Demographics and occurrence of oral and pharyngeal cancers. The outcomes, the trends, the challenge

Diagnostic efficiency of differentiating small cancerous and precancerous lesions using mucosal brush smears of the oral cavity--a prospective and blinded study

The aim of this study was to evaluate the diagnostic accuracy of oral brush biopsy to identify early malignancy. One hundred and eighty-six brush biopsies of suspicious mucosal lesions were obtained, haematoxilin and eosin (H&E)-stained and compared with the histology of conventional excision biopsies of the same site performed concomitantly. The sensitivity for identifying squamous cell carcinoma (SCC) was 88.5%. High-risk lesions including squamous intraepithelial neoplasia (SIN II, SIN III) and SCC were identified with a sensitivity of 86.4%, using a pap-analogous classification, which is considered to be carcinomatous, as well as moderate and severe dysplastic cells positive. Depending on the cytopathologic definition for malignancy and the tumour size, the test accuracy varied: Extending the cytopathologic criteria for malignancy by defining all dysplastic or malignant cytopathologic findings as positive, the sensitivity was increased to 95.2% at the expense of the specificity, which was reduced from 94.9% to 82.3%. Separately analysing SCCs of less than 20 mm, the sensitivity was reduced by 9.5% to 78%. Although small malignant lesions seem to be less reliable by the conventional oral brush biopsy, it is a useful screening instrument for early diagnosis of suspicious, epithelial lesions and could therefore contribute to improved cancer prognosis.

Early Diagnosis of Oral Cancer

Survival rates for oral cancer are very poor, at approximately 50% overall, and have not improved markedly in recent decades despite advances in therapeutic interventions. Detecting oral cancer at an early stage is believed to be the most effective means of reducing rates of death, morbidity and disfigurement from this disease. Tobacco and alcohol consumption and pre-malign lesions are the most common aetiological factors. The proportion of patients presenting with oral cancer at an advanced stage is troubling. Early diagnosis is the most effective way of reducing the individual burden of the disease, decreasing morbidity and mortality and improving quality of life. For early diagnosis, healthcare providers should perform oral cancer examinations as part of their patient care regime, and need to be knowledgeable about early signs of oral carcinoma. Oral cancer awareness among the public should also be improved.

Overexpression of activin A in oral squamous cell carcinoma: association with poor prognosis and tumor progression

BACKGROUND

Both activin A, a member of transforming growth factor beta superfamily, and its inhibitor follistatin have been shown to be overexpressed in various cancers. We examined the potential role of activin A and follistatin in tissue and blood samples from patients with oral squamous cell carcinoma.

METHODS

For activin A and follistatin, the expression of tissue samples from 92 patients was examined by immunohistochemical study, and the serum levels of blood samples from 111 patients and 91 healthy controls were measured by enzyme-linked immunosorbent assay.

RESULTS

We found that overexpression of immunohistochemically detected activin A was correlated with positive N stage, poor histological differentiation, and perineural invasion (P = 0.029, 0.002, and 0.014, respectively). In survival analyses, patients with oral squamous cell carcinoma, whose tumors overexpressed activin A, had a worse prognosis for overall survival and disease-free survival (P = 0.009 and 0.007). However, expression of follistatin in tumor was not correlated with overall survival or disease-free survival. Serum activin A and follistatin levels in 111 untreated patients were neither significantly different from those of 91 control samples nor associated with any clinicopathological manifestations. In vitro suppression of activin A expression in OC3 cells using specific interfering RNA-attenuated cell proliferation, migration, and invasiveness.

CONCLUSIONS

These findings suggest that activin A overexpression in oral squamous cell carcinomas is associated with patients' survival and may contribute to tumor progression and metastasis.

Histological Differentiation of Primary Oral Squamous Cell Carcinomas in an Area of Betel Quid Chewing Prevalence

OBJECTIVES: This study evaluated associations between the histological differentiation of oral squamous cell carcinoma and additional clinicopathological manifestations, adverse events after treatment, and the outcomes of patients in a region prevalent for betel quid chewing.

STUDY DESIGN: Case series with chart review.

SETTING: Tertiary referral center.

SUBJECTS AND METHODS: A total of 150 patients with primary oral squamous cell carcinomas who underwent surgery with or without adjuvant therapy were enrolled.

RESULTS: Well, moderate, and poorly differentiated oral squamous cell carcinomas were reported in 54 (36%), 84 (56%), and 12 (8%) patients, respectively. There were no significant differences among different histological differentiations in age, sex, tumor, node, metastasis stage, bone invasion, depth of invasion, and history of carcinogen exposure. However, we found significant associations between tumor histological differentiation and nodal metastasis ( P < 0.0001), extracapsular spread ( P = 0.002), and perineural invasion ( P < 0.0001). In the analysis of adverse events for survival during patient follow-up, oral squamous cell carcinomas with poor differentiation had a higher probability of developing neck recurrence ( P = 0.001) and distant metastasis ( P = 0.019), but not local recurrence or a second primary cancer. For survival analysis, univariate analysis showed that patient age, tumor stage, extracapsular spread, presence of perineural invasion, and tumor differentiation were significant factors. Multivariate analysis further demonstrated that poor differentiation ( P = 0.007) was still a statistically significant factor.

CONCLUSION: The current study demonstrates that poorer tumor histological classifications of oral squamous cell carcinoma are significantly associated with positive nodal status, extracapsular spread, perineural invasion of primary tumors, and the probability of developing neck recurrence and distant metastasis after treatment.

Effectiveness of a social marketing media campaign to reduce oral cancer racial disparities

OBJECTIVES

The purpose of this study was to provide a systematic evaluation of a theory-driven oral cancer awareness media campaign.

METHODS

We surveyed a cohort of residents in an intervention city (250) and a control city (250) immediately prior to and after the media campaign. Participants (125 black/African American and 125 white) in each city completed surveys at baseline and follow-up. Oral cancer campaign awareness was assessed in both cities, along with 4 hypothetical health campaigns. Oral cancer awareness, oral cancer exam awareness, intent to receive an oral cancer exam, interest in exam, and receipt of exam were also assessed in both cities, both at baseline and follow-up.

