The CancerWeb Report, What's New In Cancer: August, 1996
Breast Cancer

• Should tamoxifen treatment to prevent breast cancer recurrence last more than 5 years? - Tamoxifen is being widely studied to determine whether its use can reduce the chance of recurrence following treatment of breast cancer. The results that are accumulating suggest that no more than 5 years of tamoxifen should be given. A new Scottish study, published in the July, 1996 issue of the British Journal of Cancer, is in complete agreement with this. Analysis of data on 342 patients followed for an average of 6 years indicated that there was no additional benefit from giving tamoxifen beyond 5 years, and in addition, the risk of uterine cancer increased with longer treatment. (Stewart, Br J Cancer 74:297, 1996)

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• When is it best to give high-dose chemotherapy with bone marrow rescue? - Information presented at the 18th San Antonio Breast Cancer Symposium, 1966 provided a surprising answer. Patients with metastatic breast cancer who responded completely to induction chemotherapy with adriamycin, methotrexate and 5-fluorouracil, either received immediate high-dose chemotherapy with cyclophosphamide, cisplatin and carmustine, with bone marrow support (consolidation therapy), or were just observed. Disease-free survival in those only being observed was about 4 months compared to 22 months in those receiving consolidation therapy. It was especially interesting that when the patients from the observation-only group received consolidation treatment when they relapsed, their overall survival time was over 38 months, longer than for those who had received immediate consolidation treatment. (Peters, Breast Cancer Res Treat 37:35, 1996)

  Editor's Comment: - This surprising result suggests that there is no disadvantage in delaying intensive high-dose chemotherapy and bone marrow support until a relapse actually occurs. The study involved 442 patients, 96% of whom responded to initial chemotherapy and were divided into the two groups, so the numbers and survival times were significant from a statistical point of view. It would be nice to have confirmation of this to provide reassurance to patients and their doctors.

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• Tomudex, a new drug in the treatment of breast cancer. - An early international clinical trial, sponsored by the Institute of Cancer Research in the UK and Zeneca Pharmaceuticals, indicated that the new drug, Tomudex, is at least as effective in treating advanced breast cancer as a number of other commonly used chemotherapy drugs. As reported in the August, 1996 issue of the British Journal of Cancer complete and partial responses occurred in 26% of patients, and 44% of those with liver metastases. Tomudex may represent a new component for inclusion in the combined chemotherapy treatment schedules for breast cancer. (Smith, Br J Cancer 74:479, 1996)

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• Aspirin, no preventive against breast cancer! - A large, long-term study carried out by a group of researchers at Harvard University looked at the potential effect of regular use of two or more aspirin tablets weekly between 1980 and 1988 on the incidence of breast cancer through 1992. There were 2,303 confirmed cases from among 89,528 registered nurses in the study, which appeared in the July 17, 1996 issue of the Journal of the National Cancer Institute. The results showed that regular use of aspirin neither reduced nor increased the risk of breast cancer, even in the group of heavy users (14 or more tablets per week). (Egan, JNCI 88, 1996)

  Editor's Comment: - There is convincing evidence that aspirin and some other non-steroidal anti-inflammatory drugs (NSAIDs) reduce cancer incidence in the large bowel. A few studies have indicated that the same protective effect might apply also to breast cancer. Other studies have not shown such an effect, or the data supporting a protective role have been less convincing than for colon cancer because of problems in the way the studies were carried out. This large study of nurses is the most convincing evidence to date for lack of an effect, but clearly the final answer is not yet in.