Histopathology

Collection & Type of Biopsy Specimens

Fixative:

Surgical specimens after removal should be placed in an adequate quantity of fixative (10% formal saline) as soon as possible. For optimal fixation a piece of tissue should be immersed in at least 10 times its own volume of fixative.

Containers:

Jars or bottles with screw tops and of suitable capacity should be used. Large specimens should not be squeezed into a smaller container. This will result in inadequate fixation and will allow autolysis to proceed unchecked. The subsequent interpretation of microscopic appearances may thus be made difficult or impossible. If a specimen is too large to fit easily into the largest size of container it should be brought as such to the laboratory without delay in a bucket or other suitable container. Amputated limbs may be wrapped in a rubber sheet. Bulky solid specimens, e.g., large tumours, spleen, etc. should be bisected cleanly with a large sharp knife before being placed in fixative. Hollow viscera such as portions of stomach and intestine should be opened at both ends or cut open along their length (stomach should be opened along the greater curvature). If, for any reason, jars of fixative are not available, the specimen should be taken fresh to the laboratory or wrapped in moist cotton wool and put in the refrigerator overnight. The specimen should never be put into water or normal saline because this will hasten autolysis.

Rapid Frozen Section:

If a rapid frozen section is required the laboratory staff and pathologist must be notified at least 1 hour before the time of the operation and preferably on the preceding day. Arrangements should also be made to notify the laboratory as soon as the patient is taken into the theatre for the start of the operation. The specimen must not be put into a fixative but be brought with the least possible delay to the laboratory. If after the start of the operation, the surgeon decides that a rapid frozen section is unnecessary the laboratory should be notified at once.

Request Forms:

If more than one biopsy is taken from the same patient at the same time, a single request form will suffice for all those specimens relating to a single pathological lesion. If two or more apparently unrelated pathological lesions are biopsied from the same patient, separate forms should accompany each specimen. If previous specimens from the same patient have been sent to the laboratory, this fact should be stated on the form together with the approximate date of previous histological examination. If this was done in another laboratory, this fact should also be clearly stated. The medical officer in charge of the case must complete the forms. Apart from the usual particulars required on any request form the clinical data must include any specific information contributing or relating to the present illness. In surgical cases the following additional information is required:

Precise nature of the operation performed.
Whether the entire specimen or only a part of it is being sent to the laboratory.

Labelling of Specimen:

It is the responsibility of the Medical Officer to see that the specimens are correctly labelled, including the name of the patient, ward, hospital and specimen; with date and time of obtaining the specimen. These particulars should tally with those stated in the accompanying request form.

Renal Biopsy:

The specimen of renal biopsy for histopathological examination should be collected in 10% formal saline. The request form should contain all the relevant clinical information and results of laboratory investigations. The specimen of renal biopsy for immunofluorescence should be submitted fresh in normal saline.

Liver Biopsy:

The liver biopsy specimen should be collected in 10% formalin/formal saline. Request form should mention the reports of LFTs and hepatitis markers tested besides the relevant clinical information. Liver biopsy specimen for the diagnosis of storage disorders should be collected in absolute alcohol.

Bone Specimen:

Bone specimen should be collected in 10% formal saline. Information regarding age, sex of the patient, site of biopsy, clinical history and x-ray with radiologists opinion are required for reporting on bone specimens and should accompany the specimen.

Specimen for Immunohistochemistry and Tumour Markers:

Specimens should be collected in 10% formal saline. If the case has been reported from AFIP initially, then AFIP report No. is also required. If the case is reported by some other laboratory, then all the slides along with paraffin embedded blocks and the histopathology report are required for immunohistochemistry and tumour markers.

Specimen for Oestrogen and Progesterone Markers:

These markers are carried out on paraffin blocks. Paraffin blocks along with previous slides and report are required if the case has been reported from some other laboratory.