Acute Presentations Secondary to Cancer

Question 1

Name 6 acute presentations you may see as a result of the underlying cancer?

Answer 1

1. Hypercalcaemia
   2.Bowel Obstruction
2. Ascites
   4.Maligant/metastatic spinal cord compression
3. Superior vena cava syndrome
4. Raised intracrainial pressure

Question 2

What is hypercalcaemia?
How does it present in oncology patients?
What is the treatment?

Answer 2

• Elevated calcium levels in the blood
• Presents with confusion most commonly, other symptoms, dehydration, nausea/vomiting, (bones, moans, groans, stones)
• Treatment is 3L IV 0.9% NaCl fluid over 24 hours and IV bisphosphonates e.g. Zolendronic acid

Question 3

Why do patients presenting with oncological hypercalcaemia often not have symptoms of kidney stones?

Answer 3

Because the calcium level has risen so quickly that the stones dont have time to develop, so often they dont have symptoms of kidney stones but instead symptoms of confusion.

Question 4

Why do cancers cause hypercalcaemia?

Answer 4

1. Cancer can spread to the bones (bone metastases) which causes the bone to be broken down and thus calcium released into the blood.

2.Some tumors can produce parathyroid related protein (PTHrP), a hormone that has similar effects to parathyroid hormone (PTH). PTHrP increases bone resorption (breakdown) and decreases calcium excretion by the kidneys, leading to hypercalcemia.

Question 5

When treating hypercalcaemia, Bisphosphonates must be given 24 hours after IV fluids have been given. Why?

Answer 5

Because bisphosphonates are nephrotoxic, so need time for the kidneys to recover from the fluid.

Alternatively can check the eGFR after giving the fluids to determine the kidney function.

Depending on what the eGFR is, determines the dose of bisphosphate to be given.

Lower the eGFR the lower the dose of bisphosphonate to be given.