Monthly Archives: November 2009

The oral cancer epidemic in central and eastern Europe

Source: Int J Cancer, October 30, 2009
Author: Werner Garavello et al.

To monitor recent trends in oral and pharyngeal cancer mortality in 38 European countries, we analyzed data provided by the World Health Organization over the period 1975-2004. Joinpoint analysis was used to identify significant changes in trends.

In the European Union (EU), male mortality rates rose by 2.1% per year between 1975 and 1984, by 1.0% between 1984 and 1993, and declined by 1.3% between 1993 and 2004, to reach an overall age-standardized rate of 6.1/100,000 in 2000-2004. Mortality rates were much lower in women, and the rate in the EU rose by 0.9% per year up to 2000, and levelled off to 1.1/100,000 in 2000-2004.

In France and Italy – which had the highest rates in the past – male rates have steadily declined during the last two decades (annual percent change, APC=-4.8% in 1998-2004 in France, and -2.6% in 1986-2003 in Italy). Persisting rises were, however, observed in several central and eastern European countries, with exceedingly high rates in Hungary (21.1/100,000; APC=6.9% in 1975-1993 and 1.4% in 1993-2004) and Slovakia (16.9/100,000; APC=0.14% in 1992-2004). In middle aged (35 to 64) men, oral and pharyngeal cancer mortality rates in Hungary (55.2/100,000) and Slovakia (40.8/100,000) were comparable to lung cancer rates in several major European countries. The highest rates for women were in Hungary (3.3/100,000; APC=4.7% in 1975-2004) and Denmark (1.6/100,000; APC=1.3% in 1975-2001).

Oral and pharyngeal cancer mortality essentially reflects the different patterns in tobacco smoking and alcohol drinking, including drinking patterns and type of alcohol in central Europe.

Authors:
Werner Garavello, Paola Bertuccio, Fabio Levi, Franca Lucchini, Cristina Bosetti, Matteo Malvezzi, Eva Negri, and Carlo La Vecchia

Authors’ affiliation:
Istituto di Ricerche Farmacologiche “Mario Negri”, Milan, Italy

November, 2009|Oral Cancer News|

Does green tea prevent cancer?

Source: www.ivanhoe.com
Author: staff

Evidence continues to brew about the protective effects of green tea against cancer, but scientists are still not sure the tea leaves reveal the answer.

Vassiliki Papadimitrakopoulo, M.D., professor of medicine in the Department of Thoracic/Head and Neck Medical Oncology at the University of Texas M. D. Anderson Cancer Center, and colleagues tested 41 patients who took green tea extract orally for three months at three dose levels.

Nearly 60 percent of patients with oral pre-malignant lesions, who were at the highest dose levels, displayed clinical response, compared with less than 20 percent among those taking placebo. Researchers also observed a trend toward improved histology, and a trend toward improvement in a handful of biomarkers that may be important in predicting cancer development.

Patients were followed for 27.5 months, and at the end of the study period, 15 developed oral cancer. Although there was no difference in oral cancer development overall between those who took green tea extract and those who did not, patients who presented with mild to moderate dysplasia had a longer time to develop oral cancer if they took green tea extract.

Although encouraged by the results, Dr. Papadimitrakopoulo cautioned against any recommendations that green tea could definitely prevent cancer.

“This is a phase II study with a very limited number of patients who took what would be the equivalent of drinking eight to 10 cups of green tea every single day,” Dr. Papadimitrakopoulo was quoted as saying. “We cannot with certainty claim prevention benefits from a trial this size.”

Dong Shin, M.D., professor of hematology and medical oncology and Blomeyer Endowed Chair in Cancer Research at Emory School of Medicine, agreed, but indicated he thought this trial was certainly a step in the right direction.

“A clinical trial with a natural compound is no easy task, and these researchers have accomplished that,” Dr. Shin was quoted as saying. “The lack of toxicity is also important because often when you give supplements at higher doses than what would occur naturally, you induce nausea and vomiting. That did not happen in this trial.”