RESULTS

Intervention city residents showed a significant increase in recognition of the campaign, awareness of the oral cancer exam, and interest in getting an exam, while no significant changes in those topics were found for the control city. Blacks/African Americans in the intervention city were significantly more likely than whites to demonstrate increases in awareness of the campaign, oral cancer awareness, and interest in receiving an oral cancer exam.

CONCLUSIONS

A theory-driven media campaign was successful in increasing awareness of the oral cancer exam and interest in the exam among blacks/African Americans.

Making new meanings of being in the world after treatment for oral cancer

When the mouth is affected by cancer, difficulties in satisfying basic human needs such as eating, tasting, swallowing, and speaking might arise, and the existential significance of the mouth might become obvious. How does it feel to live with these difficulties? What does it mean to be a human being living with the consequences of oral cancer? Five patients with oral cancer were interviewed a median time of 4 years after the beginning of treatment. A hermeneutic research approach was used to understand, explain, and interpret the transcribed interviews and showed how the consequences of oral cancer affected the being-in-the-world of the participants in three ways: existing as oneself, existing in the eyes of others, and existing with others. Against the background of the philosophy of Martin Heidegger, these findings illuminate how essential the mouth is to a human being's identity and existence.

Vascular fractal dimension and total vascular area in the study of oral cancer

BACKGROUND

Microvessel quantification has been studied extensively as a factor reflecting angiogenesis in various malignant tumors. The aim of our study was to evaluate the vascular fractal dimension and the immunohistochemically positive total vascular area in oral cavity carcinomas in order to assess their potential value as factors reflecting angiogenesis.

METHODS

Histologic sections from 48 carcinomas and 17 nonmalignant mucosa specimens were evaluated by image analysis using fractal analysis software. Total vascular area was also quantified.

RESULTS

Carcinomas presented higher mean values of vascular fractal dimension and total vascular area compared to normal mucosa. The difference for the vascular fractal dimension was statistically significant.

CONCLUSIONS

This study provides evidence that vascular fractal dimension could be used as a reliable factor reflecting angiogenesis in oral squamous cell carcinoma and that there are several statistically significant correlations among total vascular area, vascular fractal dimension, nuclear size, and clinicopathologic factors.

The effect of combination anti-endothelial growth factor receptor and anti-vascular endothelial growth factor receptor 2 targeted therapy on lymph node metastasis: a study in an orthotopic nude mouse model of squamous cell carcinoma of the oral tongue

OBJECTIVE

To evaluate the therapeutic effect of treatment with a combination of the monoclonal antibodies to the vascular endothelial growth factor receptor (DC101) and the epidermal growth factor receptor (cetuximab) in an orthotopic nude mouse model of metastatic squamous cell carcinoma of the oral tongue (SCCOT).

DESIGN

In vivo study.

SETTING

A translational research laboratory at a comprehensive cancer center.

SUBJECTS

Male athymic nude mice aged 8 to 12 weeks.

INTERVENTION

To develop orthotopic nude mouse models of SCCOT, OSC-19 cells or luciferase (Luc)-expressing OSC-19-Luc and JMAR-Luc cells were injected into the tongues of nude mice. Animals were randomly divided into 4 groups: DC101 alone, cetuximab alone, DC101 plus cetuximab, or placebo, and all treatments were administered twice per week for 4 weeks. The in vivo antitumor activity was monitored noninvasively by bioluminescence imaging. Tumors were resected at necropsy, and immunohistochemical and immunofluorescent staining were performed.

MAIN OUTCOME MEASURES

Tumor size, bioluminescence, animal survival, and percentage of animals with lymph node metastasis.

RESULTS

At the conclusion of the treatment period, the mean tumor volumes in the cetuximab alone and the DC101 plus cetuximab groups had decreased significantly compared with those that received the placebo control (68% [P = .002] and 84% [P < .001], respectively). Significant effects of the treatment were also observed in bioluminescence imaging. Mice treated with DC101 plus cetuximab also lived longer and had a lower incidence of neck lymph node metastases compared with the control group (P = .003).

CONCLUSIONS

Treatment with DC101 plus cetuximab inhibited the growth of SCCOT and decreased the incidence of the neck lymph node metastases in vivo. These results suggest that this combination treatment may be an effective strategy against metastatic SCCOT and warrants further preclinical trials.

Oral cancer: a prosthodontic diagnosis

The prosthodontic literature is replete with articles addressing the reconstruction, psychological adaptation, prosthesis success, quality of life, need for careful follow-up, and many other issues related to the patient who has undergone surgery, radiation, and/or chemotherapy for oral malignant neoplasms. However, in the prosthodontic professional literature, there is a paucity of information related to the early diagnosis and referral of lesions that may represent premalignant or malignant neoplasia. This article will describe the rationale, epidemiology, and appearance of oral premalignant and malignant mucosal lesions as well as the state-of-the-art diagnostic tools currently available to prosthodontists to ensure that their patients are diagnosed at the earliest possible time.

Primary malignant tumors of orofacial origin in Iran

Orofacial malignant tumors are the sixth most common malignancy in the world and, with pharyngeal malignancies, the third most common one in the developing world. This study was carried out to determine the malignant oral primary tumors in Shiraz, southern Iran. From April 2002 to March 2007, all (181) malignant tumors of the orofacial region recorded in Fars Cancer Registry Center of Shiraz University of Medical Sciences in Shiraz, southern Iran, were enrolled. Age range of patients was 4 to 91 years (53.7 +/- 18.6 years), whereas 40% of cases were older than 60 years. Ninety percent were epithelial tumors, 6% sarcomas, and 4% lymphomas. The most common sites were tongue (34.3%) and major salivary glands (32.5%). Squamous cell carcinoma (50.8%) was the most common malignant orofacial tumor. Oral malignant tumors were more common in males than females with an older aged preponderance. The tongue was the most commonly affected site, and squamous cell carcinoma was the most common malignant orofacial tumor. There is an urgent need for a national program focusing on early detection of these tumors. Oral health professionals in Iran should be educated on oral cavity comprehensive examination because of the important role of dentists in early detection of malignant oral tumors.

