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Genetic Markers Identify Probability of Lung Cancers Recurrence

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Genetic alterations in tumors and tissue taken from early-stage lung cancer patients are clear pointers to which cancers might recur. Researchers say the findings could change the approach to treating even the smallest lung cancers—the size of a pea—which are known to recur within five years in 30 to 40 percent of patients.

"This is DNA forensics for cancer," says Malcolm Brock, M.D., associate professor of surgery at Johns Hopkins. "While there may be no trace of cancer that we can spot after surgery with a microscope, the DNA evidence from these tumors may have been left at the scene, especially in lymph nodes."

The research team from Johns Hopkins Kimmel Cancer Center identified methyl groups that connect with the DNA structure of a gene. The development of cancers signals cells to switch certain genes on or off, and methylation is a common phenomenon in this process. Disruption to these signals may create abnormal proteins that lead to cancer or its recurrence.

In the study, Brock and his team checked more than 700 surgical samples from 167 early stage non-small lung cancer patients, looking for specific methylation patterns linked o cancer. For 51 patients, whose cancers recurred within 40 months, tumor and lymph node tissue was compared with samples from the remaining 116 patients whose cancer did no recur. The scientists tested all the samples for methylation on seven genes linked to the development of lung cancer. Four of them—p16, H-cadherin, APC and RASSF1A—showed the highest amounts of methylation in patients who had a recurrence of the cancer.

For many of the genes, the study revealed a twofold difference in methyl marks between recurrent cancers and those that did not return.

"The DNA evidence we see for many of the recurring cases suggests it may be wise if our work is confirmed to reclassify such cancers as advanced disease instead of early stage," says Brock.

Higher than normal methylation, combining two genes known as p16 and H-cadherin located in both tumor tissue and a lymph node remote from the tumor area, meant that cancers returned faster than average in 11 patients. For 8 of them this methylation pattern had cancers returning within a year; for the remaining 3 it took 30 months for the cancers to recur.

When analyzing the results to quantify the odds on a patient’s cancer returning, they noted a 5 to 25-fold in risk depending on the particular methylation pattern. While the small sample size meant that some of the gene markers lacked statistical significance, they believed that odds predictions were valid for p16 and H-cadherin.

Kimmel Cancer Center medical oncologist James Herman, M.D. says if these results are confirmed, it may lead doctors to consider treating high-risk patients more aggressively with chemotherapy after surgery. He also believes that therapies which target these gene patterns by stripping off methyl groups hold promise as well. "These marks of aggressive disease also are themselves targets for therapy."

The study appeared in the March 13 issue of the New England Journal of Medicine.

Researchers Find that Head and Neck Cancers May Be Different Diseases

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Different risk factors for head and neck cancer have been identified by researchers at Johns Hopkins Kimmel Cancer Center, raising the possibility that they are different forms of these diseases.

Head and neck tumors caused by the human papillomavirus (HPV) were generally associated with sexual behaviors and smoking marijuana, rather than tobacco and alcohol. It was also found that people with the viral-linked cancer were mostly white, younger, married, and college-educated with income of $50,000 or more. Those not attributable to HPV were associated with tobacco, alcohol and poor oral hygiene, most generally listed as the causes of head and neck cancer. The findings are to be published in the March 12 issue of the Journal of the National Cancer Institute.

"Our results indicate that HPV-positive and HPV-negative head and neck cancers have different risk-factor profiles and should be considered two distinct diseases," says Maura L. Gillison, M.D., Ph.D., an associate professor of oncology and epidemiology at Hopkins. "They just happen to occur in the same place."

HPV infection has been seen in up to 72% of patients, and is associated with the development of some neck and head cancers, mostly in the upper throat and back of the tongue. Gillison noted that the incidence of HPV-linked cancer has nearly doubled over the past 30 years, and that head and neck cancer patients with HPV-positive tumors are mlore responsive to treatment and survive longer than HPV-negative patients.