“The goal of this kind of research is to determine whether or not these supplements have long-term prevention effects,” Dr. Papadimitrakopoulou said. “More research including studies in which individuals at high risk are exposed to these supplements for longer time period is still needed to answer that sort of question.”

Source: Cancer Prevention Research, November, 2009

November, 2009|Oral Cancer News|

Hookah myths go up in smoke

Source:
Author: Kate Dopazo

Students, university health officials discuss misconceptions about smoking hookah

When Rajiv Ulpe, a public and community health master’s student, asked students to compare hookah to cigarettes Friday afternoon at a lecture on the campus, most attendees agreed hookah was a much healthier alternative to smoking cigarettes.

“I don’t think you can get addicted to hookah,” Nick Patcella, a junior civil engineering major, said. “I think you can get addicted to the social aspect because it’s a fun activity, but not the hookah itself.”

“People think it’s a lot less lethal than cigarettes,” senior cell biology major Ray Gonzalez, added. “The water takes out more of the impurities.”

But Ulpe said these are all common myths associated with hookah — a water pipe used to smoke tobacco through cooled water — adding that according to the Centers for Disease Control and Prevention, a typical hour-long hookah smoking session involves inhaling 100 to 200 times the volume of smoke inhaled in a single cigarette.

During the discussion, nine undergraduate students between the ages of 18 and 22 were asked to discuss their attitudes toward hookah and what exactly they know about its effects.

“Hookah is more natural than cigarettes and you smoke hookah less than cigarettes,” Patcella said.

Ulpe and Public and Community Health professor Nancy Atkinson held the event to learn about students’ knowledge, attitudes and myths surrounding hookah use. The consensus of the group was that most students do not know the consequences of smoking hookah because it is not a prevalent discussion.

Throughout the event, Ulpe targeted the common myths surrounding the practice, asking students if they thought they were true. Many students said they thought because hookah smoke is filtered through water, it filters out harmful ingredients. They also said they thought smoking hookah is less addictive than smoking cigarettes.

According to a University Health Center fact sheet, however, these beliefs aren’t true: The water does not filter out cancer-causing chemicals, and hookah smoke can damage the lungs and heart just as much as cigarette smoke. Shisha, the moist and sticky tobacco smoked in hookah, contains nicotine and is just as addicting as cigarettes.

According to the U.S. Centers for Disease Control and Prevention, hookah smokers are at risk for the same kinds of diseases caused by cigarette smoking, such as lung cancer, stomach cancer and oral cancer.

Ulpe said students need to be informed to stay safe. He will be interviewing three experts in the field of cessation, policy and communication to obtain recommendations for reducing hookah use on the campus.

November, 2009|Oral Cancer News|

Dentists your first defence in fight against oral cancer

Source: Timescolonist

Author: Johnathan Skuba

In 2003, an estimated 3,100 Canadians were newly diagnosed with oral cancer. That same year, 1,090 people died of the disease. In the U.S., oral cancer kills roughly one person per hour, 24 hours a day. Of those newly diagnosed, only half will survive five years later, and this terrifying death rate has not declined for decades.

Those statistics are frightening, but the good news is that early detection plays a major role in preventing or curing oral cancers. The first line of defence is the dentist. They are specifically trained to recognize even subtle changes in the mouth and take action.

Pre-malignant lesions usually manifest as white patches (leukoplakias) that can look like small calluses. They could be benign and nothing but skin thickened by trauma or normal wear and tear of oral tissues. Of greater concern are spots that become ulcers, bleed, rapidly change appearance or that are obviously getting larger. Red patches (erythroplakia) should also be examined as they too could represent cancerous tissue. If any such spots are present and either enlarge or don’t improve within 10-14 days, or if they disappear and then recur, patients are advised to see their dentists as soon as possible.

