survival time (19.3 years; 95% confidence interval [CI]: 18.6-19.7) compared to foreign-born patients (10.7 years; 95% CI: 10.1-11.3). After adjusting for other factors, being born in the US conferred a modest protective eff ect from OSCC mortality (hazard ratio [HR] = 0.93, 95% CI: 0.87- 0.99). Other factors that conferred better survival included involvement of paired structures (HR = 0.65; 95% CI: 0.58- 0.74), lip involvement rather than tongue lesions (HR = 0.76; 95% CI: 0.71-0.82), and receipt of either surgery (HR = 0.89; 95% CI: 0.84-0.94) or radiation therapy (HR = 0.92; 95% CI: 0.87-0.97).

CONCLUSION

US-born patients had significantly better OSCC survival compared to their foreign-born counterparts. This underscores the need for enhanced and sustained efforts to improve access to healthcare among immigrant populations. In addition, oral health professionals such as general dentists, oral pathologists, and oral surgeons providing care to immigrant patients should ensure that reasonable efforts are made to communicate effectively with patients with language barriers, especially in high-stake conditions such as cancer. This may help increase such patients' awareness of treatment provided and the critical issues regarding cancer care, resulting in enhanced treatment outcome.

[Rab23 enhances invasion of Sa3 cutaneous squamous cell carcinoma cells via up-regulating the expression of Rac1]

OBJECTIVE

To investigate the effect of Ras-related protein 23 (Rab23) on the invasion capacity of Sa3 cutaneous squamous cell carcinaoma (cSCC) cells and determine whether Rab23 can enhance the invasion of Sa3 cells through regulation of Ras-related C3 botulinum toxin substrate 1 (Rac1).

METHODS

Sa3 cells stably expressing exogenous Rab23 or Sa3 cells deprived of endogenous Rab23 were generated using lentivirus transfection. Transwell(TM) invasion assay was used to evaluate the invasion capacity in the above-mentioned cells. The effects of Rab23 overexpression or knockdown on Rac1 expression were assessed using Western blotting. In the last experimental setting, the engineered cells were pretreated with Rac1 inhibitor Z62954982 before being subjected to the assessment of invasion capacity by Transwell(TM) assay.

RESULTS

Rab23 overexpression enhanced the invasion ability, whereas ablation of Rab23 attenuated the invasion in Sa3 cells. Rab23 could up-regulate the expression level of Rac1. Finally, using Rac1 inhibitor, we successfully suppressed the invasion capacity of Sa3 cells stably overexpressing Rab23.

CONCLUSION

Rab23 may enhance cSCC cell invasion via up-regulating Rac1 signaling.

[Assessment of the quality of life of oral cancer patients after reconstruction with free anterolateral thigh perforator flaps]

OBJECTIVE

This study aims to evaluate the quality of life (QOL) of patients who underwent resection of oral cancer and reconstruction by free anierolateral thigh perforator flaps (ALTF).

METHODS

A total of 32 patients with oral and maxillofacial malignancies who had undergone the resection of oral cancer and reconstruction by ALTF were retrospectively analyzed. At 12 months postoperatively, the QOL of these patients was assessed by using the 14-item oral health impact profile (OHIP-14) and the medical outcome study short form-36 (SF-36) questionnaires.

RESULTS

A total of 32 questionnaires were collected. In SF-36, the highest scoring domains were bodily pain (78.58 ± 14.82), physical functioning (72.08 ± 27.86), and the role of physical (60.00 ± 42.63), whereas the lowest scoring domains were role-emotional (41.67 ± 39.62), followed by mental health (50.75 ± 13.07) and health transition (54.17 ± 21.75). In OHIP-14, the lowest scoring domains were social disability (34.50 ± 11.32) and handicap (36.04 ± 12.05), indicating the functional recovery was better; and the highest scoring domains were physical pain (73.50 ± 18.96) and psychological discomfort (60.17 ± 20.66), indicating the functional recovery was worse.

