Herceptin (trastuzamab) in advanced breast cancer

Herceptin (trastuzamab, Genentech, San Francisco, CA, USA) prolongs survival in metastatic breast cancer patients whose tumours overexpress the HER2/neu protein. Compared with chemotherapy alone, patients receiving chemotherapy and Herceptin have a significantly longer time to progression, a higher response rate and a longer duration of response. These effects are most marked in first-line treatment of metastatic disease. The addition of Herceptin is associated with few additional side-effects, apart from cardiac toxicity in patients concurrently receiving anthracyclines. As such, it seems reasonable for Herceptin to become considered as one of the routine treatment options in metastatic breast cancer. It would therefore be appropriate for HER2 status testing to be incorporated into the assessment of all patients with metastatic disease. The use of this medication will be limited by its cost. Furthermore, data are lacking on appropriate treatments durations in responders.