Lecture 1 - Cancer Def., Biology, Screening & Treatments Flashcards
(69 cards)
Cancer in Australia: what are the 5 mot common cancers?
Prostate Colorectal (bowel) Breast Melanoma Lung
These account for more than 60% of all cancers.
What is the breast cancer incident rate?
Prostate cancer incidence rate?
Australia has the highest incidence rate (3rd globally)
Australia has the HIGHEST incidence rate world wide
What are the 3 main Cancers more common in younger individuals (<20 y.o.)?
- Brain cancer
- Leukaemia/lymphoma
- Other neoplasms
What are the 4 main Cancers more common in older individuals (>20 y.o.)?
- Lung
- Colorectal
- Breast
- Prostate
Australian Cancer Statistics:
Increased incidence rates?
Decreased mortality rates?
Incidence rate = Aus has the largest increase in cancer indented over the past decade (>20%)
Could be due to better ability to detect and diagnose.
Mortality rate= decreasing mortality rate, due to effective treatments, and on-going management of patients. (Includes the use of exercise and allied health).
What is Cancer?
It defines a group of diseases.
Some of the body’s cells become abnormal and divide without control as a result of changes (mutations) in the generic information of a cell.
If these abnormal cells grow into a lump (mass), it forms what is known as a tumour.
Tumours can be benign or malignant.
Definition of Normal Cell Division:
Normal cell division= 2 daughter cells being produced, cell growth and old cell death.
Apoptosis= self destruction of a cell through programmed cell death (normal cell death)
Initiation of a tumour:
A tumour is initiated when mutation of a cells DNA occurs, affecting the normal growth and division process.
Cell death DOES NOT occur which results in an increased number of dividing cells.
This process leads to a tumour.
Process of Mutation: 3 damaging agents.
Changes in cell DNA (genes) may be caused by mistakes during cell division or exposure to damaging agents in the environment.
- PHYSICAL = Exposure to ultraviolet and ionising radiation
- CHEMICAL= Exposure to asbestos or tobacco
- BIOLOGICAL= Infection (viral, bacteria, parasite)
What is the PROGRESSION of a tumour?
For the tumour to grow bigger, it must grow its own blood vessels. This is known as ANGIOGENESIS
As the tumour grows it starts to invade neighbouring tissues (Invasion)
Sometimes the cells move away from the primary cancer site, via the blood and lymph, and invade other parts of the body. When the cells reach a new site, it grows to form another tumour, this is called METASTASIS.
What are the two types of tumours?
- Benign= non-cancerous tumour. Cells do not spread to other parts of the body.
- Malignant= cancerous tumour. Cells are able to spread to other parts of the body.
Define Metastasis & name characteristics of it:
Cancer cells that have spread from the original growth site to one or more parts of the body, also known as SECONDARY SITES.
It's the development of secondary malignant tumours Originating from primary tumour Located anatomically distant All cancers have the potential to spread Occurs when cells detach from primary tumour Enter circulation or lymphatic Adhere to new tissue - proliferate Lungs most common site for secondaries
Cancer Biology: How are cancers named?
Each cancer is named after the location of its origin
Metastic cancer is a “secondary version” of a “primary cancer” [Prostate cancer which has spread to nodes, organs, or bone is ‘metastic prostate cancer’ or ‘secondary prostate carcinoma’]
Characteristics of a Benign Tumour?
Slow growing Can be quite large Well organised and differentiated Less destructive Can damage adjacent tissues and cause NECROSIS Rarely cause death
Characteristics of a Malignant Tumour?
Cancer cells form malignant neoplasm Highly unorganised Diverse abnormalities Increased invasiveness - metastasis Decreased drug sensitivity Programmed for proliferation Invade normal tissue Intrinsic ability to kill host tissue
Tumour Biology: define the 2 types of solid tumours?
- Carcinoma= originates in skin or epithelial cells of organs [e.g breast, prostate]
- Sarcoma = originates in connective or supporting tissues [e.g. Bone, cartilage, and muscle]
Tumour Biology: define the 3 Haematological (blood) tumours:
- Lymphoma = cancer of the lymph nodes and lymphatic system [e.g. Non-Hodgkin’s lymphoma, Hodgkin Lymphoma]
- Leukaemia = cancer affecting blood, originates in bone marrow. [e.g. Lymphoblastic leukaemia, Myeloid Leukaemia]
- Myeloma - cancer of plasma cells (mature lymphocytes). [e.g. Multiple myeloma, smouldering myeloma.]
Define a Carcinoma:
Solid tumour
Develop in epithelial cells [tissue linings]
Mostly in organs that secrete substances [e.g. Lung, breast, pancreas, kidney, stomach]
85-90% of all cancers are carcinomas
Define Melonamas:
‘Skin cancer’
Cancerous growths of melanocytes
Most common in skin but also back of eye, mouth, vagina, anus.
Define Sarcomas:
Solid tumours
Originates in connective tissue - bone, muscle, cartilage, fat.
Rarest form of cancer accounting for less than 2%
Define Leukaemia:
Cancer of blood forming organs
Result of abnormal white blood cells
2% of all cancers
Invades vital organs such as liver, lungs, heart, brain - organ dysfunction.
Define Lymphomas:
Malignant cancers of lymphocytes
Originate in lymphatic system
5% of all cancer cases
Hodgkin’ - progress in order from lymph node group to next
Non-Hodgkin’ - widespread within lymph system.
Define a Cancer Patient:
A person who has been diagnosed/receiving treatment.
Define a Cancer Survivor:
A person who, is living with cancer, from the time of diagnosis, through all disease stages, until death.