CONCLUSION

The ALTF is an ideal selection for the reconstruction of oral defects after cancer resection. In using this flap, the basic social need of patients after surgery can be satisfied. Moreover, the appearance and the functions of chewing, deglutition, and speech can be restored in varying degrees. Thus, ALTF can improve the patients' QOL.

Life expectancy and expected years of life lost to oral cancer in Taiwan: a nation-wide analysis of 22,024 cases followed for 10 years

OBJECTIVES

This analysis examined the life expectancies (LE) and expected years of life lost (EYLL) in relation to oral cancer in Taiwan.

MATERIALS AND METHODS

A semi-parametric extrapolation method was applied to estimate gender, age, histology, subsite, and stage stratified LE, EYLL of 22,024 pathologically verified oral cancer patients retrospectively recruited from the National Cancer Registry of Taiwan during 2002-2009, who were followed up to 2011.

RESULTS

The patients were predominantly male 20,101, (91.3%), and over 80% were less than 65years old. The mean age at diagnosis of males was younger than that of females (52.73years vs. 60.76years). The LE after diagnosis was longer among females than males (15.26years vs. 12.73years), with a smaller loss of the corresponding EYLL (8.88years vs. 14.05years), which prevails after stratification by age and stage. More than half of the oral cancer cases were diagnosed at a later stage, with 2921 cases (13.3%) of stage III and 8488 (38.5%) of stage IV. The five-year overall survival rate of oral cancer for stages I, II, III, and IV were 78.98%, 69.38%, 54.62%, and 36.17%, respectively. The earlier the diagnosis, the longer the life expectancy and the smaller the EYLL.

CONCLUSIONS

We concluded that early detection and early intervention of oral cancer can prolong life expectancy and reduce the years of life lost, indicating the importance of proactive screening and oral hygiene.

Evaluation of the Effects of Dental Implants on Oral Lesions

Objective

To determine whether dental implants impress oral lesions, and to evaluate the nature of their effect on the lesions.

Materials and methods

A comprehensive search was done via Google and PubMed for articles (including case reports and literature reviews) containing the keywords ‘oral squamous cell carcinoma’ (OSCC), ‘oral lichen planus’ (OLP), ‘lichenoid contact reaction’ (LCR), ‘osseointegrated implants’, and ‘dental implants’, in the last 10 years (2002-2012).

Results

The study included 24 articles involving patients with dental implants, and some oral lesions (e.g. oral lichen planus and oral squamous cell carcinoma) or with a history of lesions. In these publications, there is evidence suggesting the possibility of emergence, exacerbation, recurrence, or even malignant transformation of the oral lesions after implant placement in some cases.

Conclusion

Based on our review of the literature, implant treatment does not seem to be completely safe under any circumstances, but may have some complications in subjects with certain diseases (e.g. oral lesions, autoimmune diseases, malignancies, allergic reactions, etc.). Therefore prior to treatment, patients should be fully informed of the risks.

Clinical significance

Implant treatment is best done with caution in patients with cancer or mucocutaneous disorders.

How to cite this article

Agha-Hosseini F, Rohani B. Evaluation of the Effects of Dental Implants on Oral Lesions. J Contemp Dent Pract 2015;16(5):400-406.

Agrin and perlecan mediate tumorigenic processes in oral squamous cell carcinoma

Oral squamous cell carcinoma is the most common type of cancer in the oral cavity, representing more than 90% of all oral cancers. The characterization of altered molecules in oral cancer is essential to understand molecular mechanisms underlying tumor progression as well as to contribute to cancer biomarker and therapeutic target discovery. Proteoglycans are key molecular effectors of cell surface and pericellular microenvironments, performing multiple functions in cancer. Two of the major basement membrane proteoglycans, agrin and perlecan, were investigated in this study regarding their role in oral cancer. Using real time quantitative PCR (qRT-PCR), we showed that agrin and perlecan are highly expressed in oral squamous cell carcinoma. Interestingly, cell lines originated from distinct sites showed different expression of agrin and perlecan. Enzymatically targeting chondroitin sulfate modification by chondroitinase, oral squamous carcinoma cell line had a reduced ability to adhere to extracellular matrix proteins and increased sensibility to cisplatin. Additionally, knockdown of agrin and perlecan promoted a decrease on cell migration and adhesion, and on resistance of cells to cisplatin. Our study showed, for the first time, a negative regulation on oral cancer-associated events by either targeting chondroitin sulfate content or agrin and perlecan levels.

