Paraffin Embedded Breast Carcinomas for the Immunohistochemical Study of Prognostic Factors

There is increasing evidence that prognostic markers, including steroid receptors (estrogen and progesterone), estrogen-regulated proteins (pS2 and cathepsin-D), proliferation markers (proliferating cell nuclear antigen), and growth factors (epidermal growth factor receptor) can beuseful in the management of patients with breast cancer. However, a full panel of assays would need a large sample of biopsy tissue, and increasing public awareness of the need for early detection has resulted in a continuous decrease in size of individual biopsies. Commercial antibodies that perform on routine paraffin sections have now made it practical to perform an array of immunohistochemical assays on paraffin embedded tissue. Our experience with the routinely processed biopsies of 27 patients provides convincing evidence of the feasibility of determining some of the more widely used prognostic markers in breast cancer from a single paraffin block. (The J Histotechnol 15:315, 1992)