Distinct array comparative genomic hybridization profiles in oral squamous cell carcinoma occurring in young patients

Genetic characteristics of advanced oral tongue squamous cell carcinoma in young patients

OBJECTIVES

We aimed to investigate genetic alterations in oral tongue squamous cell carcinoma (OTSCC) based on age and the clinical significance of these alterations in young OTSCC patients.

MATERIALS AND METHODS

We detected genetic alterations in 44 cases of advanced OTSCC through next-generation sequencing and analyzed and compared patients either younger or older than 45 years. Further analysis was conducted on a validation group of 96 OTSCC patients aged ≤ 45 years to examine the clinical and prognostic associations of TERT promoter (TERTp) mutations.

RESULTS

TP53 mutation was the most common genetic alteration in advanced OTSCC (88.6%), followed by TERTp mutation (59.1%), CDKN2A mutation (31.8%), FAT1 mutation (9.1%), NOTCH1 mutation (9.1%), EGFR amplification (18.2%), and CDKN2A homozygous deletion (4.5%). TERTp mutation was the only genetic alteration significantly enriched in young patients (81.3% in young versus 46.4% in older; P < 0.024). Within the validation group of young patients, TERTp mutation was identified in 30 cases (30/96, 31.3%) and tended to be related to both smoking and alcohol consumption (P = 0.072), higher stage (P = 0.002), more frequent perineural invasion (P = 0.094), and worse overall survival (P = 0.012) than wild type.

CONCLUSION

Our findings suggest that TERTp mutation is more frequent in young patients with advanced OTSCC and is associated with worse clinical outcomes. Therefore, TERTp mutation may serve as a prognostic biomarker for OTSCC in young patients. The findings of this study may help in developing personalized treatment strategies for OTSCC based on age and genetic alterations.

Comparison of tobacco and alcohol consumption in young and older patients with oral squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVE

To compare the proportion of young (up to 45 years of age) and older (over 45 years of age) oral squamous cell carcinoma (OSCC) patients who report tobacco and alcohol consumption.

METHODS

Observational studies reporting tobacco and alcohol consumption among young and older OSCC patients were selected in a two-phase process. Search strategies were conducted on five main electronic databases and complemented by grey literature. The risk of bias was assessed using the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data. Synthesis of results was calculated with the software R Statistics version 4.0.2 (The R Foundation).

RESULTS

From 6675 records identified, 38 studies met the eligibility criteria and were selected for qualitative synthesis and meta-analysis, encompassing 2439 young and 13,393 older patients. Tobacco smoking was reported by 39.5% (confidence interval (CI) = 31.7% to 47.9%, I2 = 78%) of the young patients and 48.4% (CI = 37.8% to 59.2%, I2 = 94%) of the older patients. Alcohol consumption was reported by 30.9% (CI = 22.7% to 40.5%, I2 = 83%) of the young and 45.8% (CI = 35.6% to 56.5%, I2 = 95%) of the older patients (P < 0.05).

CONCLUSION

The comparison in the proportion of individuals reporting tobacco and alcohol consumption demonstrated that these habits were more prevalent in the older group (48.4% and 45.8% respectively) than in the young group (39.5% and 30.9%, respectively).

CLINICAL RELEVANCE

As a significant proportion of patients with OSCC reported no habits, novel risk factors for OSCC need to be investigated in further research.

Are Survival Outcomes Different for Young and Old Patients with Oral and Oropharyngeal Squamous Cell Carcinoma? A Systematic Review and Meta-Analysis

Simple Summary

Oral cancer was considered a disease of old age. However, there has been a recent surge in the incidence of oral cancer in young individuals. Age dependence on survival outcomes such as overall survival, disease-free survival, recurrence, distant metastasis and second primary in surgically treated oral cancer has been investigated several times and the results differ. This systematic review and meta-analysis has been conducted to address this concern. The results of the present research may facilitate age-dependent prognosis stratification, which would assist in treatment planning in oral cancer patients.

