Clinical oncology 1/2 Flashcards
cancer
a group of diseases characterised by uncontrolled growth and spread of abnormal cells within a body
types of cancer
1) glandular
- adenocarcinoma
2) skin/mucosa
- squamous cell carcinoma
3) connective tissues
- sarcoma
4) small cell
- small cell carcinoma
5) lymph nodes
- lymphoma
TNM staging
tumour
node
metastases
risk factors for each type of cancer
1) colorectal
- diet and genetic
2) lung
- smoking
3) breast
- genetic
- obestity
4) skin
- UV light
5) cervix
- HPV
6) head and neck
- smoking
- alcohol
- diet/nutrition
- viruses eg HPV, EBV
- immunosuppression
- premalignant oral conditions (leucoplakia, lichen sclerosis)
- radiotherapy exposure
treatment options for cancer
- Surgery
- Radiotherapy
- Chemotherapy
- Hormonal therapy
- Targeted therapies
- Immunotherapy
- Laser therapy
- Cryotherapy
- Best supportive care
- Any combination of these
surgery
aim to remove tumour with clear margins side effects - funcitonal cosmetic risk of anaesthesia
chemotherapy drugs
1) platinum
- cisplatin
2) taxanes
- docetaxel
3) anti metabolites
- 5 fluorouracil
4) alkylating agents
- dacarbazine
5) anthracyclines
- doxorubicin
why may pts be given chemo after
- pts may not have disease and not require it
- pts may get reoccurrence despite chemo
- proportion will be cured, need to assess risk vs benefit
palliative treatmetn
tx to improve symptoms and extend life
side effects of chemo
•General – Nausea and vomiting – Fatigue • Skin – Rash – Hair loss – Extravasation • Nerves – Neuropathy – Hearing loss • Infertility/Premature menopause Bone marrow – Anaemia – Neutropenia – Thrombocytopenia Renal dysfunction • Liver dysfunction • Allergic reaction/Anaphylaxis • Lung toxicity – Fibrosis – Bleomycin • Cardiac Toxicity – Cardiomyopathy
how is chemotherapy given
in cycles
in 3 wks cycle 7-14 days is the highest risk of infection
general rule for dental treatments on chemo
find out cycle all urges work before chemo FBC prior to check not neutropenic or thombocytopenic - neutropenia is neuts <1.0 - thrombocytopenia is platelets <100 - risk of bleeding if platelets <20/30 counts usually cover in the 3rd week
targeted treatment types of drugs
tyrosine kinases inhibitors
monoclonal antibiotics
types of immunotherapy drugs
- PDL1 inhibitors – Pembrolizumab
- immune checkpoint inhibitors – Nivolumab
other bad effects can be controlled by steriods
bone metastases
often a mixture of osteoblastic and clastic lesions
what can be used when there is bone involvement in cancer
bisphosphondates
RANK L inhibitors
radiopharmaceuticals
what is the hallmark of metastatic bone disease
increased bone resorption
bone destruction from tumorus
- tumour cells produce factors (GF and cytokines) that stimulate OB that secret RANK L
- OB increase expression of RANK L
- overexpression of RANK L drives increased formation, function and survival of OC, leading to excessive bone resorption
- Resorption releases growth factors/peptides from the growth matrix that may perpetuate tumour activity
bisphosphnates cycle
- decrease activity of OC
- reduction in release of peptides
- slowed tumour cell growth
- reduced production of PTHrP and other factors
- decrease in bone resorption
denosumab
MC AB - tx for osteoporosis
Rank L
- binds to RANK L preventing activation of RNAK receptor on OC
- binding to Rank L inhibits OC formation, function and survival
- prevents maturation of OC, decreasing bone resorption and breaking vicious cycle of bone destruction
how does radiotherapy work
- ionising radiation interacts with water molecules to make free radicals
- free radicals cause DNA damage, no longer able to divide or multiply
- malignant and normal cells damaged (side effect)
- normal cells can repair if tolerance not exceeded
radiotherapy
Use of ionising radiation to treat cancer
- energy of photos is higher in a therapeutic setting as opposed to diagnostic setting
what can radiotherapy be used as
1) radical
- curative
2) palliative
- to improve symptoms
3) adjuvant
- alongside surgery
4) neoadjuvant
- before surgery
radiotherapy dose and tx depends on
- area being treated
- intention of treatment – curative vs palliative
- all of the cancer cells at different cell cyle stages are killed
curative vs palliative planning
- complex planning
- acute localisation – CT
- longer course of tx
- more early side effects, less late side effects
- can be long term effects eg scarring
Palliative - simple planning
- simple localisation via x ray
- short course of tx
- less early side effects, more late side effects
treatment modalities of radiotherapy
X ray
election tx
brachytherapy (insertion of isotopes into tumour, where cancer is accessible)
CT planned RT
- less dose to underlying structures
- less toxicity
- marks where cancer is
- helps estimate the dose
standard conformal radiotherapy
beam from 3 different directions
concentrated in one area
rapid Arc RT
- machine constantly moves delivering beams
- able to produce different controls and modulate final plan
- stops dosage to structures not needed to have radiotherapy, more control
