March 1, 2011

Herceptin Benefits for Women with Breast Cancer

(Ivanhoe Newswire) -- For women with aggressive early-stage breast cancer (HER2-positive disease), trastuzumab (Herceptin) given for one year after chemotherapy proved to put the women at significantly less risk of the cancer returning. The effect is long lasting, according to this study.

Around 20% of women with breast cancer have HER2-positive cancer and are at high risk of cancer recurrence and of dying from the disease. Trastuzumab is a monoclonal antibody developed to block the cancer-causing activity of the HER2 protein and has been shown to prolong survival in patients with advanced breast cancer.

The one-year follow-up showed that 1 year of adjuvant trastuzumab significantly reduced the risk of disease recurrence by 46%. On the basis of these results, a protocol amendment allowed patients in the observation group who were disease free and had normal heart function to receive trastuzumab. A second analysis published in 2007, at the two year follow-up, confirmed the significant improvement in disease-free survival (DFS) after 1 year of trastuzumab and also showed a significant improvement in overall survival (OS).

After 4 years, trastuzumab was associated with significantly better DFS compared with chemotherapy alone (78.6% vs 72.2%), reducing the likelihood of cancer coming back by 24%. However, there was no significant difference in risk of death between the trastuzumab and observation groups (89.3% vs 87.7%), which was most likely the result of the cross-over impact.

Trastuzumab was generally well tolerated, although more serious side-effects were recorded in the trastuzumab group than in the observation group. In addition, the rate of congestive heart failure remained low during the longer follow-up.

"These findings confirm that adjuvant trastuzumab [Herceptin] given sequentially to chemotherapy is associated with significant and persisting benefits, and remains an appropriate treatment modality in patients with HER-2 positive early breast cancer. The optimal duration of trastuzumab therapy is the subject of ongoing studies," the authors were quoted as saying.

SOURCE: Lancet Oncology, published online February 24, 2011