Neoplasia Flashcards
1
Q
Types of Benign Tumors
A
- Adenoma = benign from epithelium
- Mucosa, epidermis and lining of glands
- Chondroma, fibroma, myoepothelioma
- Leiomyoma = smooth muscle cells
2
Q
Types of Malignant Tumors
A
- Carcinoma = metastatic from epithelium
- Mucosa, epidermis and lining of glands
- Mesothelioma = malignant from mesothelium (lines pleura, pericardium and peritoneum)
- Sarcoma= malignant from mesenchyme (connective tissue, bone, cartilage, vessels)
- Ex) osteosarcoma, chondrosarcoma, angiosarcoma
- Leukemia = malignant from WBCs
- Lymphoma = from lymph nodes
- Myeloma = from plasma cells
- Melanoma = from melanocytes
3
Q
2 Components of a Neoplasm
A
- 1- Parenchyma - actual proliferating cells; tumor itself
- 2- Stroma - intervening connective tissue, blood vessels, etc that SUPPORT tumor
- Can be desmoplastic (reactive stroma; white and fibrous w/o microscope, makes tumor more palpable; contains collagen, fibroblasts, blood vessels and chronic inflammatory cells)
4
Q
Carcinoma in Situ
A
- Epithelial neoplasm w/ all features of malignancies but has not started invading surrounding tissue yet
- Still bound by basement membrane
- Ex) CIN - cervical intraepithelial neoplasia ,PIN-prostatic, AIN-anal, VIN-vulvar, VAIN-vaginal, PANIN-pancreatic
5
Q
Polyp (+2 Types)
A
- Visible projection of collection of tissue above mucosa of an organ
- Projects into lumen
- Can be benign or malignant
- 2 Types
- 1- Pedunculated - polyp stands on stalk
- 2- Sessile - broad base that is raised above mucosa
6
Q
5 Plasia’s
A
- Euplasia- normal condition
- Hyperplasia - Inc # cells due to injury or growth stimulus
- Metaplasia - change from one cell type to another but same location
- Dysplasia - disordered growth; change in architecture, orientation and size of cells; pre-neoplasia so may remove to be cautious
- Anaplasia -backwards growth; pleomorphism and undifferentiated cells; characteristic of malignancy
7
Q
Morphology of Dysplasia (6)
A
- 1- hyperchromasia - extra dark staining in nucleus
- 2- inc nuclear:cytoplasm ratio
- 3- Clump chromatin pattern
- 4- Pleomorphism (diff sized cells - diff tomatoes)
- 5- Inc cell division so may see mitotic figures
- 6- Loss of normal polarity
8
Q
Teratoma
Hamartoma
Choristoma
A
- Teratoma - tumor of multiple embryological layers (not just one cell type -not clonal)
- From multi potential cells
- Mature (benign) v immature (malignant)
- Ex) dermoid cyst - mature cystic teratoma of ovary
- Hamartoma- benign collection of disorganized cells in NORMAL location that form tumor
- Choristoma - congenital abnormality; tumor of cells that are in location they would NOT NORMALLY be found (“heterotropic rest”)
- NOT METASTATIC - did not travel there from original site
9
Q
Features of Malignancy (8)
A
- 1- Autonomy - do not rely on normal growth signals (oncogenes)
- 2- Resistance - insensitive to growth inhibition (inactivation of tumor suppressor genes)
- 3- Altered cell metabolism - anaerobic glycolysis - for rapid cell growth
- 4- Evasion of apoptosis - normally disable the intrinsic/mitochondrial path of apoptosis
- Ex over-expressed BCL2
- 5- Replication - w/o senescence (can keep self-renewing w/o mitotic crisis)
- 6- Angiogenesis - tumor has own blood supply (hypoxia —> HIF-1alpha —> VEGF)
- 7- Invasion/metastasis - detach from one another and use collagenase and others to digest surrounding matrix
- Loosen cell-cell contacts
- Degrade ECM
- Attach to new ECM components
- Migrate
- 8- Escape host immunity and rejection
10
Q
How do malignancies escape immune system?
A
- Loss/reduction of MHC molecules
- Activate immunoregulatory paths
- Secrete immunosuppressive factors (ex - TGF-beta)
- Induce regulatory T cells
- Selective outgrowth of antigen-negative variants
11
Q
Examples of Oncogenes (9)
A
- Growth factors - FGF3
- Growth factor receptors - EGFR, Her2, JAK2
- Signal transduction proteins - RAS (GTP binding protein), ABL (non-receptor tyrosine kinase)
- Transcription activators - MYC and NMYC
- Cell cycle regulators - Cyclin-D1
12
Q
Examples of Tumor Suppressor Genes (6)
A
- p53- “guardian of genome” - normally arrests cell cycle
- APC - “adenomatous polyposis coli”- normally inhibits WNT which prevents beta-catenin from translocating to nucleus to turn on genes that promote cell cycle entry
- Rb1- “governor of proliferation” - cell cycle regulator; inactivated in retinoblastoma
- BRCA1/BRCA2- involved in DNA repair; familial breast and ovarian carcinoma
- VHL- inhibitors of pro-growth program of metabolism and angiogenesis
- CHD1- e-cadherin- inhibitor of invasion and metastasis
13
Q
Tumor Grade
A
- Look at…degree of differentiation, # mitotic figures under microscope, amount of tumor necrosis
- I II III IV or high grade v low grade
- G1- well differentiated TO G4 -undifferentiated
14
Q
Tumor Staging
A
- Combination of size of primary tumor, degree of lymph node metastasis, and degree of more distant metastasis
- UICC- # for ea T (tumor size) N (nodes) M (distant metastasis)
- T0 (no primary tumor) - T4a/b (extensive tumor invasion)
- N0 (no regional lymph node metastasis) TO N2b (7+ nodes)
- M0 (no distant metastasis) TO M1c
- AJCC- 1 # that combines all of these factors
15
Q
Cachexia
A
- general loss of body mass b/c inc in overall metabolism
