Cancer 1: Cellular pathology of cancer Flashcards
Define metaplasia
A reversible change in which one adult cell type (usually epithelial)is replaced by another adult cell type
When does metaplasia occur
Adaptive
Give examples of metaplasia
..
Define dysplasia
an abnormal pattern of growth in which some of the cellular and architectural features of malignancy are present
pre-invasive stage with intact basement membrane
Is dyplasia invasive?
pre-invasive stage with intact basement membrane
Outline the cellular features of dysplasia
loss of architectural orientation
loss in uniformity of individual cells
nuclei: hyperchromatic (dark), enlarged (increased nucleo-cytoplasmic ratio)
mitotic figures: abundant, abnormal, in places where not usually found
What are mitotic figures?
….
Examples of dysplasia:
Cervix, bronchus, colon, larynx, stomach and eosophagus
CERVIX - HPV infection BRONCHUS - Smoking COLON - Ulcerative Colitis LARYNX - Smoking STOMACH -Pernicious anaemia (inflammatory process) OESOPHAGUS- Acid reflux
Outline physiological metaplasia
example of physiologic metaplasia is the squamous metaplasia that occurs in the uterine cervix during the menstrual cycle as the squamocolumnar junction migrates across the transformation zone
Outline the cell type change in barrets oesophagus
squamous cell –> columnar in response to pH change
How can smoking cuase squamous cell carncinoma in the lung
metaplasia (columnar–> squamous) due to smoking –> dysplastic
What are the two types of dysplastic
Low grade (low risk of progression, likely to be easily removed)
High grade
Look at which is darker/higher nucleo-cytoplasmic ratio
Define NEOPLASIA, TUMOUR, MALIGNANCY
An abnormal, autonomous proliferation of cells unresponsive to normal growth control mechanisms
Differeniate benign and malignant tumours
do not invade do not metastasise
encapsulated
usually well differentiated
slowly growing
normal mitoses
T/f benign tumours inade locally but not metastatically
F…. do not invade local tissue
What does well differentiated tissue mean
Looks like the tissue it comes from, (i.e. looks like a colon cell) and not looking dysplastic
SO A TUMOUR can be BENIGN (well differentiated… I,e, just a neoplasm with too much growth, but not abnormal growth) or MELIGNANT (too much growth and abnormal growth)
When could a benign tumour be fatal
In a dangerous place: meninges, pituitary
Secretes something dangerous: insulinoma (tumour of beta cell of oancreas)
Gets infected: bladder
Bleeds: stomach
Ruptures: liver adenoma
Torts (twisted): ovarian cyst
LIST RobBeth
Outline a malignant tumour
- invade surrounding tissues
- spread to distant sites
- no capsule
- well to poorly differentiated
- rapidly growing
- abnormal mitoses
Define metastasis
A metastasis is a discontinuous growing colony of tumour cells, at some distance from the primary cancer
How does a tumour metastasise
These depend on the lymphatic and vascular drainage of the primary site
Which type of tissue drainage has the worst prognosis
Lymph node involvement has a worse prognosis
Where do the testicular lymph nodes drain
To the aortic lymph nodes
What is dukes A and dukes C
dukes A= only in gut wall
dukes C= spread to lymph nodes
State the two types of benign epithelial tumours
Of surface epithelium
= PAPILLOMA
Of glandular epithelium = ADENOMA
Give examples of papilloma
skin, bladder
Give examples of adenoma
stomach, thyroid, colon, kidney, pituitary, pancreas
What is a carcinoma
A malignant tumour derived from epithelium
What are the types of carcinomas
squamous cell
adenocarcinoma,
transitional cell (i.e. from bladder)
basal cell carcinoma (skin)
State the types of soft tissue tumours
osteoma, lipoma, leiomyoma, chondroma
What is a sarcoma
A malignant tumour derived from connective tissue (mesenchymal) cells
Outline types of sarcoma
Fat = LipoSARCOMA Bone = OsteoSARCOMA Cartilage = ChondroSARCOMA
What is a rhabdomyosarcoma
Muscle
striated sarcoma
What is a LeiomyoSARCOMA
smooth muscle
What is a sarcoma over the nerve sheath called
Malignant Peripheral Nerve Sheath Tumour
Define leukaemia
a malignant tumour of bone marrow derived cells which circulate in the blood
What is lymphoma
Lymphoma is a malignant tumour of lymphocytes (usually) in lymph nodes
What is a teratoma
A teratoma is a tumour derived from germ cells, which have the potential to develop into tumours of all three germ cell layers
Which type of cell can teratoma differentiate into
ectoderm,
mesoderm,
endoderm
Where are teratoma often found
Ovaries and testes
What are teratomas usually lieke in males and females
Gonadal teratomas in males, all malignant
Gonadal teratomas in females, most are benign
What is a hamartoma
localised overgrowth of cells and tissues native to the organ.
cells are mature but architecturally abnormal
When should hamartoma stop growing
when the child does
Give example of hamartoma
e.g. bile duct hamartomas, bronchial hamartomas,
Give examples of tumours ending in -oma which are malignant
Lymphoma and melanoma
How us the differentiation of atumour assessed
Evidence of normal function still present production of:
keratin (for squamous cell carcinoma)),
mucin (for adenocarcinoma)
bile
hormones
Are there alternative grading sstems or the same for everything
Various grading systems - for Ca breast, prostate, colon
What is a tumour which has no differentation called?
no differentiation, ANAPLASTIC carcinoma
very bad
What is TNM
The Tumour, Node, Metastasis (TNM) system can be applied, and individualised, to tumour in all sites
What is assessed in looking at tumors
The grade of a tumour describes its degree of differentiation
The stage of a tumour describes how far it has spread
T/f stage and grade tend to corespond
Tumours of higher grade (i.e. more poorly differentiated) tend to be of higher stage (i.e. spread further)
Is stage or grade more important for prognosis?
stage is more important than grade
