Tumour Biology Flashcards
What is Cancer ?
An uncontrolled proliferation of cells
How many cells do we have ?
37.2 trillion
How badly your body regenerates?
Every 7 years
What do cells do and what do cancer cells do ?
Cells divide continuously to replace damaged or dead cells. There are control mechanisms to regulate cellular growth rate and differentiation.
In cancer, these mechanisms fail and cells grow without control and without a useful function, leading to unchecked growth that progresses toward limitless expansion
In average how many mutations make a cancer cell ?
Six
Why is cancer potentially dangerous ?
because it can spread through your body
What are the Properties of Beningn Tumour ?
Slow - Growth Rate
Expansion -Character of Growth
Remains Localized - Tumour Spread
Well Differentiated - Cell Differentiated
What are the properties of Malignant Tumour ?
Rapid - Growth Rate
Character of growth - Infiltration
Tumour Spread - Metastasis
Cell Differentiation - Poorly differentiated
how many mutations does it take to make a cancer cell?
6
What is Replaced with what ?
The cells lining the stomach are replaced every five days.
-Cells in the epidermis last about a week.
-Red blood cells live for four months
. -Hepatocytes live for about five months.
- A bone completely remodels itself and replaces all of its cells every ten years or so.
- Cells in the intestinal tract and certain muscles last for about fifteen years.
- Cells that rarely—if ever—turn over: oocytes, cardio myocytes and neurons.
Why do cells continue to divide ?
Cells divide continuously to replace damaged or dead cells.
There are control mechanisms to regulate cellular growth rate and differentiation.
In cancer, these mechanisms fail and cells grow without control and without a useful function, leading to unchecked growth that progresses toward limitless expansion
Examples of Normal Growth : The skin ( The epidermis)
The epidermis is roughly a dozen cells thick, cells in the bottom row of this layer (the basal layer) divide to replenish the cells shed from the surface of the skin
Every division produce a basal cell (to maintain the basal layer) and another cell that loses the capacity to divide and migrates out of the basal layer.
Examples of Cancer growth : The skin ( the epidermis )
During skin cancer, the basal cells divide faster than is needed to replenish the cells being shed from the surface of the skin.
Each time one of these basal cells divides, the two newly formed cells will often retain the capacity to divide
Regardless of the growth rate, tumors ultimately increase in size until the normal organization of the tissue gradually becomes disrupted.
What is Apoptosis ?
Is the death of cells which occurs as a normal and controlled parts of an organism growth or development they are form of programmed cell death .
Which help remove cells during development , eliminating any cancerous or virus infected cells /maintains balance in the body .
What is Malignant ?
They are tumours that may invade its surrounding tissues or spread around the body .
What is Benign ?
The tumour does not invade its surroundings tissues or spread around the body .
Carcinoma ?
Tumour/cancer arising in the epithelial tissue or skin on the lining of the intestinal organs .Including endormal /ectodermal tissue .
What is Lymphoma ?
its cancer which arise of the lymph nodes including leukaemia and hematopoietic stem cells.
What is Sarcoma ?
Malignant tumours made of fat , muscle etc. connective tissues .
What are tumours classified as ?
Adeno- gland
Chondro- Cartilage
Lip-Fat
Myo -muscle
Osteo- bone
What is Neoplasm ?
A type of abnormal and new growth of tissue in a part of the body as a characteristic of cancer .Regardless of their growth rate , tumours ultimately increase in size until the normal organisation of the tissue gradually becomes disrupted .
Invasion and metastasis ?
- Cancer Cells include surrondings tissues and blood vessesls
- Cancer cells are transported by circulatory system to distant sites .
- Cancer cells reinvade and grow at new location .
Benign (not cancer) tumour cells grow only locally and cannot spread by invasion or metasis.
Malignant cancer cells invade neigboruing tissues entering the blood vessles and metablise to different sites .
What does it mean by metasise ?
When they spread from one part of the body to another causing secondary tumours occurs in stage 4
What are the different stages ?
Stage 0 - Carcinoma in sita /Early Form
Stage 1 - Localised
Stage 2 - Early locally advanced
Stage 3 - Late locally advanced
Stage 4 - Metastasised
Why is early detection important as well as what occurs during early detection ?
May minimse a persons risk of dying from cancer .Therefore improving our methods for early detection is currently a high property for cancer researches
Screening methods are designed to check for cancers in peoples with no symtoms such as cervical , breats , prostate , colon and ovarian cancers.
Screening methods
Physical exam and history: to check warning signals and patient’s habits and past illnesses and treatments.
- Laboratory tests: samples of tissue, blood, urine, or other substances in the body.
- Imaging procedures: Procedures that make pictures of areas inside the body.
- Genetic tests: Tests that look for certain gene mutations (changes) that are linked to some types of cancer.
What is Biopsy ?
an examination of tissue removed from a living body to discover the presence, cause, or extent of a disease.
What results do we gather from Biopsy test ?
Hyperplasia
the enlargement of an organ or tissue caused by an increase in the reproduction rate of its cells, often as an initial stage in the development of cancer.
What happens when your results are Dysplasia ?
Abnormal type of excessive cell proliferation characterized by loss of normal tissue arrangement and cell structure.
Often reversible but occasionally malignant.
What happens when your results are Carcinoma in Situ ?
Most severe cases of dysplasia: carcinomas in situ.
dysplasia: carcinomas in situ.
Uncontrolled growth of cells that remains in the original location but may metastasize.
What are the staging of tumour size based on ?
Staging is based on tumor size, invasion of surrounding tissues, and metastasis to lymph nodes or other parts of the body.