Clinical case of the month: a 22-year-old man with AIDS presenting with shortness of breath and an oral lesion

Since the development of combination antiretroviral therapy (cART), the incidence and mortality associated with Kaposi sarcoma (KS) have been reduced, although not eliminated. Clinical presentations of KS range from simple skin involvement to disseminated disease, including involvement of the oral cavity and viscera, which portends a more ominous prognosis. Multiple case reports and data from clinical trials indicate that administration of systemic corticosteroids may aggravate KS. We present a case of disseminated KS following administration of prednisone for presumed immune reconstitution inflammatory syndrome (IRIS) associated with fungal pneumonia in an HIV-infected individual. The discussion that follows outlines the pathophysiology and clinical presentations associated with KS and existing data for the role of corticosteroids in promoting KS progression.

[Nuclear translocation of epidermal growth factor receptor and its relation to clinicopathological factors in oral squamous cell carcinomas]

The epidermal growth factor receptor (EGFR) is one of the receptor tyrosine kinases. Some EGFRs are transferred from membrane to nucleus upon ligand binding and an increase of this translocation causes high-level expression of nuclear EGFR. The high-level expression of nuclear EGFR was reported to be a poor prognostic factor in various cancers such as breast cancer, ovarian cancer, gallbladder cancer, prostate cancer and oropharyngeal cancer. Regarding oral cancers, one report indicated that nuclear EGFR is detected in oral squamous cell carcinoma (OSCC) on immunohistochemical staining, but did not mention the clinicopathological prognostic value in detail. Therefore, we investigated the expression of nuclear EGFR in OSCC cell lines and primary tumor specimens of tongue SCCs to see whether nuclear EGFR could be a useful prognostic value. We verified the expression level of nuclear EGFR in OSCC cell lines and observed an increase in the amount of nuclear EGFR upon EGF stimulation with the expression level reaching its peak after 15 minutes. Nuclear EGFR positive tumors were found in 23 patients (28.0%) with tongue SCCs. However, we could not find any correlation between clinicopathological factors and the expression of nuclear EGFR in patients with tongue SCCs.

Cell proliferation and expression of connexins differ in melanotic and amelanotic canine oral melanomas

Melanoma is a malignant neoplasm occurring in several animal species, and is the most frequently found tumor in the oral cavity in dogs. Melanomas are classified into two types: melanotic and amelanotic. Prior research suggests that human amelanotic melanomas are more aggressive than their melanotic counterparts. This study evaluates the behavior of canine melanotic and amelanotic oral cavity melanomas and quantifies cell proliferation and the expression of connexins. Twenty-five melanomas (16 melanotic and 9 amelanotic) were collected from dogs during clinical procedures at the Veterinary Hospital of the School of Veterinary Medicine and Animal Science of the University of São Paulo, Brazil. After diagnosis, dogs were followed until death or euthanasia. Histopathology confirmed the gross melanotic or amelanotic characteristics and tumors were classified according to the WHO. HMB45 or Melan A immunostainings were performed to confirm the diagnosis of amelanotic melanomas. Cell proliferation was quantified both by counting mitotic figures and PCNA positive nuclei. Expressions of connexins 26 and 43 were evaluated by immunohistochemistry, qRT-PCR and Western blot. Dogs bearing amelanotic melanomas presented a shorter lifespan in comparison to those with melanotic melanomas. Cell proliferation was significantly higher in amelanotic melanomas. Expressions of Connexins 26 and 43 were significantly reduced in amelanotic melanomas. The results presented here suggest that oral cavity melanotic and amelanotic melanomas differ regarding their behavior, cell proliferation and connexin expression in dogs, indicating a higher aggressiveness of amelanotic variants.