Abstract

This systematic review and meta-analysis aims to address whether age can be a determinant of overall survival (OS), disease-free survival (DFS), recurrence, distant metastasis (DM) and second primary (SP) in surgically treated oral and oropharyngeal squamous cell carcinoma (OOPSCC). A total of 4981 cases and 44254 controls from 25 comparative observational studies were included in the analysis. A significantly better OS (matched subgroup analysis: OR 1.64; 95% CI 1.31–2.04, overall analysis: OR 1.48; 95% CI 1.09–2.01) was observed in young patients compared to older adults, with heterogeneity ranging from moderate to severe. Worse DFS (unmatched subgroup analysis OR 0.43; 95% CI 0.27–0.68) was observed in young patients compared to older adults with minimal to moderate heterogeneity. The frequency of recurrence (OR 1.49; 95% CI 1.10–2.02) and DM (OR 1.83; 95% CI 1.10–3.03) was significantly higher in the young patients, as found in unmatched and matched subgroup analysis, with the least heterogeneities. Young age can be considered as an independent prognostic factor for recurrence and distant metastases in OOP-SCC. Larger and methodologically robust observational studies with longer follow-up are needed to establish the definitive role of age as an independent prognostic factor on OS and DFS in OOPSCC.

Age-specific oncogenic pathways in head and neck squamous cell carcinoma - are elderly a different subcategory?

BACKGROUND

In recent clinical practice, an increasing number of elderly patients suffering from head and neck squamous cell carcinoma (HNSCC) of unknown pathophysiology is observed. The majority of HNSCC patients can roughly be divided into three subcategories. First, a small group of young patients who present with variants of genomic aberrations and inheritable diseases like Fanconi anaemia. Second, an increasing population of HPV-related HNSCCs that are regarded as genomic stable tumours with a more favourable prognosis. Though HPV-related tumours used to be more common among younger males, a notable rise in the elderly population is observed. The third subcategory, that of HPV-negative tumours, has been shown to be more heterogeneous with involvement of a variety of oncogenic pathways related to lifestyle factors like smoking and alcohol consumption, often seen in middle-aged males. Some of these pathways could be related to age, such as TP53 alterations, EGFR activation, apoptotic pathway alterations and field cancerization.

CONCLUSIONS

In this narrative review, we provide an overview of established and newly discovered age-specific pathophysiological mechanisms underlying HNSCC. We propose a fourth subcategory of patients with a suspected different pathophysiology: elderly (HPV-negative) HNSCC patients without a history of tobacco and alcohol consumption. In this subcategory, carcinogenesis seems to be a multi-step process based on genomic instability, immunosenescence, cell cycle disruption and telomere shortening. To conclude, we discuss suggestions for future research to fill the knowledge gap about age-dependent HNSCC carcinogenesis.

Survival Outcomes in Oral Tongue Cancer: A Mono-Institutional Experience Focusing on Age

Objective

The prognostic role of age among patients affected by Oral Tongue Squamous Cell Carcinoma (OTSCC) is a topic of debate. Recent cohort studies have found that patients diagnosed at 40 years of age or younger have a better prognosis. The aim of this cohort study was to clarify whether age is an independent prognostic factor and discuss heterogeneity of outcomes by stage and treatments in different age groups.

Methods

We performed a study on 577 consecutive patients affected by primary tongue cancer and treated with surgery and adjuvant therapy according to stage, at European Institute of Oncology, IRCCS. Patients with age at diagnosis below 40 years totaled 109 (19%). Overall survival (OS), disease-free survival (DFS), tongue specific free survival (TSFS) and cause-specific survival (CSS) were compared by age groups. Multivariate Cox proportional hazards models were used to assess the independent role of age.

