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I. Local excision specimens:
Key to the handling of
polyps is to provide a block that ensures a complete section through its
stalk, base and head.
-Small polyps - embedded whole.
-Lesions less than 1cm - bisection through the stalk
-Lesions more than 1cm - (see diagram). Edges should be trimmed. There
should be three pieces.
The central section contain the intact stalk. The two side pieces are
put into a separate cassette.
At least three levels are cut from a small polyp and six or more from a
larger polyp.
II Submucosal polypectomies and transanal
full thickness local excision specimens:
Indication: 1. In cases of large
adenomas and early carcinomas. 2. Performed as palliative procedure in
patients unsuitable for more radical surgery
Specimen: Both types of specimens
consist of a lesion with narrow rim of surrounding normal tissue.
Procedure:
(see diagram)
1.For proper examination
the fresh specimen needs to be pinned around the entire circumference
and fixed for at least 24hrs.
(Note: Fixing of specimen without pinning can cause tissue shrinkage.It
becomes difficult to orientate the specimen and assess the resection
margins.)
2.Next specimen margins
are identified with coloured markers.
3.The whole specimen is transversely sectioned into 3mm slices and
submitted for histology in sequentially labelled cassettes.
4. In specimens where the margin of normal tissue is less than 3mm, a
10mm slice containing the relevant margin should be made a and further
sectioned at right angles as shown in the diagram.
III Sampling of multiple
polyps and polyposis:
Multiple adenomatous and
metaplastic polyps may be present in the backround of colorectal
resections performed for both neoplastic and non-neoplastic lesions and
in polyposis syndromes.
All polyps under 1cm
in a colectomy specimen do not necessarily need to be sampled.
All suspected adenomas above 1 cm
in diameter should be submitted for histology.
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