Neoplasia 3 Flashcards
(54 cards)
List the 4 carcinomas accounting for over half of all new cancers in the UK
Breast, Lung, Bowel, Prostrate
What percentage of malignant neoplasms are diagnosed in people over 65? Under 24?
Over 65 = 60%
Under 24 = 1%
What are the most common cancers in children under 14?
Leukaemias, central nervous system tumours and lymphomas
Despite a low incidence in the UK, pancreatic cancer accounts for a large percentage of deaths in cancer patients, explain why?
Pancreatic cancer has a very poor 5 year survival rate so despite a low incidence, the majority of patients diagnosed with the disease results in mortality
List the cancers with the best and worst five year survival rates
Best- Testicular, melanoma and breast
Worst- Pancreatic, lung and oesophageal
Which factors must be considered when predicting the outcome of cancer?
- Age
- general health status
- tumour type
- the grade (differentiation)
- tumour stage
- availability of effective treatments
What is tumour stage?
Measure of the malignant neoplasm’s overall burden
How is tumour stage measured?
Most common method is the TNM staging system
T- refers to the size of the primary tumour (T1-T4)
N- describes the extent of the regional node metastasis e.g. N0- N3
M- denotes the extent of the metastatic spread e.g. M0- M1
The T, N and M are then converted into a stage I to IV
Describe the T1 to T4 stages from the TNM classification for breast cancer
T1= less than 2 cm T2= 2cm-5cm T3= greater than 5cm T4= local spread
What is the special system for Lymphoma staging?
Ann Arbor staging
I= single node region
II= indicates two separate regions on same side of diaphragm
III= indicates spread to both sides of diaphragm
IV= indicates diffuse or disseminated involvement of one or more extra-lymphatic organs
What special system is used for colorectal carcinoma?
Dukes staging
Which grading system is used for breast carcinoma and what does the system assess?
Bloom-Richardson
Assesses tubule formation, nuclear variation and number of mitoses
How does grading differ from staging?
Grading measures the level of differentiation whereas staging measures the amount of tumour present
What are the main forms of cancer treatment?
Surgery, radiotherapy, chemotherapy, hormone therapy, treatment targeted to specific molecular alterations
What is adjuvant treatment?
Given after surgical removal of a primary tumour to eliminate subclinical disease
What is neoadjuvant treatment?
Treatment given to reduce the size of a primary tumour before surgical excision
How does radiotherapy kill cells?
- Kills rapidly dividing cells especially in G2 of cell cycle
- High dosage causes either direct or free radical induced damage to DNA which is detected by cell cycle check points and so triggers apoptosis to occur
- Double-stranded DNA breakages also produced damaged chromosomes that prevent M phase in mitosis
What are the different classes of chemotherapy drugs?
- Antimetabolites
- Alkylating and platinum-based drugs
- Antibiotics
- Plant Derived drugs
How do antimetabolites work?
Mimic normal substrates involved in DNA replication
How do alkylating and platinum-based drugs work?
Cross-link the two strands of the DNA helix
How do antibiotics work?
Act in several different ways
For example doxorubicin inhibits DNA topoisomerase needed for DNA synthesis whereas bleomycin causes double-stranded DNA breaks
How do plant derived drugs work?
Block microtubule assembly and interfere with mitotic spindle formation
Give an example of hormone therapy treatment and how it works
Selective oestrogen receptor modulators (SERMs) e.g. tamoxifen bind to oestrogen receptors and prevent oestrogen binding
Used to treat hormone receptor-positive breast cancer
What are tumour markers?
Various substances that are released into the circulation by cancer cells that allow for monitoring of cancer burden
Examples include: hormones, oncofetal antigens, specific proteins and mucins/glycoproteins
