Friday, December 11, 2009

Adding Chemo to Tamoxifen Helps Some Breast Cancer Patients

Adding chemotherapy to traditional cancer-suppressing tamoxifen can increase survival in postmenopausal women with the most normal type of breast cancer, known as estrogen receptor-positive, also it's best given before the tamoxifen regimen starts, according to a new study.
"Chemotherapy with Adriamycin adds to your survival benefit over and above what tamoxifen would do if you are postmenopausal and have the positive lymph nodes and estrogen receptor-positive cancer [the most common type]," explained Dr. Kathy Albain, the lead researcher and professor of medicine at Loyola University Chicago Stritch School of Medicine.
And in another study, Albain found that screening breast tumors with an available multi-gene test spots patients who may not need this form of chemotherapy, despite fitting the standard profile.
Both studies are published online Dec. 10, the first in the journal The Lancet and the second in The Lancet Oncology. Albain is also due to present her findings Thursday at the annual San Antonio Breast Cancer Symposium in San Antonio, Texas.
In estrogen receptor-positive cancer, tumor cells carry many receptors on their surfaces to which estrogen can attach, fueling tumor growth. Tamoxifen works by blocking the receptors.
Experts have long debated whether women with estrogen receptor-positive cancers -- whose growth is fueled by circulating estrogen -- would get more benefit from having a chemotherapy regimen on top of tamoxifen.
Albain led a research team from multiple centers that followed nearly 1,500 breast cancer patients for up to 13 years, with a median (half longer, half less) of nearly nine years. All were past menopause and had hormone receptor-positive cancer that had spread to at least one lymph node in the armpit area.
Albain's team assigned 381 women to tamoxifen alone, 587 to chemotherapy alone and 590 to both, with some receiving tamoxifen and chemo together and some in a sequential manner.
Tamoxifen was taken daily for five years. The chemo regimen used is called CAF, for "cyclophosphamide, Adriamycin and 5-fluorouracil."
In all, after accounting for study dropouts, 1,460 women received treatment.
The combined treatments of chemo plus tamoxifen increased the women's disease-free survival by 24 percent, Albain found. When her team looked at which delivery protocol worked best -- simultaneous tamoxifen and chemotherapy or chemo followed by tamoxifen -- the sequential approach was found to be better, giving slightly better disease-free survival.
Ten-year disease-free survival estimates were 57 percent for the combination group and 48 percent for the tamoxifen-only group, the researchers found.
However, women receiving chemo were more likely to have drops in white blood cells, important for fighting infections, the team noted. And they were also more prone to blood clots, congestive heart failure and other complications.
In a second study, Albain's team analyzed whether a gene test, called Oncotype DX, could predict which women would benefit from chemotherapy. Genomic Health, which makes the test, helped fund the study, along with the U.S. National Cancer Institute.
The test, which Albain said is already widely used, is done on the tumor itself. "This puts 21 genes together and comes up with a score," she said. The score -- low, intermediate, high -- predicts the risk of recurrence over 10 years if a woman used tamoxifen alone.
When the researchers performed the test on 367 specimens, they found a low score identified those women who may not need the chemo, despite the fact that they have cancer that spread to lymph nodes.
"This is a positive study, there's no question," said Dr. Joanne Mortimer, vice chair of medical oncology for the City of Hope Cancer Center in Duarte, Calif., of the first study. "This study tells us [that] if you have positive lymph nodes [and are postmenopausal with estrogen receptor-positive cancer], you should have both chemo and tamoxifen, because the survival was better."
But, she added, "when you give everyone [who has the estrogen receptor-positive, node-positive breast cancer] chemotherapy, probably there are some who don't need it."
According to Mortimer, that's why the gene test looks promising -- it may spare some women from having to have chemo while ensuring that those who will benefit from the treatment get it.
More information
To learn more about breast cancer, visit the American Cancer Society.

Monday, December 7, 2009

New type of vaccine against allergies.

This may be the final effect of research at Uppsala University in Sweden. New result is presented by Ms. Anna Ledin in her doctoral dissertation. She vaccinated animals like dogs and rats against their own IgE antibodies, and appears that their allergic symptoms reduce.

The new type of antibody called IgE is part of the body’s defense against parasites, but today it is best known for its key role in allergic reactions. IgE is what brings about an allergic reaction. Normally it constitutes 0.02 % of all antibodies in the blood, but people with allergies can have up to ten times as much. The best way for a person with allergies to avoid reactions is to avoid the substance that triggers the allergies. But if you are allergic to pollen it is not easy to avoid all the pollen produced by blossoming birch trees, for example, which can lead to asthma, hay fever, and/or eczema.

Anna Ledin belongs to a team of scientists at Uppsala University that is developing vaccines against allergies, under the direction of Professor Lars Hellman. Her dissertation is part of this project. She presents a new form of treatment for allergies in her study. By producing and injecting an IgE vaccine that looks like IgE, she demonstrates that the body perceives the vaccine as something alien. Antibodies are then produced to fight both IgE and the vaccine, bringing down the levels of IgE in the blood and reducing the allergic symptoms. The allergy vaccine has been tested on rats and dogs, and the results indicate a clear reduction of IgE levels after vaccination. Dogs are one of the few animals that have allergic reactions like humans, but it has been unclear just how IgE levels are related to their symptoms. A new method for monitoring IgE levels in the blood of dogs was developed by the research team, and it was found that dogs have extremely high levels of IgE, regardless of whether they were healthy or had allergic eczema, autoimmune disorders, or skin parasites. This makes it problematic to diagnose allergies merely on the basis of IgE from dog blood. What’s more, IgE was measured from three sets of puppies, and, unlike mature dogs, the puppies evinced low levels of IgE.

