Intraoperative diagnosis of breast lesions. Comparison of cytologic with frozen section technics.

A retrospective double-blind examination of the cytologic smears and frozen section tissue slides from 140 lesions of the breast was performed in order to assess the diagnostic accuracy of each method. The cases with diagnostic errors were reevaluated to define the pitfalls encountered in the intraoperative diagnosis of breast lesions by both methods. Results with the cytologic technics are more variable than with frozen sections, but when read by experienced observers the smears are as accurate as frozen sections and have the additional advantages of rapidity, sparing of tissue for other studies, better correlation with fine-needle aspiration cytologic results, and more complete sampling of large or multiple specimens. The authors recommend that intraoperative cytologic examination be employed routinely in breast diagnosis, initially always in conjunction with frozen section examination but eventually in many cases as an alternative technic.