PLEASE READ THE DISCLAIMER:
The info shared here is by no way an absolute method to do breast tumor mapping. I have skipped some technical parts in order to give the reader a gist of how it is done. The method of dissection can vary depending on the reference material used and new methods of dissection can change as the art of dissection also evolves. Do not use this post thinking it's a proper reference material. If you need to know the academic resource, you can try reading Manual of Surgical Pathology by Lester. It's my bible for dissection.
I'm still hoping for the day where real medical professionals get onboarded and we start a niche community for conventional medicine. That being said, the stuff shared on this post is niche content even under the niche of conventional medicine.
Tumor mapping is done to map out the extent of the tumor spread. It's usually done after other therapeutic interventions have been tried like the patient complying with a series of chemotherapy cycles. It's done to evaluate how effective initial treatment is and to assess extent of relapse if tumor has recurred. It helps get give the clinician an idea of how current prognosis of the patient.
This is a an underside of part of the left breast from a patient that ahs undergone modified radical mastectomy. If you notice that small knob on the upper left side, that's the axillary tail where lymph nodes can be extracted to assess for extent of tumor spread and helps with the staging. If simple mastectomy was done, no axillary tail should be expected in the specimen sent.
S: Superior
M: Medial
L: Lateral
I: Inferior
There is a B for Basal side which is the underside margin. The triangle portion is the axilla. For this view, we're looking at the right breast specimen. The lower breast is viewed from the medial side.
Let's just pretend the red part is the tumor. It's measured in three dimensions, length, width and depth.
The blue lines represent how it is being cut like a bread loaf to assess the extent. The lower part is a cut section of a slice of the bread load.
The green part is the slab cut and when viewed at the side you get the image on the lower part. The widest part gets cut into pieces and labeled by corresponding letters and digits to have a landmark.
It will be processed into their respective slides and would look like this. Each slide will be looked into assessing for the degree of necrosis (how much tumor cells died and are still viable), other histologic details include extent of spread and changes. There's computing the residual tumor burden and how much it affects the prognosis but that's another story which you wont really have any practical use knowing right now.
The green parts are sections also taken for assessing the margins. Whether the tumor has reached those areas too. If they do, it means there are residual tumor cells left within the patient.
Hope you learned something. If you want a sample of a detailed version, try reading Bone Tumor Dissection.
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