Recent findings that breast cancer has many ways of expressing itself are considered a reason the disease is on a decline.
The 12th annual Laura Evans Memorial Breast Cancer Symposium—sponsored by the Ketchum-based Expedition Inspiration Fund for Breast Cancer Research—made "New Therapeutic Approaches to Breast Cancer" its focus last week. Bristol-Myers Squibb underwrote the four-day event, and St. Luke's Wood River Medical Center sponsored an open forum on Thursday, March 6.
Because of these institutions, "every dollar we don't put out for this symposium is another dollar for breast cancer research," said Heidi Mickleson, chairwoman of the Expedition Inspiration board.
The invitation-only conference for renowned researchers and oncologists was chaired by Expedition Inspiration scientific advisor Dr. Marc Lippman, chairman of the Department of Medicine at the University of Miami and one of the world's leading authorities on breast cancer. A pioneer in studying the role of estrogen in the disease, he was a mentor to many of the researchers who attended the symposium.
"The symposium provides an incredible opportunity for scientists and leading clinical researchers," Lippman said. "A lot of wonderful things are not just in the future, (but are) happening now. It's not an idle boast to say that many of the people in front of you are responsible for that."
Among the presentations made during the symposium was given by Dr. Vijayakirishna (V.K.) Gadi, one of two 2007 Expedition Inspiration Young Investigator Grant recipients.
"The talk by V.K. this morning put us back on our heels," Lippman said.
Gadi postulated that pregnancy may be a protective factor against the development of breast cancer. During pregnancy, mothers create fetal cells. Whether they move or stay put is part of Gadi's research.
"A normal consequence of pregnancy is the transfer of cells known as fetal microchimerism cells across the placenta into the mother, where they may persist for the lifetime of the mother," Gadi said. "My colleagues and I have found that women who bore children are able to harbor the fetal microchimerism in their blood and in breast tissue when compared to similar healthy women. This might be an explanation of why mothers have a lower rate of breast cancer then women who don't have children.
"It's definitely out of the box. People were surprised."
The other Young Investigator Grant recipients, Dr. Lynn Henry, of the University of Michigan Comprehensive Cancer Center, spoke about her research into the musculoskeletal changes that accompany the use of aramatase.
Dr. Kent Osborne of the Baylor College of Medicine Breast Center, was one of two presenters at the open forum. His brief presentation was titled "Advances in Therapies: Translating Laboratory Studies to the Clinic."
Researchers have discovered that breast cancer is not one form of cancer, but many different "subtypes," diagnosed by the presence or absence of three "receptors" that feed breast cancer cells: estrogen receptors, progesterone receptors and human epidermal growth factor receptor 2, known as HER2. A quarter of all breast cancers are caused by the over-expression of the HER2 protein. Targeting these receptors has changed the face of research and treatment.
"For 25 years I did the same thing every day," Osborne said. "Although there was progress it was not an exciting time. But in the past decade (researchers) have taken cancer down to the molecular level. My interest has bounced.
"At one level all cancers are because of broken genes. They can divide and continue to proliferate, cause the blood vessels to grow and have the ability to spread."
He said a major factor in blocking that spread is drugs such as tamoxofin, raloxitene and aramatase inhibitors.
Approved recently by the FDA for women who already had drug treatment for cancer is Laptatinib, which in combination with another cancer drug, capectabine, "attacks the enzyme portion of HER2 and HER1," Osborne said.
"Also, we've been able to block the blood vessels in mice, which we've never been able to do. Blood vessels feed cancer cells, so let's target the blood."
Dr. George Sledge, of the University of Indiana Medical Center, developed the drug avastin (or bevacizumab) to target the blood vessels. The FDA approved avastin as a cancer drug a few weeks ago after many years in clinical trials.
"There are 30 to 40 factors that contribute to the growth of blood vessels," Osborne said. "The new drug will have an effect on those."
There are always exceptions to the rule, however. Sledge helped identify triple-negative breast cancer, which is unlike the receptor-fed breast cancers.
"For many of us, this is the first step to understanding it," Sledge said.
The human growth receptors are absent in triple-negative breast cancer, and therefore not treatable with estrogen-blocking drugs.
"Inflammatory breast cancer is a different entity too," Sledge said. "It looks red, is enlarged and warm to the touch. It is very aggressive, leading us to use neo-adjuvant (normally additional) therapy like chemotherapy first. This has been the mainstay of the treatment."
In breast cancer, that therapy is mainly used to shrink a large tumor so it's easier to remove.
Dr. Dan Hayes' presentation was "Personalization of Breast Cancer Therapy: Getting the Right Treatment to the Right Patient." The clinical director of the University of Michigan Breast Oncology Program, Hayes has worked in clinical and laboratory studies, advancing the management of breast cancer worldwide, and been at the forefront of individualized breast cancer therapy.
One of the points he and others made is that though there are many large centers around the country, patients have access to clinical trials at smaller institutions as well.
In 2006, St. Luke's Mountain States Tumor Institute in Boise was one of only 12 recipients in the country of the American Society of Clinical Oncology Clinical Trials Participation Award. As well as being Idaho's largest oncology center, it is considered one of the Northwest's most respected cancer-care centers. Its success is due in large part to the work of Medical Director Dr. Thomas Beck and Radiation Oncologist Dr. Ron Dorn, along with grants from organizations that include Expedition Inspiration.
Dorn is an original member of Expedition Inspiration's Medical Advisory Committee. He stressed that early diagnosis and additional, recently developed treatments of breast cancer are two of the major factors contributing to its decline.
Attendees were given a chance to ask questions of the physicians and researchers for more than an hour. The informational forum was well attended by health-care providers in the valley, among others.
On Wednesday, June 11, Expedition Inspiration will sponsor another public forum at St. Luke's Mountain States Tumor Institute in Boise.
For more information, visit expeditioninspirtion.org.