Results

The median follow-up time was 5.01 years (range 0–18.68) years with follow-up recorded up to February 2020. After adjustment for all the significant confounding and prognostic factors, age remained independently associated with OS and DSF (respectively, p = 0.002 and p = 0.02). In CSS and TSFS curves, the role of age seems less evident (respectively, p = 0.14 and p = 0.0.37). In the advanced stage sub-group (stages III–IV), age was significantly associated with OS and CSS with almost double increased risk of dying (OS) and dying from tongue cancer (CSS) in elderly compared to younger groups (OS: HR = 2.16 95%, CI: 1.33–3.51, p= 0.001; CSS: HR = 1.76 95%, CI: 1.03–3.01, p = 0.02, respectively). In our study, young patients were more likely to be treated with intensified therapies (glossectomies types III–V and adjuvant radio-chemotherapy). Age was found as a prognostic factor, independently of other significant factors and treatment. Also the T–N tract involved by disease and neutrophil-to-lymphocyte ratio ≥3 were independent prognostic factors.

Conclusions

Young age at diagnosis is associated with a better overall survival. Fewer younger people than older people died from tongue cancer in advanced stages.

A systematic review and meta-analysis of the prognostic role of age in oral tongue cancer

While evidence suggests an increasing incidence of tongue cancer in young adults, published findings regarding the prognostic role of age at diagnosis are inconsistent. We performed a meta-analysis of the literature to highlight key points that might help in understanding the association between age of oral tongue cancer patients at diagnosis and their prognosis. According to age at diagnosis, a systematic literature review of all published cohort studies assessing the recurrence risks and mortality associated with tongue cancer was conducted. We compared the risk estimates between patients aged >45 years and those aged <45 years at diagnosis. Random-effects models were used to calculate summary relative risk estimates (SRRs) according to different clinical outcomes and sources of between-study heterogeneity (I2 ) and bias. We included 31 independent cohort studies published between 1989 and 2019; these studies included a total of 28,288 patients. When risk estimations were not adjusted for confounders, no significant association was found between age at diagnosis and overall survival (OS). Conversely, after adjustment for confounders, older age at diagnosis was associated with a significantly increased risk of mortality. The difference between SRRs for adjusted and unadjusted estimates was significant (p < 0.01). Younger patients had a significantly higher risk of local recurrence. Younger patients with oral tongue cancer have better OS but a greater risk of recurrence than older patients. These findings should be validated in a large prospective cohort study which considers all confounders and prognostic factors.

Young head and neck cancer patients are at increased risk of developing oral mucositis and trismus

OBJECTIVES

To evaluate cancer treatment-related toxicities in young head and neck cancer (HNC) patients.

MATERIAL AND METHODS

A total of 44 patients were included in the present retrospective cohort study, which was designed to access oral toxicities of cancer treatment in young (< 45 years of age, Group I, n = 22) and old (> 58 years of age, Group II, n = 22) HNC patients with similar tumor stage and treatment protocols. Oral mucositis (OM), xerostomia, dysphagia, dysgeusia, trismus, and radiodermatitis were assessed during days 7th, 21st, and 35th of head and neck radiotherapy (HNRT) according to previously validated scales (World Health Organization criteria and the National Cancer Institute and Common Terminology Criteria for Adverse Events version 4.0).

RESULTS

Patients from both groups showed high incidence and severity of oral toxicities by the end of the HNRT with OM (81.9% (Group I); 63.6% (Group II)) and xerostomia (72.6% (Group I); 77.2% (Group II)) being the most prevalent toxicities. No differences regarding xerostomia, dysphagia, dysgeusia, and radiodermatitis incidences or severity could be observed between groups. However, higher incidences and severity of OM at 21st and 35th fractions (odds ratio = 2.22 and 5.71, respectively) and trismus at 21st and 35th fractions (odds ratio = 6.17 and 14.5, respectively) were observed throughout the treatment in young patients when compared to older patients (p < 0.01 and p < 0.05, respectively).

CONCLUSION

Young HNC patients are more affected by cancer treatment-related OM and trismus despite the similarities in clinical staging and treatment protocols with elderly patients.

Head and neck cancer during pregnancy

BACKGROUND

The incidence of cancer during pregnancy is low but is slightly increasing. Data on incidence and etiology of head and neck (HN) cancers in pregnant women are rare. We evaluated the frequency, tumor type, associated factors, and specific biomarkers in HN cancers occurring in pregnant (and peripartum) women.

