CPD ACCREDITED ARTICLE
Size
The single most important variable affecting the
likelihood of getting a diagnostic biopsy is specimen
size. Small specimens (endoscopic, rhinoscopic,
Tru-cut etc.) are highly susceptible to crush artefact.
Because such small pieces of tissue may not include
diagnostic tissue and in addition can be a challenge
to properly orientate in the cassette, very small pieces
often produce non-diagnostic biopsies.
Large specimens such as amputations, splenectomy’s,
large subcutaneous masses etc. resist crush artefacts,
but are susceptible to poor fixation. It is important to
bread slice such large specimens and then select the
interface between abnormal and normal tissue and
then subsample different looking areas of tissue for
submission. As a general rule the larger the mass the
more subsample should be taken. Splenic masses
should include at least 4 to 6 pieces.
The margin principal
Surgeons should always tag what margin is important
and note this on the submission form. A common
problem is when multiple masses are included in the
same jar without being marked.
Signalment, history and description of the lesions
Histopathology evaluates only a tiny fraction of the
affected tissue. In order to fully orientate pathologist
and facilitate a total patient evaluation, clinicians
and the practice staff must describe what they saw.
Descriptive pathology is a skill that veterinarians
obtained from vet school, but these skills are
frequently lost due to disuse. Again, this comes back
to poor communication between pathologists and
clinicians, which ignores the important principles that
descriptive pathology provides to both parties. With
the emergence of sophisticated imaging techniques,
clinicians are starting to see the value of descriptive
pathology skills. What clinicians see is extremely
important in case management and of enormous
value to the pathologist in interpreting their biopsies.
Pathology is not just for autopsies and it’s not just for
pathologists anymore either.
lead them into making the wrong diagnosis. Digital
pathology has provided clinicians with a very useful
and helpful tool to assist with gross description of the
lesions.
Signalment and history
Many clinicians are still under the wrong impression
that if they tell the pathologist anything it will bias him
or her in their decisions. Such an approach frequently
leads to serious errors in medical judgment and
mis-diagnosis. If the goal of the biopsy is to fool the
pathologist, then tell them nothing. If the goal of the
biopsy is to get an accurate diagnosis quickly then tell
the pathologists what you know or think.
The submission form
This is a critical document in solving many of the
communication problems of surgical pathology. A
good form is one that is 100% dedicated to the biopsy.
Remember on this form to give your pathologists the
what 4!!
•
•
•
•
What did you see?
What did you do?
What do you think?
What do you want?
The 5 important descriptive elements that should be
included on every oncology submission form are the
following:
1. Signalment – species, age, breed, sex (intact or
not).
2. Clinical or historical daughter – pertinent to the
case, brief and to the point (1 to 2 lines).
3. Precise location of the lesion or origin of the
sample.
4. Descriptive characteristics – size, colour, shape,
distribution.
5. Clinicians thoughts – differential diagnoses, rule
out’s.
References
1.
King J M, Roth, L, Dodd, D C & Newson, M E. 2005. The Necrop-
sy Book. 4th edn, Charles Louis Davis Foundation of Comparative
Descriptive pathology for biopsy specimens
The purpose of the gross description in surgical
pathology is to orientate the pathologist reading the
histopathology slide and to verify what was received
at the laboratory. Description should be brief and
to the point and include information pertaining to
size, colour, location and distribution. Remember to
describe what you see as though you were speaking
to a blind person, because effectively the pathologist
is unsighted to what you are seeing on the patient.
Take photographs and attach to the request. If you
do not share this information with them, you may
Pathology, Washington.
2.
Maxie, M G. 2016. Pathology of Domestic Animals. 6th edn.
Saunders Elsevier, St Louis.
3.
McGavin, M D & Zachary, J F. 2016. Pathologic Basis of Veteri-
nary Disease. 6th edn. Mosby Elsevier, St Louis.
4.
Meuten D J. 2017. Tumours in domestic animals 5th edition. Wiley
Blackwell, Ames, Iowa.
5.
Stromberg P C. 2009. The principles and practice of veterinary
surgical pathology. Charles Louis Davis Foundation of Compara-
tive Pathology and American College of Veterinary Pathologists.
Monterey, California.
Issue 04 | SEPTEMBER 2018 | 7