Tumor Stem Cell Breakthrough

Tumor Stem Cell Breakthrough

A profound discovery has just been announced regarding breast cancer tumor cells which will impact the techniques that researchers have traditionally used to target cancer cells. A study conducted by doctors Michael F. Clarke and Max S. Wicha at the University of Michigan in Ann Arbor refutes the initial notion that cancer grows exponentially as a collection of cells. Instead, Clarke and Wicha discovered that only a small population of cells within a tumor were able to create tumors by developing into different types of cells present in a tumor. According to Dr. Clarke, this small population of cells resemble the adult stem cell because they are able to “make copies of themselves – a process called self-renewal – and produce all the other kinds of cells in the original tumor. Similar cells have been identified in leukemia in humans, but these are the first to be found in solid tumors.”

BABCN found out that in this study Clarke and Wicha examined cells from nine human breast tumors. In order to distinguish the cells, the researchers looked for proteins attached to the outside of specific cells. Using these proteins as “markers,” the researchers grouped the tumor cells into two different classes which they inserted into the mammary glands of mice. Tumors developed when they inserted 200 of one class of cells. No tumors developed when they injected 10,000 of the second class of cells. When a tumor developed in a mouse, the researchers isolated the cells into the same two categories and injected these cells into another mouse. Dr. Clarke noted that upon repeating this process four times, “tumor cells with this particular surface marker pattern [cells in class one] produced a new tumor in the next generation of mouse every time.”

Robert A. Wienberg of the Whitehead Institute for Biomedical Research, an early pioneer in the study of cancer-causing genes, believes that this study “creates a whole new conceptual paradigm on how tumors form” and that “it has profound implications for how we think tumors evolve and how we treat tumors.” Although conventional therapies effectively destroy the majority of cells within a tumor, they may miss some cancer cells that could be of the tumor stem cell class, thus facilitating cancerous tumors to recur. Dr. Wicha points out that “for the first time we can define what we believe are the important cells – the cells which determine whether the cancer will come back or be cured. Before this, we didn’t even know there were such cells.”

The direction of developing new cancer treatments may now be focused upon these stem cells. Unfortunately, because stem cells are less mature they are able to resist chemotherapy drugs more easily than mature cells. “Stem cells are more difficult to kill. Because they are so important throughout a person’s lifetime, they have developed mechanisms that protect themselves,” Dr. Wicha explains.

Although the researchers agreed that their work is some steps away from clinical use, they hope to find pathways to target the cancer causing stem cells this year. “Now that we can actually identify them, we can start developing treatments to specifically target and hopefully eliminate them,” expressed Dr. Wicha. However, Dr. Clarke indicated that finding the chemicals to attack the cells and developing ways to use them could take five to ten years.…

Brachytherapy and MammoSite Treatment

Brachytherapy and MammoSite Treatment

Brachytherapy, a form of radiation treatment, has been offered as an alternative to and in conjunction with traditional radiation treatment for some time. Used as therapy for many different types of cancer including prostate cancer, brachytherapy has generally been used in cases of breast cancer where the patient has decided to undergo a lumpectomy rather than a mastectomy. Because a lumpectomy only removes the cancerous tumor within the breast and leaves the rest of the breast intact, there is a chance that cancer may recur in the cells near the margins of tumor excision. To combat these cancerous cells, radiation therapy is often used to destroy any cancer cells that may still exist in the breast.

Traditional radiation therapy consists of daily or weekly radiation treatment to the outside of the breast area for a period of up to 6 months. In contrast to traditional radiation treatment, brachytherapy employs the use of radiation from the inside of the body through a set of 10 – 15 catheters, rather than radiation applied to the outside of the affected breast. The catheters remain in the body for one week while a series of 5 to 10 radiation treatments are conducted. During therapy, a radioactive seed (Iridium-192) is placed within the catheter producing a radioactive beam for no longer than 15 minutes. Though the process itself is painless, the insertion of the catheters is highly invasive. MammoSite, approved by the FDA in May 2002 is a less invasive form of brachytherapy. Instead of employing multiple catheters, MammoSite requires the insertion under local anesthetic of one catheter and a balloon into the cavity where the lumpectomy was performed. A radioactive pellet is attached to a wire which is inserted into the catheter and the balloon. A specific amount of radiation is delivered to the surrounding breast tissue twice a day for a period of five days.

