Ch 7 Flashcards
What is desmoplasia
Parenchymal component stimulates abundant collagenous stroma eg choliangcarcinoma, breast
What are benign tumours
Localised at site of origin, amenable to surgical removal, usually has ‘oma’ in name eg fibroma
Malignant tumours arising from mesenchymal cells are called
Sarcomas
What are mixed tumours?
Tumours that have more than one line of differentiation eg derived from more than one germ layer
What are exceptions to ‘oma’ rule 5
Sarcoma
Melanoma
Mesothelioma
Lymphoma
Seminoma
What is a Hamartoma
Abnormal tissue present in a normal anatomical site; disorganised masses of cells indigenous to involved tissue
A benign neoplasm
What is a choristoma?
Reverse hamartoma: normal tissue at ABNORMAL tissue site. Ectopic of normal tissue. Non neoplastic
Eg normally organised pancreatic tissue in submucosa of stomach
What is tumour differentiation?
Degree of which the tissue resembles tissue of origin morphologically and functionally eg poor means does not look like tissue origin at all
What is anaplasia
Lack of differentiation AKA poor differentiated
Can malignant tumours be well differentiated?
Yes - malignancy depends on ability in invade and metastasize
What are the features associated with anaplasia? 4
- Pleomorphism (variation in size and shape of cells)
- Abnormal nuclear morphology eg hyperchromatic nucleus
- Mitosis (atypical blizzard mitotic figure eg tripolar rather than bipolar)
- Loss of polarity eg loss of basement membrane
What is dysplasia
Disorganised, disordered growth, usually epithelial cells. Has similar features with anaplasia eg increased N:C ratio, mitosis…etc
What is carcinoma in situ
Dysplasia severe invades all layers of epithelium, but basement membrane is intact
Why do benign tumours do not apread
Compression from mass > hypoxia of surrounding tissue > increased fibroblast and stromal cells > increased ECM deposits > capsule
Which benign tumour does not develop a capsule
Hemangioma
What is the single most important marker of malignancy
Metastisis
Which infection causes bladder cancer?
Schistomoniasis
Cadmium is linked to which cancer?
Prostate
What cancers is arsenic linked to? 2 Typical occupation associated? 2
Lung and skin carcinoma
Metal smelting, electrical conduction devices, animal dips
What cancer is asbestos linked to? 5 Typical occupation associated? 3
Lung, oesophageal, gastric, colon, mesotheliom
Roofing, construction, flooring
What cancer is benzene linked to? 1 Typical occupation associated? 3
Acute myeloid leukemia
Detergent/Dry cleaning, rubber use, light oil
What cancer is linked to beryllium linked to? Typical occupation associated? 3
Lung carcinoma
Missile fuel, space vehicles, aerospace
Which cancer Vinyl chloride linked to? 1 Typical occupation associated? 2
Hepatic angiosarcoma
Refrigerant, plastics adhesive
What mutation contributes to oncogenesis?
RAS mutation
Which checkpoint in the cell cycle is affected by ionising radiation?
G2/M
What is the most common type of hamartoma?
Lung hamartoma
What chromosome is associated with CML?
Philadelphia T (9:22)
What enzyme activity is abnormal in CML?
Tyrosine Kinase (increased)
What are examples of Tyrosine Kinase inhibitors?
Imatinib
Desatinib
Bosutinib
Cytokeratin found in cancer means —(origin tissue)
Epithelium origin
What is ‘oncogene addiction’?
Tumour Genesis is highly dependent on activity of one oncoprotein
What is the role of p14 in oncogenesis?
Increases p53 levels
What is the role of GAP in oncogenesis?
Inhibits RAS
What is the role of p16 in oncogenesis?
Inhibits RB
What is MYC in oncogenesis?
Upregulates rRNA
upregulate Warburg effect
Upregulate cyclins
What is the role of BRCA normally? 2
Repairs double stranded DNA
Halts cell cycle progression in damaged cells
How does Hepatitis virus cause hepatocellular carcinoma?
Damages hepatocytes, making then constantly regenerate
How do tumour cells cause lymph node metastasis?
Increased laminin receptors on tumour cells
How does HPV cause cervical cancer? 2
- E7 (gene) binds RB protein (inactivate).
- E6 inactivates p53
Which tumour is the NF-1 gene seen in?
Schwanomma
Neurofibroma mechanism?
Persistent activation of Ras gene (loss of NF-1)
Mechanism of phorbol esters causing cancer?
Activates protein kinase C
BRCA-1 vs HER-2 breast cancers (in history)
BRCA-1 has a family history
Patients gets hepatic carcinoma from eating mouldy peanuts. Cause?
Aspergillus flavis: aflatoxin B1
Recurrent skin cancers genetic disorder?
Xeroderma pigmentosum
Inheritance of xeroderma pigmentosum?
Autosomal recessive
Mechanism of cancer in xeroderma pigmentosum?
Unable to repair DNA damage from UV light
What mutation is present in neuroblastoma?
N-myc
T(14:18) follicular lymphoma mutation?
Bcl-2
Metastatic melanoma that run in families, gene mutation?
P16
High levels of cathepsin D in tumour cells suggest (characteristic)
Invasiveness
Alpha fetoprotein is associated with which cancer?
Hepatocellular carcinoma
What quality do tumours that express bcl-2 have?
Lack apoptosis
Tumours that express abl oncogene have which characteristic?
Increased tyrosine kinase
Which oncogene causes reduced ability to hydrolyze GTP?
Ras
High alkaline phosphatase suggests where the Mets is?
Bone
