LIVE BLOG: Tips For Getting the Best Diagnosis From Your Dermatopathologist
In this Live Blog from the SDPA Summer Conference, we focus on dermatopathology. Dr. Sarah Walsh presents this lecture based off of her work in cutaneous pathology in St. Louis, Missouri.
This fascinating lecture is concerned with the ways to help give the best diagnosis by partering with your dermatopathologist.
How a Biopsy is Typically Processed
1. The Derm PA observers, for example, plaques on a patient’s buttocks.
2. The Request is made for pathological examination
3. The specimen is “grossed in”
4. Then it is processed over night: tissue is embedded in paraffin wax. That tissue then makes a block of wax.
5. Then that tissue in the wax is cut and put onto glass slides.
6. Slides are stains.
7. A diagnosis is made. In the case: Mycosis fungoides
Problems Pathologists Face
Recurring issues include:
+ Not enough history provided:
e.g. Single or multiple lesions? Prior treatment which included cryotherapy? Prior biopsy? (Sometimes scars from prior biopsies can mimic melanoma.) Is the patient pregnant? Has the patient had fillers in the areas of biopsy?
+ The tissue sample is insufficient!
+ Technique issues: careful not to squash punch biopsies with forceps; careful if cauterizing any tissue in which epidermis must be examined; tissue caught in lid
“Why is this Report Delayed?”
We all want to keep our patients from worrying, based on late-reports.
Reasons why a late-report often happens:
1. Likely a difficult case that needs more work: immunohistochemistry, special stains, or recuts.
2. Nail softening.
3. Waiting for outside slides/blocks/reports.
4. Attempts to obtain additional history from the submitting clinician.
5. Internal consult.
6. Technical problems.
Quick Tips: What Types of Biopsies to do When…
a. Mycosis fungoides- long thin shave
b. Nevus vs Melanoma- whatever can get you
the whole lesion (when possible)
c. Choose lesions in their diagnostic stage: ? Early- blisters, vasculitis?d. Late- psoriasis, discoid lupus, lichen planus
e. DIF- early lesions (24-48 hours) except for DLE- then old lesion (> 3 months)
f. Rash- punch usually
g. Dermal lesion- need dermis!
h. Panniculitis & morphea- need fat!
i. Alopecia- at least 4mm punch, nice to have 1 for vertical and 1 horizontal; Need Fat!
j. Biopsy a primary lesion and not a lichenified lesion or the center of an ulcerated lesion (unless PLEVA)
k. Mast cell disease or vitiligo- need bx of normal skin for control
l. Ideally, one specimen per container
m. If it doesn’t make sense, call or keep biopsying!
Communication and a good relationship between you and your dermatopathologist is most important
+ Don’t be afraid to call us!
+ Always challenge a diagnosis that contradicts your clinical impression, regardless of the reputation of the dermatopathologist
+ A good dermatopathologist should welcome the opportunity to correct a mistake and should thank you for saving his/her butt
In Summary, How Derm PAs can Help the Dermatopathologist
1. You don’t need to write a book, but be complete: history! history! history!
2. Fill out requisition completely.
3. Make sure there is a sufficient amount of tissue.
[image by EMSL]