Haematology & Oncology

Question 1

Oncological Emergency

2021.1 Case based discussion

discuss with an examiner the assessment and management of an adult male patient with a history of metastatic melanoma who has presented unwell with SOB?

Patient requires respiratory support

Answer 1

SHORTNESS OF BREATH IN ONCOLOGY:

DIFFERENTIAL DIAGNOSIS:
- PE
- Pneumoniae (immune compromised, neutropenic)
- Malignant pleural effusion
- Malignant pericardial effusion with tamponade
- Superior vena cava syndrome

Haematological - anaemia
Pneumothorax
Lung tumour burden

ASSESSMENT:

chemotherapy - when last dose
metastatic disease to where ? lungs
prognosis, palliative
goals of care
co-morbidities

POCUS:
PE
Pleural effusion
Cardiac tamponade

Question 2

Sickle Cell Disease

Sickling is exacerbated by:
- hypoxia
- acidosis
- dehydration / hyperviscosity
- fever
- inflammation

Tips:
- When ordering blood transfusion, tell the blood bank that the patient has sickle cell disease. They will provide blood that has minimal risk of causing allo-immunization.

Answer 2

Pain crisis (diagnosis of exclusion)
- pain is legitimate (don’t assume patient is malingering)
- are taught how to cope with pain with distraction methods
- ask them is this their typical sickle cell pain
- what pain meds have they taken prior to presenting
- what works for you in terms of your analgesia requirements
- treat pain adequately with opiates

Hydroxyurea - reduce pain episodes, reduce admissions, reduce transfusions

Refer to haematologist and sickle cell clinic for education

HISTORY:
- does this feel like usual pain crisis?
- analgesia regimen at home
- multiple transfusions?
- baseline Hb?
- what sickle cell complications in the past?

INVESTIGATIONS:
- Hb, reticulocyte count

COMPLICATIONS:

Pain crisis - erythrocyte sickling causes micovascular occlusion (usually in bone) –> pain

Acute chest syndrome:
- high mortality
- vicious cycle with microvascular occlusion of lungs, hypoxia worsens sickling
- present with fever, hypoxia, pulmonary infiltrates on CXR
- need urgent blood transfusion or exchange transfusion

Aplastic crisis
- severe drop in Hb
- present with syncope and in shock
- reticulocyte is dramatically low or zero
- need immediate blood transfusion

Splenic sequestration
- tender hepatosplenomegaly
- high bilirubin, ALT, LDH
- high reticulocyte

Sepsis (functionally asplenic)

Priapism

Stroke
- common in children
- urgent CT and blood transfusion or exchange transfusion

Avascular necrosis

Renal failure
- usually have low Cr

Blunt eye trauma –> hyphaema and traumatic glaucoma

MANAGEMENT:

Analgesia:
- paracetamol
- NSAIDs - regular ibuprofen
- morphine 5-10mg IV
- ketamine PCA

Oxygen - only if hypoxic
Can suppress bone marrow, increasing need for transfusions

IV fluids - hyperchloraemic metabolic acidosis can increase sickling
- need to give 5% dextrose with 0.45% NS
- large volumes can cause pulmonary oedema

BLOOD TRANSFUSIONS:
- need to discuss with haematologist first
- accept low Hb of 70
- want to prevent alloimmunisation. alloimmunization will make future transfusions very difficult when they really need it.

no steroids for acute pain crisis. causes rebound pain when the steroids are stopped.

Question 3

Hypercalcemia

Causes:
**Primary hyperparathyroidism (parathyroid adenoma)
**Malignancy (PTH related protein)
non-small cell lung cancer
multiple myeloma
breast cancer

Secondary hyperparathyroidism - chronic renal failure (chronic hypocalcemia –> increased PTH)

• sarcoidosis (increased GI absorption)
• Vitamin D toxicity (increased GI absorption)
• thiazides (reduce renal excretion)

Answer 3

Clinical Features:
- polydipsia, polyurina, dehydration

Stones:
- renal stones

Psychiatric moans:
- confusion
- hallucinations

Bones:
- bone pain/fractures

Abdominal groans:
- abdominal pain, nausea/vomiting
- pancreatitis
- peptic ulcer disease

ECG:
- short QT

MANAGEMENT:

Dilute serum calcium and promote diuresis and renal excretion

• Rehydration with IV fluids (0.9% NS, not hartmann’s) 4-6L over 24hr

Decrease calcium resorption from bone - inhibits osteoclast activity

• Bisphosphonates
  Pamidronate 60-90mg over 4hrs
• Calcitonin
  Salcalcitonin 100IU SC/IM/IV TDS

Decrease calcium absorption from the gut
- Corticosteroids – prednisone 30mg daily (in malignancy and sarcoidosis)

Forcibly remove excess calcium from the circulation

• Haemodialysis

Question 4

Tumour Lysis Syndrome

Renal failure in oncology

Pre-renal:
- hypovolemia (vomiting)

Renal:
RTA (nephrotoxic medications - chemotherapy, tumour lysis syndrome)
- infiltrating tumours

Post renal:
pelvic masses compressing ureters

Answer 4

Electrolyte and metabolic derangements secondary to rapid cell destruction, usually following chemotherapy for lymphoma or leukemia. These patients present with hyperkalemia, hyperphosphatemia, hypocalcemia, and severe renal failure.

Risk factors:

More common in haematological malignancies

• Burkitt’s lymphoma
• Acute lymphoblastic leukemia

Large tumour burden

Just commenced chemotherapy

Dehydration

Pre-existing renal failure

Pre-existing hyperuricemia

Lab findings:
*hyperuricaemia

• hyperkalaemia
• hyperphosphataemia
• lactic acidosis
• hypocalcaemia

Treatment for tumor lysis syndrome: The first treatment priority is to lower the potassium. Be cautious about giving calcium, as these patients have high phosphate! in case dialysis is needed.

Rasburicase (an enzyme that transforms uric acid into soluble allantoin) is used to manage tumor lysis syndrome

IV Fluids
Allopurinol
Dialysis