According to Gillison, the American Joint Committee on Cancer is now considering incorporating HPV status in its guidelines for determining clinical stages of head and neck cancer.

For this study, 240 patients at the Johns Hopkins Hospital with head and neck squamous cell carcinomas were studied between 2000 and 2006, to identify HPV-positive or negative tumors. All study participants completed a computerized interview that asked questions about their risk factors.

Source: Journal of the National Cancer Institute, March 12, 2008

Infection Expert Warns That MRSA May Be Unstoppable

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Dr. Ron Najafi, CEO of NovaBay, describes MRSA (methicillin-resistant Staphylococcus aureus) as a slow-moving hurricane. "Once the ‘superbug’ hits a community or hospital," asks Dr. Najafi, "are populations ready to deal with it?"

His comment was prompted by the untimely death of college student Chris Steden to the disease, which infects 90,000 Americans in our hospitals every year, with 19,000 deaths reported annually.

The company is working on a compound, NVC-422, which may successfully fight many pathogens including MRSA. S. aureua breeds in the nose and on the skin. NovbaBay’s AgaNase formulation of NVC-422 for nasal applications, is an anti-infective, but not a conventional antibiotic. Topically applied to the lower nasal passage to eliminate colonization of S. aureus, including MRSA, AgaNase rapidly destroys a range of pathogens that include bacteria, yeast, and viruses.

Source: NobaBay Pharmaceuticals

Pandemic Flu Can Be Controlled Pending Availability of a Vaccine

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Prompt use of social-distancing measures, antiviral treatment and prophylaxis could control an outbreak of pandemic influenza in the United States, pending the availability of a vaccine, according to a recently-published study.

Three teams of researchers in the U.S, and England, in close collaboration with Government officials, studied various intervention combinations to guide national pandemic planning. The three research teams and an informatics group that participated are part of the Models of Infectious Disease Agent Study (MIDAS) Network, an effort funded by the National Institute of General Medical Sciences, or NIGMS.

"The federal government wanted three separate infectious-disease-modeling groups working on the same problem just to make sure the results were robust, since this data would be used to inform national pandemic planning," said the study’s co-author, Ira M. Longini Jr., Ph.D. "We got the highest level of input."

The researchers concentrated on assessing the effectiveness of a blend of antiviral and social-distancing interventions (like closing schools) in preventing a flu pandemic, since a vaccine was unavailable at the time. Other studies had shown that a vaccine would be very helpful in slowing a pandemic.

"The good news was that all three of the disease-modeling groups involved in the study found that an outbreak of pandemic flu similar to the pandemic of 1918 could be mitigated if these measures were implemented quickly," said M. Elizabeth Halloran, M.D., D.Sc., the study’s lead author.

To conduct the study, the researchers used three separate but similar computer models to calculate the spread of influenza within a population similar to that of Chicago, with approximately 8.6 million people. Members of this virtual community interacted the way people normally do: within households, schools and workplaces, and the community at large. All three models were set up to have attack-rate patterns similar to those of past U.S. flu pandemics.

Predicting the spread of an infectious disease such pandemic influenza requires much more than simply connecting dots on a map. Instead, Halloran and colleagues rely on a tool called stochastic modeling to take into account real-world unpredictability, as well as many factors about the disease and the affected population. In constructing these models, the researchers begin with assumptions about how people interact and how the virus spreads. They also introduce and evaluate the effectiveness of various intervention strategies.

These were the findings published in the online Early Edition of PNAS, a publication of the Proceedings of the National Academy of Sciences of the United States of America. M. Elizabeth Halloran, M.D., D.Sc., was the lead author, Ira M. Longini Jr., Ph.D., was the co-author. Both are researchers at Fred Hutchinson Cancer Research Center and professors of biostatistics at the University of Washington, and use mathematical and statistical methods to study the natural course of infectious diseases. Prior to publication, Longini presented the findings at the White House and at the Institute of Medicine.

