35 patients were studied to determine the effectiveness of scalp hypothermia in the prevention of alopecia caused by adjuvant chemotherapy for breast cancer. Scalp hypothermia was induced by the newly developed Theracool cooling machine. The chemotherapeutic regimen consisted of one perioperative course of doxorubicin 50 mg/m2, cyclophosphamide 600 mg/m2 and 5-fluorouracil 600 mg/m2 (EORTC protocol 10854). Only 4 (11%) patients showed acceptable hair preservation (no or minor alopecia). 12 patients (34%) had moderate alopecia, all requiring a wig. 19 patients (54%) had complete alopecia. No scalp metastases were observed after scalp cooling. These results and a review of the literature suggest that scalp hypothermia to prevent alopecia may only be effective in a cytotoxic regimen containing an anthracycline as the sole alopecia-inducing agent. With current adjuvant chemotherapy for breast cancer, in which a combination of cyclophosphamide and an anthracycline is often used, there is no place for scalp hypothermia.