[Comparative immunohistological studies of the localization of the carcinoembryonic antigen in benign and malignant breast tissue].

By means of immunoperoxidase techniques carcinoembryonic antigen (CEA) has been localized first in carcinomas of the gastrointestinal tract and then also in other malignant tissues, such as carcinomas of the female genital tract and the breast. There is still an obvious need for intensive studies of the possible effects which the initial tissue processing, i. e. different fixation procedures may have on the localization results of CEA. By using the two step HRP-labelled antibody technique, we studied comparatively the effect of the most employed fixations on tissues from patients with mammary carcinomas and benign breast lesions: 1. Formalin-fixed and paraplast-embedded tissues 2. Cryostat sections of tissues fixed in ethanol and acetone 3. Parablast embedded tissues fixed by the freeze substitution method. The latter sections were tested whether there was any difference in the CEA localization when using the immunofluorescence or immunoperoxidase staining techniques. We concluded from our studies that routinely fixed paraplast sections, stained by the two step HRP-labelled antibody sandwich technique gave sufficient results for the demonstration and localization of CEA.