To freeze or not to freeze. A comparison of methods for the handling of breast biopsies with no palpable abnormality.

Recently there have been several editorials suggesting that breast biopsies with small or nonpalpable lesions should not be subjected to frozen section examination. In this study, the approach of routinely performing frozen sections on all breast biopsies was compared to the recommended approach of performing frozen sections only on cases with gross lesions < 1.0 cm. From July 1, 1992 through June 30, 1993, there were 444 breast biopsies submitted. Nearly all of these (98%) had frozen sections performed. Among these cases, there were 14 false-negative frozen section diagnoses equating to a frozen section sensitivity of 84%, and a frozen section false-negative rate of 3.3%. From July 1, 1994 through June 30, 1995, there were 601 breast biopsies submitted. Of these cases, 310 contained a gross lesion > 1.0 cm and were subjected to frozen section examination. The remaining 291 cases contained either no distinct lesion or a gross lesion < 1.0 cm. These cases were not frozen. Among the 310 cases that were frozen, there were 3 false-negative frozen section diagnoses equating to a frozen section sensitivity of 96%, and a frozen section false-negative rate of 1.0%. These findings indicate that careful gross examination combined with selective freezing of only cases containing a gross lesion > 1.0 cm improves frozen section accuracy. This study provides statistical support for previous recommendations that frozen section examination should be limited to cases with distinct gross lesions > 1.0 cm.