Effective HPV Vaccine Needed for Both Men and Women

Effective HPV Vaccine Needed for Both Men and Women Monday, 03 November 2008 A call to explore a broader use of HPV (human papillomavirus) vaccines and the validation of a simple oral screening test for HPV-caused oral cancers are reported in two studies by a Johns Hopkins Kimmel Cancer Center investigator. Leading HPV expert Maura Gillison, M.D., Ph.D., reports her latest work in the November 3, 2008, journal Clinical Cancer Research and in a Centers for Disease Control and Prevention (CDC) monograph. The CDC report on HPV-associated cancers appears on line November 3 and in the November 15, 2008, supplement edition of Cancer. She was the first to identify HPV infection as the cause of certain oral cancers and who identified multiple sex partners as the most important risk factor for these cancers. In the CDC report, believed to be the first and most comprehensive assessment of HPV-associated cancer data in the United States, investigators analyzed cancer registry data from 1998-2003 and found 25,000 cancer cases each year occurred at cancer sites associated with HPV infection. In additional analysis, Gillison and colleagues at the National Cancer Institute identified HPV infection as the underlying cause of approximately 20,000 of these cancers. Gillison and team found approximately 20,000 cases of cancer in the United States each year are caused by HPV infection. Oral cancers are the second most common type of HPV-associated cancers and are increasing in incidence in the U.S., particularly among men. Add to that anal, penile, vaginal, and vulvar cancers that are also linked to HPV infection, and Gillison says these cancers, when combined, equal the number of cervical cancers, the most common and well known of the cancers caused by HPV. While about one-quarter of HPV-linked cancers occur in men, vaccines are currently approved only for use in girls and young women for cervical cancer prevention. "We need to have a more comprehensive discussion of the potential impact the HPV vaccine could have on cancer rates among men and women in this country," says Gillison, associate professor of oncology. "Currently available HPV vaccines have the potential to reduce the rates of HPV-associated cancers, like oral and anal cancers, that are currently on the rise and for which there no effective or widely-applied screening programs." Gillison notes, however, that studies are needed to confirm that the vaccine effectively prevents HPV infections that lead to oral and anal cancers. Gillison's findings were part of a project known as ABHACUS (Assessing the Burden of Human Papillomavirus-Associated Cancers). The data studied came from the CDC's National Program of Cancer Registries and the National Cancer Institute's Surveillance, Epidemiology, and End Results program. More than 80 investigators from across the country participated in the project, which addressed a variety of HPV-cancer associated issues, including racial disparity, economic impact, behavioural risk factors, and cancer mortality. Other than prevention, early detection is held by cancer experts as the best way to control cancer. In the Clinical Cancer Research study, the first to track the disease and related oral infections over an extended period, Gillison found that simple "swish and spit" oral rinses can successfully track oral HPV infection over time. These findings open the door to a potential, non-invasive screening test to detect the disease and monitor for tumour recurrence. Head and neck cancer is the broad term for a variety of cancers of the oral cavity, including the tonsils, base of the tongue, and the side and back wall of the throat. The study found that oral rinses successfully detected high-risk HPV infections in patients with HPV 16-positive head and neck cancers for up to five years after treatment for their cancer. Gillison says the findings indicate a high rate of persistent infection and reaffirms the connection between high-risk types of HPV and HPV-positive head and neck cancers. In the study, the researchers used oral rinses to collect cells shed from inside the mouths of 135 head and neck cancer patients. The researchers genetically sequenced the DNA obtained from the rinses and tumour samples to identify those with HPV-positive cancers and determine the HPV type. There are approximately 120 types of HPV, but HPV 16 is one of the two most common associated with cancer. The analysis revealed 44 patients with HPV 16-positive tumours and found that these patients were more likely to have continuing oral HPV 16 infections both before and after cancer treatment. While this study did not link the continued post-treatment infections to tumour recurrence, it was noted that patients with high-risk oral HPV infections prior to therapy, maintained high rates of infection after completing therapy. The team plans further, long-term research to determine if this continued infection leads to cancer recurrence. In 2000, Gillison identified HPV-positive head and neck cancer as a distinct subtype of the disease and linked it to improved survival. "There is no question of cause," says Gillison. "It has now become a question of tracking the infection over time to identify those at risk of developing cancer or cancer recurrence." See also: CDC Releases First Estimate of Human Papillomavirus-Associated Cancer Data CDC News - November 3, 2008 ......... ZenMaster

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Vaccine Makes Cervical Cancer Control Feasible