METHODS

A systematic literature search was performed on PubMed, for any HN tumor site occurring in pregnant women.

RESULTS

Sixty cases of HN cancers occurring during pregnancy were identified. Most of them were oral cavity cancers. Relationships with oncogenic viruses, hormonal disturbance, and shift in maternal immunity profile were identified.

CONCLUSION

Carcinogenesis of HN cancers in pregnant women may be led by different cancer type-specific hallmarks. Relevance of these etiological factors with respect to treatments and birth control recommendations is being investigated by the REFCOR in an ambispective study.

The protective effect of p16(INK4a) in oral cavity carcinomas: p16(Ink4A) dampens tumor invasion-integrated analysis of expression and kinomics pathways

A large body of evidence shows that p16(INK4a) overexpression predicts improved survival and increased radiosensitivity in HPV-mediated oropharyngeal squamous cell carcinomas.(OPSCC). Here we demonstrate that the presence of transcriptionally active HPV16 in oral cavity squamous cell carcinomas does not correlate with p16(INK4a) overexpression, enhanced local tumor immunity, or improved outcome. It is interesting that HPV-mediated oropharyngeal squamous cell carcinomas can be categorized as having a 'nonaggressive' invasion phenotype, whereas aggressive invasion phenotypes are more common in HPV-negative squamous cell carcinomas. We have developed primary cancer cell lines from resections with known pattern of invasion as determined by our validated risk model. Given that cell lines derived from HPV-mediated oropharyngeal squamous cell carcinomas are less invasive than their HPV-negative counterparts, we tested the hypothesis that viral oncoproteins E6, E7, and p16(INK4a) can affect tumor invasion. Here we demonstrate that p16(INK4a) overexpression in two cancer cell lines (UAB-3 and UAB-4), derived from oral cavity squamous cell carcinomas with the most aggressive invasive phenotype (worst pattern of invasion type 5 (WPOI-5)), dramatically decreases tumor invasiveness by altering expression of extracellular matrix remodeling genes. Pathway analysis integrating changes in RNA expression and kinase activities reveals different potential p16(INK4a)-sensitive pathways. Overexpressing p16(INK4a) in UAB-3 increases EGFR activity and increases MMP1 and MMP3 expression, possibly through STAT3 activation. Overexpressing p16(INK4a) in UAB-4 decreases PDGFR gene expression and reduces MMP1 and MMP3, possibly through STAT3 inactivation. Alternatively, ZAP70/Syk might increase MUC1 phosphorylation, leading to the observed decreased MMP1 expression.

Role of human papillomavirus in oropharyngeal squamous cell carcinoma: A review

Human papillomavirus (HPV) has been implicated in the pathogenesis of a subset of oropharyngeal squamous cell carcinoma. As a result, traditional paradigms in relation to the management of head and neck squamous cell carcinoma have been changing. Research into HPV-related oropharyngeal squamous cell carcinoma is rapidly expanding, however many molecular pathological and clinical aspects of the role of HPV remain uncertain and are the subject of ongoing investigation. A detailed search of the literature pertaining to HPV-related oropharyngeal squamous cell carcinoma was performed and information on the topic was gathered. In this article, we present an extensive review of the current literature on the role of HPV in oropharyngeal squamous cell carcinoma, particularly in relation to epidemiology, risk factors, carcinogenesis, biomarkers and clinical implications. HPV has been established as a causative agent in oropharyngeal squamous cell carcinoma and biologically active HPV can act as a prognosticator with better overall survival than HPV-negative tumours. A distinct group of younger patients with limited tobacco and alcohol exposure have emerged as characteristic of this HPV-related subset of squamous cell carcinoma of the head and neck. However, the exact molecular mechanisms of carcinogenesis are not completely understood and further studies are needed to assist development of optimal prevention and treatment modalities.