Expression of angiopoietin-2 and vascular endothelial growth factor receptor-3 correlates with lymphangiogenesis and angiogenesis and affects survival of oral squamous cell carcinoma

Background

Both Ang-2 and VEGFR-3 are major regulators of angiogenesis and lymphangiogenesis, respectively, and thus may affect prognosis of OSCC. We sought to determine the associations between Ang-2 and VEGFR-3 expression and survival of OSCC.

Methods

Ang-2 and VEGFR-3 expression was determined immunohistochemically in tumor tissues from 112 patients with OSCC; OSCC-adjacent noncancerous oral tissue from 85 OSCC patients; and normal oral mucosa from 37 cancer-free individuals. A log-rank test and Cox proportional hazard models were used to compare survival among different groups with expression of Ang-2 and VEGFR-3.

Results

Ang-2 and VEGFR-3 expression was upregulated in OSCC compared to nontumor tissue (all P<0.05). High Ang-2 expression positively correlated with microvessel density (MVD) (P<0.01), and high VEGFR-3 expression positively correlated with lymph node metastasis (P<0.01) and lymphatic vessel density (LVD) (P<0.01). The patients with high expression of Ang-2 alone or in combination with VEGFR-3 had a significantly worse survival than in patients with low expression of Ang-2 or any other co-expression status (all P<0.05), respectively. Furthermore, multivariable analysis showed that patients with high expression of Ang-2 alone or in combination with VEGFR-3 had a significantly increased risk of death compared with those with low expression of Ang-2 or any other co-expression status (HR, 2.7, 95% CI, 1.1–6.2 and 5.0, 1.3–15.4, respectively).

Conclusions

These results suggest that increased expression in tumors of Ang-2 may individually, or in combination with VEGFR-3, predict poor prognosis of OSCC.

Functional assessment and rehabilitation: how to maximize outcomes

The number of oral cavity and oropharyngeal cancer survivors is rising. By 2030, oropharyngeal cancers are projected to account for almost half of all head and neck cancers. Normal speech, swallowing, and respiration can be disrupted by adverse effects of tumor and cancer therapy. This review summarizes clinically distinct functional outcomes of patients with oral cavity and oropharyngeal cancers, methods of pretreatment functional assessments, strategies to reduce or prevent functional complications, and posttreatment rehabilitation considerations.

Clinical presentation of oral squamous cell carcinoma

AIMS AND OBJECTIVES

This study aims to present the symptoms first observed by patients diagnosed of oral squamous cell carcinoma (OSCC) presenting at the University College Hospital, Ibadan between January 1990 and December 2008 as well as the time lag between the observation and presentation in the hospital.

PATIENTS AND METHODS

This is a retrospective review of patients that have been diagnosed histologically as squamous cell carcinoma of the oral cavity at the University College Hospital Ibadan, Nigeria between January 1990 and December 2008.

RESULTS

Painful tooth/teeth which are not mobile were the most common symptom in these patients (27.5%). However, about 59.4% of patients had painless symptoms at the onset of the disease. The interval between onset of symptoms and clinical presentation ranged from 3 weeks to 36 months with a mean duration of 7 ± 6.3 months. Paradoxically, patients that experienced painful symptoms at the onset of disease presented later than those who had painless symptoms

CONCLUSION

The first symptoms observed by these patients were not pathognomonic of oral cancer but are shared by several relatively more common oral diseases. Awareness of the populace about oral cancer should be increased as well as the index of suspicion of the medical practitioner for OSCC.

Abnormal expression of PI3K isoforms in patients with tobacco-related oral squamous cell carcinoma

BACKGROUND

The phosphatidylinositol 3-kinase (PI3K) signaling regulates several cellular functions such as motility, proliferation, angiogenesis and survival.

METHODS

Since there is no information on expression of PI3K isoforms in oral cancer, we studied the expression of different isoforms of PI3K (p110α, p110γ, PI3K-C2, Vps34p and p85α) in tumor samples and PBMC by RT and q-RTPCR and serum levels of PI3K p110α by SPR and ELISA techniques in 108 patients with tobacco-related oral squamous cell carcinoma (OSCC) and 46 normal subjects.