Is dental care utilization associated with oral cavity cancer in a large sample of community-based United States residents?

OBJECTIVES

Cancer of the oral cavity and pharynx remains one of the 10 leading causes of cancer deaths in US. Besides smoking and alcohol consumption, there are no well-established risk factors. While poor dental care had been implicated, it is unknown if lack of dental care, implying poor dental hygiene predisposes to oral cavity cancer. This study aimed to assess the relationship between dental care utilization during the past 12 months and the prevalence of oral cavity cancer.

METHODS

A cross-sectional design of the National Health Interview Survey of Adult, noninstitutionalized US residents (n=30 475) was used to assess the association between dental care utilization and self-reported diagnosis of oral cavity cancer. Chi-square statistic was used to examine the crude association between the explanatory variable, dental care utilization and other covariates, while unconditional logistic regression was used to assess the relationship between oral cavity cancer and dental care utilization.

RESULTS

There were statistically significant differences between those who utilized dental care during the past 12 months and those who did not with respect to education, income, age, marital status, and gender (P<0.05), but not health insurance coverage (P=0.53). In addition, those who utilized dental care relative to those who did not were 65% less likely to present with oral cavity cancer, prevalence odds ratio (POR), 0.35, 95% confidence interval (CI), 0.12-0.98. Further, higher income, advanced age, people of African heritage, and unmarried status were statistically significantly associated with oral cavity cancer (P<0.05), but health insurance coverage, alcohol use, and smoking were not, P>0.05. After simultaneously controlling for the relevant covariates, the association between dental care and oral cavity cancer did persist but imprecise. Thus, when compared with those who did not use dental care, those who did were 62% less likely to be diagnosed with oral cavity cancer, adjusted POR, 0.38, 95% CI, and 0.13-1.10.

CONCLUSIONS

Among US adults residing in community settings, use of dental care during the past 12 months was marginally statistically significantly associated with oral cavity cancer, but clinically relevant in assessing oral cavity cancer prevalence in this sample. However, because of the nature of our data, which restricts temporal sequence, a large sample prospective study that may identify modifiable factors associated with oral cavity cancer development, namely poor dental care is needed.

IKKalpha, a critical regulator of epidermal differentiation and a suppressor of skin cancer

IκB kinase α (IKKα), one of the two catalytic subunits of the IKK complex involved in nuclear factor κB (NF-κB) activation, also functions as a molecular switch that controls epidermal differentiation. This unexpected function requires IKKα nuclear translocation but does not depend on its kinase activity, and is independent of NF-κB signalling. Ikkα^–/– mice present with a hyperproliferative and undifferentiated epidermis characterized by complete absence of a granular layer and stratum corneum. Ikkα-deficient keratinocytes do not express terminal differentiation markers and continue to proliferate even when subjected to differentiation-inducing stimuli. This antiproliferative function of IKKα is also important for the suppression of squamous cell carcinogenesis. The exact mechanisms by which nuclear IKKα controls keratinocyte proliferation and differentiation remained mysterious for some time. Recent studies, however, have revealed that IKKα is a major cofactor in a TGFβ–Smad2/3 signalling pathway that is Smad4 independent. This pathway controls cell cycle withdrawal during keratinocyte terminal differentiation. Although these are not the only functions of nuclear IKKα, this multifunctional protein is a key regulator of keratinocyte and epidermal differentiation and a critical suppressor of skin cancer.

Detection of LINE-1s hypomethylation in oral rinses of oral squamous cell carcinoma patients

This study aimed to (i) investigate long interspersed nuclear element-1 (LINE-1) methylation levels of oral squamous cell carcinomas (OSCCs), the major type of oral malignancies; and (ii) investigate whether the hypomethylation of LINE-1s can be detected in oral rinses of OSCC patients. The combined bisulfite restriction analysis polymerase chain reaction (PCR) of LINE-1s (COBRALINE-1) was used. We found that tissues from OSCC specimens had lower methylation levels of LINE-1s than cells collected from the oral rinses of normal volunteers. Interestingly, cells collected from oral rinses of OSCC patients also revealed hypomethylated LINE-1s at the same level as OSCC tissues. There was no difference in the level of hypomethylation due to stages, locations, histological grades, and history of betel chewing, smoking and/or alcohol consumption. In conclusion, OSCCs possessed global hypomethylation and this alteration could be detected from oral rinses of OSCC patients by a simple PCR technique, COBRALINE-1. Therefore, COBRALINE-1 of oral rinses may be applied for non-invasive detection of oral malignancies.

Expression profile of the S100 gene family members in oral squamous cell carcinomas

BACKGROUND

Several of the S100 gene members have been reported to be differentially expressed in many human pathological conditions, in particular, the malignancies. Identification and quantification of the differentially expressed S100 gene members in oral squamous cell carcinoma (OSCC) might facilitate their use as potential diagnostic and/or prognostic markers or targets for therapy.

METHODS

we examined the expression profile of 16 members of the S100 gene family at the mRNA level by semiquantitative reverse transcription-polymerase chain reaction (sRT-PCR) in 27 cases of OSCCs/their pair-wised normal controls obtained from Sudanese patients, and confirmed the sRT-PCR results by performing quantitative real time-polymerase chain reaction (qRT-PCR) for 6 of the 16 genes examined.

RESULTS

With sRT-PCR, 4 (25%; S100A4, S100A6, S100A8, S100A14) out of the 16 S100 gene members examined were found to be significantly down-regulated (P < 0.05) in the tumors compared to the normal controls. None of the S100 gene members examined were found to be significantly up-regulated in the tumors. qRT-PCR results confirmed the significant down-regulation of the S100A4, S100A6, and S100A14 genes in the tumors examined.

CONCLUSION

S100 gene family members might play an important role in the pathogenesis of the OSCCs examined. Findings of the present work warrant in-depth studies of the S100 gene family members, in particular, the S100A4, S100A6, S100A8, and S100A14 to further understand their possible role(s) in OSCC tumorigenesis.

