Cancer Flashcards
Cancer is…
A group of diseases characterised by the uncontrolled growth and spread of abnormal cells. There are over 200
different types of cancer (in this module, you will look at 5 different types). In the UK, 1 in 2 people will develop
cancer, however, current research and treatment means many cancers can be cured. Some cancers can return and
some cannot be cured, but treatment is often available to control these for some years
Cancer Develops…
when there are gene changes within a cell (or few), which begin to grow and multiply abnormally. This can lead to a
growth of a tumour. This would be known as a primary tumour, and if this spreads (metastasis) around the body, can
develop a secondary tumour. Most cancers occur due to changes within the genes over a person’s lifetime, where
others can begin due to an inherited abnormal gene
• Genes within the DNA would normally grow and reproduce in a controlled and orderly manner, however, sometimes changes occur in the genes, known as mutations, leading to a damaged, lost or copied gene. These changes can happen by chance when cells divide, or can occur due to other factors
• Environmental exposure, such as chemicals in tobacco smoke and exposure to UV can cause mutations and increase risk of cancer development
• Inheriting certain genes such as the BRCA gene can also increase risk of developing cancer.
Development of Cancer
Initiation: Genetic mutations or alterations occur in the DNA of normal cells, leading to the initiation of cancerous changes.
Promotion: Promoters such as lifestyle factors (smoking, diet), environmental exposures (radiation, chemicals), and hormones stimulate the growth of initiated cells.
Progression: Accumulation of additional genetic changes results in the transformation of benign tumours into malignant tumours and the spread of cancer cells to distant sites.
Initiation in Cancer Devlopment
Initiation is the initial step in carcinogenesis (the formation of cancer) where genetic mutations or alterations occur in
normal cells, leading to the initiation of the cancerous process.
Causes of Initiation:
• Genetic Mutations
• Epigenetic Changes.
Types of Initiated Cells:
• Initiated Cells
• Preneoplastic Lesions
Recognition and Repair Mechanisms: cells have various mechanisms to recognise and repair DNA damage caused
by endogenous and exogenous factors. However, if the damage is severe or if repair mechanisms are impaired,
mutations may persist and contribute to the initiation of cancer.
Promotion in Cancer Development
Promotion is the second stage in the process of carcinogenesis. It involves the stimulation of intiated cells to
proliferate and progress towards becoming malignant tumours
Role of Promoters
• Lifestyle Factors
• Environmental Exposure
• Hormonal Factors.
Mechanisms of Promotion
• Cell Proliferation
• Genetic Instability
• Angiogenesis.
Durations and Reversibility: Promotion is often a prolonged and reversible process. Continued exposure to
promoters sustains the growth and progression of initiated cells towards malignancy. However, removing or
reducing exposure to promoters (e.g. lifestyle modifications, environmental interventions) can halt or reverse the
promotion of cancer development, especially in the early stages
Progression in Cancer Devlopment
Progression is the stage in carcinogenesis where intiated or preneoplastic cells acquire additional genetic alterations
and phenotypic changes, leading to the development of malignant tumours and the spread of cancer
Key Events in Progression
• Genomic Instability
• Clonal Expansion
• Invasion and Metastasis.
Preneoplastic: refers to conditions or lesions which precede the formation of benign or malignant tumour (neoplasm)
Microenvironmental Factors: The tumour microenvironment, comprising immune cells, stromal cells, blood
vessels, and extracellular matrix components, plays a crucial role in cancer progression by promoting tumour
growth, angiogenesis, immune evasion, and metastasis
Cancer Stages and Grading
Assigning a stage and grade to a cancer can help provide information on how quickly a cancer is likely to develop and
what treatment protocals may work best.
Stage
How big the cancer is and whether it has spread.
• Can help with deciding which treatment to undergo.
• There are two main types of staging: TNM and the
number system.
TNM = Tumour, Node, Metastasis.
Number system = Stage 1-4.
Grade
How abnormal the cells have become.
• Grade 1-3
• Sometime Grade GX is used, meaning the grade is
undetermined.
Impact of Cancer
• Physical Impact Symptoms vary depending on the type and location of the cancer but may include pain, fatigue, weight
loss, and organ dysfunction.
• Emotional and Psychological Impact Fear, anxiety, depression and uncertainty are common emotional responses to a cancer diagnosis, affecting patients and their loved ones.
• Social and Economic Impact Cancer can disrupt daily life, work and relationships, leading to financial burden and social isolation
Tumour Suppressor Genes (TSG)
TSG play critical role in regulating cell growth, preventing tumour formation and maintaining genomic
stability. TSG encode proteins that help control progression of cell cycle, DNA repair, and apoptosis,
safeguarding against cancer development by inhibiting abnormal cell proliferation and promoting elimination
of damaged cells. Mutations or loss of function in TSG can disrupt these regulatory mechanisms, allowing
cells to grow and divide uncontrollably, leading to tumour formation.
