Anatomic Pathology Flashcards
What is diagnostic pathology?
Clinical pathology, histopathology, bacteriology, virology, serology, molecular diagnostics, electron microscopy, toxicology
What are the two arms of diagnostic pathology?
Clinical and anatomic
What is considered clinical pathology?
-Analysis of bodily fluids via biochemical analysis: blood, urine and effusion
-Cytology: FNA, Smears, Individual cells, quick and less intrusive, not always definitive and cant always grade
What is considered anatomic pathology?
Morphologic evaluation - gross and microscopic
-Tissue, patterns, cell and adjacent tissue, longer turn around, more invasive, anesthesia, more definitive, grade, count, immunichem
-mass/tissue/architecture
If you need your result back quickly which of the two types of pathology would be most ideal to use?
Clinical - blood and cells can be analyzed in 1-4 hours, less intrusive
If you have time to wait what type of pathology could you use?
Anatomic - minimum of 2 days to fix and process it
What are reasons you may take a tissue sample?
-Initial treatment was unsuccessful
-determine if it was cancer or not
-confirm a presumptive diagnosis
-differentiate amongst rule outs,
-cytology non-diagnostic or equivocal
-ultimate cause of death or disease
-Rule out disease
What are some of the top considerations in sample collection?
Location, size and number
Describe the optimal location to take a sample from a lesion:
Not directly in the issue (may just be necrosed cells), not in the fully normal (normal), need to be at the division and get some of each if possible (interface) - can see how cells are itneracting
How big should your sample be?
Bigger is better!
-Punch, skin, incisional biopsy, mass
-Less susceptible to artifact
How many samples should you take?
The more the merrier and get them from various areas
-Submit them call, never know which one will tell the story
Why do we perform a necropsy?
-Sudden Death
-Clinical diagnosis
-Treatment failure
-extent of disease
-cataloging disease
-herd health implications
-teaching and research
-closure
What are some keys to performing a quality necropsy?
-Consistent technique
-Completeness (more than interest area)
-Adequate and appropriate sampling
-Fresh/Formalin (Culture and serology)
-Clean tissue, then finish with GIT
-Dont handle mucosal side, handle serosal
-No clamp down hard with forceps
-submit placenta with fetal tissue
-Bread loaf large (get formalin all the way through)
-Report/describe well
What organs should you sample?
Lungs, liver, kidney, spleen, small intestine, large intestine and heart
What size should your samples be?
<1cm or starburst size
What should the tissue to formalin ratio be?
1:10 Tissue to formalin
What if your sample is larger?
Bread loaf it and place markers to differentiae which side
What should you not do?
-Place a giant organ in a little formalin
-Place a giant organ not bread loafed
-put it in a container that is not approved by the lab
-Roll up skin…
What should always accompany a sample?
A lab submission form
-Have your info on it, owners, good history helps, location of lesion very helpful
How is tissue processed?
-Technician cuts it up and measures it into little cassettes (2 x 1 x 5)
-Placed in machine to be processed dehydrated and paraffin put on it to maintain stiffness, trim to put on slide (48hr)
-Use razor blade to put in fine section
-Give to pathologist to analyze
What is provided in the pathology report?
Clinical history, specimen site, gross description, microscopic description, diagnosis, comments, pathologist signature
Diagnosis and comments critical
Is there a standardized approach to getting complete margins of excision of tumors?
No - use paint or sutures
-Bread loaf every 2cm
-Cross section through mass
(assume symmetrical so margins may not be complete)
What are the components of the morphologic diagnosis?
Process - inflammation, necrosis, hypertrophy
Chronicity or Timeframe - acute, chronic
Distribution - difuse, milliary, segmental, locally invasive or extensive
Organ - which
Severity - how bad
