Articles filed under 'MEDICAL DISCOVERIES'
Some tumors of the prostate do not respond to standard hormone therapy. Now there is a new drug on the horizon that appears to slow the growth of difficult-to-treat tumors. Two small studies have yielded promising results.
In the first of these studies, a drug called abiraterone shank tumors by 30% in one-fourth of 31 men whose prostate cancer did not respond to standard therapies and continued to grow. In 35% of the patients taking the experimental drug, their tumors stopped growing.
Standard PSA (prostate-specific antigen) measurements were able to give accurate indications of each man’s response to the new treatment. PSA levels after 12 weeks of treatment with abiraterone lowered PSA levels by 50% or more in 71% of the patients. In two men, the PSA fell so dramatically, it was undetectable.
A leading medical authority at the Cedars-Sinai Medical Center in Los Angeles’ Radiation Oncology Department called abiraterone “currently the most promising prostate cancer drug on the horizon.” He explained that the new hormone therapy appears to be active in men not responsive to other hormone treatments.
Abiraterone works differently from other hormone treatments in wide use today. The new drug targets an enzyme called CYP17 that is needed to produce male hormones throughout the body. Current hormonal treatments can only prevent production of male hormones in the testes. Other parts of the body are still able to produce testosterone and related hormones called androgens that fuel the growth of prostate cancer.
The first study involved men who were initially treated surgically or medically to prevent testosterone production in the testes. None had received chemotherapy, sometimes administered when the cancer does not respond well to hormone therapy. Men in the study took abiraterone orally once a day and generally tolerated the drug without serious side effects.
In a second study, men who were given chemotherapy after their hormone treatment no longer worked showed similar encouraging results after taking the experimental drug. Cougar Biosciences is the manufacturer of abiraterone, and they funded this study.
Researchers have begun enrolling men in a larger and longer study. Patients will be randomly assigned to abiraterone or a placebo (sugar pill). If results continue to be promising, the company will apply to the FDA for approval of the drug. Unfortunately, these studies and the approval process can take several years.
In the U.S., prostate cancer was diagnosed in over 180,000 men and 28,000 men died of the disease in 2008. It is the second most common cause of cancer death in the U.S.
Source: WebMD Health News; 3/1/09 written by Charlene Laino and reviewed by Louise Chang, M.D. blog article by Anna Dabney
March 2nd, 2009
The most recent of several studies involving women who had breast cancer and who also take drugs to strengthen bone shows encouraging results. The study of 1,800 women, published recently in the New England Journal of Medicine, involved those who took hormonal therapy to block estrogen production that fuels growth in certain breast cancers. Half of the group was also given zoledronic acid, or Zometa, intravenously twice a year for three years. Women given Zometa showed a 36 percent reduction in cancer recurrences and metastases, compared to half the group who didn’t get it.
Four years later, 54 women receiving zoledronic acid and 83 who didn’t get the bone drug had a recurrence, a new cancer in the second breast, or a spreading of cancer to the bone. The question is, shouldn’t all women on hormonal therapy for breast cancer receive Zometa or a similar bone drug? Before prescribing these drugs as standard therapy, researchers plan to examine results from two other large studies now nearing completion. Women taking hormonal therapy are blocking estrogen production, which in turn can cause thinning of bones. Why not add the bone-building drugs to their anti-cancer therapies?
Cancer cells are known to interact with a type of bone cell called osteoclasts, whose role is to break down bone. Breast cancer cells sometimes migrate to the bones and stimulate osteoclasts, which in turn stimulate cancer cells. It’s a vicious cycle. But what if the cycle can be interrupted?
Drugs used to treat the bone-thinning disease osteoporosis have been shown to stop osteoclasts from releasing substances that cause bone loss. As osteoclasts stop working, they die. Other studies of bisphosphonates to prevent osteoporosis have shown in lab studies that they might have other anticancer effects. Bisphosphonates affected the ability of cancer cells to stick to surrounding tissue, to invade and grow in numbers. One of the new study’s lead researchers believes that bisphosphonates could squelch the cells that migrate to the bones and hide in marrow, thus affecting the ability of breast cancer to recur.
Researchers are also investigating whether bisphosphonates could treat cancer that has already metastasized to bone. After determining that they could, zoledronic acid and other bisphosphonates were approved for women with bone metastasis. These therapies were shown in one study to prevent further spread of cancer in bones. Zometa is approved only for bone complications of cancer and is not an official drug for osteoporosis. There is a rare but quite serious side effect, osteonecrosis of the jaw, which has been seen with bisphosphonate use. No instances have been seen in study participants, however.