Once in the chair, patients will find that dentists do not take chances, especially when the spots appear in areas where normal trauma is unlikely, such as the soft palate of the mouth or under the tongue. When such spots are seen, and particularly when there is no known cause, the dentist will strongly recommend followup and refer the patient to an oral pathologist or an oral and maxillofacial surgeon for consultation and possible removal and biopsy. If the dentist believes that the lesion is likely not cancerous but still a possible concern, they may choose to closely monitor the area over a short time and make a referral if it remains suspicious upon followup.

“The best thing is to remove all suspicious lesions,” says Dr. Seema Ganatra, an oral pathologist who teaches at the University of Alberta. “Oral cancer has a similar progression to many other cancers such as cervical cancer. When dysplasia (abnormal cells) is seen, these cells may evolve into cancer cells if they are not removed. It is impossible to predict which lesions will go on to become cancer. Followup screening and patient education complete the cycle.”

Regular dental checkups are essential to protect one’s health, since early detection can save lives. Reducing risk factors is another way to promote good health, Ganatra says.

“Not surprisingly, people who smoke are at high risk for oral cancer, but so are those who consume large amounts of alcohol. People who are both heavy smokers and drinkers have 18 times the risk of developing oral cancer.”

Smokeless tobacco, cigars and pipe smoking are every bit as dangerous as cigarettes, she adds. And those with these increased risk factors who don’t regularly see a dentist face even greater peril.

“By the time their symptoms worsen enough for them to seek medical help, they are usually in the advanced stages of the disease.”

At present, 95 per cent of oral cancers are found in people over 45, but an alarming trend points to younger people getting the disease from another source. In people who don’t smoke or drink, there is a rise in oral cancer (and certain other cancers) due to specific strains of the human papilloma virus (HPV), a sexually transmitted infection most commonly associated with genital warts. According to the Oral Cancer Foundation, HPV-linked oral cancer is the fastest-growing segment of the oral cancer population.

Dentists have a number of screening tools such as rinses and fluorescent lights to help them spot signs of oral cancer, but visual diagnosis and biopsy remain the best detection methods, Ganatra says. “It is in the pathology lab that we have a better chance of making the diagnosis.”

Public awareness is key to lowering the incidence of oral cancer. Reduce or remove risk factors like tobacco, alcohol and unprotected sexual activity. Have regular dental checkups and schedule another appointment if you see unusual spots in your mouth or experience symptoms like fatigue or a hoarse throat in the absence of a cold or flu. Follow your dentist’s advice on prevention and treatment.

“Screening is vital,” says Ganatra. “Two-thirds of oral cancers are found in the late stages; if we had caught them early, those people might still be alive.”

Dr. Jonathan Skuba is a past president of the Alberta Dental Association and College. He has been in general practice in Edmonton since 2001.

“French” kissing ups risk of oral HPV infection

Source: The Journal of Infectious Diseases
Author: Staff

NEW YORK (Reuters Health) – Oral sex and open-mouthed “French” kissing increase the risk of acquiring oral infections of human papillomavirus, or HPV, a study shows.

“Performing oral sex is not without risks,” Dr. Maura L. Gillison told Reuters Health.

It is associated with gonorrheal pharyngitis – a sexually transmitted infection of the tonsils and back of the throat that immediately causes symptoms, she noted, and now is associated with mouth HPV infections that are silent “yet may lead to oral cancer 10 to 20 years later.”

Gillison from The Ohio State University, Columbus, and colleagues explored whether sexual behaviors were associated with the odds of oral HPV infection in 332 adults and in 210 college-aged men. They found that 4.8 percent of the adults and 2.9 percent of college-aged men had oral HPV infection.

Among adults, the odds of oral HPV infection were significantly elevated among current tobacco smokers and among individuals who reported having either more than 10 oral or more than 25 vaginal sex partners during their lifetime.

Similar risk factors applied to the college-aged men. For them, having at least six recent oral sex or open-mouthed kissing partners were independently associated with increased odds of developing oral HPV infection.

