Frozen section

Fresh tissue transported immediately to the laboratory. 

Clinical inflammation is essential and ideally laboratory staff should be consulted prior to specimen submission.

Fresh tissue is examined upon arrival in the laboratory. 

Suitable sections are taken, frozen and sectioned in a freezing microtome. 

Following staining sections are examined by a pathologist and, where appropriate, the diagnosis is immediately conveyed to the operating surgeon.

Intra-operative diagnosis is usual to confirm or exclude malignancy or for identification of normal tissue (parathyroid gland, lymph node) in order to inform subsequent surgical management. 

Frozen sections may also be used to examine tissue from the surgical margins for completeness of excision. 

Examination of fresh tissue may permit selection of appropriate ancillary investigations, such as EM, IF or IH.

Assessment and diagnosis by pathologist. 

Tissues are then usually fixed for routine processing.