X-Ray Often Better and Cheaper than MRI in Knee Diagnostics

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A weight-bearing X-ray is a better diagnostic tool and much less expensive than the MRI typically prescribed for patients with knees affected by osteoarthritis, according to a recent study. A patient’s medical history and a routine physical should be the starting point for a primary-care physician, followed by basic diagnostics.

"MRIs are being used in excess. Many doctors no longer talk to or examine their patients. Instead, they are going right for the technology," said Wayne Goldstein, MD. Dr. Goldstein, lead author on the study, is a clinical professor of orthopedics at the University of Illinois at Chicago College of Medicine and chairman of the Illinois Bone and Joint Institute.

"This is another example of over-utilization of the health-care system. It has become easier to go for the high-cost imaging. On average, an X-ray can cost less than $150, while an MRI can cost around $2,500". Medical imaging now accounts for 10%-15% of Medicare payments to physicians, compares with less than 5% only 10 years ago.

In 2008, Medicare will reimburse doctors more than $400 per MRI. By contrast, a 4-view X-ray which effectively reveals osteoarthritis and is routinely used by most orthopaedic surgeons, reimburses doctors just over $43. It is estimated that these MRI costs will continue to row at an annual rate of 20% or more in 2008. In the United States more than 533,000 total knee replacements were performed in 2005, primarily because of severe pain, swelling of stiffness of the knee caused by osteoarthritis.

A random sample of 50 knee arthroplasty patients found that 32 of the 50 had had a knee MRI within 2 years before surgery, ordered by their primary-care or orthopedic physician. The MRI did not produce any diagnostic information which could not have been provided by an X-ray, and more than 50% did not have any X-rays before surgical consultation.

"There are some indications for MRI, such as suspicion of avascular necrosis [in which blood loss to the area causes bones to break down, something which may not be seen on early X-rays], but that is not a common condition," Dr. Goldstein said. Dr. Goldstein and his co-authors believe that the main reason for this over-utilization of the MRI is a lack of education on this diagnostic technique, especially with family and primary-care physicians.

Dr. Goldstein added, "We fix this problem through educating physicians on the appropriate use of MRIs. We also need to educate our patients. Virtually every adult experiencing a knee problem should first have an appropriate set of X-rays before considering an MRI, which has been marketed as the premier diagnostic tool, so patients often come into the office expecting, even demanding, an MRI. Physicians need to look at why they are ordering an MRI and consider whether it is truly necessary."

The study was presented at the 75th Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) in March, 2008.

Increased Risk of Breast Cancer Recurrence Tied To High Levels of Estrogen

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Women whose breast cancer returned after treatment had almost twice as much estrogen in their blood than did women who remained cancer-free, according to a newly published study.

The study’s lead author, Cheryl L. Rock, Ph.D., a professor in the Department of Family and Preventive Medicine at the University of California, San Diego, said that high levels of estrogen—which lead to the initial development of breast cancer—could be associated with an increased risk of recurring cancer.

"While this makes sense, there have been only a few small studies that have looked at the link between sex hormones in the blood and cancer recurrence," she said. "This is the largest study to date and the only one to have included women taking agents such as tamoxifen to reduce estrogen’s effect on cancer growth."

"What the results mean for women who have already been treated for breast cancer is that they should do as much as they can to reduce estrogen in their blood, such as exercising frequently and keeping weight down," she added. "Taking anti-estrogen drugs like tamoxifen may not completely wipe out the hormone’s effect in women who have high levels of estrogen."

The Women’s Healthy Eating and Living Study (WHEL) provided participants for the breast cancer study, a dietary intervention trial that monitored 3,088 women treated for breast cancer but cancer-free when recruited for the study. Subjects were placed in two groups—one that ate a " normal" healthy diet, one that ate extremely large amounts of fruits, fiber and vegetables. After 7 years, participants were checked for breast cancer, which was about the same for each group. Researchers interpreted the findings to mean that a normal diet that incorporates the U.S. Food and Drug Administration guidelines for recommended amounts of fruits and vegetables is sufficient.