Studies are still in progress to investigate whether these bone drugs used in high doses to treat cancer can prevent breast cancer from initially spreading. Results have been mixed. In research now ongoing, there is hope that zoledronic acid could add a benefit to existing breast cancer therapy to the same degree as the magnitude from chemo or hormonal therapy alone. Scientists and physicians are waiting for data from other studies. Clinical trials may have the answers in the near future.
Source: Gina Kolata; New York Times; Feb. 11, 2009
http://www.nytimes.com/2009/02/12/health/research/12bone.html?th&emc=th
blog article by Anna Dabney
February 16th, 2009
A study at the University of Minnesota indicated that persons who gave one of their kidneys lived a normal life span and were as healthy as those in the general population. The four-decade study of 3,700 donors is the largest, longest study to examine long-term outcomes. Having one kidney did not raise the risk of kidney failure later in life. Rates of kidney failure were found to be even lower in donors than in the general population.
Findings were published in the January issue of the New England Journal of Medicine. A transplant surgeon from the University Maryland, not involved in the research, greeted the news with enthusiasm. He called this study “a confirmation that living donation is a safe thing.”
Most former donors tested in this study showed good kidney function and enjoyed an excellent quality of life. Researchers attributed their good, long-term outcomes to the rigorous screening criteria originally used to pick donors. Those who elected to give a kidney were required to be healthy and have no kidney problems, high blood pressure or diabetes. The last two factors are main causes of kidney disease.
Kidneys filter waste and excess fluid from blood. Patients with kidney failure have only two options: dialysis or a kidney transplant. The national waiting list is long, with more than 78,000 waiting for a donor with the right matching characteristics. Today, with the rising incidence of obesity and diabetes, the need for donor kidneys has climbed dramatically.
Researchers recognize the sacrifice made by kidney donors. Their generosity of spirit will not go unrewarded if at some time in the future the kidney donor needs a transplant. Those individuals would be given priority on the waiting list.
Study donors were primarily white and younger than the donors of decades later. Results found in this group may not apply to populations donating a kidney today. The main value of this reassuring study is its large size and duration. Living donation has increased in recent years as more people have become willing donors and newer surgical techniques have shortened recovery time. In 2007, nearly 17,000 kidneys transplanted in the U.S. came from living donors.
Source: original article by Stephanie Nano, Associated Press; San Francisco Chronicle and Oakland Tribune on January 29, 2009. (blog article by Anna Dabney)
January 29th, 2009
For those who have experienced chemotherapy, or watched their loved ones go through it, the idea of an effective cancer treatment with NO side effects seems like a dream come true. Dreams can be a long time in coming, however. The brain child of American inventor John Kanzius may one day be the answer to the prayers of cancer patients. First, his Kanzius Machine must be rigorously tested in laboratory animals before clinical trials are approved for cancer patients. Preliminary lab testing has shown great promise.
The potential new treatment that Kanzius envisioned was featured on CBS’ “Sixty Minutes” (April 13, 2008). In theory, it involves gold or carbon nanoparticles injected into the bloodstream or into a cancerous tumor. These metallic-laced nanoparticles, already FDA-approved, attract radio waves. Once the diseased cells are properly targeted, radio waves would heat them to an optimal temperature to eradicate them. The idea is to destroy cancer cells, leaving healthy cells undamaged. Nanoparticles are so tiny that trillions of them can be contained in a test tube. The chief problem is finding a delivery system in which the nanoparticles would bind only to cancer cells.
How did a man without a medical degree or credentials as a lab scientist come up with a revolutionary idea to treat cancer? Diagnosed with liver cancer six years ago, John Kanzius had endured thirty-six rounds of chemotherapy. During his treatments at a renowned cancer center, he was touched by the faces of young cancer patients, children with teddy bears, fighting for their lives. It was then that he vowed to try to find a better way to fight cancer.
One sleepless night, the retired radio and TV executive envisioned using radio waves to treat cancer. In his childhood, he had built radio sets. He understood that radio waves could harmlessly pass through a living organism but were attracted by metal. Once his primitive tests showed promise, the senior citizen built radio-wave equipment and conducted experiments in his garage. He invested $200,000 of his own money to build prototypes of his radio frequency (RF) equipment. Support and funding for his efforts have since materialized from many sources. His Kanzius RF Machines are now selectively placed in laboratories at the University of Pittsburgh and at MD Anderson Cancer Center in Houston, Texas.
