Posts Tagged ‘trials’

Why a Pap Smear Might Not Catch All Cervical Cancers

Most women are familiar with the Pap smear, also known as the pap test. Most of us are also aware that the main goal of the Pap smear is to identify cancerous or abnormal cells that may turn into cancer after collecting them from the lining of the cervix. However, based on findings recently published in the International Journal of Cancer, Pap smears may not be the most reliable way to pinpoint cancer types that can often be harder to detect.

According to Kevin Ault, MD, an associate professor of obstetrics and gynecology at Emory’s School of Medicine and Winship Cancer Institute, the Pap smear is not always effective in the diagnosis of adenocarcinoma. Ault came to this conclusion after conducting a post-hoc analysis of Gardasil vaccine trials. Adenocarcinoma is a type of cervical cancer that begins significantly far up the cervical canal, an area that often is not sampled when a Pap smear is conducted.

Andenocarcinoma is the second most common type of cervical cancer, accounting for about 20 percent of all cervical cancer cases. While the overall incidence rate of cervical cancer is on the decline, Ault reports the proportion of andenocarcinoma cervical cancer is rising.

As the 8th most common type of cancer in American women, more than 12,000 new cases of invasive cervical cancer are diagnosed each year. Scientists believe that pre-invasive cervical cancer may develop over a period of months or years after the cervix is infected with the sexually transmitted HPV.

A leading expert and pioneer in the field of human papilloma virus (HPV), Ault suggests women might seek an HPV and Pap test at the same time. Why? A positive HPV test may be an indicator for early stages of adenocarcinoma cervical cancer that can’t be determined via a standard Pap test.

New Blood Test Aids in Early Cancer Detection

Winship at Emory’s Dr. Suresh Ramalingam explains the test and what it means for cancer detection and treatment.

Suresh Ramalingam, MDYou may have heard in news headlines this week about the ability to detect a single cancer cell among billions of healthy cells. This may be possible via a new blood test (under development) that may someday help detect cancer earlier.

For tumors located in organs such as the lung, prostate, colon and breast, access to tumor tissue is only possible with a biopsy. This requires an invasive procedure, which in certain situations involves surgical intervention. It has been known for sometime that tumors shed their cancer cells that can be found in the circulating blood stream. However, the tumor cells are a significant minority in number compared to normal blood cells. Identifying the tumor cells among billions of normal cells has been a major challenge. Currently, it is possible with sophisticated techniques to identify such cells and count them. The number of circulating tumor cells has been linked to survival outcomes in some studies. Now researchers are trying to not only count, but collect these tumor cells and then conduct molecular testing.

Such an advance would have tremendous implications for cancer research and treatment. First of all, it may not be necessary to obtain tumor biopsies if adequate number of cells can be identified in the peripheral blood. It will be possible then, to administer this test during the course of a patient’s treatment to learn how a tumor is changing, because they do change as treatment progresses. It would also be possible to diagnose cancer early as part of screening strategies for patients at risk for developing certain cancers.

So how does this test work and what does it do? The test uses a microchip resembling a lab slide covered in 78,000 tiny posts. Those posts are coated with antibodies that attract and bind to tumor cells like glue. A patient’s blood sample, about a teaspoon full, is forced across the chip. The cancer cells stick, and a stain makes them glow so researchers can capture them for study.

For patients, care-givers and researchers this is very exciting news. However, this technology is just entering the early stages of testing and will have to go through several studies before it can be applied in routine practice. A number of important research questions will still have to be answered regarding the utility of circulating tumor cells, even if the test proves to be successful.

It is important to emphasize that while the new technology is exciting, it is possibly years away from practical application. If you have questions on this new blood test, please leave them in the comments below.

Could Space Travel Cause Lung Cancer in Astronauts?

Researchers are launching a new cancer research initiative – literally. NASA partners with Emory & MCG

NASA has awarded a team of investigators from both the Winship Cancer Institute of Emory University and the Medical College of Georgia $7.6 million over five years to study how a component of space radiation may induce lung cancer.

The award establishes a NASA Specialized Center of Research (NSCOR), consisting of a team of scientists with complementary skills who work closely together to solve a set of research questions. Ya Wang, PhD, professor of radiation oncology at Emory University School of Medicine and Winship Cancer Institute, is director of the NSCOR at Emory.

Interplanetary space travel could expose astronauts to conditions where they are chronically subject to types of radiation not normally encountered on earth. One of these radiation types is high energy charged particles (HZE), which results in complex damage to DNA and a broader stress response by the affected cells and tissues.

There is no epidemiological data for human exposure to HZE particles, although some estimates have been made studying uranium miners and Japanese atomic bomb survivors. Animal experiments show that HZE particle exposure induces more tumors than other forms of radiation such as X-rays or gamma rays.

Because it is a leading form of cancer, lung cancer can be expected to be prominent among increased risks from radiation even though astronauts do not smoke. However, the risk for astronauts remains unclear because the dose of HZE astronauts are expected to receive is very low.

The Emory-MCG researchers will probe whether the broader stress response induced by HZE particles amplifies cancer risk. Investigators will collaborate with physicists at Brookhaven National Laboratory to gather information on HZE’s effects. Individual projects include the study of how cells repair DNA damage induced by HZE particles, how HZE particles generate oxidative stress, and how they trigger regulatory changes in DNA known as methylation.

“The information generated by this project will be critical for estimating risks and establishing countermeasures for cancers associated with long term space travel. In addition, new insights into cancer resulting from all types of radiation exposure, including those found on earth, are likely to emerge from this project,” concludes Dr. Paul Doetsch, PhD, professor of radiation oncology and biochemistry, and associate director of Emory’s NSCOR.