What causes allergies then? It is certain that both environmental and genetic factors play a role. But it has not been determined exactly which genes are involved or to what extent they are involved. Therefore Anna Ledin and the research team examined how a part of one chromosome, containing many different genes, is involved in the regulation of IgE in rats. That particular chromosomal region has previously been implicated in the susceptibility of rats to developing pain in their joints in a model for arthritic rheumatism, and they found that it also affects IgE levels in rats. It remains to be studied whether this chromosomal region also impacts IgE levels in humans.

Sunday, December 6, 2009

Cryosurgery treatment for Cancer

Cryosurgery abides a novel method for treatment of cancer which has been accepted by the united states' food & drug administration (FDA) in 1998 also China's SFDA in 1999. Fuda cancer Hospital-Guangzhou has applied the method since 2000. To date, Fuda has the best amount of experience in this minimally invasive operation; usual Fuda trains doctors from around the world on the cryosurgery technique. recently, Fuda's number of cryosurgery cases has nearly topped 5,000 cases with a variety of malignant tumors (more than 34 different kinds of cancers). In this field, Fuda Cancer Hospital leads the world in experience and research.


Principle


Cryosurgery is an important ablation technique for tumors. It destroys tumors by cycles of freezing and thawing. Cryosurgery's destructive effects on tumors are due to two major mechanisms, one immediate, the other delayed. The immediate mechanism is the damaging effect of freezing and thawing the cells. The delayed mechanism is the progressive failure of microcirculation; ultimately, vascular stasis becomes operative as an important cause of tumor tissue destruction. Once the temperature falls below -40oC, ice crystals may form within the cells. Once it occurs, cell death is almost certain. During cryosurgery, progressive failure of microcirculation occurs due to a cascade of events: endothelial layer destruction causing vessel walls to become porous, interstitial edema, platelet aggregation, microthrombi, and ultimately vascular congestion and obliteration. It was theorized that during cryosurgery, the immune system of the host became sensitized to the tumor being destroyed by the cryosurgery. Any primary tumor tissue undamaged by the cryosurgery and the metastases were destroyed by the immune system after cryosurgery. This response was termed the "cryo-immunological response".


Procedure of cryosurgery


Cryosurgery is performed through intraoperative, endoscopic or percutaneous routes depending upon the location and size of tumor.

Cryoablation is performed by using argon-helium system. Two to three cycles of the freezing/thawing are performed. The freezing continues until the "ice-ball" formed at the tip if the cryoprobe is large enough to cover tumor. A 5-10 mm margin of normal tissue is included in the freezing process. For larger tumors, multiple cryoprobes were used. In some cases, it may become necessary to perform at least 2-3 sessions of the cryoablation procedure. This is possible because the procedure is minimally invasive, and often does not require cutting. The probes are simply inserted through the skin and guided by real-time ultrasound.

Advantages

  • Cryosurgery is a localized medical procedure. It can be used as the sole means of cancer treatment or it can be combined with other conventional treatment techniques such as surgical operation, chemotherapy, radiotherapy.

  • Combining cryosurgery with excision can be advantageous since freezing the tumor before excision minimizes the risk of spreading the cancerous cells during excision

  • In addition to sparing healthy tissue, cryosurgery is advantageous because it is not dose-limited can be repeated as necessary in order to destroy all cancerous tissue

  • In situations where the tumor is not removed after freezing, especially percutaneous cryosurgery, operative blood loss is small and post-surgical discomfort is minimized

  • Cryoprobes are relatively small (generally in the range of 24 mm in diameter) and therefore they may be used in minimally in-vasive surgical procedures

  • There are no major side effects which are commonly found in chemotherapy or radiotherapy

  • Cryosurgery is adaptable for treatment of tumor close to large vessel which cannot be removed by operation

  • Cryosurgery can treat small as well as large tumors, and solitary as well as multiple tumors

  • Cryosurgery per se aims at a local effect, namely, destruction in situ of neoplasms resistant to conventional treatments, but it also elicits an immunologic reaction (cryoimmunologic reaction) against cancer for eradication of residual or metastatic tumors

  • There is evidence that the recurrence rate of cancer after cryosurgery is lower than that of operation

Indication

Nearly all parenchymal cancers are prime candidates for cryoablation.

These malignancies include:

*Liver cancer
*Lung cancer(non-small cell lung cancer)
*Kidney cancer
*Ovarian cancer
*Pharyngeal cancer
*Testicular cancer
*Uterine tumors
*Vaginal cancer
*Pancreatic cancer
*Breast cancer
*Sarcoma and other benign or malignant lesions of bone
*Prostate cancer
*Skin cancer and melanoma
*Head and neck cancer
*Tumor of soft tissues

In addition, cryosurgery can be an effective treatment for the following:

* Retinoblastoma (a childhood cancer that affects the retina of the eye).
*Early-stage skin cancers (both basal cell and squamous cell carcinomas)
*Precancerous skin growths known as actinic keratosis.
*Pre-cancerous conditions of the cervix known as cervical intraepithelial neoplasia (abnormal cell changes in the cervix that can develop into cervical cancer).


For More information Visit:Fuda Cancer Hospital-Guangzhou