At MD Anderson, Dr. Steven Curley, a surgical oncologist, began to work closely with Kanzius on his invention. Dr. Curley believes the potential treatment to be the most exciting new development he has seen in twenty years of working in oncology. Like an “ultimate weed killer” able to kill weeds without harming grass, the treatment is designed to destroy only the cancer cells. The ability to eliminate solid tumors injected with gold nanoparticles has already been demonstrated in rats and rabbits. The ultimate goal is to be able to target microscopic cancer cells that have circulated throughout the body. Curing metastatic cancers would not be possible without such a selective delivery system. If a way is found to precisely target and destroy only cancer cells, then the potential to cure many types of cancers is tremendous – and with no pain and distress.
John Kanzius is working with the Lee Memorial Health System in southwest Florida to coordinate tentative clinical trials after approval is granted. He hopes to live to see his dream realized some three or four years down the road.
Sources:
http://en.wikipedia.org/wiki/Kanzius machine; http://60minutes.yahoo.com/segment/159/the_kanzius_machine
April 17th, 2008
A hip fracture, one of the most dreaded injuries, can be devastating and complicated. This medical emergency is a painful, stressful and life-changing event. One in five persons over age 50 who breaks a hip will die within a year. Forty percent of hip-fracture patients over age 65 move to a nursing home after hospitalization.
The risk of a hip fracture rises with age. Those with brittle bones (osteopenia or osteoporosis) are most likely to suffer a hip fracture from falling, or in some cases, just the stress of walking can cause the femur to snap. Protective reflexes in older adults are slower and make it more difficult to avoid falling directly on a hip. In addition, certain medications, such as SSRIs and oral corticosteroids, may increase fracture risk.
A few people are “fortunate” enough to have stable fractures so that they are able to avoid surgery and move around after a few days of rest. The majority of hip fracture patients undergo surgery within 24 hours of being admitted to the hospital. Hip fractures can sometimes heal without surgery after up to three months of bed rest. However, prolonged immobility can lead to complications such as pressure sores, deep vain thrombosis (DVT), and muscle loss. The risk of DVT can be reduced with pressure stockings and blood-thinners, but the best protection involves getting up and moving around as soon as possible after surgery. Any unusual heat, pain and swelling in the leg can indicate that DVT has developed, during which a clot can travel to the lung or brain.
Recovering the ability to walk is unlikely following several months of bed rest. Because urinary catheters must be used when the patient is confined to bed, urinary tract infections are an additional risk. Catheters should be removed as soon as possible. If the patient is immobilized for long periods, pneumonia may set in. Delirium can be another complication to watch for, including delusions, agitation and hallucinations. Less subtle symptoms and more commonly seen are impaired ability to focus, disorientation, and memory and language problems. These symptoms may be overlooked due to heavy sedation for pain and in those suffering from dementia.
The prognosis for recovery is best in cases where hip surgery is an option. The type of hip surgery is determined by the location of the fracture. Surgery is the beginning of the long road to recovery. Only the patient can do the painful and difficult work of rehabilitation, which starts as soon as possible after the operation. Physical therapists help the patient to walk to a chair and use the bathroom. Therapy progresses to include exercises to strengthen muscles and learning to use a walker and a cane.
The patient may go to a rehab center for two weeks, followed by several months of outpatient therapy. Not everyone is able to return home after rehabilitation is completed. Some go to a nursing home and continue their physical therapy before they are able to return home. Others may need to stay there permanently to receive the support the need.
Living at home after a hip fracture can be complicated and difficult for all concerned. Pain and setbacks can impede the recovery process. The home environment should be modified in order to make it easier for the patient to function and remain active while minimizing pain. Soreness can persist for a month or longer, and the individual can quickly lose strength if not strongly motivated to continue exercises learned in rehab. Depression can also sap the desire to continue rehabilitation.
Caregivers should understand that the hip fracture patient has a high risk of a second fracture. In many cases where thin bones are involved, the physician will prescribe life-long osteoporosis therapy to strengthen bones and reduce risks of future falls and fractures. It is vital that the patient also gets adequate calcium intake – 1,200 to 1,500 mg daily for people over 50 and vitamin D of 800 IU daily. Calcium and vitamin D strengthen bones and lower the risk of falling again.