Genetic association of cytokine DNA polymorphisms with head and neck cancer

Mutations in oncogenes or tumor suppressor genes, as well as environmental factors such as tobacco chewing or smoking, poor oral hygiene, ill-fitting dental appliances, infection by certain HPV types, or alcohol abuse, seem to be involved in the multifactorial process of carcinogenesis in head and neck. Recently, several genetic association studies have indicated that common DNA polymorphisms in low penetrance genes may affect the susceptibility of an individual to malignancy. Cytokines are an important group of proteins that regulate and mediate inflammation and angiogenesis. Tumor growth, invasion and metastasis are facilitated when there is a deregulation in their production. Cytokines include interleukins (ILs), tumor necrosis factors (TNFs) and certain growth factors (GFs). A number of genetic association studies have recently investigated the putative correlation between functional DNA polymorphisms in cytokine genes and head and neck carcinomas. This review discusses the findings of such studies in oral, nasopharyngeal and esophageal squamous cell carcinomas. Extensive research has indicated that functional polymorphisms affecting gene expression of IL-4,-6,-8,-10 as well as TNF-alpha are strongly associated with increased risk for oral cancer. Gene expression of TNF-alpha seems to be associated also with esophageal carcinomas, while for nasopharyngeal cancer the picture is yet unclear. It is generally believed that such genetic association studies will gradually increase our knowledge regarding the predisposed manifestation and advancement of these malignancies in the head and neck region.

Differential roles of p16INK4A and p14ARF genes in prognosis of oral carcinoma

BACKGROUND

Oral cancer patients are found to have poor clinical outcome and high disease recurrence rate, in spite of an aggressive treatment regimen. The inactivation of INK4A/ARF loci is reported to be second to p53 inactivation in human cancers. The purpose of this study was to assess the prognostic significance of the molecular aberrations in the INK4A locus for effective identification of aggressive oral carcinoma cases needing alternate therapy.

MATERIALS AND METHODS

The study composed of 116 patients freshly diagnosed with oral carcinoma. The genetic and epigenetic status of the p16(INK4A) and p14(ARF) genes was evaluated. The relation between these genic alterations and different treatment end points, such as residual disease (initial response), disease recurrence, and overall survival, along with the standard clinical markers, were analyzed.

RESULTS

62% of the study cases had p16(INK4A) gene abnormalities, with deletion accounting for 33% and methylation for 29%. Alterations in p14(ARF) gene either by deletion (12%) and/or methylation (18%) were observed in 30% of the cases. p16(INK4A) deletion was associated with aggressive tumors, as evidenced by the nodal involvement of the disease. Low or absence of p16(INK4A) protein adversely affected the initial treatment response. Promoter methylation of p16(INK4A) was associated with increased disease recurrence and acts as an independent predictor for worse prognosis. Surprisingly, p14(ARF) methylation associated with lower recurrence rate in oral cancer patients with a good clinical outcome. Overall survival of these patients was associated with tumor size, nodal disease, and p16(INK4A) protein expression pattern. Our results indicate that p16(INK4A) and p14(ARF) alterations constitute a major molecular abnormality in oral cancer cases.

CONCLUSION

The molecular profile of INK4A/ARF locus, both at DNA and protein level, could be used as a prognostic biomarker for assessing the aggressiveness of disease in oral carcinoma patients. The study further shows the opposing clinical effect of these two genes, transcribed from the same locus, in oral cancer patients.

Genetic and environmental factors in head and neck cancer genesis

Head and neck squamous cell carcinoma (HNSCC) include squamous cell carcinomas of the oral cavity, pharynx, and larynx. Epidemiologic data suggest that the etiology and pathogenesis of HNSCC are influenced by environmental and lifestyle-related factors, such as tobacco use, ethanol consumption, papilloma virus infection, dietary factors and exposure to toxic substances. DNA repair systems and carcinogen-metabolizing enzymes can increase the risk for HNSCC but no definite causal mechanism has been demonstrated. There are several well-characterized entities that are associated with risk and prognosis of head and neck cancer, including Lynch-II syndrome, Bloom syndrome, Fanconi's anemia, xeroderma pigmentosum, ataxia telangiectasia, and Li-Fraumeni syndrome. This review aims to present the current status in our understanding of HNSCC and highlight controversies relating to the role of several factors in the genesis of the cancer.

Analysis of oral cancer epidemiology in the US reveals state-specific trends: implications for oral cancer prevention

Background

Downward trends have been observed in oral cancer incidence and mortality in the US over the past 30 years; however, these declines are not uniform within this population. Several studies have now demonstrated an increase in the incidence and mortality from oral cancers among certain demographic groups, which may have resulted from increased risks or risk behaviors. This study examines the underlying data that comprise these trends, to identify specific populations that may be at greater risk for morbidity and mortality from oral cancers.

Methods

Oral cancer incidence and mortality data analyzed for this study were generated using the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program.

Results

While oral cancer incidence and mortality rates have been declining over the past thirty years, these declines have reversed in the past five years among some demographic groups, including black females and white males. Sorting of these data by state revealed that eight states exhibited increasing rates of oral cancer deaths, Nevada, North Carolina, Iowa, Ohio, Maine, Idaho, North Dakota, and Wyoming, in stark contrast to the national downward trend. Furthermore, a detailed analysis of data from these states revealed increasing rates of oral cancer among older white males, also contrary to the overall trends observed at the national level.

Conclusion

These results signify that, despite the declining long-term trends in oral cancer incidence and mortality nationally, localized geographic areas exist where the incidence and mortality from oral cancers have been increasing. These areas represent sites where public health education and prevention efforts may be focused to target these specific populations in an effort to improve health outcomes and reduce disparities within these populations.