Genomic DNA copy number alterations from precursor oral lesions to oral squamous cell carcinoma

Oral cancer is a multifactorial disease in which both environmental and genetic factors contribute to the aetiopathogenesis. Oral cancer is the sixth most common cancer worldwide with a higher incidence among Melanesian and South Asian countries. More than 90% of oral cancers are oral squamous cell carcinoma (OSCC). The present study aimed to determine common genomic copy number alterations (CNAs) and their frequency by including 12 studies that have been conducted on OSCCs using array comparative genomic hybridization (aCGH). In addition, we reviewed the literature dealing with CNAs that drive oral precursor lesions to the invasive tumors. Results showed a sequential accumulation of genetic changes from oral precursor lesions to invasive tumors. With the disease progression, accumulation of genetic changes increases in terms of frequency, type and size of the abnormalities, even on different regions of the same chromosome. Gains in 3q (36.5%), 5p (23%), 7p (21%), 8q (47%), 11q (45%), 20q (31%) and losses in 3p (37%), 8p (18%), 9p (10%) and 18q (11%) were the most common observations among those studies. However, losses are less frequent than gains but it appears that they might be the primary clonal events in causing oral cancer.

The transcriptional regulatory network of proneural glioma determines the genetic alterations selected during tumor progression

Proneural glioblastoma is defined by an expression pattern resembling that of oligodendrocyte progenitor cells and carries a distinctive set of genetic alterations. Whether there is a functional relationship between the proneural phenotype and the associated genetic alterations is unknown. To evaluate this possible relationship, we performed a longitudinal molecular characterization of tumor progression in a mouse model of proneural glioma. In this setting, the tumors acquired remarkably consistent genetic deletions at late stages of progression, similar to those deleted in human proneural glioblastoma. Further investigations revealed that p53 is a master regulator of the transcriptional network underlying the proneural phenotype. This p53-centric transcriptional network and its associated phenotype were observed at both the early and late stages of progression, and preceded the proneural-specific deletions. Remarkably, deletion of p53 at the time of tumor initiation obviated the acquisition of later deletions, establishing a link between the proneural transcriptional network and the subtype-specific deletions selected during glioma progression.

TP53 mutation and human papilloma virus status of oral squamous cell carcinomas in young adult patients

OBJECTIVE

Little is known about the molecular carcinogenesis of oral squamous cell carcinoma (OSCC) in young adult patients. The aim of this study was to investigate the detailed TP53 mutation and human papilloma virus (HPV) status of OSCC in patients, younger than 45 years.

METHODS

TP53 mutations were determined with direct sequencing on paraffin-embedded carcinoma tissue from 31 young patients and compared with two older age OSCC reference groups: one from the same institute (N = 87) and an independent one (N = 675). Biologically active tumour HPV was detected by p16-immunohistochemistry followed by a HPV-DNA GP5 + /6 + -PCR.

RESULTS

HPV16 was present in one OSCC (3%). TP53 mutations were found in 14 (45%) OSCC: five were missense and nine resulted in a truncated protein. Six of these latter were insertions or deletions of one or more nucleotides leading to frameshift, one was at a splice site and two resulted in a stop codon. The percentage of truncating mutations (64% of all mutations) was higher than that observed in the institute's reference group (44%, P = 0.23) and in the independent reference group (24%, P = 0.002).

CONCLUSIONS

This study shows that TP53 mutations are common in OSCC of young adult patients; infection with biologically active HPV is rare.

WWP1 gene is a potential molecular target of human oral cancer

OBJECTIVE

This study investigates the oncogenic role of WWP1, an ubiquitin ligase linked to tumor promotion, in oral cancer.

STUDY DESIGN

An array-based comparative genomic hybridization was used to detect chromosomal changes in 10 oral cancer specimens. An additional 59 specimens and 6 cultured oral cancer cells were further examined to evaluate changes in the DNA copy number and messenger RNA (mRNA) and protein expression of WWP1.

RESULTS

The copy number of the WWP1 gene and its mRNA levels were significantly increased in the oral cancer specimens. An elevated WWP1 gene expression was observed in 6 cultured oral cancer cell lines. Knockdown of the endogenous WWP1 using small hairpin RNA further showed that deficiency of WWP1 suppressed cell growth and caused apoptosis in oral cancer cells.