Vaccine Makes Cervical Cancer Control in Developing World Feasible Thursday, 28 August 2008 Recent advances in cervical cancer prevention mean that controlling the disease in developing countries is becoming feasible for the first time, experts say. Developments such as highly effective vaccines against the human papilloma virus (HPV) and promising new screening tests provide an unprecedented opportunity to tackle the disease in poor countries. Pap smear screening has largely failed so far, because it is too expensive and too complicated to implement, experts said in a series of papers on the topic unveiled Thursday at the World Cancer Congress of the International Union against Cancer in Geneva. The papers are contained in a monograph published in the journal Vaccine. They present the best global thinking on cervical cancer prevention with vaccination and screening, as well as fresh regional and national research and insights to guide governments and donors in building plans. An independent collaboration of more than 180 leading experts, the monograph evaluates which strategies are most promising and likely to be most cost-effective and affordable and sets out various scenarios for programmes. Every year, about 500,000 women worldwide are diagnosed with cervical cancer and more than 250,000 die from the disease. It is the leading cancer in women in half the countries of the world and mostly affects relatively young and poor women. About 80%of cervical cancer deaths occur in developing countries. "Recent estimates indicate that if trends continue the way they are, developing countries will face a 75% increase in the number of cervical cancer cases because of growth and aging of the population in the next two decades. But it doesn't have to turn out that way," said the coordinator of the monograph, Professor Francesc Xavier Bosch of the Catalan Institute of Oncology in Barcelona, Spain. "The discovery of HPV as the cause of cervical cancer has shaken a field that was stagnating and we are now in a new era where developing countries no longer have to be left behind." The monograph presents the first broad analysis of the cost-effectiveness of introducing HPV vaccination and new screening methods into the hardest hit regions of the world – Asia-Pacific, Latin America and the Caribbean. The benefits varied, depending on the size and make-up of the population and the burden of cervical cancer in each country. Future monographs will address the situation in Africa, the Middle East and Eastern Europe. The experts determined that in the Asia-Pacific region, which accounts for more than half of the world's cervical cancer cases, vaccination would be cost-effective – even in the poorest countries – if the cost per vaccinated girl was US$10 - US$25. For Latin America and the Caribbean, the cost per vaccinated girl, including delivery and logistics costs, would have to be less than US$25 to be cost-effective for all countries. In the most developed populations in the region, vaccination would be cost saving if the cost per vaccinated girl is between US$25 and US$60, and cost-effective at higher prices. "Efforts are needed now to adapt the current price of the vaccines so they meet what individual countries can afford; the solution may be tiered pricing according to gross national income per capita and according to the scale of country efforts," Bosh said. Currently the vaccine's price in the private sector is about US$120 per dose, or US$360 per vaccinated girl. Many countries will need subsidies for some time. The monograph also presents updated evidence on the efficacy of various new screening alternatives compare to Pap smear testing. In addition, a discussion of innovative funds mechanisms for bringing HPV vaccination to poor countries, such as the sale of highly rated vaccine bonds to investors. New screening methods that are increasingly proving themselves in pilot studies provide viable alternatives to pap smears for the first time, the experts said. One such method, known as visual inspection with acetic acid, or VIA, involves painting the cervix with vinegar. It is an attractive alternative because it is cheap, seems to be very effective in detecting pre-cancerous lesions, entails only one visit and a simpler treatment that can be performed by nurses immediately and is less dependent on having a strong health infrastructure. A recent large study in India showed a significant reduction in cervical cancer cases and deaths in areas using VIA. Testing for HPV DNA is also a recent screening advance considered important for the developing world, especially as new rapid test kits being developed especially for poor countries are expected to be cheaper and easier to use. Studies have consistently shown that HPV testing works better than Pap smears as the primary screening test because it is better at picking up suspicious cases. "The models provide a useful roadmap for testing promising strategies in the field. More research is needed to determine an efficient combination of these new approaches and each country will have to decide which is best for them, but we are confident we have provided a valuable starting point for going forward," Bosch said. For the near future, the experts say, both vaccination and screening will be needed. However, in the beginning, many countries may have to continue to focus on screening alone until the vaccine becomes more affordable, the experts added. The price of the vaccine and the support for massive vaccination campaigns is one of the biggest barriers for the moment, but several other challenges lay ahead, the experts said. Those include generating the political support for an intervention whose payoff is two or more decades away, cultural acceptability of the vaccine and monitoring the circulating virus. Uncertainties that may affect the success of vaccination programmes include the duration of protection and whether booster shots might be needed, and whether the vaccines will be as effective in girls whose immune systems are suppressed by either malnutrition or other chronic infections such as HIV or malaria. To accelerate progress, advocates are launching a string of initiatives. At this week's conference in Geneva, three major advocacy groups – the International Union against Cancer, Cervical Cancer Action and PATH – announced an unprecedented coordination of public education campaigns. The groups plan to unveil a dossier of more than 400 letters, editorials and declarations from both developed and developing countries, global leaders, cancer control specialists and international organizations that call for improved cervical cancer prevention in the developing world. The International Union against Cancer also announced the launch of a series of professional training workshops on cervical cancer in developing countries, as well as funding for fellowships at leading institutions. Action is also being stepped up elsewhere. In June, the board of the GAVI Alliance, a partnership of public and private agencies focused on bringing vaccines to developing countries, included cervical cancer in its portfolio of priority diseases. The Alliance is now evaluating the introduction strategy and costs of HPV vaccines. In Africa, a network of first ladies was launched last month, with a meeting planned for next year, to further the cervical cancer agenda on the continent. Access to the Vaccine monograph will be free to developing countries and its contents will form the basis of a distant learning programme that includes tutoring for professional education. "This new era of cervical cancer presents many opportunities and challenges ahead. There is now realistic hope for controlling this disease where the toll is the highest and we have to seize this opportunity. We in the cervical cancer community will be stepping up all our efforts to help developing countries get this disease under control," said Isabel Mortara, executive director of the International Union against Cancer. ......... ZenMaster

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