An altered fibronectin matrix induces anoikis of human squamous cell carcinoma cells by suppressing integrin alpha v levels and phosphorylation of FAK and ERK

Fibronectin regulates many cellular processes, including migration, proliferation, differentiation, and survival. Previously, we showed that squamous cell carcinoma (SCC) cell aggregates escape suspension-induced, p53-mediated anoikis by engaging in fibronectin-mediated survival signals through focal adhesion kinase (FAK). Here we report that an altered matrix, consisting of a mutated, nonfunctional high-affinity heparin-binding domain and the V region of fibronectin (V+H-), induced anoikis in human SCC cells; this response was blocked by inhibitors of caspase-8 and caspase-3. Anoikis was mediated by downregulation of integrin alpha v in a panel of SCC cells and was shown to be proteasome-dependent. Overexpression of integrin alpha v or FAK inhibited the increase in caspase-3 activation and apoptosis, whereas suppression of alpha v or FAK triggered a further significant increase in apoptosis, indicating that the apoptosis was mediated by suppression of integrin alpha v levels and dephosphorylation of FAK. Treatment with V+H- decreased the phosphorylation of extracellular signal-regulated kinase (ERK) 1 and 2, and direct activation of ERK by constitutively active MEK1, an ERK kinase, increased ERK1 and ERK2 phosphorylation and inhibited the increase in apoptosis induced by V+H-. ERK acted downstream from alpha v and FAK signals, since alpha v and FAK overexpression inhibited both the decrease in ERK phosphorylation and the increase in anoikis triggered by V+H-. These findings provide evidence that mutations in the high-affinity heparin-binding domain in association with the V region of fibronectin, or altered fibronectin matrices, induce anoikis in human SCC cells by modulating integrin alpha v-mediated phosphorylation of FAK and ERK.

The hamster model of sequential oral oncogenesis

Oral squamous cell carcinoma (OSCC) is a common cancer characterised by low survival rate and poor prognosis. The multistep process of oral carcinogenesis is affected by multiple genetic events such as alterations of oncogenes and tumour suppressor genes. The use of appropriate experimental animal models that accurately represent the cellular and molecular changes which are associated with the initiation and progression of human oral cancer is of crucial importance. The Syrian golden hamster cheek pouch oral carcinogenesis model is the best known animal system that closely correlates events involved in the development of premalignant and malignant human oral cancers. Therefore, we established an experimental system of chemically induced oral carcinogenesis in hamsters, in order to study different stages of tumour formation: normal mucosa, hyperkeratosis, hyperplasia, dysplasia, early invasion, well differentiated OSCC and moderately differentiated OSCC. We investigated the expression of oncogenes EGFR, erbB2, erbB3, FGFR-2, FGFR-3, c-myc, N-ras, ets-1, H-ras, c-fos and c-jun, apoptosis markers Bax and Bcl-2, tumour suppressor genes p53 and p16, and cell proliferation marker Ki-67 in the sequential stages of hamster oral oncogenesis. Here, we describe the findings of the experimental model in regard to the involvement of signal transduction pathways in every stage of cancer development. Increased apoptosis and cell proliferation were observed in early stages of oral oncogenesis. Furthermore, the increased expression of transmembrane receptors (EGFR, erbB2, FGFR-2 and FGFR-3) as well as the increased expression of nuclear transcriptional factors in early stages of oral cancer indicates that these molecules may be used as early prognostic factors for the progression of OSCC. Since the expression of both H-ras and N-ras do not seem to affect signal transduction during oral oncogenesis, it can be assumed that a different signalling pathway, such as the PI3K and/or PLCgamma pathway, may be implicated in the pathogenesis of OSCC.

Analysis of oral lesion biopsies identified and evaluated by visual examination, chemiluminescence and toluidine blue

Conventional visual examination and palpation remains the gold-standard for the identification of oral mucosal lesions. The purpose of this study was to investigate the adjunctive value of a chemiluminescent light source (ViziLite, Zila Pharmaceuticals, Phoenix, Arizona) and application of pharmaceutical grade toluidine blue (TBlue(630), Zila Pharmaceuticals, Phoenix, Arizona) to further assess lesions identified during the conventional oral soft tissue examination. Lesions deemed clinically suspicious by visual examination under incandescent light were further assessed under chemiluminescence and then application of toluidine blue stain. Differences between the conventional visual examination and chemiluminescent examination were noted on four characteristics which may aid in lesion identification. Tissue retention of toluidine blue stain was documented. Each suspicious lesion was biopsied and diagnosed based upon routine histopathology. Both adjunctive exams were evaluated by comparing the histologic diagnosis. The additive value of toluidine blue stain retention was assessed in lesions diagnosed as "serious pathology" defined as severe dysplasia, carcinoma in situ and squamous cell carcinoma. Ninety-seven clinically suspicious lesions in 84 patients were identified. The chemiluminescent exam improved the brightness and/or sharpness of margin in 61.8% of identified lesions. Biopsied lesions with toluidine blue stain retention reduced the false positive rate by 55.26% while maintaining a 100% negative predictive value (NPV). Chemiluminescence was shown to increase the brightness and margins of mucosal lesions in a majority of cases and therefore may assist in identification of mucosal lesions not considered under traditional visual examination. Toluidine blue stain retention was associated with a large reduction in biopsies showing benign histology (false positive biopsy results), while maintaining a 100% NPV for the presence of severe dysplasia or cancer. Practitioners may consider use of these adjuncts in practice, however the results presented are based upon experienced providers in referral centers for mucosal disease or cancer centers and therefore positive findings may be an indication for referral to experienced providers.

H-Ras mutation modulates the expression of major cell cycle regulatory proteins and disease prognosis in oral carcinoma

Activating mutations of the Ras is a moderately frequent event in oral carcinogenesis in Indian patients. Ras pathway has essential roles in regulation of various phases of the cell cycle, especially at G1 phase. Despite a large body of in vitro evidence, the multidimensional interaction between mutated Ras pathway and G1 cell cycle regulatory proteins in tumours in vivo is poorly determined. In the present study, DNA samples were screened for mutations in hot spot exons of B-Raf and hot spot codons 12, 13 and 61 of H-, K- and N-Ras by PCR-SSCP. Mutations were confirmed by direct sequencing. Expression of G1 cell cycle regulatory proteins-cyclin D1, CDK4, Rb, p53, p16 and p21 and proliferation marker PCNA was analysed immunohistochemically. The results revealed the absence of B-Raf mutations in oral carcinoma in spite of 12.5% of the samples showing H-Ras mutation. The H-Ras mutant cases showed significantly low cyclin D1 (P=0.027) and CDK4 (P=0.046) expression and overexpression of Rb (P=0.011) and p16 (P=0.026). H-Ras mutant carriers also had significantly high recurrence-free survival (P=0.033). In summary the present study demonstrated an epistatic interaction between H-Ras mutation and G1 cell cycle regulatory proteins in vivo. H-Ras mutation, thus, defines a molecular subtype of oral carcinoma with favourable outcome and unique biology.

