Lecture 6 2/10/25 Flashcards
Why is species important to indicate when submitting tissue to a pathologist?
differences that occur between species; i.e. spindle cell proliferation in dogs vs cats vs horses
Which cancer is predisposed in norwegian elkhounds?
infundibular keratinizing acanthoma
Why is breed important to indicate when submitting tissue to a pathologist?
there are many breed predispositions for neoplasia; it can help point the pathologist in the right direction
Why is color important to indicate when submitting tissue to a pathologist?
-white cats often get squamous cell carcinoma
-white dogs often get dermal hemangioma
-large breed black dogs often get multiple digital squamous cell carcinoma
-other predispositions based on coat color
Why is age important to indicate when submitting tissue to a pathologist?
histiocytomas are common benign skin tumors in young dogs; helps pathologists consider rule ins and outs based on age
Why is sex and alteration status important to indicate when submitting tissue to a pathologist?
-mammary and perianal tumors, as well as others, are more hormone responsive than other tumors
-intact animals can have cancer of the reproductive tissues
What descriptive factors should be included in a pathology submission form?
-size in metric units
-color
-location; very specific
-distribution
-mass vs. other tissue
Why is it important to be specific with lesion location?
-need to indicate whether a lesion is on the skin or within a cavity
-different locations on the same part of the body (i.e. interdigital vs pad vs subungual) can have different predisposed conditions
-some tissues provide better prognosis than others (lip vs oral - lip is better)
-not all tissue is the same within the same area of the body; not all oral tissue is gingiva, changes the best fitting diagnoses
What are the characteristics of lesion distribution?
-very important for dermatology cases
-want to be more descriptive than generalized; indicate more specific locations
-be more descriptive than just “face” by indicating specific location within that portion of the body
-describe symmetry
Why is it important to indicate whether the tissue being submitted is thought to be a mass?
normal adipose tissue and lipomas look identical histologically; knowing where the collected tissue came from helps make the correct diagnoses
What aspects of treatment should be included in a pathology submission?
-drugs involved; they could affect tissue histopathology
-response to treatment
-time since last treatment
What aspects of sampling technique should be included in a pathology submission?
-whether local or general anesthesia was used
-sampling technique; endoscopic, tru-cut, wedge biopsy, etc.
-whether the biopsy was incisional or excisional
Why is it important to include your own thoughts regarding a submitted sample?
-submitting veterinarian’s thoughts are very important; they get to see the entire patient and other results
-pathologist’s findings are just one component of case interpretation
What are the “what fours” of pathology submission?
-what did you see?
-what did you do?
-what do you think?
-what do you want?
What are the challenges that can prevent diagnosis?
-biopsies from multiple locations in one container
-insufficient formalin
-jars with necks
-leaky containers
-compression artifact
-partial lymph nodes
-drying artifact
-tiny specimens
-orientation not being indicated
-granulation tissue vs sarcoma recurrence
What are the important aspects of biopsy margins?
-ink the margins; preferably green or blue
-only put ink on surgical margins, not ulcerations
-ink tissue prior to fixation
-let ink dry before submerging in formalin
-do not cut surgical margins
-do not use laser or cautery on margins/submitted tissue
-intravascular tumor trumps margins; can still spread with clean margins
-do not ask for margin evaluation on diffuse lesions
How can a pathologist address prognosis?
-they can provide information from current literature on some tumor types regarding progression/aggressiveness/etc
-they cannot give treatment suggestions/information
What are the characteristics of diagnostic accuracy?
-length of comment is often inversely proportional to confidence in diagnosis
-consultation with other pathologists often indicates less confidence in diagnosis/not as easy to diagnose
How many days does a typical biopsy take to be evaluated?
2 days with a stat consult, 3 days with a routine consult
Why does a typical biopsy always require at least 2 days?
tissue must spend an overnight in a tissue processor to remove water from the tissue
What aspect of a routine consult is removed in a stat consult?
evaluation by a resident pathologist
What can cause delay in biopsy evaluation?
-unfixed specimens
-unlabeled specimens
-consultation with other pathologists
-special stains
-decalcification
How should bony legions/specimens be handled?
-loose teeth do not need to be submitted
-submit whole legs fresh
-inked margins are helpful on bony specimens
