Immunohistochemistry on frozen section of sentinel lymph nodes in breast cancer with improved morphology and blocking of endogenous peroxidase.

Sentinel lymph node biopsy in the management of patients with breast cancer is the clinical practice. Peroperative examination means that more patients can be treated in a 1-step procedure. The addition of immunohistochemistry to frozen section slides improves the detection rate of especially micrometastasis. We present a novel method for immunohistochemical staining on a frozen section material that gives better morphology and blocks endogenous peroxidase sufficiently.