News Tips from The University of Texas M. D. Anderson Cancer Center
News Tips from The University of Texas M. D. Anderson Cancer Center
San Antonio Breast Cancer Symposium December 11 - 14, 2002
M. D. Anderson News Release 12/18/02
Examination of what may be the largest single institution "experience" in the country of treating male breast cancer suggests that radiation may be as beneficial to some men as it is to women with breast cancer.
By studying the outcomes of 143 patients seen at M. D. Anderson Cancer Center over a span of 56 years (1944-2000), researchers have concluded that men with larger breast tumors, with more affected lymph nodes and positive margins, should probably receive radiation therapy after a mastectomy.
The finding is important because no concrete guidelines currently exist to treat male breast cancer, because it is so rare. "Some centers, like ours, may offer radiation to male breast cancer patients, but many do not," says George H. Perkins, M.D., an assistant professor of radiation oncology who is presenting results of this work at the annual meeting of the San Antonio Breast Cancer Symposium.
"Many physicians are unsure how to manage the disease," he says. "Some treat male breast cancer patients as if they are females, and others take an individualized approach. But there is no consensus.
"Now it appears that some of the standards used for treating women are applicable benchmarks for male breast cancer," says Perkins. "This is a good initial step toward developing practice guidelines to treat male breast cancer."
At least 1,200 new cases of male breast cancer are diagnosed annually (fewer than 1 percent of all breast cancers) and, unlike female breast cancer, the overwhelming majority is a single subtype. About 85 percent of male breast cancer is invasive ductal carcinoma, and from 80-85 percent are hormone (estrogen, progesterone) receptor positive. Breast cancer usually develops directly underneath a man's nipple, and because a tumor does not have much room to expand, it often grows into the skin.
Mastectomy is often used to manage local disease, and in this study, 77 percent of men had mastectomy, and chemotherapy and/or hormonal therapy were administered to 53 percent of patients.
But oncologists are often unsure whether to offer radiation to their male breast cancer patients, so they examined characteristics of patients in which cancer recurred. They found that some of the same criteria that predict which women can benefit from radiation therapy also apply to men. Specifically, margin status, tumor size (5 centimeters), and the number of positive axillary nodes (four or more) significantly predicted for local recurrence of breast cancer in these patients, Perkins says.
Radiofrequency ablation may offer some women with small invasive breast tumors a way to treat their cancer without surgery and with little cosmetic harm, according to results of a small, multi-center clinical trial being presented at the San Antonio Breast Cancer Symposium.
The technique, which already has shown promise in treating liver cancer, utilizes a prong with probes that are inserted through the skin and into the tumor. High frequency radio waves then heat the tumor, killing it.
Researchers at M. D. Anderson Cancer Center adapted the procedure to treat breast cancer, and then conducted a pilot trial to test it. In this clinical trial, conducted at M. D. Anderson, New York Weill Cornell Medical Center, and John Wayne Cancer Institute, 30 women with early stage breast cancer who were already scheduled to have a mastectomy or lumpectomy agreed to have radiofrequency ablation of their tumor first.
When their breast tissue was removed, researchers examined whether the tumors had been successfully destroyed through ablation. In 28 of 30 cases (93 percent) the tumors were completely eradicated when the lesion had been accurately targeted by ultrasound.
"As promising as the technique is, patients need to be carefully selected," says Attiqua Mirza, M.D., who is presenting results of the study. The tumors should be small (two centimeters or smaller in size in this study), clearly identifiable by ultrasound, and not up against the skin or chest wall. Patients who have had prior chemotherapy to shrink their tumor may not receive the best result through ablation, Mirza adds; one patient included in the study who had neoadjuvant chemotherapy was found to have tumor cells located outside of the ablated area.
M. D. Anderson will start a new 20-patient trial of the technique within several months, and in this test, women with an early stage tumor will receive only radiofrequency ablation, and then will be closely monitored for several years. Researchers hope that tumor tissue destroyed by ablation will be reabsorbed into the body and that a patient's mammogram will eventually return to normal.
