Neoplasia Flashcards
How do you classify neoplasms
- on cell origin
E.g epithelial - on tumour behaviour
E.g malignant
How do you classify tumours
- Epithelial - carcinoma
- Mesenchymal - liposarcoma
- Neuroectoderm - astrocytoma
- Haemopoietic - lymphoma
- Germ cells - teratoma
Benign vs malignant tumour
Cell growth of tumour cell
See abnormal mitosis in malignant cells
Gross description of tumour
Size
Shape
Number
Consistency
Site
Special features
Grading tumours - how it looks
Grade 1 - well differentiated
Grade 2 - moderately differentiated
Grade 3 - poorly differentiated
Tumour morphology
Tumour staging
The extent of the tumour in the body,
How it has spread
What’s does grade 1 squamous cell carcinoma look like
Tumour resembles normal squamous epithelium and contains proportion of differentiated keratinocyte-like squamous cells.
Intercellular bridges are always present.
Keratin pearls are frequently found.
Mitoses are scanty.
What does grade 2 squamous cell carcinoma look like
Tumour cells exhibits more nuclear pleomorphism.
There is usually less keratinisation.
Increased number of mitoses, including abnormal mitoses.
What does grade 3 squamous cell carcinoma look like
Non-keratinsed basal-type cells predominate.
Barely discernible intercellular bridges,
and minimal
keratinisation.
High mitotic rate, including abnormal mitoses.
Effects of benign tumours
- discomfort
- production of active substance, e.g. hormone (thyroid adenoma)
- Pressure effect on adjacent tissue, e.g. intracranial or intrauterine
Direct effects of malignant tumours
• Pain, rapidly growing infiltrative mass
• Blood loss, ulceration, haemorrhage, anaemia
• Mechanical effect, stenosis or obstruction
What are paraneoplastic syndromes
• Paraneoplastic syndromes are symptoms that occur at sites distant
from a tumour or its metastasis.
• Pathogenesis unclear, but symptoms may be secondary to substances
secreted by the tumour or a result of antibodies directed against
tumours that cross-react with other tissue.
• Up to 20% of cancer patients experience paraneoplastic syndromes.
What is tumour grade
biological nature of tumor, based on histological analysis: differentiation, mitotic activity, pleomorphism
What is tumour stage
extent of tumour: size and spread, after pathological and radiological analysis
5 main modes of tumour spread
• Local invasion.
• Lymphatic spread.
• Vascular spread.
• Other ways of spread: Transcoelomic spread or Intraepithelial spread.
What is local invasion
Tumour spread into surrounding tissues by the direct route. Examples: carcinoma of the breast invading overlying skin and
carcinoma of the cervix invading rectum or bladder
What is lymphatic spread
• Cancer spread via lymphatic vessels
draining the site of primary tumour.
• Neoplastic cells are conducted to local
lymph nodes where they may form
secondary tumours, e.g. breast cancer
spreading to axilla lymph nodes, or
tongue cancer spreading to neck
nodes.
• Form the basis of N (lymph node)
What is vascular spread
• Tumour spread via the veins
draining the primary site.
• Gut tumours tend to spread via
the portal vein to the liver.
• In the systemic circulation,
neoplastic cells may be trapped
in the lung to form pulmonary
metastases.
• The basis of M staging (metastasis)
What is Transcoelomic spread
• Tumours can spread across
coelomic spaces, e.g. across the
peritoneal or pleural cavities.
• Carcinoma of the ovary may
spread transcoelomically to
produce large numbers of
metastatic deposits on the
peritoneal surfaces
What is intraepithelial spread
How to use TNM classification to stage tumours
T- tumour
N- node
M- metastasis
Dysplasia is…
Disordered development of epithelium
It may be pre-malignant
What are proto-oncogenes
• Genes commonly used during normal growth and development.
• Usually under-control.
• Without control, they have the potential to produce neoplasms through
their excessive expression.
What are oncogenes
• Genes that have made the transition , i.e. activated proto-oncogenes.
• Capable of producing neoplasms.
• Most oncogenes cause unregulated cell growth through promotion of cellular division, which results in further mutations.
Conversion of proto-oncogene to oncogene
• Overexpression of the gene.
• Amplification of the gene.
• Point mutation in the gene.
• Translocation of the gene to another region with resultant
overexpression of the gene, or resultant production of protein with
oncogenic activity.
What are genes p53 and rb1 does
They are tumour suppressor genes
What does nitric oxide do to vessels
Causes vasodilation
What mediator causes b cells to plasma cells
IL-6