In the current study, 153 WHEL participants whose cancer had recurred were matched with 153 participants who remained cancer-free. These pairs were alike in terms of tumor type, body size, age, ethnicity, use of chemotherapy and other variables. Two-thirds of the participants were using tamoxifen, Rock said.

When they enrolled, researchers tested the women’s blood for concentrations of the steroid hormones estradiol (the primary human estrogen) and testosterone. They analyzed different forms of estradiol and testosterone in the blood, such as how much was bound to transport proteins (such as to the sex hormone binding globulin, or SHBG) and how much was "free" circulating and able to enter a cell.

The study was published in the March issue of Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research.

Will There Be Enough Orthopedic Surgeons to Meet Joint Replacement Demand?

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According to a new study by Dr. Iorio and his colleagues to be presented at the 75th Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS), the numbers of hip and knee replacement surgeries have increased dramatically in the last 10 years.

Dr. Iorio, senior attending orthopedic surgeon at the Lahey Clinic in Massachusetts said, "We are preparing for an epidemic of serious proportions."

In 2005, 285,000 total hip replacements and 523,000 total knee replacements were performed in the United States. By 2030, these two procedures are expected to jump to 572,000 and 3.4 million, respectively. Said Dr. Iorio: "The demand for these procedures will grow rapidly, and the orthopedic workforce will not be able to keep up. The supply of orthopedic surgeons will only increase 2 percent during 2000 and 2020. What we have on our hands is an access problem."

A 2005 survey of more than 23,000 AAOS members revealed:

  • 30 percent identified themselves as general orthopedic surgeons
  • 13 percent of orthopedic surgeons identified themselves as specialists in sports medicine
  • 10 percent identified themselves as hand surgeons
  • Only 7 percent identified themselves as primary surgical specialists for the adult hip and knee

"Simply put," Iorio added, "there will be a need for services that overwhelms the supply of physicians who will be able to fill that demand. Patient care is of utmost concern to us. Getting arthritic patients back to the quality of life they once had is always first and foremost. If these projections come to life, the access for a joint replacement will negatively impact patient care."

Is the Information We Have About Pharmaceutical Drugs Really Reliable?

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A report in the current issue of the British Medical Journal questions the reliability of what we know about the latest drugs, such as antidepressants or statins.

The Food and Drug Administration Amendments Act (FDAAA) of 2007 stipulated that the results of clinical trials conducted for a new drug are published in a public database, say journalists Jeanne Lenzer and Shannon Brownlee. Despite this Act, lack of access to reliable data remains an ongoing problem. Not all trials have to be registered, while trade secrecy laws protect other products from providing access to full data.

Data can be demanded under the Freedom of Information Act, but trade secrecy laws allow information about a drug that is not approved for a new indication to be withheld, even though the drug is already being marketed for other indications. The stated purpose of these trade secrets is to prevent a company being placed at a "competitive disadvantage" to other companies.

For example, in 2001 Valdecoxib, a COX 2 inhibitor failed to obtain FDA approval as a treatment for acute pain. Some of the trial information was removed from the FDA website, with the public and medical researchers unaware of possible side effects—a situation that should be remedied at once, say the authors.

One possible solution would be to make the FDA database available to researchers, a move resisted by the FDA which claims that putting all its data online would be too burdensome. But doing this future Freedom of Information requests would be reduced, say the critics. Failing to make trial participant data available to the public has to be accomplished, if the public interest is to be served, say the authors.

Source: British Medical Journal, Volume 336, pp 532-534

Older Adults Can Recover Well from Anterior Cruciate Ligament Surgery (ACL)

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Today, older adults are staying active much longer, making them susceptible to injuries—especially vulnerable to tearing their anterior cruciate ligament (ACL).

A new study presented today at the 75th Annual Meeting of the American Academy of Orthopaedic Surgeons, found that these active baby boomers who undergo ACL surgery are about as likely to return to pre-injury levels of activity as much younger people. These findings have led researchers to conclude that age itself should not be a factor when determining candidates for the increasingly common knee-ligament surgery.