CONCLUSION

Our results reveal that WWP1 might play an oncogenic role in oral cancer cells.

Potential role of septins in oral carcinogenesis: An update and avenues for future research

Septins belong to the GTPase superclass of conserved proteins and have been identified to play a role in diverse aspects of cell biology, from cytokinesis to the maintenance of cellular morphology. At least 14 septins have been identified in humans. With their complex patterns in gene expressions and interaction, it has been reported that alterations in septin expression are observed in human diseases. Although much is not known about the role of human septins in oral carcinogenesis, circumstantial evidence does indicate that it may play a major role. This review intends to summarize the basis of septin biology, with the focus being on the evidence for septin involvement in human oral cancer.

Serum decoy receptor 3 level: a predictive marker for nodal metastasis and survival among oral cavity cancer patients

BACKGROUND

Validating markers for prediction of nodal metastasis could be beneficial in treatment of oral cavity cancer. Decoy receptor 3 (DcR3), locus on 20q13, functions as a death decoy inhibiting apoptosis mediated by the tumor necrosis factor receptor (TNFR) family.

METHODS

This study analyzed the serum level of DcR3 in relationship to the clinical parameters of oral cavity cancer patients together with detection of DcR3 genomic copy number in primary and recurrent tumors.

RESULTS

Elevated serum DcR3 was associated with nodal metastasis and worse prognosis. Gain of DcR3 copy number was detected in 17% of primary tumor tissue but not found in healthy areca chewers. Tissue from recurrent tumors showed more frequent DcR3 copy number alteration (48%) than the paired primary tumor tissue.

CONCLUSIONS

Serum DcR3 level is a predictor for the nodal metastasis and survival among oral cavity cancer patients and the DcR3 copy number alteration could underlie oral carcinogenesis progression.

Human Papillomavirus and Oropharyngeal Squamous Cell Carcinoma: A Case-Control Study regarding Tobacco and Alcohol Consumption

We aimed to determine the role of HPV in the pathogenesis and outcome of oropharyngeal squamous cell carcinoma (OSCC) in lifelong nonsmoking and nondrinking patients. A case-case analysis was performed to compare the presence of HPV-DNA in tumor cells of 16 nonsmoking and nondrinking with 16 matched smoking and drinking patients (matching criteria: age at incidence, gender, tumor sublocation, tumor stage). HPV was detected using 2 PCR tests, FISH analysis, and p16^INK4A immunostaining. Nonsmoking and nondrinking patients had more HPV-positive tumors than smoking and drinking patients (n = 12; 75% versus n = 2; 13%; P < 0.001). All HPV-positive tumors showed p16^INK4A overexpression, and 1 HPV-negative tumor had p16^INK4A overexpression, (P < 0.001). Overall survival and disease-specific survival were higher for HPV-positive compared to HPV-negative cases (P = 0.027, P = 0.039, resp.). In conclusion, HPV is strongly associated with OSCC of nonsmoking and nondrinking patients. Specific diagnostic and therapeutic actions should be considered for these patients to achieve a better prognosis.

Telomere dysfunction promotes metastasis in a TERC null mouse model of head and neck cancer

Squamous cell carcinoma arises from highly proliferative basal layer epithelial cells, which normally divide for a short time before detaching from the basement membrane and undergoing terminal differentiation. Basal layer cells in stratified epithelia express the reverse transcriptase known as telomerase. Most human cells do not express telomerase and therefore are subject to loss of telomeric DNA with age due to the inability of lagging strand synthesis to completely replicate chromosomal ends. Late generation telomerase deficient mice exhibit signs of premature aging including reduced function of proliferating cellular compartments. We examined development of squamous cell carcinoma in a telomerase deficient murine background with long and short telomeres. G1 Terc-/- mice (long telomeres) had fewer lymph node metastases, which correlated with increased numbers of apoptotic cells in these tumors compared with wild-type mice. However, G5 Terc-/- mice with short telomeres had increased metastatic tumor burden similar to wild type mice. This increased metastasis correlated with genomic instability and aneuploidy in tumor cells from G5 Terc-/- mice. A number of similarities with human SCC were noted in the mouse model, and dramatic differences in global gene expression profiles were shown between primary and metastatic tumors. We concluded that telomere shortening promotes metastatic tumor development in a Terc null mouse model of head and neck cancer.

