Cytopathology of Round Cell Neoplasia Flashcards
What are properties of round cells?
also called discrete tumors
round, discrete cellular shape
What are the types of round cells?
lymphoma
mast cell tumor
plasma cell tumor
TVT
histiocytic tumors
What does lymphoma typically present as?
lymphadenopathy
What origin is lymphoma from? Which form is the most common?
typically from B or T cell origin
large cell lymphoma
Which lymphoma is common with feline GI lymphoma?
small cell lymphoma
How do you base lymphocytes on size?
What can also be present in lymphoma?
lymphoglandular bodies - cytoplasmic fragments of ruptured lymphocytes
almost look like platelets
What are these?
lymphoglandular bodies
fragments floating around
Small-medium sized lymphoma can be difficult to distinguish from _____
reactive tissue - may need histopathology or PARR
Normal or abnormal?
normal lymph node aspirate
Classify this
large cell lymphoma
What characteristics of malignancy are there? What is this?
multiple nucleoli, 2 nuclei
large cell lymphoma - 2-3x bigger than red blood cells
What are the characteristics of mast cell tumors?
cutaneous vs. subcutaneous
How do mast cells typically appear on dogs?
commonly hairless, raised, solitary nodule/mass | trunk and limbs
How do mast cells typically appear on cats?
solitary, well-circumscribed nodule on head, neck, limbs; multiple at one time
How do mast cells appear on slides?
consists mostly or entirely of mast cells (only tumor to do this)
granules can vary in number
nucleus may be difficult to see due to darkly stained granules
What are mast cell tumors’ potential?
potential to metastasize
all need removal with wide excision and histopathology - low vs high grade (high = more atypia, more mitotic figures, etc)
Type?
mast cell tumor
Type?
mast cell tumor
Type? List characteristics
large cells, varying shapes, fine granules in cytoplasm, granular rupture
Type?
mast cell tumor
What are the types of plasma cell tumors?
- extramedullary plasmacytoma
- multiple myeloma
- osseous plasmacytoma
Where are extramedullary plasmacytomas commonly found?
typically localized to single lesion/site (cutaneous, oral)
solitary, pink, alopecic-ulcerated mass/nodule
Extramedullary plasmacytomas are usually [benign/malignant]
benign - but locally aggressive
How do extra medullary plasmacytomas appear on microscopy?
appear as normal plasma cells
eccentric nucleus that is round and small
may see criteria of malignancy
Type?
plasmacytoma
Type?
plasmacytoma
What cell can you see in plasmacytomas?
Mott cells
What is multiple myeloma?
malignancy arising from plasma cells
clonal proliferation and infiltration of plasma cells in BM
neoplastic cells secrete Ig protein - hyperviscosity syndrome due to excess circulating protein
What are characteristics of TVTs?
highly contagious and may regress
Type?
TVT
What are the characteristics of a cutaneous histiocytoma?
benign, dendritic cell origin, rapidly growing
usually regress spontaneously within 3 months
How does cutaneous histocytoma appear microscopically?
M-sized cells, may be indented/bean shaped
moderate light blue/gray cytoplasm
What indicated regression with a cutaneous histiocytoma?
small lymphocytes
Type?
cutaneous histiocytoma
What is this?
regressing histiocytoma
What is a histiocytic sarcoma?
proliferation of interstitial dendritic cells
localized vs disseminated
What is a localized histiocytic sarcoma?
single tissue or organ affected
firm purple/red nodules/masses on extremities and around joints most often
locally invasive, metastasis to draining LN
What is a disseminated histiocytic sarcoma?
once metastasizes past LN to distant sites
previously called malignant histiocytosis
Suspicion?
histiocytic sarcoma
What is cytology of histiocytic sarcoma look like?
sheets of large, pleomorphic, mononuclear, and MNGCs
can appear as spindle-shaped