Überlebensverbesserung eines unizentrischen Gesamtkollektivs aus 20 Jahren

PURPOSE

The development of overall survival of a DOSAK (German-Austrian-Swiss Cooperative Group on tumours of the maxillofacial region) clinic's overall population comprising a time period of more than 20 years (1983-2004) should be assessed. At a cutoff date (January 1st, 1997), a change from a primarily surgically based to a consequent multi-modality treatment regimen was implemented. The periods of time before and after that change should be compared.

METHODS AND PATIENTS

The data of the DOSAK registry entries on 1038 patients suffering from primary untreated oral and oropharyngeal carcinomas were updated with respect to follow-up and mortality data to achieve a 100% quality of follow-up. The end point (death) was reached in 67% of the overall population. Statistical analysis was carried out by the Trium Analysis Online corporation, Munich.

RESULTS

The portion of female and older tumor patients increased, more than half of all tumor patients were clearly in stage IV of the disease at first referral. The portion of patients operated on persisted approximately (80%), the portion of additional treatment modalities could be increased considerably. The fact of a bony infiltration by the tumor and the operability remained highly significantly relevant for survival in multivariate analysis, despite of multi-modality treatment. The survival rate of the patients remained significantly dependent on the clinical stage of the disease in multivariate analysis but could be improved by 10% in the clinical stages II and III and in the patients who could not be operated on. All in all, the cutoff date was statistically relevant for survival in multivariate analysis, i.[Symbol: see text]e. the change in the treatment regimen had a verifiable positive effect on the survival of a unicentric overall population.

CONCLUSION

Survival improvement in an overall population via change in treatment strategy is possible in relatively short time; the clinical stages II and III and the non-operable patients have the greatest benefit from a multi-modality treatment.

Metastasis of squamous cell carcinoma of the oral tongue

Squamous cell carcinoma of the oral tongue (SCCOT) is one of the most prevalent tumors of the head and neck region. Despite advances in treatment, the survival of patients with SCCOT has not significantly improved over the past several decades. Most frequently, treatment failure takes the form of local and regional recurrences, but as disease control in these areas improves, SCCOT treatment failures are occurring more often as distant metastasis. The presence of cervical lymph node metastasis is the most reliable adverse prognostic factor in patients with SCCOT, and extracapsular spread (ECS) of cervical lymph nodes metastasis is a particularly reliable predictor of regional and distant recurrence and death from disease. Decisions regarding the elective and therapeutic management of cervical lymph node metastases are made mainly on clinical grounds as we cannot always predict cervical lymph node metastasis from the size and extent of invasion of the primary tumors. Therefore, the treatment of these metastases in the management of SCCOT remains controversial. The promise of basing treatment decisions on biomarkers has yet to be fully realized because of our poor understanding of the mechanisms of regional and distant metastases of SCCOT. Here we summarize the current status of investigations of SCCOT metastases and the potential of these studies to have a positive impact on the clinical management of SCCOT in the future.

Nuclear fractal dimension as a prognostic factor in oral squamous cell carcinoma

Strong theoretical reasons exist for using fractal geometry in measurements of natural objects, including most objects studied in pathology. Indeed, fractal dimension provides a more precise and theoretically more appropriate approximation of their structure properties and especially their shape complexity. The aim of our study was to evaluate the nuclear fractal dimension (FD) in tissue specimens from patients with oral cavity carcinomas in order to assess its potential value as prognostic factor. Relationships between FD and other factors including clinicopathologic characteristics were also investigated. Histological sections from 48 oral squamous cell carcinomas as well as from 17 non-malignant mucosa specimens were stained with Hematoxylin-Eosin for pathological examination and with Feulgen for nuclear complexity evaluation. The sections were evaluated by image analysis using fractal analysis software to quantify nuclear FD by the box-counting method. Carcinomas presented higher mean values of FD compared to normal mucosa. Well differentiated neoplasms had lower FD values than poorly differentiated ones. FD was significantly correlated with the nuclear size. Patients with FD lower than the median value of the sample had statistically significant higher survival rates. Within the sample of patients studied, FD was proved to be an independent prognostic factor of survival in oral cancer patients. In addition this study provides evidence that there are several statistically significant correlations between FD and other morphometric characteristics or clinicopathologic factors in oral squamous cell carcinomas.

Oral cancer

Five percent of all tumors occur in the head and neck, and approximately half of those occur specifically in the oral cavity. Of the 615,000 new cases of head and neck [corrected] tumors reported worldwide in 2000, 300,000 were primary oral cavity squamous cell carcinomas. Recent data from the Surveillance, Epidemiology, and End Results Program suggest that 28,900 new cases of oral cancer will be identified and 7400 deaths attributed to oral cancer each year in the United States. The sixth leading cause of cancer-related mortality, oral cancer accounts for 1 death every hour in the United States. However, despite advances in screening tools, imaging technology, and access to primary care physicians, a considerable percentage of patients present with advanced-stage disease. Clinical signs and symptoms of head and neck tumors are often nonspecific and may be mistaken for other common ailments. Primary care physicians must be aware of the possibility of oral cancer, particularly the increasing incidence in young patients without traditional risk factors of alcohol and tobacco abuse. To improve survival, all patients should be routinely and vigilantly screened for oral mucosal lesions.

Prognostic factors associated with the survival of oral and pharyngeal carcinoma in Taiwan

Background

In Taiwan, a distinct ethnic group variation in incidence and mortality rates has been suggested for most carcinomas. Our aim is to identify the role of prognostic factors associated with the survival of oral and pharyngeal carcinoma in Taiwan.