Seniors can do a great deal to avoid the pitfalls of a hip fracture. For those with thinning bones, osteoporosis therapy and Calcium can help as preventive measures. Getting adequate exercise, using hand-held weights to build bone, and working on balance are also useful. Those who are unsteady on their feet should have a walking companion and use a cane. Obstacles such as loose throw rugs should be removed from the home. When exercising outdoors, walking on an even surface can help to prevent tripping and falling.
Johns Hopkins Medical Letter: Health After 50; August 2007
April 9th, 2008
Over the past six months, I took a breather from writing blog articles for Healthcareupdates.com. During that period, I put more effort into my personal writing which includes poetry and my autobiography in progress. I also served as chief copy editor for my daughter, who just completed her doctoral dissertation.
For relaxation, I took three special trips. I attended my high school reunion out of state, celebrated my birthday with my grown children, and took a cruise to Mexico’s Yucatan Peninsula. I’m now back and looking forward to again summarizing the latest trends in healthcare, as I see them. I encourage comments or questions from my readers.
April 8th, 2008
In recent years, several large studies have shown that quicker and cheaper “virtual colonoscopy” is a viable alternative to traditional colonoscopy. Although still considered “experimental” and not covered by most insurance for routine screening, the noninvasive X-ray procedure is available for those willing and able to pay the $1,100 cost. Traditional colonoscopy, the “gold standard” for many years, costs roughly $3,000.
Colonoscopy is recommended for persons 50 and over, but most don’t get them unless they are symptomatic. Instead, a sigmoidoscopy may be offered which checks only the lower bowel or intestine by inserting a flexible tube. Perhaps the most unpleasant part of any technique to explore the colon for polyps is drinking laxatives or using enemas to purge the bowel before the procedure.
Colon cancer is the second leading cause of cancer death in the U.S. and is largely avoidable by detecting and removing small polyps before they grow and become cancerous. Each year about 52,000 Americans die of the disease.
The latest study compared two groups of approximately 3,000 persons in each group. One group received traditional colonoscopy and the second one the virtual procedure. Approximately the same number of advanced polyps were found in each group (123 compared to 121).
With virtual colonography, a CT scanner takes a series of X-rays of the colon and creates a computerized 3-D image. A small tube is inserted in the rectum to inflate the colon for better viewing. There is no sedation or recovery time. If polyps are seen, they cannot be removed using this technique. Any significant polyps are then removed the same day using a traditional colonoscopy.
In traditional colonoscopy, a gastroenterologist uses a flexible, thin tube and snakes it through the large intestines. Any polyps spotted are removed in the process. There is a tiny risk of a perforated colon using the traditional procedure, and prompt surgical repair is needed.
The virtual colonoscopy avoids sedation and the risk of colon perforation, but the patient is exposed to radiation. In addition, small, benign polyps cannot be removed. They must be watched and will need to be removed if they grow significantly or become malignant.
If colon cancer screening guidelines are changed as is expected, virtual colonoscopy may be covered by insurance companies in the future. The less invasive procedure may encourage more patients to get checked when they should. Usually, intervals of ten years between examinations are recommended if no polyps are found.
Source: MSNBC
October 8th, 2007
A new test for prostate cancer, believed to be much more accurate than the PSA test, is expected to be approved soon. The test, currently undergoing large-scale clinical trials, measures the blood protein EPCA-2. Not only can it detect prostate cancer more effectively than measurement of prostate specific antigens (PSA), it also can determine the aggressiveness of the cancer and whether it has already spread.
In recent studies of 385 men, those with elevated EPCA-2 test results were found to have cancer 94% of the time, compared with 19% of those showing elevated PSA results. Only 3% showed false positive results and about 6% of existing cancers were missed using the new EPCA-2 blood protein markers. These results compare more favorably than the PSA test, which misses about 15% of existing cancers and gives a high level of false positives.
Every year, about 1.6 million men have unnecessary biopsies because of elevated PSA scores, whereas only about 230,000 of them actually are shown to have cancer. The digital rectal exam (DRE) is also not definitive in detecting this common cancer of men.
Prostate cancer is diagnosed in 230,000 new cases annually, and about 27,000 men die of the disease. The current PSA and DRE detection procedures are also deficient in that they cannot distinguish between cancer’s aggressive form, which is frequently fatal, and a slow-growing variety where “watchful waiting” may be the best strategy.
The new test could revolutionize the treatment of prostate cancer. It could save many lives and spare men with the slow-growing form of cancer from having unnecessary treatments in the future. Its manufacturer Onconome Inc., a Seattle Biomedical company, is developing the EPCA-2 test and expects the FDA to approve it by early next year.
