Goserelin

SAN ANTONIO -- Goserelin is an attractive alternative to adjunctive chemotherapy in many women with early breast cancer, Dr. Walter Jonat said at a breast cancer symposium sponsored by the San Antonio Cancer Institute.

Monotherapy with the GnRH agonist analogue goserelin (Zoladex) was as effective as triple-drug chemotherapy but with substantially fewer side effects and better quality of life in peri- or premenopausal patients with estrogen receptor--positive, lymph node--positive breast cancer in the Zoladex Early Breast Cancer Research Association (ZEBRA) trial, reported Dr. Jonat of the University of Kiel, Germany.

ZEBRA was a 102-center controlled trial in which 1,614 pre- or perimenopausal patients underwent breast cancer surgery and were then randomized to 2 years of goserelin monotherapy or 6 months of adjunctive chemotherapy with cyclophosphamide, methotrexate, and 5-fluorouracil.

After 3 years of follow-up in the AstraZeneca-sponsored trial, disease-free survival in the 1,189 patients with estrogen receptor-positive tumors was identical regardless of whether they received goserelin or chemotherapy. But adverse effects were much fewer with goserelin. Given by monthly injection, goserelin was more convenient than combination chemotherapy requiring frequent lengthy visits.

During the 6 months that the patients were on chemotherapy,, their overall quality-of-life scores, activity level, physical distress score, and effort to cope with illness were significantly worse than in the goserelin group. The side effects of chemotherapy consisted chiefly of nausea, vomiting, and hair loss, while goserelin-treated patients complained of hot flashes and vaginal dryness during the 2 yearsthat they were on the medication.

At the 6-month mark, all patients in the goserelin-treated arm were amenorrheic, as expected since the therapeutic goal was to induce a reversible medical oophorectomy At this point, two-thirds of patients in the chemotherapy arm were amenorrheic, but the amenorrhea apparently was irreversible. After 3 years--a full year after completion of goserelin therapy and 2 1/2 years after conclusion of chemotherapy--only one-third of the goserelin group remained amenorrheic, while 80% of the chemotherapy-treated patients had amenorrhea and vasomotor symptoms.

The ZEBRA data suggest that goserelin might be a better option for long-term preservation of bone mineral density. During their 2 years of goserelin therapy, patients had greater loss of bone mineral density than did women on chemotherapy; however, posttreatment partial recovery of bone mineral density was observed in the goserelin group, while bone mineral density loss worsened in the months and years following triple-drug chemotherapy. (See chart.)

COPYRIGHT 2001 International Medical News Group
COPYRIGHT 2001 Gale Group