Cancer Flashcards
What are 4 Risk Factors and Underlying Causes for the Development of Cancer?
- Age
- Genetics
- Environmental Exposures
- Infection
Risk Factors and Underlying Causes for the Development of Cancer
What is the relationshipship between age and cancer?
- As age increases, the risk of mortality increases
- As you grow older, more likely to be exposed to mutations. The healing process slows and repair processes weaken
- Different age ranges have different risks of cancer
Risk Factors and Underlying Causes for the Development of Cancer
What are the relationships between environmental factors and cancer?
- Smoking
- 30% of all cancer deaths in developed countries are caused by smoking
- Lung cancer most common
- Alcohol
Risk Factors and Underlying Causes for the Development of Cancer
What are the relationships between Infections and cancer?
- Viruses associated with development of specific cancers
- Recurrent infections. Reach a stage where body gets tired. Cancer results.
- Papillomavirus
- Epstein-Barr Virus
- HIV
- Hep B and C
- H. Pylori
What is the Aim of Cancer Screening?
- Aim to detect disease in asymptomatic individuals at an early stage and treat as early as possible and be least invasive to patient
- Screening for breast, colon and cervical cancer is beneficial for certain age groups
When is a Diagnosis made for Cancer?
What does Final Diagnosis rely on?
Size of tumour?
- Diagnosis made following screening, development of symptoms or incidental findings
- Final diagnosis relies on an invasive tissue biopsy
- Size of tumour and presence of cancer in lymph nodes suggests disease spread – important prognostic marker(s)
Describe how the extent of Disease is defined
- Defining the extent of disease is the first priority after the diagnosis is made
- Staging is a series of invasive and non-invasive tests
- Clinical Staging
- Pathologic Staging
In Staging, the Information used to define the disease is as what?
- This information is used to define the disease as:
- Localised (limited stage) or metastatic (advanced)
- Goals of treatment for localised and metastatic disease are very different
What’s the most common system to Stage Disease?
- Most common system is the TNM (Tumour, Nodes, Metastasis) system
- T – Size of the Primary Tumour (T1 – T4)
- N – Presence and Degree of Nodal Involvement (N0 – N4)
- M – Presence or Absence of Metastatic Disease (M0 – M1)
What are the Goals of Cancer Treatment?
- Cure – generally for localised cancers (short, strong therapy)
- Extend life expectancy and enhance quality of life – generally for metastatic cancers (not short or strong – about the comfort of the patient and extending their life)
What is the Role of Adjuvant Therapy in Typical Cancer Treatment?
What are examples of this?
- Given in association with primary treatment (usually surgery or radiotherapy)
- Aim of increasing the cure rate by ablating any residual (undetected) microscopic tumour mass
- Examples
- Chemotherapy to shrink tumour, followed by surgery to remove the tumour
- Chemotherapy may also be given following the surgery
What are the Specific Use of Surgery in Cancer Treatment?
- Most effective cure (up to 40% can be cured with surgery alone but depends on location)
- Few metastatic lesions can be removed that will result in cure of a patient with cancer
What are the Specific Use of Radiotherapy in Cancer Treatment?
Is it used alone?
Side effects are?
What type of cancers can be cured with Radiotherapy?
- Physical form of therapy that destroy any tissue in its path
- Can be used alone or in combination to cure localised tumours and to control the primary site of disease
- Side effects are generally localised
- Breast, Hodgkin’s Disease, Head and Neck, Prostate and Gynaecological cancers can be cured
Can Chemotherapy cure tumours?
What are the types of Chemotherapy?
- Most solid tumours cannot be cured with chemotherapy alone
- Types:
- Cytotoxic e.g. methotrexate, fluorouracil, doxorubicin
- Toxic to all cells
- Hormonal
- Tumours use hormones as growth factors
- Targeted
- Antibodies (monoclonal) or small molecules
- Target genetic lesions specific to the cancer cells (e.g. imatinib, traztuzumab)
- Cytotoxic e.g. methotrexate, fluorouracil, doxorubicin
Combination Therapy is effective because it accomplishes 4 important goals not possible with single agent therapy. What are these 4 goals?
- Provide maximum cell kill within the range of toxicity tolerated by the host for each drug
- Provide a broader range of coverage (different mechanisms) of any resistant cell lines in the heterogenous tumour population
- Prevent or slow the development of new resistant lines
- Synergism
What are the Challenges of Combination Therapy?
- Multiple toxicities with greater patient discomfort
- Impact of dose effect
- Complicated to administer
- Expensive
What is the Importance of Dose in Chemotherapy Protocol Development?
- Ideally: efficacious dose without toxicity
- Dose-response curve for almost all anti-tumour agents is steep for therapeutic and toxic effects
- Reducing the dose slightly can cause a reduction in therapeutic effectiveness – take care, otherwise favouring tumour to grow
What is the Importance of Frequency in Chemotherapy Protocol Development?
- Ideally, continue treatment for maximum cell kill, but don’t want break for too long to allow tumour to regrow – caution for toxicity
- A reduction in dose rate of therapy made a greater than 2-fold difference in complete remission rates
What happens to the Immune System when someone develops cancer?
- Body’s immune system recognises and eliminates abnormal and malignant tumour cells from the body
- Equilibrium between tumour cells and immune system can shift in favour of the tumour and leads to an immune response below the threshold required for tumour elimination and emergence of tumour cells
