Breast Cancer

I was quite disappointed with Dr. Graham A. Colditz’s review of the literature concerning the use of estrogen replacement therapy in patients with breast cancer, which appeared in the November 1997 issue of ONCOLOGY (pp 1491-1497).

Since physicians have stressed complete rehabilitation after breast cancer treatment, including breast reconstruction and psychosocial aspects, it follows that young women who have undergone such treatment may wish to resume their life roles, which often include motherhood. Consequently, the issue of pregnancy after breast cancer treatment has assumed paramount importance. This pertinent, accurate review of such a complex issue can be so brief because there are so few data on the subject. Given the diversity of the issues presented in the review, it is helpful to consider them individually.

Breast cancer, the most common malignancy in women, frequently develops during the premenopausal years. The great majority of these breast cancers can be successfully treated, and the decision to have children remains a real and important consideration. The relationship between breast cancer and a subsequent pregnancy is complex, and decisions regarding one may ultimately affect the course or outcome of the other.

Women face numerous issues if they either contemplate childbearing or become pregnant after the diagnosis of breast cancer. Based on a search of the English medical literature from 1966 to 1997, we make the following

FORT LAUDERDALE, Fla--The much-anticipated, prospective, comprehensive outcomes data base of the National Comprehensive Cancer Network (NCCN), a consortium of 16 US cancer centers, is now up and running, and includes data on almost 400 patients with newly diagnosed breast cancer collected at five NCCN sites over 3 months.

Alterations in a gene discovered last year by UT Southwestern Medical Center in Dallas scientists have been linked to breast, ovarian, and uterine cancers, the researchers reported in the February issue of Human Molecular Genetics.

WASHINGTON--Researchers terminated the treatment portion of the Breast Cancer Prevention Trial (BCPT) in late March, 14 months earlier than expected, after the study’s independent monitoring committee determined that patients receiving tamoxifen (Nolvadex) had a 45% reduction in breast cancer incidence, compared to the placebo arm.

The Oncology Nursing Society has responded to the increase of short-stay (“drive-through”) mastectomy and other forms of breast surgery for cancer.

FORT LAUDERDALE, Fla--The National Comprehensive Cancer Network (NCCN) continues to fine tune its breast cancer guideline, introduced 2 years ago. Robert Carlson, MD, of Stanford University, and chair of the Breast Cancer Guideline Committee, reviewed the proposed revisions at the NCCN’s third conference. The Network is a coalition of 16 US cancer centers.

NEW YORK--After treatment, many breast cancer patients have fears and misconceptions that hamper their sexual activity, and their partners may have them, too, Marisa Weiss, MD, said at a Cancer Care teleconference. Women may assume their partner finds them unattractive, while their partner may be afraid of causing injury.

FORT LAUDERDALE, Fla--The National Comprehensive Cancer Network (NCCN), a consortium of 16 leading US cancer centers, has ventured into the contentious area of breast cancer screening, and in its first draft, the breast cancer screening committee has recommended annual mammography screening for all women age 40 and over.

VILLEJUIF, France--The addition of a retinoid to adjuvant chemotherapy provided a hint of a survival advantage over chemotherapy alone for breast cancer patients, but the difference did not achieve statistical significance, according to 13-year follow-up data from a randomized clinical trial.

To determine the most effective strategies for the treatment of postmenopausal hormone dependent breast cancer, we recently developed a model system in nude mice. In this model, estrogen receptor-positive human breast cancer cells (MCF-7) stably transfected with the aromatase gene are inoculated into ovariectomized, immunosuppressed (nude) mice.

Toremifene (Fareston) received FDA approval in 1997 for the first-line treatment of postmenopausal women with estrogen receptor (ER)-positive or -unknown metastatic breast cancer. Phase II and III trials have demonstrated that first-line therapy with toremifene, 60 mg/d, is as effective and as well tolerated as tamoxifen (Nolvadex), 20 or 40 mg/d, in such patients.

Various ongoing double-blind clinical trials are evaluating the use of tamoxifen (Nolvadex) as chemoprevention for breast cancer. A total of over 24,000 healthy women have been randomized to these trials, and it should be possible, by the year 2000, to detect any preventive effect of tamoxifen in healthy women. Furthermore, with the large numbers of women involved, it should be possible to evaluate prevention in subgroups of participants according to risk of the disease, particularly those women carrying high-risk genes, such as BRCA1 and BRCA2.

Tamoxifen is by far the most clinically tested antiestrogenic drug currently used as adjuvant therapy for breast cancer and it continues to provide considerable benefit in this setting. The balance from clinical trials indicates a strong association between the use of tamoxifen and an increase in uterine tumors (three to sixfold). In rats, tamoxifen is a mutagenic, genotoxic hepatocarcinogen.

When results from the phase II trials of toremifene (Fareston) and tamoxifen (Nolvadex) in metastatic breast cancer were published, the Finnish Breast Cancer Group began to plan the first trial of toremifene in an adjuvant setting. This multicenter, randomized trial is comparing toremifene (40 mg/d) to tamoxifen (20 mg/d) in postmenopausal lymph node-positive breast cancer patients.

Letrozole (Femara) is a nonsteroidal aromatase inhibitor that is approximately 10,000 times as potent as aminoglutethimide in vivo. Two pivotal multinational phase III trials have compared letrozole (0.5 and 2.5 mg/d) against megestrol acetate and aminoglutethimide, respectively, in patients with locally advanced or metastatic breast cancer.

The new generation of potent steroidal and nonsteroidal inhibitors of the enzyme aromatase act by decreasing estrogen production throughout the body in postmenopausal women. The most potent of these agents may also inhibit estrogen synthesis within metastatic breast cancer tissue.

NEWPORT BEACH, Calif--Despite recommendations to the contrary, cancer specialists continue to order radiologic tests that rarely provide useful staging information about patients with early-stage breast cancer, results of a California study show.

Toremifene (Fareston), the first new antiestrogen agent for treating advanced breast cancer available in the United States in more than 19 years, is as effective as tamoxifen (Nolvadex) in clinical trials and potentially safer, Richard Gams, md, professor of internal medicine and director of hematology/oncology, Ohio State University, said at a teleconference sponsored by Schering-Plough to introduce the recently approved agent.

TAMPA, Fla--Sentinel lymph node evaluation can eliminate the need for total axillary dissection in 75% of breast cancer patients, Alan Shons, MD, said at the 20th Annual San Antonio Breast Cancer Symposium.

The aromatase inhibitor letrozole (Femara), at a dosage of 2.5 mg once daily, is an effective therapy for advanced breast cancer in postmenopausal women whose disease progresses following antiestrogen therapy, according to data published in the February 1998 Journal of Clinical Oncology. The study was conducted by the Letrozole International Trial Group and was sponsored by Novartis Pharmaceuticals Corporation.

ORLANDO--Breast-conserving therapy appears to be a viable treatment option for breast cancer patients with a family history of breast cancer, Elizabeth Chabner, MD, said at the annual meeting of the American Society for Therapeutic Radiation and Oncology (ASTRO).

Cancer researchers and clinicians need to adopt a new attitude toward race classifications as interracial parentage in the United States continues to increase. “I want to uncouple race and genetics,” stated Edison Liu, MD, at the 1997 Biennial Symposium on Minorities, the Medically Underserved, and Cancer held in Washington, DC.