"Radiofrequency ablation is a nonsurgical lumpectomy that may be used to treat small invasive breast cancers in the future," says Eva Singletary, M.D., the M. D. Anderson Cancer Center surgeon who is pioneering use of the technique. "It has the potential to offer local control of cancer with an even better cosmetic result than lumpectomy."
Early results in an ongoing study show that a blood test is at least as effective as mammography in determining whether women have a breast abnormality, says a researcher at M. D. Anderson Cancer Center.
"If validated in further study, this blood test could represent a major step forward in early detection of breast cancer," says Gordon Mills, M.D., Ph.D, professor of molecular therapeutics.
Details of the study, a collaboration between investigators at M. D. Anderson, the National Institutes of Health (NIH), the federal Food and Drug Administration (FDA), and Duke University Medical Center, is being presented at the San Antonio Breast Cancer Symposium. Emanuel Petricoin, Ph.D., co-director of the FDA-NCI Clinical Proteomics Program, will present findings to date.
The blood test identifies a pattern of abnormal proteins that may indicate developing breast cancer. In this prospective trial, blood samples were collected from hundreds of women who came to M. D. Anderson, or to Duke, for evaluation of an abnormal mammogram or a breast mass for the presence of breast cancer. Some of these women were later diagnosed with cancer. Using the emerging science of proteomics, researchers examined all the blood samples to identify proteins present in the blood of women with cancer that are not found in women without the disease.
"A protein blood test could allow a greater ability to detect early breast cancer and to also potentially decrease the concerns that occur with false positive mammography," says Mills. He stresses, however, that future studies with larger numbers of women at multiple medical centers will be required prior to this being used at a screening or diagnostic approach.
"Ongoing studies will determine the optimal utility of this approach in conjunction with mammography," he says.
New follow-up data from the ATAC trial shows that the Arimidex (anastrozole) continues to outperform the current standard treatment, Tamoxifen, in preventing recurrence of breast cancer, according to researchers who presented the latest findings Wednesday (Dec. 11) at the San Antonio Breast Cancer Symposium.
"These results confirm that the benefits observed with Arimidex are likely to be maintained over the long term," says Aman Buzdar, M.D., professor of breast medical oncology at M. D. Anderson Cancer Center, and principal U.S. investigator of the trial.
With follow-up time now at 47 months, disease-free survival for women treated with Arimidex is 86.9 percent, compared to 84.5 percent for patients who used Tamoxifen, "with the absolute difference continuing to increase over time," says Buzdar.
The difference was even greater in hormone-receptor positive patients (about 75 percent of patients), says Buzdar. Furthermore, only 20 women using Arimidex have developed invasive contralateral breast cancer, compared with 35 women in the Tamoxifen arm - a statistically significant difference, he says.
Results presented at last year's San Antonio Breast Cancer Symposium showed that at three year's follow-up, disease free survival estimates were 89.4 percent for women treated with Arimidex, compared to 87.4 percent for patients who used Tamoxifen.
ATAC (Arimidex, Tamoxifen, Alone, or in Combination) is the largest breast cancer treatment trial ever conducted. It enrolled 9,366 women treated for primary breast cancer from 380 cancer centers in 21 countries to test the power of a new therapy, Arimidex, to prevent breast cancer recurrence, compared to standard hormonal therapy, Tamoxifen. A third arm of the trial examined whether a combination of both drugs is better than either drug alone, and to date, data on the combination therapy is not significantly different than results with Tamoxifen alone.
Arimidex is an aromatase inhibitor that blocks an enzyme that converts androgens, or male hormones, into estrogens in postmenopausal women. It was originally approved for use in advanced breast cancer, and based on results from ATAC, the FDA approved the drug for use in early breast cancer on Sept. 5, 2002. Tamoxifen is a selective estrogen receptor modulator (SERM) that works by competing with estrogen to bind to the estrogen receptors on tumor cells.
Patients are to follow their treatment regimens for five years.