Oncology - Oncogenesis, staging, grading and treatment Flashcards
List some carcingogenic agents which induce mutations:
What protects us from cancer?
What happens when this is reduced?
- chemicals - asbestos, coal tar
- radiation - UV, x-rays, nuclear fission
- viruses - EBV, HPV
- environmental factors - smoking, alcohol, obesity
Immune surveillance protects us from cancer
- cancer cells present antigen that may be recognised by immune system - leading to cancer cell death
Loss of immune surveillance makes cancers grow unchecked
- immune system loses ability to recognise cancer cells as foreign
- novel anticancer therapy reawakens the immune system to cause cancer cell death - immunotherapy
Who and how is cancer graded?
What does it try to establish?
How is cancer staged?
Histological specimen analysed by pathologist
Grading tries to establish how aggressive a cancer is - how fast cells are dividing
Grade I - well differentiated
Grade IV - poorly differentiated
Staging - how advanced cancer is in terms of metastatic spread
- implications for choice and success of treatments
T - tumour (1-4)
N - nodes (0-3)
M - metastases (0-1)
How is cancer recognised?
- made on screening - breast, cervix, colorectal
- made when symptoms occur: sometimes early, may be late, presentation depeds on primary site and site of any symptomatic metastases
List some local presentations of cancer:
Systemic effects?
Local effects:
- lump
- bleeding - urine, stool, sputum, post coital, inter-menstrual
- local pain
- local obstruction - dysphagia, constipation, urinary
Systemic effects:
- fatigue, weight loss, anaemia from blood loss, pain from metastases, nausea and vomiting
How is cancer diagnosed?
- blood tests - specific tumour markers, routine bloods
- biopsy or surgical resection specimen - histology and surface antigens
- imaging - USS, CT, MRI, PET, bone scan
How is cancer managed?
Treatment options?
Management is multidisciplinary
- surgery
- chemotherapy
- radiotherapy
- hormonal treatment
- immunotherapy
- bone marrow transplant
Give an overview of chemotherapy:
Chemotherapy - systemic anticancer treatment
- given by specialist oncologists
- conventional chemo is systemic Rx (oral or IV) given in a course
- different drugs act on different parts of cell division pathways to kill cancer cells
- also harm normal cell divisions - hence side effects
- can be curative or palliative intent
- can be neoadjuvent to downstage a cancer prior to surgery
List some side effects of chemotherapy:
Chemo affects rapidly dividing cells
- blood count falls: risk of neutropenic sepsis (lack of WBC), bleeding risk with thrombocytopenia, anaemia contributes to fatigue
- GI tract - mucositis, diarrhoea/constipation, nausea/vomiting, anorexia, hair loss, fatigue, memory and concentration problems
Give an overview of radiotherapy:
Radiotherapy
- given by oncologists
- ionising radiation directed to localised cancer mass
- induces DNA damage and cell death in cancer cells, but also damages normal cells
- can be used in curative treatment but also palliation
- newer techniques minimise dose to normal or susceptible tissues
List some side effects of radiotherapy:
What are hormonal treatments aimed at?
- GI tract - diarrhoea
- Head - hair loss
- Bladder - radiation cystitis
- Salivary glands - xerostomia
- Oral mucosa - mucositis - inflammation of the lining
General: fatigue, skin redness/inflammation - radiation dermatitis
Hormonal treatments: for hormonal sensitive tumours
- breast cancer (oestrogen)
- prostate cancer (testosterone)
What is immunotherapy and how does it work?
Immunotherapy - increases immune surveillance
- works by helping bodys own immune system recognise and attack cancer cells
- medically designed monoclonal antibodies against antigens expressed on cancer cell surface
- increasing number of ‘ibs’ and ‘abs’available, mainstream cancer treatment in melanoma and lung cancer
- ongoing trials
