Histopathology

Specimens should routinely be fixed in formalin (10% neutral buffered formalin solution). Labelled specimen containers of various sizes containing formalin are provided by the laboratory to all users upon request. All tissue samples should be placed in fixative as soon as possible after removal from the patient. It is important not to let the specimen dry out (this can be a particular problem with small biopsies). The recommended volume of fixative is at least ten times the volume of the specimen, so it is important not to place a specimen into too small a container. If in doubt, choose a larger container. Poor fixation can hinder or prevent accurate histological diagnosis. The temptation to slice open or dissect an excised specimen before it is sent to the histopathology department should be resisted. Subsequent fixation of a partly incised specimen may cause distortion and hinder anatomical orientation. In the case of excised tumours, it may then be impossible to identify surgical planes of excision. Containers of formalin should be securely closed and transport should be in line with the Trust Policy on the transport of specimens in formalin. Formaldehyde vapour is a well-recognised respiratory irritant. Skin contact with formalin solution should be avoided, as repeated exposure may cause dermatitis in some individuals. Formalin spillage kits should be available to each department that stores formalin. Specimens from GPs: Specimens should be placed in a formalin filled specimen pot and the lid should be properly secured. The specimen should then be placed in a leak proof bag for transport to the Histology Department via the Pathology courier.