New Approaches for Adjuvant Therapy

	Tweet

Historically, adjuvant chemotherapy has been tested in combination regimens, in which one multiagent regimen is cycled over time to allow recovery of normal tissues (in particular, hematologic recovery). The doses of each agent in the combination must be reduced from full single-agent doses to permit for acceptable toxicity. Recently, the use of full-dose single agents administered in a sequential fashion (e.g., doxorubicin for 4 cycles, followed by paclitaxel for 4 cycles, followed by cyclophosphamide for 4 cycles) to increase the dose intensity of the regimen has been explored.

In addition, the concept of dose density has also been investigated, in which similar doses of drugs are administered over shorter intervals of time (every 2 weeks as compared with every 3 weeks), with the use of colony-stimulating factors (G-CSF) to promote faster hematologic recovery between cycles. The concepts of dose intensity and dose density are being investigated in ongoing cooperative group trials, and answers to these questions should be available in the next few years.

A new approach to therapy that has been investigated in patients with metastatic disease is the use of trastuzumab (Herceptin®), a monoclonal antibody that is directed against the HER-2/neu receptor. When added to chemotherapy, trastuzumab has been shown to increase the efficacy of single-agent paclitaxel and doxorubicin in the metastatic setting in women with tumors that overexpress the HER-2/neu gene. 

Presently, trials are underway to evaluate trastuzumab in the adjuvant setting, both in combination with chemotherapy and as single-agent maintenance therapy. Since this drug was found to increase doxorubicin-associated cardiotoxicity, careful cardiac monitoring will be an important component of these trials.

The EBCTCG will continue to perform overview analyses every 5 years, with the next planned analysis in the year 2000. At that time, there will be additional follow-up of trials addressing the duration of tamoxifen (10 vs. 5 years) and the addition of doxorubicin and paclitaxel to adjuvant regimens.

Although adjuvant therapy has contributed to the declining mortality of our patients, new strategies for the treatment and prevention of breast cancer are needed if mortality is to continue to be significantly reduced in the future.

Maura N. Dickler
American Cancer Society Guidelines for the Early Detection of Breast Cancer: Update 2003. CA Cancer J Clin 2003

References

1. Early Breast Cancer Trialists' Collaborative Group. Tamoxifen for early breast cancer: An overview of the randomized trials. Lancet 1998; 351:1451-1467.
2. Early Breast Cancer Trialists' Collaborative Group. Polychemotherapy for early breast cancer: An overview of the randomized trials. Lancet 1998; 352:930-942.
3. Early Breast Cancer Trialists' Collaborative Group. Ovarian ablation in early breast cancer: Overview of the randomized trials. Lancet 1996; 348:1189-1196.
4. Fisher B, Costantino JP, Wickerham DL et al. Tamoxifen for the prevention of breast cancer: Report of the National Surgical Adjuvant Breast and Bowel Project P-1 study. J Natl Cancer Inst, 1998; 90:1371-1388.
5. Gianni Bonadonna, Guest Editor. Breast Cancer. Seminars in Oncology 1996; 23:413-532.

RELATED STORIES:
Dilemma of “Earlier” detection   Fat Necrosis   Breast Cancer Screening   HRT After Diagnosis and Treatment of Breast Cancer   Nipple Discharge   Radiation treatment for breast cancer   Using Breast Density to Predict Breast Cancer Risk   Cysts   Conclusion - Biology of High Risk Benign Breast Lesions   Sensitivity, Specificity, and Positive Predictive Value   Fat necrosis of the breast   Breast Cancer after Childhood Cancer   Breast Cancer & Risks of Pregnancy   Chemotherapy in the Adjuvant Setting   Urinary Incontinence in patients with breast cancer   Developing Technologies for the Early Detection of Breast Cancer   Surgical Approach   Prophylactic Oophorectomy and breast cancer   Disease Burden - Screening for Breast Cancer   Early Detection of Breast Cancer   Nodularity   Other Screening Tests

Comments

[ + Post Your Own ]

Now you're in the public comment zone. What follows is not Armenian Medical Network's stuff; it comes from other people and we don't vouch for it. A reminder: By using this Web site you agree to accept our Terms of Service. Click here to read the Rules of Engagement.

There are no comments for this entry yet. [ + Comment here + ]