RESULTS

We observed significantly higher PI3K p110α (p<0.0001) and lower (p<0.0001) vesicular sorting protein 34p (Vps34p) mRNA both in PBMC and tissue samples of oral cancer patients as compared to the normal controls. Other PI3K isoforms did not show such change. Circulating PI3K p110α levels were higher in patients (p<0.0001) as compared to healthy subjects, the SPR data showed direct correlation with advancing stage of the disease. PI3K p110α was overexpressed in tumor samples but not in the normal buccal mucosa.

CONCLUSIONS

Upregulation of circulating PI3K p110α isoform and its direct correlation with increasing tumor load in OSCC patients indicates that it may be a significant prognostic indicator and a suitable target for therapeutic/chemo-preventive strategies for tobacco-related OSCC.

Progression of oral squamous cell carcinoma accompanied with reduced E-cadherin expression but not cadherin switch

The cadherin switch from E-cadherin to N-cadherin is considered as a hallmark of the epithelial-mesenchymal transition and progression of carcinomas. Although it enhances aggressive behaviors of adenocarcinoma cells, the significance and role of cadherin switch in squamous cell carcinomas (SCCs) are largely controversial. In the present study, we immunohistochemically examined expression of E-cadherin and N-cadherin in oral SCCs (n = 63) and its implications for the disease progression. The E-cadherin-positive carcinoma cells were rapidly decreased at the invasive front. The percentage of carcinoma cells stained E-cadherin at the cell membrane was reduced in parallel with tumor dedifferentiation (P<0.01) and enhanced invasion (P<0.01). In contrast, N-cadherin-positive cells were very limited and did not correlate with the clinicopathological parameters. Mouse tongue tumors xenotransplantated oral SCC cell lines expressing both cadherins in vitro reproduced the reduction of E-cadherin-positive carcinoma cells at the invasive front and the negligible expression of N-cadherin. These results demonstrate that the reduction of E-cadherin-mediated carcinoma cell-cell adhesion at the invasive front, but not the cadherin switch, is an important determinant for oral SCC progression, and suggest that the environments surrounding carcinoma cells largely affect the cadherin expression.

Histopathological changes in parotid and submandibular glands of patients treated with preoperative chemoradiation therapy for oral cancer

We retrospectively evaluated the relationship between computed tomography (CT)- and histopathological findings of parotid and submandibular glands in six patients treated for advanced oral cancer. Eligibility criteria were a pathologic diagnosis of oral squamous cell carcinoma, preoperative chemoradiation therapy (CRT) with a total dose of 30 Gy and oral S-1 (80 mg/m²/day), the availability of morphological assessments by CT and of functional assessments with the Saxon test before- and 2 weeks after CRT, and the availability of histopathological slides of irradiated parotid and submandibular glands. In the histopathological interpretation, gland structures were divided into acinar-, duct-, and adipose cells and other tissues. The Mann-Whitney test and the Spearman rank correlation test were used to determine histopathological changes. After 30-Gy irradiation, saliva production and parotid and submandibular volumes were significantly decreased (P < 0.05 each). Histopathological analysis demonstrated that 30-Gy irradiation resulted in a loss of acinar cells although acinar cells in the submandibular gland were relatively retained; the median acinar rate in the parotid and submandibular glands was 1.1% and 19.0%, respectively. The CT values after CRT were inversely correlated with adipose ratios (r = -0.98, P < 0.01) and there was a strong correlation between CT values before and after CRT (r = 0.97, P < 0.01). Our results suggested that acinar cell loss is a main contributor to changes in the volume and function of irradiated human parotid and submandibular glands. The CT value may reflect the adipose ratio rather than salivary function.

Characterization of Yemeni patients treated for oral and pharyngeal cancers in Saudi Arabia

OBJECTIVE

To determine the relative frequency and rank of oral cancer (OC) and pharyngeal cancer (PC) among Yemeni cancer patients who were treated and registered in the Kingdom of Saudi Arabia (KSA) over 14 years, and to characterize these patients by different grouping factors.

