|Cancer Cells in Blood
Preliminary studies using a new technology that dramatically enhances
scientists ability to detect cancer cells in blood (CCIB) have
been conducted by UVM/Fletcher Allen oncology surgeon David Krag.
Cancer cells shed into the bloodstream; consequently, the presence
of postoperative CCIB after the expected clearing of cells suggests
the cancer has metastasized, or spread to other sites in the body.
Breast cancer patients who have CCIB 30 days after removal of
the primary tumor will be monitored for at least five years to
help determine if CCIB is a significant predictor of recurrence
and disease-free survival.
Cyclin-D: Recent evidence suggests that cyclin-D, a protein produced
at inordinately high levels in many breast cancer patients, may
interact with estrogen receptors in a manner that allows tumor
cells to grow even in the absence of estrogen. Pathologist James
Koh hopes to determine why cyclin-D is so important to tumor growth
and whether the proliferation of cyclin-D may render the cancer-preventive
drug tamoxifen less effective.
Kinase-C: Sue Jaken, associate director for basic research at
the Vermont Cancer Center (VCC), is studying the biochemical pathways
involved in tumor growth and progression and the potential of
these pathways as future targets for chemotherapeutic agents.
At the VCCs 15th Regional Research Symposium in March, she reported
her findings that too much of a cell protein known as kinase-C
(PKC) encourages the spread of breast cancer cells, while reducing
PKC levels seems to halt the spread of the disease.
Psychologists Bruce Compas and Linda Luecken are studying how
women with breast cancer cope with the stress of their diagnosis
and treatment and how psycho-social factors impact their immune
systems. Women newly diagnosed with the disease are participating
in two types of support groups one focused on expressing emotions
in a supportive environment, and a second emphasizing stress-management
and coping skills. Measures of psychological adjustment and quality
of life, along with blood levels of cortisol, a hormonal indicator
of stress, T-cells, which regulate immune response, and natural
killer cells thought to fight cancer, provide the physiological
Seeking genes that may cause breast cancer and examining the family
histories of women with a high probability of inheriting the disease
are among genetic studies led by UVM/Fletcher Allen oncologist
Marie Wood, whose research encompasses high-risk breast cancer
screening, prevention, and the psycho-social impact of genetic
testing on patients and their families. Pending is another project
that would educate primary care physicians about cancer genetics.
Dr. David Krag and his colleagues led a multi-institutional study
that accurately measured the spread of cancer to lymph nodes in
97% of patients using a procedure that makes it possible to identify
and trace the sentinel lymph nodes, in the chest and armpit, where
metastatic cells from a tumor would spread first. Krags pioneering
procedure was launched this summer as a long-term national trial,
in which breast cancer patients will undergo sentinel node therapy
or axillary lymphadenectomy (in which the lymph nodes around the
breast and armpit are removed to assess the spread of cancer)
to compare the effectiveness of the two methods as measured in
overall and disease-free survival.
A national five-year study of tamoxifen and raloxifene (STAR)
announced in May, and coordinated throughout Vermont by UVM/Fletcher
Allen oncology surgeon Seth Harlow, is enlisting healthy local
women at increased risk of breast cancer to compare the effects
of two cancer-fighting drugs. Tamoxifen has been shown to reduce
the chance of breast cancer in at-risk women by 50 percent, but
the drug also increases risks of developing uterine cancer and
blood clots in the lungs. Raloxifene is an osteoporosis-prevention
drug believed to have the potential to prevent breast cancer with
fewer side effects than tamoxifen.
Dr. David Krag is leading studies to develop a guidance molecule
that would target chemotherapeutic drugs directly to breast cancer
cells without destroying normal cells. The first step was to construct
libraries of 20 million different, small, natural molecules called
peptides. Within these libraries researchers have and will continue
to search for peptides that bind specifically to breast tumor
cells. The first clinical trials of this tumor-targeted therapy
on breast cancer patients will be launched at UVM in the near
In the most comprehensive study of its kind, oncologist Seth Harlow
is using ultrasound as a guide to excise breast cancers that are
not palpable. To date, the procedure has yielded positive results
in 62 women who have undergone ultrasound concurrently with surgery.
Results of the study will be published in September.
Dr. Harlow also is using ultrasound, which makes most invasive
tumors visible, in a second study: Here the procedure functions
as a tool to reduce further surgeries in patients with cancer
found in the sentinel nodes.
The Vermont Mammography Registry, a component of the Vermont Breast Cancer Surveillance System, collects data from all breast imaging and breast pathology facilities in Vermont. As of April of this year, more than 112,000 Vermont women, 301,000 mammograms, and 2,465 breast cancers were included in the registrys database. Data are used to provide quality assurance feedback to radiologists and facilities and for a variety of research studies. The Vermont Breast Cancer Surveillance System, an NCI funded cooperative agreement led by Berta Geller in the Office of Health Promotion Research, is one of nine sites in the National Cancer Institutes Breast Cancer Surveillance Consortium.
Breast cancer and related Web sites