The Nelson laboratory receives a large number of skin excision specimens for various type of lesion. Many of these come with orientation markers, which places an increased workload on the laboratory, and with the large volume of skin specimens, this can quickly become unmanageable. To try to reduce unnecessary work, the laboratory requests referrers consider the following recommendations.
The laboratory protocols for when an orientation marker is present, are much more time consuming, as well as using up more resources and consumables. This is because the different edges require differential inking, and a more complex cut up description. They also usually require more blocks to be used, which in turn mean they each use up more consumables, space on the processors, and take more time to handle manually at all stages through the laboratory. This finally results in more slides going to the pathologist and an increased time at reporting to determine the different margins, that in the wider picture, may not make a difference to the clinical management.
We understand there are certain sensitive anatomical locations where orientation is entirely appropriate (ie in some cases from around the face and ears). However, there are many instances where sites outside of this area are received with orientation. In almost all of these cases, orientation markers are not helpful to the pathologist. If orientation is not required clinically, then it is not required by the pathologist (although we realise there may be rare exceptions to this rule). For cases proceeding to re-excision, we usually receive specimens with the entire scar re-excised including skin to both sides of it, meaning that the re-excision management has been the same, regardless of whether the first specimen was orientated or not.
Therefore, the laboratory would appreciate it, if referrers could limit orientation of skin specimens to those specimens from the face and ear area where it is required, and in the rare exceptions at other sites where it will make a difference to clinical management.
Finally, if orientation is required, we would strongly encourage the use of a single suture, tied loosely to create a loop at the appropriate edge of the specimen (for an ellipse, the corner is preferred). If orientated, then it is essential for an orientation key to be provided on the request form. Tightly tied sutures should be avoided as these can be difficult to remove without damage to the margin. Please refrain from scoring or notching specimens. Scores are not always visible after tissue shrinkage (fixation), and large notches create problems with the integrity of the tissue, compromising margin assessment.
Quick reference guide for skin excision orientation:
- Limit to some face and ear area excisions where specific margin knowledge will change how any re-excision is handled.
- If orientating a specimen use a single suture securely tied into a loop (multiple sutures are not required).
- Avoid using notches (destroys integrity of tissue and lesion).
- Avoid tight sutures ties to skin (destroys skin integrity during removal of suture).
- Provide a clear and legible orientation key on the request form.
If you require further information or clarification please contact Dr Jeremy Hyde, Anatomical Pathologist, Nelson – jeremy.hyde@awanuilabs.co.nz
Your assistance in this matter is greatly appreciated.