Oncogenes
genes which have the potential to cause cancer when mutated or activated. Typically, they are altered proto- oncogenes, which usually regulate cell growth, differentiation, apoptosis and survival. When proto-oncogenes mutate and change into a oncogene, the cell divides and multiplies uncontrollably
Cell Cycle and Cancer
• Breast Cancer - BRCA1
• Thyroid Cancer - BRAF
• Acute Myeloid Leukaemia - FLT3
• Non-Hodkin’s Lymphoma - p53
• Testicular Cancer - KIT
Surgery
• Cancer surgery is where tissue is removed from the body and is one of the main treatments for cancer. It can be
used to diagnose cancer, stage and treat cancer (on its own or with other treatments) and reduce risk of getting a
particular type of cancer (such as breast removal for those with high risk of breast cancer). Surgery can also be
used to reconstruct a part of the body (such as the breast after a mastectomy)
• Surgery is not suitable for all types of cancer or situations, and depends on the cancer type, size, spread and
location of cancer, and the patient’s general health
• It would not be suitable for cancers of the blood system (leukaemia) or lymphatic system (lymphoma), due to the
cancers being spread throughout the body and surgery not being able to eliminate all of the cancer. If the cancer
is near delicate tissue or vital body parts (such as major blood vessels), surgeons may not be able to remove all of
the cancer, and if the cancer has spread, then surgery may not be the best treatment
• Surgery can help control symptoms or extend life of patients with advanced cancer, even if the cancer cannot be
completely removed or cured with other treatments
• Surgery could be performed to help with treatment, for example having a central line placed in the body, to help
with medication delivery
• Surgery can be performed by open surgery, laparoscopic (keyhole), robotic and endoscopic surgery.
Chemotherapy
• A systemic form of cancer treatment that uses cytotoxic drugs (toxic to cells) that inhibit mitosis or DNA repair
• Cancer cells divide more rapidly than normal cells, therefore the chemotherapy can be selective towards these cells.
However, there are some normal cells that also divide rapidly that can be affected, such as bone marrow and hair
follicles which can lead to side effects such as hair loss
• Chemotherapy usually follows on from surgery (if this is an option), to destroy any remaining cancer cells
• Whether chemotherapy is a suitable treatment would depend on the type of cancer, what the cancer cells look like
under the microscope, whether the cancer has spread and the general health of the patient
• There are over 100 different chemotherapy drugs currently available, with new ones being developed all the time
• Chemotherapy drugs can be used as a single therapy or as a combination of chemotherapy drugs. It can also be
combined with other treatments, such as surgery, radiotherapy, immunotherapy
• Chemotherapy can be administered either by an injection through the vein, intravenous infusion, tablets or capsules
• Chemotherapy might affect fertility of the patient, therefore looking into fertility treatments or support may
benefit patients wanting to have children. Patients should not become pregnant or get someone pregnant whilst
undergoing chemotherapy as some drugs can damage the developing baby. If patients are pregnant at time of
diagnosis, treatment options would be discussed with the health professionals
Radiotherapy
• A form of cancer treatment that uses High-energy radiation to destroy cancer cells
• Usually involves aiming a beam of radiation at the tumour, and can also involve delivery of radioactive materials to the
site of the tumour. This can be delivered by internal (brachytherapy) or external radiotherapy
• Radiotherapy usually follows on from surgery (if this is an option), to destroy any remaining cancer cells
• Treatment usually lasts between 1 to 7 weeks, with most patients having daily treatment Monday to Friday with a rest at weekends
• Side effects may depend on location and type of radiotherapy, with tiredness and skin reactions being more common
• Radioactive iodine treatment is a type of internal radiotherapy which can be used to kill cancer cells in the thyroid
Hormone Therapy
• Can be used to treat tumours that are stimulated to grow by oestrogen or progesterone. It does not work for all cancers
• Hormone therapy blocks or lowers the amount of hormones in the body to stop or slow down the growth of cancer
• More commonly used in cancers such as breast, prostate and endometrial cancer
• Example hormone therapy:
-Breast – Tamoxifen, Aromatase Inhibitors (e.g. Arimidex), LHRH agonists or LH blockers (e.g. Zoladex),
Fulvestrant, chemoprevention
-Prostate - LHRH agonists or LH blockers (e.g. Zoladex), Anti androgens (e.g. Casodex), GnRH blocker (e.g.
