Neoplasia 1 Flashcards
Adenoma
Benign epithelial tumor of the glands
Papilloma
Benign epithelial tumor of skin; projects outwards
Polyp
Benign epithelial tumor of mucosal surface (GI tract, nasal cavity, etc.)
Carcinoma
Malignant epithelial tumor
Describe the shape of epithelial tumor cells
Polygonal, cuboidal, or columnar
Describe the arrangement of epithelial tumor cells
Group together: nests, cords, islands, acini/tubular/glandular structures
Schirrous/desmoplastic reaction
Firm growth caused by normal fibroblasts “turned on” by tumor
Sign of EPITHELIAL tumor
Carcinoma in situ
Carcinoma that does not penetrate the basement membrane
Tissues derived from ectoderm
Skin (epidermis) Lining (nose, mouth, and anus) Eye Enamel Mammary gland Pituitary and pineal glands Inner ear Nerves Medulla of adrenal gland
Seven Little Elephants Eat Many Peanuts In Nine Minutes
Tissues derived from mesoderm
Dermis Notochord Fat Muscle Reproductive system Dentin (teeth) Urinary system Skeleton Blood Connective tissue
Do Not Feed Mangy Rabid Dogs Unless Surrounded By Canines
Tissues derived from endoderm
Thymus Pancreas Auditory tube Liver Prostate G.I. tract Respiratory (including lung) Thyroid
Tall People and Little People Get In Relationships Together
Where do squamous cell carcinomas occur? Describe their gross and histological appearance.
Locations: Cat tongue and squamous part of horse stomach
Gross appearance:
- Lobular
- Angry red color on tongue (ulceration)
Histological appearance:
- Keratin pearls: dark pink “bulls-eye” w/ few nuclei
Cytokeratins
- Intermediate filaments in epithelial cells
- Stain BROWN by immunohistochemistry
Three histological features of mesenchymal tumors
- Spindle-shaped cells
- Arranged in streams, bundles, and whorls
- Produce stroma/matrix (osteoid, chondroid, collagen) IF BENIGN
“Hemangio-“
Endothelium
“Leiomyo-“
Smooth muscle
“Rhabdomyo-“
Skeletal muscle
“Soft tissue sarcomas”
Perivascular and/or perineurial
Compare and contrast malignant vs benign mesenchymal tumors
Malignant = many cells, little stroma Benign = few cells, extensive stroma
Vimentin
- Intermediate filaments of mesenchymal cells
- MAY be found in some epithelial cells; poor specificity
Desmin, actin, and myosin are found in
Muscles
Alkaline Phosphatase is found in
osteosarcoma
Factor-8 and CD-31 are found in
endothelial cells
Which 2 types of “-omas” are ALWAYS malignant (even without “-sarc-“)?
Lymphoma and melanoma
Which type of round cell tumor does not lack stroma?
Transmissible venereal tumor
How can a mast cell tumor be identified?
Stains:
- Giemsa
- Toluidine blue
Marker:
- C-kit (growth factor receptor)
Marker for T lymphocytes
CD3 (part of receptor)
Marker for B lymphocytes
All: CD79a (part of receptor)
Plasma cells: Mum-1 (transcription factor)
Markers for histiocytes
CD18 (adhesion molecule)
Iba-1 (involved in phagocytosis)
Markers for melano(cyt)oma
PNL-2 (regulates pigmentation)
Melan A
Where are mixed epithelial and mesenchymal tumors commonly found?
Mammary glands
Describe malanocytic neoplasms
- Spindle, polygonal, or round (rare) cells
- Stream, packet, or sheet architecture
- Epitheliotropism: enter epithelium
Which neoplasm types tend to be soft?
Lymphoma, lipoma
Which neoplasm types tend to be firm?
Carcinoma, sarcoma, fibroma
Five characteristics of malignancy:
- Differentiation and anaplasia
- Necrosis
- Loss of function
- Invasiveness
- Metastasis