For the 28 percent of college-aged men who reported never having performed oral sex, having at least 10 lifetime or at least five recent open-mouthed kissing partners was associated with a significantly higher risk of developing oral HPV infection.

“Our data suggest that oral HPV infections that could predispose to cancer may be transmitted by very common behaviors such as open-mouth or ‘French’ kissing,” Gillison concluded.

Given that the HPV vaccine does not have any therapeutic value against pre-existing HPV infections, “this may be relevant to the timing of administration of vaccination,” Gillison said.

Although the CDC recommends that the vaccine be administered between the ages of 9 and 12 ideally, in practice, she noted, it is often administered to girls between the age of 14 and 16. Oral exposure to HPV may have occurred prior to that age.

SOURCE: The Journal of Infectious Diseases, November 9, 2009.

November, 2009|Oral Cancer News|

Incidence of carcinoma of the major salivary glands according to the WHO classification, 1992 to 2006: a population-based study in the United States

Source: CEBP.com
Author: Staff

Requests for reprints:
Graça M. Dores, Medical Service (111), Department of Veterans Affairs Medical Center, 921 North East 13th Street, Oklahoma City, OK 73104. Phone: 405-456-3325. E-mail: doresg@mail.nih.gov
Abstract

Background: Carcinomas of the major salivary glands (M-SGC) comprise a morphologically diverse group of rare tumors of largely unknown cause. To gain insight into etiology, we evaluated incidence of M-SGC using the WHO classification schema (WHO-2005).

Methods: We calculated age-adjusted incidence rates (IR) and IR ratios (IRR) for M-SGC diagnosed between 1992 and 2006 in the Surveillance, Epidemiology and End Results Program.

Results: Overall, 6,391 M-SGC (IR, 11.95/1,000,000 person-years) were diagnosed during 1992 to 2006. Nearly 85% of cases (n = 5,370; IR, 10.00) were encompassed within WHO-2005, and among these, males had higher IRs than females [IRR, 1.51; 95% confidence interval (95% CI), 1.43-1.60]. Squamous cell (IR, 3.44) and mucoepidermoid (IR, 3.23) carcinomas occurred most frequently among males, whereas mucoepidermoid (IR, 2.67), acinic cell (IR, 1.57), and adenoid cystic (IR, 1.40) carcinomas were most common among females. Mucoepidermoid, acinic cell, and adenoid cystic carcinomas predominated in females through age ∼50 years; thereafter, IRs of acinic cell and adenoid cystic carcinomas were nearly equal among females and males, whereas IRs of mucoepidermoid carcinoma among males exceeded IRs among females (IRR, 1.57; 95% CI, 1.38-1.78). Except for mucoepidermoid and adenoid cystic carcinomas, which occurred equally among all races, other subtypes had significantly lower incidence among Blacks and Asians/Pacific Islanders than among Whites. Adenoid cystic carcinoma occurred equally in the submandibular and parotid glands, and other M-SGC histologic subtypes evaluated had 77% to 98% lower IRs in the submandibular gland. Overall M-SGC IRs remained stable during 1992 to 2006.

Conclusion: Distinct incidence patterns according to histologic subtype suggest that M-SGC are a diverse group of neoplasms characterized by etiologic and/or biological heterogeneity with varying susceptibility by gender and race. (Cancer Epidemiol Biomarkers Prev 2009;18(11):2899–906)

November, 2009|Oral Cancer News|

GenVec receives orphan drug designation

Source: www.onemedplace.com
Author: staff

GenVec’s experimental drug to treat pancreatic cancer has been granted orphan drug status by the U.S. Food and Drug Administration (FDA). The drug candidate TNFerade stimulates the production of an immune system protein known for having anti-cancer effects. Shares in GenVec rose 25 percent following the announcement.

