18 Characteristics of tumours Flashcards
Define cancer:
Uncontrolled growth of cells which invade and spread to distant sites of the body.
Define tumour/neoplasia:
Lesion resulting from autonomous growth of cells that persists in the absence of an initiating stimulus.
Define histogenesis:
The differentiation of cells into specialised tissue and organs during growth from undifferentiated cells.
From most to least, which cancers are most common in men? (3).
Prostate.
Lung.
Colon and rectum.
From most to least, which cancers are most common in women? (3).
Breast.
Lung.
Colon and rectum.
From most to least, which cancers are most fatal in women? (3).
Lung.
Breast.
Colon and rectum.
From most to least, which cancers are most fatal in men? (3).
Lung.
Prostate.
Colon and rectum.
How are tumours characterised? (4).
Differentiation.
Rate of growth.
Local invasion.
Metastasis.
Define differentiation.
The extent t neoplastic cells resemble the normal parenchymal cells, morphologically and functionally.
Define anaplasia:
Neoplasm that consists of poorly differentiated cells - hallmark of malignancy.
What morphological changes are seen in malignancy? (4).
Pleomorphism.
Abnormal nuclear morphology.
Mitoses.
Loss of polarity.
Define pleomorphism:
Variation in size and shape.
Give examples of abnormal nuclear morphology: (5).
High nucleus:cytoplasm ration. Variability in nuclear shape. Chromatin distribution: clumped/lining outside. Hyperchromatism. Large nucleoli.
Name three atypical mitotic figures seen in malignancy.
Tripolar.
Quadripolar.
Multipolar spindles.
What does the grade of a tumour measure?
Level of differentiation.
Well diff = low grade.
Name four hormones produced by bronchogenic carcinoma:
Corticotrophin.
Parathyroid-like hormone.
Insulin.
Glucagon.
Why can benign tumours not invade to neighbouring tissue?
Encapsulated by fibrous tissue.
Rim of extracellular matrix deposited by stroll cells in response to hypoxia from tissue pressure.
What is pseudo encapsulation?
Malignant tumours that look encapsulated. Microscopic exam shows infiltration.
Define metasasis:
Spread of tumour to sites physically discontinuous with primary tumour.
What is metastasis generally correlated with? (4).
Lack of differentiation.
Local invasion.
Rapid growth.
Large size.
Define direct seeding:
Tumour penetrates natural open field.
What is the most common way for tumours to spread?
Via lymphatic system.
What is the pattern of breast carcinoma spread?
Presents in upper outer quadrant.
Disseminates to axillary, then infraclavicular, then supraclavicular lymph nodes.
Define sentinel node:
The first node in a regional lymphatic basin that receives lymph flow from the primary tumour.
Why does cancer cause reactive change in sentinel lymph nodes?
Drainage of tumour cell debris and tumour antigens.
What is haematogenous spread typically seen in?
Sarcomas (also seen in carcinoma).
Define stroma:
Connective tissue network that neoplastic cells are embedded in.
What is a desmoplastic reaction?
Tumour cell derived growth factors induce connective tissue fibroblast proliferation. Causes formation of fibrous stroma.
What are the local complications of a tumour?
Compression.
Destruction due to invasion.
What are the metabolic complications of tumours? (5).
Cachexia. Warburg effect. Neuropathies. Myopathies. Venous thrombosis.
What is cachexia and why does it occur in cancer?
Profound weight loss despite seemingly adequate nutrition.
Tumour derived humour effects that affect protein metabolism.
What is the Warburg effect?
Clinical usage?
Tumours produced high rate of energy by glycolysis and fermentation of lactic acid.
Used in PET scans with FDG uptake.
