Send tissue in 10% buffered formalin. Source is required on sample and requisition. If multiple sources, send one container per source.
Small biopsy specimens are to be placed immediately in 10% formalin solution. Use approximately 10 to 20 times as much formalin solution as the bulk of the tissue. Small tissues such as those from bronchoscopic biopsy, bladder biopsy, and endometrium can be compromised in a short time by placing in saline or allowing to dry. Organ and larger tissue resections are to be placed in larger containers and covered with adequate amounts of formalin. Specimens such as colons, urinary bladders, and uteri require opening to expose the mucosal surfaces to formalin. Gallbladders undergo rapid degeneration; therefore, they require immediate fixation in 10% formalin solution; an incision made in the gallbladder will aid in more rapid fixation.
Indefinite once preserved in formalin
5-7 days, 7-14 days if oral source