Last summer, Gaithersburg, Maryland-based GenVec announced positive data from a Phase II/III clinical trial of TNFerade. The drug provided a 42.5% reduction in the risk of death when combined with standard treatment, when compared to standard treatment alone. TNFerade is also being explored as a candidate to treat esophageal cancer, rectal cancer, and head and neck cancer.

Note:
The FDA grants orphan drug designation to drugs that may be significantly more effective than currently existing treatments, and target conditions that affect less than 200,000 U.S. patients per year. Upon approval, drugs granted orphan status enjoy seven years of marketing exclusivity in the United States.

November, 2009|Oral Cancer News|

Cetuximab continues to increase survival in patients with head and neck cancer for up to 5 years

Source: www.docguide.com
Author: staff

Adding cetuximab to radiation therapy prolongs survival in patients with locally advanced head and neck cancer compared with radiotherapy alone, and this improvement persists for up to 5 years.

As such, this combined treatment should be considered as a standard option for patients with advanced head and neck cancer, according to a study published online first and appearing in an upcoming issue of The Lancet Oncology.

The use of chemoradiotherapy has been shown to improve survival and has become a popular treatment, but is not ideal because of its associated side-effects and increased toxicity.

In 1999, a trial commenced to examine the effect of adding cetuximab to radiotherapy in patients with locally advanced head and neck cancers of the oropharynx, hypopharynx, and larynx. In total, 424 patients were randomly assigned to 6 to 7 weeks of radiotherapy alone (n = 213) or radiotherapy and cetuximab (n = 211).

The primary results of the trial showed that patients treated with cetuximab had a 13% improvement in absolute disease control and 10% improvement in absolute survival at 3 years without increased side-effects, compared with patients given radiotherapy alone.

In the current article, James Bonner, MD, University of Alabama, Birmingham, Alabama, and colleagues reported the long-term 5-year outcomes of patients involved in the original trial.

Overall, findings showed an improvement in absolute survival of about 9% in patients given cetuximab compared with those given radiotherapy alone (36.4% vs 45.6%) at 5 years.

Interestingly, patients treated with cetuximab who developed a prominent cetuximab-induced acne-like rash showed significantly improved overall survival compared with patients given cetuximab who developed a mild or no rash (> 68.8 months vs 25.6 months). They suggest that the rash could be a biomarker for an immunological response that is associated with a favourable outcome.

Further analyses also showed that various patient and tumour factors (such as having an oropharynx tumour, being male, and aged < 65 years) were associated with an improved benefit from combined treatment with cetuximab and radiotherapy compared with radiotherapy alone. "Future studies will be designed to help provide a pathway to individualised patient treatments," the authors wrote. "The analysis of molecular markers…will help refine our ability to select the patients who will benefit from the various systemic treatments to radiotherapy." Source: The Lancet Oncology

November, 2009|Oral Cancer News|

Patterns of alcohol and tobacco use affect head and neck cancer risk

Source: www.rtmagazine.com
Author: staff

Assuming that total exposure is the same, it is worse to smoke lightly for many years than to smoke heavily for a few years when it comes to the risk of head and neck cancer, new research shows. With alcohol use, however, the opposite is true.

The results, which were published in the October 15th issue of the American Journal of Epidemiology, also confirmed previous research showing that smoking was more strongly associated with laryngeal cancer and that alcohol consumption was more strongly associated with pharyngeal and oral cavity cancers.

“Cigarette smoking and alcohol consumption are known risk factors for head and neck cancers, including cancers of the larynx, oral cavity, and pharynx,” co-researcher Dr. Jay H. Lubin, of the National Cancer Institute, Rockville, Maryland, told Reuters Health. “This paper presented a detailed quantitative evaluation of their effects, using data which were pooled from 15 case-control studies.”

The researchers modeled the excess odds ratio (EOR) to assess risk by total exposure (pack-years and drink-years), as well as the modification of risk by exposure rate (cigarettes/day and drinks/day).

