Renal Cell Carcinoma

Question 1

List some DDx for R loin pain, haematuria and fever?

Answer 1

Renal:
o Neoplastic- RCC, polycystic kidney disease
o Infective- pyelonephritis, glomerulonephritis (drugs, SLE), glomerulosclerosis (HIV, infection, heroin, obesity)
o Vascular- acute tubular necrosis (ischaemia, toxins- aminoglycosides)
o Mechanical- renal calculi, hydronephrosis
o Renal dysfunction- nephrotic or nephritic syndrome
o AI- Goodpasture’s syndrome

Post renal:
o Ureter trauma- surgical (vasectomy)
o Mechanical- renal calculi 
o Neoplastic- uroepithelial tumour 
o Infectious- cystitis

Pre-renal
o Haem disease- coagulopathy, sickle cell disease

Haematological malignancies- leukaemia, lymphoma, MM

Immunosuppressed with opportunistic infection- HIV, chemotherapy

Question 2

List some peripheral signs of kidney disease?

Answer 2

• GIT: anorexia, nausea, vomiting, diarrhoea
• skin changes (pruritis, dry skin, ecchymoses)
• Peripheral neuropathy
• Restless Leg Syndrome
• uraemic frost (crystalized urea, CKD)
• uraemic fetor (ammonia, CKD)
• skin turgor
• urine output (nocturia, polyuria, freq)

Question 3

What imaging would you order to investigate renal disease?

Answer 3

Imaging
o Renal US- masses, cysts, lymphadenopathy 
o Abdo x-ray- kidney stones 
o IV pyelogram (IVP)- visualize kidneys via constrast and x-ray 
o CT- mets, staging 
o CXR
o PET
o Bone scan

Question 4

What changes might be seen in the FBC?

Answer 4

• anaemia (decreased Hb) -> due to decreased EPO production secondary to renal dysfunction
• erythrocytosis (increased Hb) -> increased EPO production secondary to paraneoplastic syndrome (5%)

Question 5

Describe the CT findings of an RCC?

Answer 5

Contrast CT:
Non-contrast, homogenous enhancing mass in R kidney
- lack of contrast uptake -> poor vascularisation and angiogenesis -> thus clear cell carcinoma likely (most common 75%, non-aggressive)

Question 6

What are the anterior relations of the kidney?

Answer 6

Kidneys location: T12-L2

Anterior relations:
• R kidney
- Superior: liver
- Medial: D2 
- Lateral: hepatic flexure of colon
• L kidney
- Superior: spleen, pancreatic tail, splenic artery, splenic vein
- Medial: small intestine, stomach
- Lateral: splenic flexure

Question 7

What are the posterior relations of the kidney?

Answer 7

Kidneys location: T12-L2

Posterior relations:
• Muscles (4): quadratus lumbrorum, psoas major, transversus abdominus, diaphragm
• Nerves (3): subcostal n, iliohypogastric n, ilioinguinal n
• Vessels (2): subcostal artery, subcostal vein
• Bone (1): 12th rib

Question 8

What other effects might you see in a patient RCC?

Answer 8

Local:
o Invasion of collecting system -> haematuria
o Invasion of IVC -> varicocele, lower limb oedema, ascites, hepatic dysfunction
o Invasion of L renal vein -> L testicular varicocele

Paraneoplastic:
o Haemopoietic- polycythemia (increased RBC production in BM)
o Hormone dysfunction- hypercalcaemia (parathyroid hormone-related protein, PTHrP), HTN (renin)
o Hepatic dysfunction- Stauffer syndrome (liver dysfunction from RCC -> deranged LFTs, decreased WCC, fever, necrosis)

Mestastasis: lung (most common), liver, bone

Question 9

In RCC, what is the mechanism of flank pain?

Answer 9

Sensory nociceptive fibre activation -> sympathetic pathway -> sensory neurons T10-11
-> referred to T10-11 dermatomes (due to convergence of somatic sensory fibres at these levels)

Question 10

In RCC, what are possibly mechanisms of lumbar spine pain?

Answer 10

1. Bone mets -> increased pressure within bone -> stretch periosteum
   - > sensation carried by myelinated (fast, A beta and A delta fibers) and unmyelinated (slow, C fibers) sensory neurons
2. Reactive muscle spasm
3. Nerve root infiltration -> compression of nerves by vertebral collapse

Question 11

Describe the innervation of the quadratus lumborum?

Answer 11

Quadratus lumborum

• Innervation: anterior branch T12 and L1-4 nerves
• Function: extends and laterally flexes vertebral column, flexes 12th rib during inspiration

Question 12

Describe the innervation of the psoas major?

Answer 12

Psoas major

• Innervation: anterior rami of L1-3
• Function: thigh flexion, lateral vertebral flexion, trunk balance, trunk flexion

Question 13

Why would a pt with RCC develop a pleural effusion?

Answer 13

Metastatic spread to lungs:
o Transudate: fluid pushed through cap via high pressure
- Imbalance in hydrostatic/oncotic pressures in chest (HF) or external to chest (fluid movement from peritoneal, cerebrospinal or retroperitoneal space)

o Exudate: fluid leaks around cap cells due to inflammation

• Pleural and lung inflammation -> increased cap and pleural membrane permeability
• OR from impaired lymphatic drainage of pleural space
• Causes: infection, malignancy, immunological responses, lymphatic abnormalities