Oncology Flashcards
Which score is used to stage cancers?
TNM staging classification
T - size and extent of main tumour
N- number of nearby lymph nodes that have cancer
M- has the cancer metastasised
What is the mild, moderate, severe classifications of corrected hypercalcaemia?
corrected calcium is unbound, ionised calcium
mild: 2.6-3.0
moderate: 3.1- 3.39
severe: >3.4
What are the main causes of hypercalcaemia?
primary hyperparathyroidism *
malignancy (bone mets, squamous lung cell carcinoma, breast cancer, myeloma)*
+ diuretics, dehydration, thyrotoxicosis, sarcoidosis
How does hypercalcaemia present?
BONES - osteoporosis
STONES - renal stones
THRONES - constipation, abdominal pains, vomiting
PSYCHIC OVERTONES - Depression, confusion, drowsy
+ arrthymias, fatigue, weight loss
How would you investigate possible hypercalcaemia?
adjusted serum calcium PTH U&Es phosphate ECG - shortened QT interval
How is hypercalcaemia managed?
- diagnose underlying cause with blood tests
- IV 0.9% saline 3-4 L a day (monitor U&Es)
- IV bisphosphonate e.g. zoledronic acid IV
- loop diuretic e.g. furesomide
How is superior vena cava obstruction caused?
SVC provides venous drainage for the head, neck, upper limbs and thorax into the R atrium
WITHIN THE SVC LUMEN - thrombus
WITHIN THE SVC WALL - direct tumour invasion
OUTSIDE THE SVC - lung tumour, ALL, lymphoma
How does SVC obstruction present?
dyspnoea chest pain flushing in the face oedema in upper limbs neck and face swelling distended veins in upper limbs, neck, chest wall dizziness visual disturbance
How is possible SVC obstruction investigated?
clinical diagnosis
CT scan
How is SVC obstruction managed?
- oxygen therapy and diuretics for symptomatic relief
- high dose steroids
- endovascular stenting **
+ radiotherapy/ chemotherapy if already have diagnosis of lung cancer
What is tumour lysis syndrome?
cancer cells breakdown and release substances into the blood
when lots of cancer cells breakdown rapidly, the kidney cannot remove the toxic substances quick enough
there is accumulation of substances in the blood causing abnormal blood levels (hyperuricaemia, hyperkalaemia, high phosphate, hypocalcaemia)
When does tumour lysis syndrome occur commonly?
most commonly occurs 2-3 days after initiating chemotherapy when large number of cancer cells killed
also common in haematological malignancies and treatment sensitive tumours
List the possible symptoms of tumour lysis syndrome
weakness, fatigue
arrhthymias - palpitations, chest pain (hyperkalaemia)
AKI - reduced UO, nausea (high phosphate)
gout (increased uric acid levels)
How is acute tumour lysis syndrome managed?
- full blood count!!!! U&E, serum uric acid, serum phosphate, urinalysis
- IV fluids
- rasburicase (recombinant urate oxidase)
- correct high potassium with calcium gluconate + IV insulin and dextrose
- phosphate binders
- dialysis in severe cases
how can tumour lysis syndrome be prevented?
- identify high risk patients e.g. leukaemia, lymphomas, combination chemotherapy
- prophylaxis measures - oral allopurinolol or IV rasburicase (recombinant orate oxidase) prior to first chemotherapy treatment
- monitor patients closely during treatment of chemotherapy
What are the abnormalities in the blood tests in tumour lysis syndrome?
high uric acid
high potassium
high phosphate
low calcium
+ raised urea and creatinine (Aki)
What is the definition of neutropenic sepsis?
<0.5 x 10^9 neutrophil count AND temperature of >38 degrees/ 2 readings of >37.5 degrees for 2 hours
Who is at most risk of neutropenic sepsis?
highest risk during the first 6 weeks of cytotoxic chemotherapy (usually occurs 7- 14 days after starting chemo)
How should neutropenic sepsis be managed?
- observations - temp, RR, HR, BP
- septic screen (FBC, U&E, CRP, blood cultures, creatinine, LFT, clotting screen, blood gas) +/- CXR, urinalysis
- oxygen therapy
- IV broad spec antibiotics - TAZOCIN started within 1 hour of admission (do not wait for blood test results)
- IV fluid bolus
- check urine output
How can we prevent high risk patients from getting neutropenic sepsis?
fluoroquinolone given as a prophylaxis
List the possible causes of spinal cord compression?
- malignancy
- trauma
- prolapsed disc
- inflammation e.g. RA
Where does the spinal cord terminate?
L1
How might spinal cord compression present?
radicular pain
bladder/ bowel dysfunction
LMN signs at level of lesion - fasciculations, muscle weakness, absent reflexes, decreased tone
UMN signs below the lesion - increased tone, brisk reflexes, reduced power , sensory loss
How should spinal cord compression be managed?
- MRI of whole spine
- analgesia
- high dose corticosteroids e.g. dexamethasone
- surgery (if fit for surgery) or radiotherapy ( if unsuitable for surgery e.g. multiple mets)
+ thromboembolism prophylaxis, pressure sore care, long term catheter, bisphosphonates, analgesia, rehab
How is radiotherapy dose measured for palliative care patients?
high dose per fraction but overall small dose total (in order to reduce short term side effects)
the larger the dose, the increasing chance of cure
What sort of dose is given via radiotherapy if aiming to cure patients?
high dose total but over many fractions to reduce long term side effects
List the acute side effects of radiotherapy
nausea and vomiting anorexia mucositis oesophagitis diarrhoea
How does chemotherapy work?
works by stopping the cell cycle and preventing replication of cancer cell to promote cell death
so it also affect normal healthy cells
but targets cells that are dividing rapidly more
How can cytotoxic chemotherapies be classified?
- alkylating agents e.g. cisplatin
disrupt DNA synthesis by preventing DNA replication and RNA transcription - anti metabolites e.g. methotrexate
effect the synthetic phase of the cell cycle, effective against rapidly growing tumours - natural products e.g. mitomycin
List the general side effects of chemotherapy
nausea taste change constipation alopecia skin rashes heart failure hepatic impairment immune suppression peripheral neuropathy