The smoking analysis included 1761 laryngeal, 2453 pharyngeal, and 1990 oral cavity cancer cases. For controls, 7963 were included for laryngeal and 10,114 for pharyngeal and for oral cavity cancer cases. The alcohol analysis included 2551 laryngeal, 3693 pharyngeal, and 3116 oral cavity cancer cases. For controls, 12,179 were included for laryngeal cancer and 15,589 for pharyngeal and oral cavity cancer cases.

While smoking increased the risk of all head and neck cancers, the association was markedly greater for larynx cancer than for pharyngeal and oral cavity cancers. The risk of cancers of the oral cavity and pharynx were similar.

In addition, the amount of additional smoking-related risk was influenced by the manner of cigarette consumption. “For example, suppose two individuals had the same total cigarette exposure (total pack-years of smoking),” Dr. Lubin explained. “Then, while both individuals will have substantially increased risk of head and neck cancer compared to someone who never smoked, the individual who smoked fewer cigarettes per day for longer duration had an even greater risk of disease than the individual who smoked more cigarettes per day for shorter duration.”

Alcohol consumption increased the odds ratios for all head and neck cancer sites relative to someone who never consumed alcohol. The risk patterns for oral cavity and pharynx cancers were again similar, with odds ratios greater for oral cavity/pharynx cancer than for larynx cancer.

“We again found that consumption patterns influenced disease risks,” Dr. Lubin said. “For two individuals with the same total alcohol consumption (drink-years), both will have an increased odds ratio for head and neck cancer, but the individual who consumed a greater number of drinks per day for a shorter duration would have an even greater risk of disease compared to the individual who consumed a smaller number of alcoholic drinks per day for a longer duration.”

Dr. Lubin noted that the patterns of odds ratios with smoking and drinking “may reflect underlying biological mechanisms. The patterns of odds ratios with smoking are consistent with several plausible biological mechanisms for the induction of cancer by various carcinogens in tobacco smoke, including increased DNA repair, saturation of activation pathways and increased induction of detoxification enzymes.”

Source:
Am J Epidemiol 2009;170:937-947.

November, 2009|Oral Cancer News|

Microarray technologies in the diagnosis and treatment of head and neck cancer

Source: emedicine.medscape.com
Authors: Perminder S Parmar, MD et al.

Introduction
Since the draft sequence of the human genome was published in 2001 (Lander, 2001), the Cancer Genome Anatomy Project index of tumor genes has classified more than 40,000 genes directly or indirectly involved in one or more cancers (Strausberg, 2001; Strausberg, 2000). Conventional techniques of gene investigation in cancer rely on the identification of single genetic alterations associated with disease. This has proven to be both time consuming and cost ineffective. The introduction of complementary DNA (cDNA) microarray technology in 1995 (Schena, 1995) has helped to facilitate the identification and classification of DNA sequence information and the assignment of functions to these new genes by allowing investigators to analyze expression of thousands of genes simultaneously in a single experiment.

Microarrays are a significant advance because they contain a very large number of genes and because of their small size. Therefore, microarrays are useful when one wants to survey a large number of genes quickly or when the study sample is small. Microarrays may be used to assay gene expression within a single sample or to compare gene expression in 2 different cell types or tissue samples, such as in healthy and diseased tissue. Because a microarray can be used to examine the expression of hundreds or thousands of genes at once, it promises to revolutionize the way gene expression is examined.

Methods
DNA microarrays are small solid supports onto which the sequences from thousands of different genes are attached at fixed locations. The supports themselves are usually glass microscope slides but can also be silicon chips or nylon membranes. The DNA is printed, spotted, or actually synthesized directly onto the support.

Messenger RNA (mRNA) from the sample of interest can serve as a template for producing complementary DNA (cDNA) in the presence of a reverse transcriptase enzyme. This cDNA can then be fluorescently labeled and hybridized to the target gene sequences on the microarray. A confocal scanner then reads the fluorescent intensity of each hybridized sequence in the array. The scanner that records the intensity value is linked to digital image analysis software, which produces a color-coded image of the array, and a quantitative value is recorded for each target gene. The intensity of fluorescence is analyzed and correlates with expression of the gene.