"Twenty years ago we did not see older patients being so active later in life. ACL surgery was rarely considered for people in their 40s and 50s," said Diane Dahm, MD, assistant professor of orthopaedic surgery at the Mayo Clinic in Minnesota."Older patients today want to continue to run, play basketball and be active late into life, so they need a level of knee stability that will support an active lifestyle."

The study followed the recovery of 34 patients aged 50 to 66 for an average of 48 months between 1990 and 2002 following ACL surgery at the Mayo Clinic. Patients with injuries to multiple knee ligaments were excluded.

The study found that after ACL surgery:

  • 83 percent were rated as normal or near-normal
  • 83 percent returned to playing sports
  • patients went from 4.3 before surgery to 8.3 postoperatively on the UCLA ( University of California at Los Angeles), activity score
  • five of the 34 patients required additional knee surgery

"Today’s active baby boomers are pushing the envelope for when people are considered to be too old for ACL surgery," concluded Dr. Dahm."When considering candidates for ACL surgery, people’s fitness levels and their desire to return to an active lifestyle should be taken into account rather than looking at age."

The ACL is one of the most commonly injured ligaments of the knee. The incidence of ACL injuries is currently estimated at approximately 200,000 annually, with 100,000 ACL reconstructions performed each year. In general, the incidence of ACL injury is higher in people who participate in high-risk sports, such as basketball, football, skiing and soccer.

Fractured Shoulder May Lead to Higher Incidence of Broken Hip in Older Women

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Older women who suffer a broken shoulder (proximal humerus fracture) have a high risk for also breaking a hip within a year after the shoulder injury.

A new study presented today at the 75th Annual Meeting of the American Academy of Orthpaedic Surgeons (AAOS), found that after a shoulder fracture a woman’s risk of fracturing a hip within the following year was five times greater. The risk decreased after the first year but still remained elevated.

Understanding the connection between these injuries is important to preventing hip fractures. Hip fractures account for more than 350,000 hospital admissions in the United States and more than 60,000 nursing home admissions each year. Women have greater risk because of their higher susceptibility to osteoporosis.

Statistics show:

  • about 70 percent of hip fracture patients are women
  • more than 4 percent of hip fracture patients die during their initial hospitalization
  • 24 percent die within a year of the injury
  • about half of women who sustain hip fractures lose the ability to walk independently

Preventing hip fracture poses s a significant quality-of-life issue. "Earlier studies have shown that there is an increased risk of hip fracture after a proximal humerus fracture, but our study found that there is a defined window of time in which the risk is much greater than previously thought. Additionally, other research has shown that interventions within the first three months can reduce the risk of subsequent fractures," said Jeremiah Clinton, MD, co-author of the study and acting clinical instructor at the University of Washington, Department of Orthopaedics. "If we maximize our hip-fracture prevention efforts up front, we may have a much better chance of helping the patient avoid a life-changing and potentially life-ending injury."

The study followed a group of older, Caucasian women for nearly 10 years and found that, while 8 percent of women who did not break a shoulder suffered hip fractures, approximately 14 percent of those who suffered a shoulder fracture later sustained a hip fracture.

The strongest risk factors for hip fracture were age and hip bone mineral density. Other factors included:

  • self-reported health status
  • height at 25 years of age
  • history of recent falls
  • impaired depth perception
  • history of prior fractures

Even when controlling these factors, the researchers still found the increased risk for hip fracture in the first year after a proximal humerus fracture. The reasons for the connection between humerus fracture and hip fracture are still unclear. "It may be associated medical problems, limited use of the injured shoulder, or there could be something about the treatment for the first fracture, such as narcotic pain medications, which could have caused the patient to fall and break a hip," Dr. Clinton said. "Now that we are aware of the relationship between these types of fractures, we can take precautions, intervene early and hopefully help to prevent some hip fractures from occurring."