Molecular diagnostics for head and neck pathology

Molecular diagnostic techniques are quickly finding a role in the detection and diagnosis of tumors, and in predicting their behavior. They may also prove useful in developing new therapeutic approaches to head and neck cancer. The surgeon working in the craniomaxillofacial region should have an understanding of these technologies, their availability in various settings, and how they affect various aspects of treatment, particularly in the detection and treatment of malignancies. This article offers an overview of recent advances in molecular diagnostic techniques, with their implications for diagnosis and management of head and neck tumors.

Head and neck cancer in young people: a series of 52 SCCs of the oral tongue in patients aged 35 years or less

CONCLUSION

Prognosis was very poor as soon as a local failure developed. Up-front treatment should be optimized to control this rare disease. We propose producing and reporting recommendations via a concerted oncologic physician referral network.

OBJECTIVES

Squamous cell carcinoma (SCC) in young people is rare and the literature is confusing. This study was carried out to assess the demographics, clinical features, and treatment outcome in a cohort of patients aged 35 years or less with SCC of the oral tongue (SCCOT).

PATIENTS AND METHODS

This was a multicenter retrospective study. Fifty-two patients treated between 1990 and 2000 were identified. Descriptive statistics were analyzed to assess demographic and tumor variables.

RESULTS

The WHO performance status was excellent for all patients. Thirty-seven were classified as T1-T2 and 38 were N0. All of them except one were treated with curative intent. Treatment failures were observed in 25 patients (48%). Four patients could be successfully salvaged after SCCOT recurrence or progression. The disease-free survival (DFS) was 52% at 5 years. The 5-year overall survival (OS) rate was 64%. Factors that affected the OS were invasion of the floor (p=0.009), cross over of the midline (p=0.02), positive lymph nodes (p=0.02), and the lack of disease control (p=0.0001).

Head and neck squamous cell carcinoma in the young: a spectrum or a distinct group? Part 2

A recent increase in the number of young patients (often nonsmokers) developing head and neck squamous cell carcinoma (HNSCC) has been documented, however, there remains no clear evidence to support the significance of any single determinant. The typical HNSCC arises as a result of a multistep process and the progression model involving multiple genetic and epigenetic events is thought to be relatively consistent. While the progression model itself may be consistent, detection methods used in genomic studies are variable and all have their limitations. This article reviews changes at a molecular level in the typical HNSCC patient (the over 40 year old male smoker) and compares the profile to that of the young adult with HNSCC. Human papillomavirus infection with high risk types 16 and 18 has widely been reported as one of the prominent mechanisms behind the development of oropharyngeal cancer. A review of recent studies in relation to HPV and HNSCC is undertaken in this article, in an effort to examine the role that HPV plays in the development of HNSCC in young adults.

Evolving 'omics' technologies for diagnostics of head and neck cancer

Squamous cell carcinoma of head and neck (SCCHN) is the sixth most common malignancy and is a major cause of cancer morbidity and mortality worldwide. As with most solid cancers, the cure rate for SCCHN is excellent if tumors are diagnosed early in the course of the disease. Early diagnosis of cancer remains difficult because of the lack of specific symptoms in early disease as well as the limited understanding of etiology and oncogenesis. Advances in proteomics and genomics contribute to the understanding of the pathophysiology of neoplasia, cancer diagnosis and anticancer drug discovery. The powerful 'omics' technologies have opened new avenues towards biomarker discovery, identification of signaling molecules associated with cell growth, cell death, cellular metabolism and early detection of cancer. Analysis of tumor-specific omics profiles provided a unique opportunity to diagnose, classify, and detect malignant disease; to better understand and define the behavior of specific tumors; and to provide direct and targeted therapy. These technologies however still require integration and standardization of techniques and validation against accepted clinical and pathologic parameters. This article provides a summary of technologies, potential clinical applications, and challenges of omics in head and neck cancer.