The data produced from a microarray experiment typically constitute a long list of measurements of spot intensities and intensity ratios, generated either by a pair-wise comparison of 2 samples or by a comparison of several samples with a common control. The challenge is to sort through this data to find meaningful results. Because of the complexity of the data sets generated by microarray experiments, the use of data-analysis software is essential. Several commercial and public data-analysis tools have been developed for this purpose.

Current Applications In Head And Neck Oncology
In recent years, the use of microarray technology has been of great interest in head and neck squamous cell carcinoma (HNSCCa). Microarrays may eventually help in the understanding of the disease and ultimately lead to improvements in diagnosis, treatment, and outcome (Warner, 2004). Furthermore, the quantitative and qualitative aspect of microarrays may eventually be exploited to screen for molecular markers of head and neck cancer (Sok, 2003). Numerous expression studies of HNSCCa have been performed (Sok, 2003; Belbin, 2002; Villaret, 2000; Leethanakul, 2000; Squire, 2002).

Belbin et al used complementary DNA (cDNA) microarrays that contained 9216 clones to measure global patterns of gene expression in HNSCCa. Through the use of statistical analysis, they identified 375 differentially expressed genes, which divided 17 patients with head and neck tumors into 2 clinically distinct subgroups based on gene-expression patterns. The results of their analysis demonstrated that gene-expression profiling can be used as a predictor of outcome and highlighted pathways, meriting exploration for possible links to outcome in HNSCC.

Using cDNA subtractive methodology in conjunction with microarray technology to screen for HNSCCa-specific genes, Villaret et al were able to identify 9 known genes that were significantly overexpressed in HNSCCa compared with healthy tissue specimens. In addition, they found 4 previously unidentified genes that were overexpressed in a subset of tumors.

Using a cDNA array of 588 known human cancer-related genes and 9 housekeeping genes, Leethanakul et al demonstrated a consistent decrease in the expression of differentiation markers, such as cytokeratins, and an increase in the expression of numerous signal-transducing and cell cycle regulatory molecules, as well as growth and angiogenic factors and tissue-degrading proteases. The authors also found that most HNSCCas overexpress members of the Wnt and Notch growth and differentiation regulatory system, suggesting that the Wnt and Notch pathways may contribute to squamous cell carcinogenesis.

In their study, Squire et al, using spectral karyotyping (SKY), comparative genomic hybridization (CGH), and microarrays, identified consensus regions of chromosomal imbalance and structural rearrangement in HNSCCa. The authors were able to demonstrate recurrent chromosomal alterations using CGH and SKY and to correlate them to expression array analysis.

In their study, Sok et al, using hierarchical clustering analysis, revealed that the gene-expression profiles obtained from a panel of 12,000 genes could distinguish tumor from nonmalignant tissues. Gene expression changes were reproducibly observed in 227 genes, representing previously identified factors associated with neoplasia. Furthermore, significant expression of the collagen type XI alpha-1 gene and a novel gene were reproducibly observed in all 9 tumors, whereas these genes were virtually undetectable in their corresponding, adjacent nonmalignant tissues.

Future
Despite strides in prevention and advances in treatment, cancer of the head and neck remains a disease of considerable morbidity and mortality. The use of complementary DNA (cDNA) microarray technology to explore gene expression on a global level is rapidly evolving. Although still in its infancy, cDNA microarray technology may prove helpful in the diagnosis, prognosis, and management of head and neck cancer.

Authors and affiliations:
James M Pearson, MD, Staff Physician, Department of Otolaryngology – Head and Neck Surgery, New York Eye and Ear Infirmary; Stimson P Schantz, MD, Head, Department of Otolaryngology, Division of Head and Neck Surgery, New York Eye and Ear Infirmary

November, 2009|Oral Cancer News|