Firmagon)
-Endometrial – Progesterone treatment such as medroxyprogesterone acetate and megestrol
Monoclonal Antibody Therapy (mABs)
• A type of targeted therapy
• Works by blocking signals telling cancer cells to divide and grow, and preventing cancer cells developing blood supply. It can also block proteins that help cancer cells evade the immune system
• mABs can also carry cancer drugs or radiation to cancer cells, and can bring together cancer and immune cells to help the immune system kill the cancer cells
• The mABs therapy is usually administered through an intravenous infusion, however, there are a few mABs you have
as a subcutaneous injection
• All treatments have side effects and can vary from person to person. Examples such as tiredness, flu-like symptoms,
headaches can occur, as well as allergic reaction can occur during treatment
Monoclonal Antibody Therapy (mABs)
mAbs stop cancer cells taking up proteins:
mAbs trigger the immune system to treat cancer:
mABs carry radiotherapy or cancer drugs:
Bringing together cancer and immune cells:
Talking Therapy
• Talking, counselling and support groups are known collectively as Talking Therapies
• Can be an important way of supporting the mental health of cancer patients and their families. Talking openly with
family and friends can be very helpful, but some patients find this difficult. In these cases, trained counsellors and
psychologists can be invaluable
• Types of therapies: Counselling, Cognitive Behavioural Therapy (CBT), Psychotherapy
• Can help with a range of issues, such as dealing with the diagnosis, depression, severe anxiety, panic attacks and
sleeping disorders
Other Examples
• Stem cell and bone marrow transplants – for some types of cancer (e.g. leukaemia and lymphoma). Used in conjunction with chemotherapy and sometimes radiotherapy
• Watch and Wait – Regular check-ups and tests, as may not need treatment straight away, or never need treatment
• Complementary and Alternative Therapies. Complementary therapies (e.g. acupuncture) are used alongside conventional medical treatment, to help patients feel better, cope with symptoms and side effects, and improve quality of life. Alternative therapies are used instead of conventional medical treatment
• Radiofrequency ablation which uses heat from the radio waves to kill cancer cells
• Photodynamic therapy uses light sensitising drug and lights to destroy cancer cells
• Palliative Treatment – to relieve symptoms, prolong life, make patients more comfortable and improve quality of life, even if they cannot be cured
• Bisphosphonates – help prevent or treat bone loss and reduce the risk of fractures.
Breast and thyroid cancer
Breast Cancer: Invasive breast cancer is the most common form, where cancer cells develop in the milk ducts, spreading through the lining and into surrounding tissue. More common in females 1:8, compared to males 1:833. Oestrogen can stimulate cancer cells, therefore risk of cancer development increases with oestrogen exposure. Treatments include breast conserving surgery (lumpectomy/wide local incision/partial mastectomy/mastectomy/reconstructive); chemotherapy; radiotherapy; hormone therapy (e.g Tamoxifen); monoclonal Ab therapy (e.g. Herceptin); and Talking Therapies
Thyroid Cancer: Rare in the UK. There are several types, with papillary thyroid cancer being the most common. Usually slow growing, but can spread to the lymph nodes. Risk factors include exposure to high levels of radiation or radiotherapy, family history of thyroid cancer, or having other certain cancers such as breast cancer, testicular cancer or non-Hodgkin lymphoma. Treatment includes thyroidectomy, radioactive iodine treatment, and Talking Therapies.
Non-Hodgkins Lymphoma
A cancer which starts in the lymphatic system (part of the immune system) which affects lymphocytes. The affected lymphocytes multiply in an abnormal way and begin to collect in parts of the lymphatic system, such as the lymph nodes. These cells lose function to fight infection, which makes the individual more vulnerable to infection. There are many sub-types such as B-cell NHL and T-cell NHL, which will have different characteristics and treatment plans. NHL is more common in adults but can also affect children, and slightly more men than women are affected. The most common symptoms is a painless swelling in a lymph node. Over 13,000 people are diagnoses with NHL each year in the UK.
Acute Myeloid Leukaemia
A cancer of the white blood cells, specifically the monocytes and granulocyte cells, which progresses quickly and aggressively, requiring immediate treatment. Symptoms usually develop over a few weeks and worsen over time, such as tiredness, losing weight and unusual bruising or bleeding. A rare cancer with around 3,100 people being diagnosed with it each year in the UK. Risk of developing AML increases with age and is most common in people over 75 years. There is no national screening programme for AML in the UK
Testicles
• The testes are part of the male reproductive system
• They are two small oval shaped organs which hang below the penis in a pouch of skin called the scrotum
Testicular Cancer:
A cancer which affects males, when abnormal cells in a testicle divide and grow in an uncontrolled way. The type of cancer depends on the type of cell the cancer starts in, with 95% starting in the germ cells that make sperm.
This is known as ‘germ cell testicular cancer’. This form has two main subtypes: seminomas and non-seminomas. Surgery (orchidectomy), chemotherapy and radiotherapy are the most common treatments, as well as Talking Therapies. The symptoms can include a lump or pain in the teste. A blood test and ultrasound can help in making a diagnosis. Although a rare cancer, it is the most common type of cancer in men aged between 15 to 49 years. Around 2,400 men are diagnosed with testicular cancer each year in the UK. The cause is not always known, but it is thought some people may be more at risk, e.g. those with a close relative who had testicular cancer (father, brother), having undescended testes, previously had testicular cancer or being white British
