Week 4 lec - cancer Flashcards
What is the most prevalent cancer in males?
prostate
what is the second most common cancer among males and females?
colorectal
what is the most common cancer among women?
titty
how many new cancer cases are detected each year world wide?
14 million
how many people die from cancer each year world wide?
8.2 million
what is neoplasia?
Literally means new growth. It is an excessive proliferation that occurs independently of physiologic growth-regulatory stimuli
Three key characteristics of neoplastic growth
- Unregulated by normal physiological mechanisms
- Irreversible
- Monoclonal–arises from a single abnormal cell
A neoplasm is colloquially called a ______
tumour
Is this hyperplasia or neoplasia?
Growth is regulated normally, growth is reversible, can originate in a single cell (monoclonal) or multiple cells
hyperplasia
Is this hyperplasia or neoplasia?
Growth is not regulated by normal physiological mechanisms, growth is not reversible by normal physiological mechanisms, originates in a single cell (monoclonal)
neoplasia
what is the main difference between hyperplasia and neoplasia?
hyperplasia involves a normal (non mutated cell), whereas neoplasia involves a mutated cell
Well-differentiated tumour cells?
bear a close resemblance to the tissue of origin
Poorly differentiated tumour cells?
minimal resemblance to the tissue of origin
Anaplastic tumour cells
(literally ‘backward formation’) = undifferentiated (very poorly differentiated) – no resemblance to tissue of origin
what would you prefer to have, a well-differentiated or poorly differentiated tumour?
The progosis is better for well-differentiated - they are less aggressive and closer to the tissue from where they originated. The drawback is they tend to be a bit harder to treat because of the slower growth rate.
what is the parenchyma?
The proliferating cells of a tumour
what is the supportive stroma?
Connective tissue and blood vessels surrounding tumour, provides the framework on which the parenchymal cells grow
describe a benign tumour
- Margins of the tumour well defined
- Does not invade surrounding tissue or spread distantly
- Generally has a good prognosis, and death is unusual
describe a malignant tumour
- Margins are poorly defined (locally invasive)
- Neoplastic cells destroy surrounding tissue, and spread distantly (metastasize)
- Generally has a poor prognosis
are benign tumours well or poorly differentiated?
well differentiated
do benign tumours have major abnormalities in growth regulation?
no
can benign tumours be fatal?
yes
how can a benign tumour be harmful?
- Compression of adjacent structures (e.g. meningioma)
- Endocrine tumours can secrete hormones (e.g. pituitary adenomas)
are malignant tumours well or poorly differentiated?
can be either
what does metastatize mean?
to spread distantly
what are the 4 mechanisms by which malignant neoplasms can spread? (metastasis)
- *1. Direct invasion** - may invade directly into adjacent organs, or through nerves
- *2. Spread by lymphatics** - to lymph nodes
- *3. Haematogenous spread** (by blood) - to distant sites (common sites
- *4. Transceolomic spread** – abdominal cavity tumours spread directly across peritoneal spaces by seeding of cells that migrate to the surfaces of other organs (technically not considered metastasis)
in metastasis, the tumour deposit is discontinuous with the primary tumour excluding what type of spread?
transcoelomic spread
what are the most typical types of metastasis?
haematogenous or lymphatic spread
what is the risk of basal cell metastasis following melanoma?
<0.1%
A categorically malignant tumour is a tumour that has all three malignant qualities of a cancer. What are they?
- Unlimited and uncontrolled growth
- Invasion of surrounding tissue (direct invasion)
- Potential for distant spread (metastasis)
what would a tumor with one or two malignant qualities be regarded as?
could be classed as benign or malignant - often there is disagreement
is breast fibroadenoma benign or malignant?
benign
is breast carcinoma benign or malignant?
malignant
is colonic polyp (tubular adenoma) benign or malignant?
benign.
event though it has uncontrolled growth and invades surrounding tissue, it does not have metastatic potential.
what is fibroma?
benign neoplasm of fibroblasts
what is adenoma?
benign neoplasm of glands
what is lipoma?
benign neoplasm of adipocytes or lipocytes
what is adenocarcinoma?
malignant epithelial tumour of the glands
what is fibrosarcoma?
malignant mesenchymal (connective tissue, fat, muscle, vessels) lesions of fibroblasts
what is liposarcoma?
malignant mesenchymal (connective tissue, fat, muscle, vessels) lesions of lipocytes