Source: San Francisco Chronicle; Sunday, April 26, 2007; reporter Susan Brink of the Los Angeles Times
May 10th, 2007
The artificial hip is indeed a medical miracle, but the joint replacement surgery usually lasts only 20 years or so. Each year about 300,000 Americans undergo hip joint replacement surgery. As younger patients avail themselves of this type of hip surgery, the problem of “outliving” the joint replacement must be faced.
Middle-aged or younger people with hips damaged by disease or injury are often cautioned to put the surgery off as long as possible. In the meantime, many are plagued with pain and disability.
Now, an alternative surgical procedure may make the waiting game a thing of the past. Because extracting and replacing a worn-out or defective artificial hip is difficult, more surgeons are turning to hip resurfacing. Surgeons using this procedure preserve enough of the healthy bone to allow for a future total hip implant when benefits of hip resurfacing wear out.
In the past decade, tens of thousand of patients worldwide have undergone hip resurfacing. Many U.S. “medical tourists” had the procedure done overseas, where doctors are experienced in the technique and costs are lower. Popular destinations are Britain, Belgium or India, where costs may be half what they are in the U.S.
Hip resurfacing surgery is no easier for the patient or physician than hip replacement, and the incision is usually larger than with a total joint replacement. Complete healing can take six months or longer. The advantage is that the patient will still be eligible for a total hip replacement using an entirely new artificial joint rather than having a revision of the old one.
Hip resurfacing and total hip replacements both involve implanting a metal cup in the pelvic socket. The difference is mainly the way each procedure treats the top of the femur, the long thigh bone that fits into the socket. In resurfacing, the femur is shaved to a rounded shape and covered with a metal cap, with a spike that is cemented into a small hole drilled into the center of the femur.
With total hip replacement, surgeons saw off the entire head of the femur and replace it with a larger, hemispherical device that is anchored with a much longer spike and driven deeper into the femur. This procedure leaves too little strong bone to allow for follow-up with an entirely new total hip replacement if this joint wears out.
Hip resurfacing is not minor surgery. It requires a highly skilled surgeon, and the operation usually takes a bit longer than the three or four hours of total hip replacement. In addition, patients lose more blood, although transfusions are rarely needed.
With either procedure, problems can occur, but they are unlikely. Complications that are possible with either surgery include infections or fractures. Since hip resurfacing is so new, we are unlikely to know how durable the resurfaced hips are until the 20-year mark is reached in the earliest patients.
Doctors advise patients, especially younger ones, not to even think about either procedure unless they are in pain every day. Most people won’t want to take on the risks of either type of surgery, and the complications that could arise, just to improve their golf game or to be able to resume jogging.
Source: New York Times
April 16th, 2007
Researchers in Germany have used a technique called diffusion tensor imaging (DTI) in a study that examined brains of healthy volunteers and those with chronic back pain. They discovered that the brain in patients with chronic back pain had a more complex, active microstructure in regions associated with pain-processing, emotion and stress response.
The study findings were presented at the annual meeting of the Radiological Society of North America, held in Chicago recently. Researchers indicated that DTI demonstrates chronic pain is real and could help treatment research. Patients who suffer back pain sometimes have difficulty convincing their physicians, relatives, and insurance carriers of their genuine distress. Spinal MRI images do not always clearly demonstrate the source of pain.
According to the lead researcher, a radiologist in Munich, Germany, the objective and reproducible correlates in brain imaging should change the way chronic pain is perceived. It need no longer be a subjective experience. For pain diagnosis and treatment, the consequences could be huge. As a result, clinicians may direct therapeutic attention from the spine to the brain.
What is unclear is whether the brain in certain individuals is predisposed to developing chronic pain, whether ongoing pain causes hyperactivity and change in the brain’s organization or a combination of both.
Physicians who treat patients with chronic back pain have long known that chronic pain can begin with a serious injury. Even after healing has occurred, the brain continues to send pain signals for these individuals. The new imaging technology DTI will be able to validate their theory that the nervous system has been “rewired.”
This study adds to the growing body of research showing that chronic pain is associated with physical changes in the brain. Chronic is defined as lasting more than six months.
In some cases, back pain plagues individuals for many years after their initial injuries.
This study helps the medical community to understand how the central nervous system is involved in back pain. More research is needed to determine what the brain’s physical changes mean and how to most effectively treat the pain.
Source: BBC News
February 20th, 2007
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