Flashcards in Classes 6-7 Neoplasms Deck (51):
New growth. Uncontrolled.
Normal cell growth requires
1. Genetic material (DNA or RNA)
2. Signals from one cell to another.
3. Growth inhibiting and growth promoting substances.
Neoplastic cell proliferation is:
Clinical classification of neoplasms
Benign -- limited growth good potential
Malignant -- uncontrolled growth. Poor potential.
Benign vs malignant: Macroscopic features
- sharply demarcated
- often encapsulated
- expansive growth (may lead to atrophy and fibrosis)
- no clear margins
- no encapsulation
- invasive growth.
- hemorrhage and necrosis
Benign vs malignant tumours: microscopic features.
- resembles original tissue
- show high levels of differentiation
- differs from original tissue
- anaplasia (cells take on new tissue)
Benign vs malignant tumours: cellular features
- homogenous cell population
- well developed cytoplasm
- regular nucleus which occupies small portion of the cell
- even distribution of chromatin
- heterogenous cell populations
- nuclei vary in shape and size. Generally large.
- variable cytoplasm.
-hyper chromatic (more chromatin, uneven distributed in prominent nucleoli)
Abnormal number of chromosomes
Characteristic of malignant cells.
Process by which malignant cells move from one site in the body to another.
2. Blood (hematogenous spread)
3. Body cavities.
Probably benign tumour of mesenchyme cells.
Benign tumour of fibroblasts
Benign tumour of cartilage
Benign tumour of adipose tissue
Benign tumour of smooth muscle cells
Benign tumour of bone
Benign tumour of striated muscle.
Benign tumour of epithelial cells. Composed of glands or ducts unless otherwise specified.
Villus or tubular adenomas
Adenoma of GI tract
Also known as polyps.
Benign protuberance of skin, bladder, larynx.
Benign cystic tumours of hollow spaces lined by neoplastic epithelium
Malignant tumour of mesenchymal cells
Malignant tumour from fibroblasts
Malignant tumour of cartilage
Malignant tumour of adipose.
Malignant tumours of epithelial cells
Malignant tumour of glands and ducts
3 malignant "~oma"s
Lymphoma (lymphoid cells)
Glioma (glial cells)
Malignant tumour composed of embryonic cells from embryonic primordia
Neuroblastoma (adrenal medulla or immature neural cells)
Benign tumour derived from germ cells.
Contain tissue derived from ecto, meso and endoderm layers.
Malignant tumour of germ cells.
Based on clinical assessment.
Extent of tumour spread.
Based on size (T), lymph metastases (N), distant metastases (M)
I-IV or A-D.
Better predictive value than grading
Grading of tumours
Grade 1 -- well differentiated
Grade 2 -- moderately well differentiated
Grade 3 -- undifferentiated.
Biochemistry of cancer cells
Requires less O2
Simpler and less abundant RER
Loss of functional capacity
Larger than normal and often with nuclear irregularity.
May regress and assume fetal features.
Ex. Liver cancer cells produce alpha-fetoprotein. Intestinal carcinoma cells produce carinoembryonic antigen.
Where do carcinogens act?
1. Site of contact
2. Site of digestion
3. Site of metabolic activation (liver)
4. Site of excretion (urine)
6 steps of chemical carcinogenesis
1. Ingestion of procarcinogen
2. Initiation -- start of genetic changes in cell
3. Promotion -- initiated cells stimulated to proliferate
4. Conversion -- to new cell type with ability to proliferate on its own
5. Progression -- acquisition of new genetic features.
6. Clonal expansion
1. DNA viruses
2. RNA viruses
A. Acute- or slow- transforming
Become directly integrated into cell's genome.
Epstein Barr Virua
Human herpes DNA virus with predilection for B-cells
May produce infectious mononucleosis
Related to Burkitt's lymphoma (B cell neoplasia) and nasopharyngeal cancer.
Human T cell lymphoma/leukemia virus 1 (HTLV)
Causes rare form of adult T cell leukemia.
Normal cellular genes that can be transformed into oncogenes by four factors:
1. Point mutation
2. Gene amplification
3. Chromosomal rearrangement
4. Insertion of viral genome. (Typical of slow transforming RNA viruses. Also hep B)
Tumour Supressor Genes
Regulatory mechanism that protect against activated or newly acquired oncogenes.
Wasting. May be a symptom of cancer
Consequence of Cancer that isn't a direct effect of cancer. Caused by substances secreted by cancer cells.
May be caused by small cell carcinoma of the lung which also causes adrenal over activity.
Squamous cell carcinoma of lung (or breast cancer) may result in weakening of the bones.
Pathological increase in red blood cells
May be paraneoplastic effect of renal cell carcinoma.
Venous thrombosis can be a paraneoplastic effect of
The number of new cases in a certain population over a specific period.