METHODS

In this retrospective study, the Saudi Cancer Registry, Riyadh, KSA officially provided the data regarding all Yemeni patients registered between 1994 and 2007. These data were reclassified and analyzed to present the cancer distribution by the main sites adopted by Globocan 2008. The OC and PC patients were statistically described and analyzed according to the demographic data and tumor details. This study was conducted at the Oral Medicine, Medically Compromised and Research Clinic, Department of Dentistry, Riyadh Military Hospital, Saudi Arabia between January and April 2011.

RESULTS

There were 5862 Yemenis registered with malignancies. The OC ranked the eighth most common malignancy (215, 3.7%) with 1.65:1 male to female ratio, whereas PC ranked the seventh (245, 4.2%) with 2.06:1 male to female ratio. The most affected oral sub-site was the tongue (91, 42.3%) while the nasopharynx accounted for 79% (194) of PC. The PC patients were significantly younger than those with OC (45.88+/-16.72 versus 55.6+/-15.75). The squamous cell carcinoma was the most frequent morphological type (289, 63.5%) but significantly more frequent in OC. Approximately 56% (255 patients) were diagnosed at advanced stage, however, significantly more frequent in PC (155, 64.6%).

CONCLUSION

The relative frequencies of oral and pharyngeal cancers in Yemen are quite high. The demographic and tumor characteristics of these cancers are obviously different.

5-lipoxygenase expression and tepoxalin-induced cell death in squamous cell carcinomas in cats

OBJECTIVE

To assess expression pattern and subcellular compartmentalization of 5-lipoxygenase in cutaneous, UV radiation-induced, and oral squamous cell carcinomas (SCCs) in cats and determine the effects of cyclooxygenase or 5-lipoxygenase inhibition on proliferation or apoptosis in a feline oral squamous cell carcinoma (SCCF1) cell line.

SAMPLE

60 archived paraffin-embedded samples of SCCs from 60 cats and SCCF1 cells.

PROCEDURES

Retrospective immunohistochemical analysis of the archived samples of SCCs (20 cutaneous, 20 UV radiation-induced, and 20 oral tumors) was performed. Cell culture proliferation assays involving SCCF1 cells were performed, and tepoxalin-induced apoptosis and signaling were examined via western blotting and annexin V staining.

RESULTS

Immunohistochemically, staining for 5-lipoxygenase was most frequently of greatest intensity in oral SCCs, whereas staining of cutaneous and UV radiation-induced lesions had less consistent 5-lipoxygenase expression. Exposure of SCCF1 cells to the 5-lipoxygenase inhibitor tepoxalin resulted in apoptosis; the effect appeared to be mediated via alteration of cell signaling rather than via suppression of lipid mediators that are typically produced as a result of 5-lipoxygenase activity.

CONCLUSIONS AND CLINICAL RELEVANCE

In cats, expression of 5-lipoxygenase in SCCs appeared to differ depending on tumor location. The influence of tepoxalin-induced 5-lipoxygenase inhibition on a 5-lipoxygenase-expressing cell line coupled with the notable expression of 5-lipoxygenase in oral SCCs suggested that 5-lipoxygenase inhibition may have therapeutic benefits in affected cats. Although the safety of tepoxalin in cats has yet to be investigated, 5-lipoxygenase inhibitors should be evaluated for use as a potential treatment for SCCs in that species.

Blood pressure and free flap oxygenation in head and neck cancer patients

CONCLUSION

This study suggests that although oxygen partial pressure in tissue (p(ti)O(2)) measurement is a feasible method for continuous postoperative monitoring of free flaps, low correlation between blood pressure (BP) and p(ti)O(2) might predict compromised overall outcome. Thus, it is of utmost importance to keep the BP optimal for adequate perfusion of re-anastomosed tissue transfers.

OBJECTIVE

Optimal BP is an important factor in assuring adequate blood flow in a free flap. Tissue oxygenation in free flaps as a postoperative monitoring target is in routine clinical use in some clinics. Correlation between p(ti)O(2) and systemic BP was investigated.