Methods

Taiwan Cancer Registry records of 9039 subjects diagnosed with oral and pharyngeal carcinoma were analyzed. The population was divided into three ethnic groups by residence, which were Taiwanese aborigines, Hakka and Hokkien communities. Five-year survival rates were estimated by Kaplan-Meier methods. Ethnic curves differed significantly by log-rank test; therefore separate models for Taiwanese aborigines, Hakka and Hokkien were carried out. The Cox multivariate proportional hazards model was used to examine the role of prognostic factors on ethnic survival.

Results

The five-year survival rates of oral and pharyngeal carcinoma were significantly poorer for Hokkien community (53.9%) and Taiwanese aborigines community (58.1%) compared with Hakka community (60.5%). The adjusted hazard ratio of Taiwanese aborigines versus Hakka was 1.07 (95%CI, 0.86–1.33) for oral and pharyngeal carcinoma mortality, and 1.16 (95%CI, 1.01–1.33) for Hokkien versus Hakka. Males had significantly poor prognosis than females. Subjects with tongue and/or mouth carcinoma presented the worst prognosis, whereas lip carcinoma had the best prognosis. Subjects with verrucous carcinoma had better survival than squamous cell carcinoma. Prognosis was the worst in elderly subjects, and subjects who underwent surgery had the highest survival rate.

Conclusion

Our study presented that predictive variables in oral and pharyngeal carcinoma survival have been: ethnic groups, period of diagnosis, gender, diagnostic age, anatomic site, morphologic type, and therapy.

Promoter polymorphisms of DNMT3B and the risk of head and neck squamous cell carcinoma in Taiwan: a case-control study

Three single nucleotide polymorphisms (SNPs) of the DNMT3B promoter region, C46359T (-149C>T), -283T>C, and -579G>T might be a cancer susceptible factor for several cancers. In this study, we genotyped 226 head-and-neck squamous-cell carcinoma (HNSCC) patients and 249 controls to examine the association between three SNPs of the DNMT3B promoter and the associated risk of the development and/or metastasizing tendency of HNSCC for the population of Taiwan. We observed that only the T/T genotype (C46359T) was found to be present in both patient and control groups (100% frequency). The alleles frequency of -283CC, -283CT and -283TT among patients and controls was, respectively, 88.1% versus 84.3%, 11.9% versus 15.3%, and 0% versus 0.4%. The allele -597GG was not found in both groups, whereas the allele frequency of -597TT and -597GT for patients and controls was, respectively, 88.1% versus 85.5%, and 11.9% versus 14.5%. For both DNMT3B SNPs, inter-group comparison of the allele frequency between patients and controls and distribution of SNPs among cancer patients either featuring or not featuring cervical metastasis did not reveal any significant difference. In conclusion, the relative distribution of three DNMT3B SNPs among a Taiwanese population can not be used as a stratification marker to predict either an individual's susceptibility to HNSCC and/or the likelihood of cervical metastasis of HNSCC.

Diabetes may increase risk for oral cancer through the insulin receptor substrate-1 and focal adhesion kinase pathway

In light of recent epidemiological studies that associate diabetes mellitus with increased risk for oral cancer, we investigated in diabetic (type I) and normal rats with induced oral squamous cell carcinoma whether the molecular basis for that putative association involves insulin receptor substrate-1 (IRS-1) and focal adhesion kinase (FAK). Fourteen diabetic and 12 normal rats developed cancer after 4-nitroquinoline-N-oxide treatment, while six diabetic and six normal animals were used as controls. Oral sections were studied using monoclonal antibodies against IRS-1 and FAK proteins. Expression of IRS-1 was significantly higher in diabetic than normal rats, but it decreased in diabetic animals with tumor, especially in more advanced stages. FAK expression was significantly higher in rats with cancer in comparison to the ones without it, regardless the diabetes status. These data suggest that the IRS-1/FAK pathway is altered by diabetes resulting in reduced cell adhesion and possibly increasing risk for oral cancer.

Retrospective study of survival and treatment pattern in a cohort of patients with oral and oropharyngeal tongue cancers from 1987 to 2004

This is a retrospective study of patients with oral and oropharyngeal tongue cancers who presented to the Royal Adelaide Hospital (RAH) from 1987 to 2004. The aims of this study were to determine sociodemographic and tumour characteristics, treatment patterns and five-year disease-specific survival of the disease. All cases of tongue cancers, including untreated and palliative cases, were identified through the Royal Adelaide Hospital Cancer Registry and were included in statistical analysis. A total of 212 cases of tongue cancer were identified. Patients less than 45 years of age accounted for 15% of cases and had a tendency to present with advanced stage disease. Squamous cell carcinoma was the most common histological type. Almost 30% of recorded cases were oropharyngeal or base of tongue cancers. Nearly half of the patients had advanced stage (III and IV) disease at presentation, which was significantly associated with rural area of residence, base of tongue sub-site and early diagnostic period. Treatment involved a multidisciplinary approach and majority of patients were treated with a curative intent. Palliative treatment was more likely to be given to patient with oropharyngeal tongue cancers or advance stage disease. There was no significant improvement of five-year disease-specific survival over the 18-year period. Poorer survival was significantly associated with age 45 years or older, oropharyngeal tongue cancers and advanced stage disease. Tongue cancer is an important health issue associated with poor survival. Early detection and diagnosis is important in order to improve survival rate for this malignancy.

Efficacy of conventional and implant-supported mandibular resection prostheses: study overview and treatment outcomes

STATEMENT OF PROBLEM

While surgical restoration of mandibular resections has advanced dramatically with free-flap techniques, oral function and patient perceptions of function, as well as treatment outcomes, often indicate significant impairment.

PURPOSE

This longitudinal prospective study was designed to determine whether conventional prostheses (CP) or implant-supported prostheses (IP) and current surgical reconstructive procedures restore patients' oral functions and quality of life to their status prior to segmental mandibulectomy with immediate fibula free-flap reconstruction. Study design and implementation, characteristics of the study sample, treatment completion rates, and selected presurgical and postsurgical functional and perceptual outcomes are presented.

