Cancer Definitions and Nomenclature Flashcards
Learn the terms relating to cancer jargon.
Define the term “metaplasia”.
An adaptive and reversible change in which one adult cell type (usually epithelial) is replaced by another adult cell type.
Give one example of metaplasia as a) a physiological response and b) a pathological response.
a) Cervical changes in the female during puberty.
b) Barrett’s oesophagus in response to continued presence of acid in the oesophagus.
Define the term “dysplasia”.
An abnormal pattern of growth in which some of the cellular and architectural features of malignancy are present
The pre-invasive stage presents with intact basement membrane.
Define the term “neoplasm”.
An abnormal, autonomous proliferation of cells unresponsive to normal growth control mechanisms.
What features differentiate benign tumours from malignant ones?
- Do no invade or metastasise
- They are encapsulated
- They are usually well-differentiated
- They are slow-growing
- They usually have normal mitoses
List the main features of dysplasia.
Loss of architectural orientation
Loss in uniformity of individual cells
Hyperchromatic, enlarged nuclei
Mitotic figures: abundant, abnormal, in places where not usually found
Where is dysplasia commonly found?
Cervix - HPV infection Bronchi - Smoking Colon - UC Larynx - Smoking Stomach - Pernicious anaemia Oesophagus - Acid reflux
What are the key features of malignant tumours?
- They invade surrounding tissues
- They spread to distant sites (metastasis)
- They are not encapsulated
- They are well to poorly differentiated
- They are rapidly growing
- They show abnormal mitoses
What is a metastasis?
Discontinuous growing colony of tumour cells, at some distance from the primary cancer.
Which factors determine the locations of metastases?
Lymphatic and vascular drainage of primary site.
Lymph node involvement has a worse prognosis.
Benign epithelial tumours
Of surface epithelium = Papilloma
–> E.g skin, bladder
Of glandular epithelium = Adenoma
–> E.g stomach, thyroid, colon, kidney, pituitary, pancreas
What is a carcinoma?
Malignant tumour derived from epithelium.
Squamous cell
Adenocarcinoma,
Transitional cell
Basal cell carcinoma
What is an osteoma?
A benign soft tissue tumour.
What is a sarcoma?
A malignant tumour derived from connective tissue (mesenchymal) cells.
Fat = LipoSARCOMA Bone = OsteoSARCOMA Cartilage = ChondroSARCOMA Muscle --> Striated = RhabdomyoSARCOMA, --> Smooth = LeiomyoSARCOMA Nerve sheath = Malignant Peripheral Nerve Sheath Tumour
What is lymphoma?
A malignant tumour of lymphocytes (usually) in lymph nodes
What is leukaemia?
A malignant tumour of bone marrow derived cells which circulate in the blood.
What is a teratoma?
A tumour derived from germ cells, which have the potential to develop into tumours of all three germ cell layers (ectoderm, mesoderm, endoderm)
What is a hamartoma?
A localised overgrowth of cells and tissues native to the organ.
The cells are mature (cytologically normal) but architecturally abnormal.
It is common in children, and should stop growing when they do.
Examples: bile duct hamartomas, bronchial hamartomas
What is lymphoma?
A malignant tumour of lymphocytes (usually) in lymph nodes
What is leukaemia?
A malignant tumour of bone marrow derived cells which circulate in the blood.
Explain what “grade” and “stage” mean in reference to tumours.
The grade of a tumour describes its degree of differentiation.
The stage of a tumour describes how far it has spread.
Tumours of higher grade (i.e. more poorly differentiated) tend to be of higher stage (i.e. spread further), but stage is more important than grade in determining prognosis.
What criteria are used to assess the differentiation of a malignant tumour?
- Evidence of normal function still present (e.g production of keratin, mucin, bile, hormones)
- Various grading systems - for Ca breast, prostate, colon
- No differentiation –> ANAPLASTIC carcinoma
What is the TNM system?
The Tumour, Node, Metastasis (TNM) system can be applied, and individualised, to tumour in all sites.
Explain what “grade” and “stage” mean in reference to tumours.
The grade of a tumour describes its degree of differentiation.
The stage of a tumour describes how far it has spread.
