To the Editor: In May, the National Cancer Institute took the unprecedented step of providing practicing oncologists with unpublished data on adjuvant systemic treatment of patients with breast cancer.1 The purpose of the communication was apparently to urge clinicians to give adjuvant treatment to all patients who have no metastatic involvement of the axillary nodes. This is a major departure from existing practice in the dissemination of the results of clinical trials, and it raises several problems.In the haste of releasing the information, errors were made in the communique, requiring the mailing of a second "clinical alert"2 to the . . .