2.9, 2.10 Cytology Flashcards
which organs are readily accessible for cytology
lymph nodes, liver, kidneys
what is important to consider before doing cytology of any tissue
whether the tissue has a characteristic cytological appearance
what would prompt you to do cytology of a lymph node
swelling, pain, to do a metastasis check
what 3 reasons can explain an enlarged lymph node
hyperplasia, inflammation, neoplasia
lymphocytes are (hardy/fragile)
fragile
what percentage of a normal lymph node consists of small lymphocytes
70-90%
T/F small, medium and large lymphocytes are all present in a normal lymph node
T
what cell types are present in the normal lymph node
lymphocytes (all sizes), plasma cells, macrophages, some neutrophils, eosinophils, mast cells
what causes reactive hyperplasia (reactive lymph nodes)
antigenic stimulation in the area of drainage
reactive hyperplasia is characterized by (2)
an increase in the number of large lymphocytes and plasma cells
chronic stimulation of lymph nodes results in what change
Russell bodies inside of plasma cells (Mott cells)
what are Mott cells and the Russell bodies they contain
Mott cells are plasma cells full of immunoglobulin. The Russell bodies are aggregates of immunoglobulin
under what condition would a lymph node be painful on palpation
lymphadenitis
lymphadenitis is characterized by (3)
an increase in neutrophils, eosinophils or macrophages
mycobacterial infection typically causes ________________ inflammation, which is characterized by _______ cells
granulomatous; giant
what is lymphoma
malignant neoplasm of lymphocytes; homogenous population of lymphocytes
lymphoma is characterized by ________ in all species; __________ in cats and horses and _____________ in dogs
mitotic figures; mixed size of lymphocytes; large lymphocytes
T/F most lymphomas are not treatable in small animals
F
what types of cancer can metastasize to the lymph nodes? give some examples
potentially any malignant tumor can metastasize to lymph nodes; mast cell tumors, malignant histiocytic sarcomas, melanoma, carcinomas
when considering the cytology of cancer, it is important to distinguish __________ from _________
hyperplasia from neoplasia
cancer cytology is best combined with
histopathology
what are the 3 cytological classifications of cancer
1) epithelial
2) mesenchymal (spindle cell, stromal cell)
3) round cell
what are 2 characteristics of epithelial neoplasms
cells adhere to one another (sheets, clumps, tubules, acini); cell borders are apparent
what are 2 characteristics of mesenchymal cell neoplasms
indistinct cytoplasmic boundaries; long cytoplasmic tails or spindles
soft tissue sarcoma, fibroma, hemangiosarcoma, osteosarcoma, chrondrosarcoma are all cancers of
mesenchymal cells
what are 2 characteristics of round cell neoplasms
round shape and nucleus; cells do not adhere to one another
histiocytoma, melanoma, plasmocytoma are all cancers of
round cells
what are the 5 cytological features of cancer
1) size
2) nuclear enlargement (increased N/C ratio)
3) nucleolus number and size
4) mitotic figures
5) hyperchromasia