To the Editor.—The article by Fentiman et al on needle biopsy in outpatients with breast cancer (Archives 1980;115:652-653) describes an excellent technique that we commonly used before the time of estrogen-binding studies. It allowed preparation of the patient for upcoming mastectomy and it shortened time in the operating room, since further biopsy was unnecessary.
However, the extreme importance of accurate estrogen-binding studies has now made needle biopsy a less useful outpatient procedure, since fresh tissue removed immediately at the time of open biopsy is essential for reliable results from these studies. The time involved with the mastectomy with a complete axillary dissection will often be two hours of ischemia to the breast cancer prior to the sampling of the tissue by the pathologist for estrogen-binding studies. This delay may result in a false-negative result from estrogen-binding study due to the heat liability of the binding site.1 Thus, excisional