MATERIAL AND METHODS

Forty-six subjects were enrolled. Longitudinal evaluations of medical and dental histories, oromaxillofacial examinations, questionnaires, and sensory and functional tests were planned before and after surgery and after CP and IP treatment. Sample characteristics are described with descriptive statistics and comparisons of subject responses to questionnaire items at entry and postsurgical intervals were made with Fisher exact tests (alpha=.05).

RESULTS

Conventional prostheses were completed in 33 of 46 subjects, and 16 of 33 CP subjects were treated with IP. Reasons for noncompletion of IP were recurrent/metastatic disease (16), refusal of implant therapy (7), lost to follow-up (4), treatment with a reconstruction plate (1), excessive radiation at implant sites (1), and death (1). All 16 recurrences/metastases occurred within 13 months of surgery. Only 3 of the 58 implants placed in 17 participants were considered failures. One failed due to lack of integration 31 weeks following placement, and 2 were buried due to unacceptable positioning for prosthetic restoration during denture fabrication. The remaining 55 implants were successful at final evaluation, ranging from 58 to 123 weeks following implant placement (mean duration=78.9 +/- 16.0 weeks).

CONCLUSIONS

While 72% (33/46) of the subjects enrolled were able and willing to complete treatment with CP, only 35% (16/46) completed IP treatment. Careful consideration must be given to selection of the type of prosthetic rehabilitation and the timing of implant placement if an IP is planned.

The efficacy of oral lumenoscopy (ViziLite) in visualizing oral mucosal lesions

Early diagnosis of oral mucosal lesions has been advocated as a means of improving outcomes of cancer therapy. Improved visualization of mucosal lesions may aid in diagnosis by guiding tissue sampling or referral. This multicenter study reports the effect of chemiluminescent light (ViziLite) upon visualization of mucosal lesions. The chemiluminescent light did not appear to improve visualization of red lesions, but white lesions and lesions that were both red and white showed enhanced brightness and sharpness.

Disparities in oral and pharyngeal cancer incidence, mortality and survival among black and white Americans

BACKGROUND

The authors present statistics and long-term trends in oral and pharyngeal cancer (OPC) incidence, mortality and survival among U.S. blacks and whites.

METHODS

The authors obtained incidence, mortality and five-year relative survival rates via the Surveillance, Epidemiology and End Results (SEER) Program Web site. Current rates and time trends for 1975 through 2002 are presented.

RESULTS

From 1975 through 2002, age-adjusted incidence rates (AAIRs) and mortality rates (AAMRs) were higher among males than among females and highest for black males. By the mid-1980s, incidence and mortality rates were declining for black and white males and females; however, disparities persisted. During the period 1998-2002, AAIRs were more than 20 percent higher for black males compared with white males, while the difference in rates for black and white females was small. AAMRs were 82 percent higher for black males compared with white males, but rates were similar for black and white females. Five-year relative survival rates for patients diagnosed during the period 1995-2001 were higher for whites than for blacks and lowest for black males.

CONCLUSIONS

Despite recent declines in OPC incidence and mortality rates, disparities persist. Disparities in survival also exist. Black males bear the brunt of these disparities.

PRACTICE IMPLICATIONS

Dentists can aid in reducing OPC incidence and mortality by assisting patients in the prevention and cessation of tobacco use and alcohol abuse. Five-year relative survival may be improved through early detection.

An Overview of Epidemiology and Common Risk Factors for Oral Squamous Cell Carcinoma

Understanding the epidemiologic picture and the risk factors for oral cancer can help identify and treat patients at risk for oral cancers. Early diagnosis of an oral cancer continues to be important to achieving a favorable prognosis. Absent a diagnosis of oral/pharyngeal cancer, there clearly can-lot be an effective treatment plan. Discovering a potentially malignant or malignant lesion and through biopsy reaching a diagnosis for the lesion begins by performing an examination with the purpose of detecting oral/pharyngeal lesions. An oral cancer screening can be performed in less than five minutes without any expensive diagnostic aids. Despite the ease with which this exam can be performed and the noninvasive nature of the examination,most patients report that they have never had an oral cancer examination. Late stage diagnosis continues to be a common situation resulting in high rates of morbidity and mortality. Without early recognition it seems that the trend of late stage diagnosis will continue. Physicians, dentists, and other health care providers should be performing the oral cancer screening examination on a routine basis for all of their patients.Note: For the interested clinician, the author highly recommends an excellent comprehensive text on the subject of oral cancer. Sol Silverman's(with multiple contributors) The American Cancer Society's Atlas of Clinical Oncology Oral Cancer: Fifth Edition by BC Decker Publishers is an excellent overview of oral cancer covering in greater detail many of the subjects that could not be covered in this brief article. Additionally, there are excellent color photographs of the common presentations of oral malignancies that can be helpful in assessing oral/pharyngeal lesions.

Oral cancer: the association between nation-based alcohol-drinking profiles and oral cancer mortality

The unclear association between different nation-based alcohol-drinking profiles and oral cancer mortality was investigated using, as observational units, 20 countries from Europe, Northern America, Far Eastern Asia, with cross-nationally comparable data. Stepwise multiple regression analyses were run with male age-standardised, mortality rate (ASMR) as explanatory variable and annual adult alcohol consumption, adult smoking prevalence, life expectancy, as explanatory. Large between-country differences in ASMR (range, 0.88-6.87 per 100,000) were found, but the mean value was similar to the global estimate (3.31 vs. 3.09 per 100,000). Differences in alcohol consumption (2.06-21.03 annual litres per capita) and in distribution between beverages were reported. Wine was the most prevalent alcoholic beverage in 45% of cases. Significant increases in ASMR for every litre of pure ethanol (0.15 per 100,000; 95 CI, 0.01-0.29) and spirits (0.26 per 100,000; 95 CI, 0.03-0.49), non-significant effects for beer and wine were estimated. The impact of alcohol on oral cancer deaths would be higher than expected and the drinking profile could affect cancer mortality, probably because of the different drinking pattern of spirit drinkers, usually consuming huge alcohol quantities on single occasions, and the different concentrations of ethanol and cancer-preventing compounds such as polyphenols, in the various beverages.