Scalp hypothermia can prevent alopecia caused by low doses of doxorubicin alone or in simple combinations. The technique was used in 60 patients with breast cancer (24 receiving adjuvant therapy; 36 with advanced recurrent disease) receiving chemotherapy with iv doxorubicin (40 mg/m2) and vincristine (1.4 mg/m2) on Day 1 together with oral cyclophosphamide (200 mg/m2) on Days 2-5. The patients' desire to continue scalp hypothermia, reflecting their perception of benefit, and an objective assessment of hair retention were the study end points. The mean number of cycles of chemotherapy given (6.1 in patients receiving adjuvant therapy; 3.8 in those with advanced disease) exceeded the number of cycles with hypothermia (2.1 in patients receiving adjuvant therapy; 1.6 in those with advanced disease); no patients retained enough hair to encourage them to continue scalp hypothermia throughout chemotherapy. All patients were rated as having poor hair retention. Scalp hypothermia is ineffective when used with combinations of drugs, each causing alopecia, or with high doses of doxorubicin.