Due to the short treatment length of brachytherapy over traditional radiation therapy, chemotherapy can also be utilized sooner if radiation therapy is conducted first. Dr. Robert Kuske of the Univ. of Wisconsin at Madison notes that “There is an 8 week delay in chemotherapy if external beam [traditional] radiation is given first and there is typically a 3.5 month delay if external beam radiation is given after chemotherapy.” Because research has proven that radiation therapy completed without delay is most effective, brachytherapy offers some promising results.

Furthermore, because the treatment is conducted from inside the body and is focused on the area of lumpectomy, areas such as other parts of the breast, lungs and heart are not treated. This also results in a smaller surface skin burn and scar possibility that is generally associated with traditional radiation therapy.

While brachytherapy has not been found to be more effective than traditional radiation therapy, proponents of breast conservation treatments in breast cancer regard brachytherapy as an important option for women contemplating a lumpectomy over a mastectomy. According to Dr. Kuske, “50 percent of eligible women with early stage breast cancer still opt for a mastectomy” based on the fact that time constraints due to family and work render traditional radiation therapy logistically impossible. “MammoSite could make it easier for more women to consider the choice of lumpectomy and provides physicians with an important new tool for the practice of breast conservation therapy.”

MammoSite and brachytherapy are recommended for tumors smaller than 2 cm and the shape and size of the cavity created by the lumpectomy must also be taken into consideration. Further clinical trials must be completed to determine the long-term efficacy of the treatments.

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Three-Step Breast Health Plan

Three-Step Breast Health Plan

Every woman is at risk for breast cancer and this risk increases with age. Most women diagnosed with breast cancer do not fit the “breast cancer risk profile.” Although a woman’s risk for breast cancer is greater if her grandmother, mother or sister has had breast cancer, 80% of all women diagnosed with breast cancer have no family history of disease. Early detection is still your best protection. Take charge of your health with this simple three-step plan.

1. Monthly Breast Self-Examination
Breast development stabilizes around age 20, so this is a good time for women to become familiar with the “geography” of their breasts through a breast self-exam (BSE). This familiarity will help you notice breast changes, including an unusual lump, skin texture changes, and uneven or asymmetrical changes of the breast or nipple.

Monthly breast self exam (BSE) is recommended about a week after your period begins for pre-menopausal women. After menopause, select a day within the month that is convenient or memorable. If you notice a change in your breast, including a lump or thickening, any unusual nipple discharge, redness, swelling, or dimpling of the breast you should schedule an appointment with your doctor. These changes do not necessarily indicate that you have cancer, so don’t panic, but do check with your doctor.

2. Screening Mammography
A mammogram is a screening tool, a special type of X-ray of the breast that can show a tumor or a worrisome area of calcifications before other symptoms occur. Women in their forties should discuss their health history with their doctor to determine annual or bi-annual screenings. All women 50 years and older should have an annual mammogram. To find a federally accredited mammography center, call the American College of Radiology (ACR) at 800-227-6440 or visit the Food and Drug Administration (FDA).

3. Clinical Breast Exam
Your yearly medical check up should include a careful breast exam. A good clinical breast exam (CBE) consists of a medical history, a visual examination of the breasts, an examination of the lymph nodes at the base of the neck and in the armpits, and a thorough palpation of the breast tissue. Family history is also important for assessing a woman’s risk factors.

During the visual exam, the patient should be upright to more easily examine the breast tissue just above the collarbone and to check for dimpling of the skin, retraction of the nipple, or changes in size or texture of the breast and skin. Flexing chest muscles by placing the hands on hips makes a woman’s underlying ligaments more prominent and accentuates any irregularities. While still upright, some doctors probe the underarm lymph nodes and the lymph nodes above the collarbone. Finally, the doctor palpates the breast tissue while the woman is lying down with her arms above or behind her head. If a woman has large breasts, the doctor may have the woman lie on her side in order to more fully examine all breast tissue.

BABCN is here to provide you with the best information possible.  If you have any questions, send us an email.…

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