Molecular pathogenesis of head and neck cancers

Head and neck cancers represent a progressive genetic malady, with genetic aberrations accumulating in response to carcinogen exposure. Although individual genomic aberrations develop at specific time points in the progression axis, the precise role of these abnormalities in tumor progression and cancer behavior remain to be elucidated. This article will give an overview of the current knowledge on the molecular basis for the development of head and neck cancers.

p16(INK4A) genetic and epigenetic profiles differ in relation to age and site in head and neck squamous cell carcinomas

Head and neck squamous cell carcinoma (HNSCC) typically affects male smokers older than 55 years. Recently, an increase in the incidence of HNSCC in young adults has been recognized, many of them nonsmokers and females. Functional inactivation of p16 is known to be a common event in HNSCC, mainly by either deletion or methylation. A previous study by this group has shown that p16 deletions in HNSCC are significantly associated with age. The primary objective of this study was to evaluate additional molecular alterations of p16 in HNSCC, specifically in relation to age, site, and human papillomavirus (HPV) status. Patients ranging in age from 22 to 76 years with HNSCC were prospectively identified (n = 24). Methylation-specific polymerase chain reaction and immunohistochemistry were used to evaluate p16 gene inactivation and p16 protein expression, respectively. HPV 16 status was determined for each case. Overall, p16 inactivation was a frequent event detected in 46% of cases. Methylation of p16 was more often detected in females than males (P = .05). All cases showing p16 methylation were from the anterior tongue, and 75% of them were young patients. The results indicate that p16 methylation is a more common event in those younger than 40 years in contrast to p16 deletions, which are more common in those older than 40 years. Consequently, it appears that specific modes of inactivation of p16 in HNSCC are related to specific patient risk profiles. Interestingly, HPV 16 messenger RNA was detected exclusively in HNSCC from the base of tongue lesions and was only found in males. This differs from the patient profile of HNSCC in the young, which affects the anterior tongue and commonly females, thus, making it highly unlikely that this virus is a primary causative agent of HNSCC in these young adults.

Low-level genomic instability is a feature of papillary thyroid carcinoma: an array comparative genomic hybridization study of laser capture microdissected papillary thyroid carcinoma tumors and clonal cell lines

CONTEXT

Previous chromosomal comparative genomic hybridization (CGH) studies of papillary thyroid carcinoma (PTC) have demonstrated a low prevalence of aberrations, with the majority of tumors showing no evidence of chromosomal instability. The technique of CGH can be optimized, however, using array CGH and laser capture microdissection to ensure pure cell populations for analysis.

OBJECTIVE

To assess PTC using array CGH applied to laser capture microdissected tumor cells and pure cell cultures.

DESIGN

Well-characterized PTC (known ret/PTC and BRAF mutation status), including samples from 5 tumors with classic morphology, 3 follicular variant tumors, and 3 clonal PTC cell lines, were analyzed.

RESULTS

Copy gain and loss occurred in all of the tumor cases and cell lines examined. The most common recurrent aberrations involved gains on chromosomes 1, 5, 7, 11, 15, 17, and 22, with recurrent deletions occurring on chromosomes 4, 18, and 19. Analysis of the data from the 8 tumor samples showed that amplifications of TP73 (1p36.33), SNRPN (15q12), and PDGFB (22q13.1) occurred exclusively in tumors with a wild type BRAF.

CONCLUSIONS

This study shows a higher prevalence of aberrations detected using array CGH allied to laser capture microdissection than previously described in the literature, and it appears that the combination of laser capture microdissection and arrayed clones optimizes studies utilizing CGH. Copy gain of PDGFB occurs in a subset of tumors showing no evidence of mutated BRAF or rearranged ret, suggesting that copy gain of PDGFB may underlie the increased expression of platelet-derived growth factor described recently in the literature.