METHODS

Ten consecutive patients underwent resection of head and neck squamous cell carcinoma followed by microvascular reconstruction with a free microvascular flap. P(ti)O(2) of each flap was continuously monitored for 3 postoperative days with a polarographic measurement system. BP was measured invasively and continuously during the operation and during the first postoperative day at the intensive care unit. The correlation coefficient between p(ti)O(2) and BP was analysed.

RESULTS

The correlation coefficient between p(ti)O(2) and BP was relatively high in all patients with uneventful flap survival (r (mean) = 0.63, n = 5). In flaps with haemodynamic problems or compromised flap vitality the correlation appeared low (r(mean) = -0.02, n = 5).

Interleukin-23 receptor polymorphism as a risk factor for oral cancer susceptibility

BACKGROUND

The purpose of this study was to evaluate the influence of genetic polymorphisms of interleukin (IL)-23 and the IL-23 receptor (IL-23R) on the susceptibility to oral cancer.

METHODS

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to measure polymorphisms of these genes in 240 controls and 240 patients with oral cancer.

RESULTS

Individuals with at least 1 varied C allele of rs10889677 (IL-23R polymorphism) had a 1.553-fold risk (95% confidence interval [CI], 1.073-2.241) of developing oral cancer compared with patients with the wild-type A/A homozygote. Patients with oral cancer with at least 1 varied C allele of rs10889677 had a 1.931-fold risk of tumor lymph node metastasis compared with patients with the C/C homozygote.

CONCLUSION

The varied C allele of the IL-23R gene may be considered a factor contributing to increased susceptibility and may be a predictive factor for tumor lymph node metastasis in Taiwanese with oral cancer.

Nasal-type NK/T-cell lymphoma with palatal ulcer as the earliest clinical manifestation: a case report with literature review

Extranodal nasal natural killer (NK)/T-cell lymphoma is a very rare kind of lymphoma, Oral cavity involvement of extranodal natural killer/T-cell lymphoma, nasal type is extremely rare, and its clinicopathologic features are also poorly understood. Recently, we experienced an unusual case of Epstein-Barr virus-associated, extranodal NK/T-cell type with a unhealed palatal ulcer as the earliest clinical feature. It is a challenge for oral medicine specialists to make the early diagnosis for this special type of tumor.

Areca nut and betel quid chewing among South Asian immigrants to Western countries and its implications for oral cancer screening

The South Asian community is the largest and one of the fastest growing minority groups in Canada, according to the 2006 census. These immigrants bring to Canada talents and skills that can promote Canada's economy and cultural diversity, but they also bring lifestyle habits that may lead to serious health issues. Chewing areca nut and betel quid (paan, with and without tobacco) is a known risk factor for oral cancer. This habit is common in the Indo-Canadian population, as evidenced by its sales in local Indian markets and restaurants. In this article, we present an overview of the sociocultural beliefs, knowledge and practices regarding betel quid/areca nut chewing, and discuss its implications for oral cancer screening among this immigrant population.

Plasmablastic lymphoma of the oral cavity: a rapidly progressive lymphoma associated with HIV infection

Plasmablastic lymphoma of the oral cavity is a form of non-Hodgkin lymphoma (NHL) and was first described in 1997. We describe a case of plasmablastic lymphoma in an HIV-infected patient who presented with an expanding oral lesion and symptoms of a toothache. We review all cases of plasmablastic lymphoma that have been reported in the literature. Plasmablastic lymphoma is strongly associated with immunodeficiency, and most particularly, with HIV infection. The pathophysiological origin of plasmablastic lymphoma has not been fully characterised, but the presence of Epstein-Barr virus (EBV) has often been documented in biopsy specimens, supporting a role for EBV in the pathogenesis of this lymphoma. The differential diagnosis for an expanding oral lesion includes both infectious and malignant processes. Biopsy is essential for making a correct and prompt diagnosis. Treatment usually involves chemotherapy, but antiretroviral therapy may also have an important role. Infectious disease clinicians should be aware of this newly described and increasingly encountered lymphoma, since it is prominently associated with immunosuppression and may be mistaken for other entities.