Herceptin after CAF Treatment
Approximately 30% of women with metastatic breast cancer have a genetic alteration in the HER2 (human epidermal growth factor receptor2) gene causing overexpression of HER2 growth factor receptor protein on the tumor cell surface. Overexpression of this protein is associated with a more aggressive clinical course and worse prognosis. This is detected by immunohistochemical testing. Patients whose tumor over expresses the HER2 protein now can currently be treated with Herceptin under certain circumstances and the drug continues to undergo clinical studies for expanded indications.
Herceptin is given as a weekly 30-90 minute IV infusion.
It is currently indicated as a single agent (alone) for the treatment of patients with metastatic breast cancer when the tumor overexpresses HER2 after the patient has already been treated with one or more chemotherapy regimens including high dose chemotherapy with peripheral stem cell transplant. It is also indicated for the treatment of patients with metastatic breast cancer when the tumor overexpresses HER2 protein when the patient has not received chemotherapy for metastatic disease.
Herceptin can cause heart failure. When used alone the incidence of any heart failure is 7%, and 5% severe; when used with Paclitaxel (Taxol) there is an 11% incidence of heart failure and a 4% incidence of severe heart failure; when used with AC (anthracycline + cyclophosphamide) there was a 28% incidence of heart failure and 19% incidence of severe heart failure.
Because of the combined toxicity, Herceptin should not be used with an anthracycline (e.g. Adriamycin, epirubicin).
All patients receive a baseline cardiac evaluation.
Herceptin should be used with caution in the following conditions, as there is currently no data to assess whether or not Herceptin is safe:
Other associated conditions observed in patients who have received Herceptin are rare and may be as a result of the underlying disease rather than from the drug itself. Consult your physician for further information.
In the situation which you are referring to there really is no data at this point to show that Herceptin works in an adjuvant setting (to prevent recurrence) when the breast cancer is not metastatic. It would especially be concerning because of prior treatment with adriamycin. It is certainly a good thought and more data may be available in the future.