Interventional radiology

Question 1

what is the advantage of cryoablation over thermoablation?

Answer 1

can monitor ablation zone during procedure

Question 2

what is the disadvantage of cryoablation over thermoablation?

Answer 2

cryoshock - systemic inflammatory response leading to hypotension, respiratory compromise, DIC, multiorgan failure (rare)

Question 3

what are the stages of the cryoablation procedure?

Answer 3

1. cell shrinkage and dehydration (freeze)
2. cell swelling and bursting (thaw)
3. apoptosis, cleaning up of cellular debris

Question 4

renal cell carcinomas make up what % of all adult cancers?

Answer 4

2%

Question 5

what indicates a stage 1A renal cell carcinoma?

Answer 5

1. tumor less than 4 cm in greatest dimension

2. confined to kidney

Question 6

what kind of tumor diagnosis can be made on imaging only?

Answer 6

hepatoma

Question 7

what is the best option for long term life expectancy in patients with hepatomas?

Answer 7

liver transplant

Question 8

what is the US incidence of hepatocellular carcinoma?

Answer 8

3.4 / 100,000

Question 9

what is the #1 worldwide risk factor for hepatocellular carcinoma?

Answer 9

hepatitis B

Question 10

what is the top risk factor for hepatocellular carcinoma in the US?

Answer 10

hepatitis C

Question 11

what is the mainstay treatment for hepatocellular carcinoma?

Answer 11

local regional therapy

Question 12

what hepatocellular carcinoma treatments are curative?

Answer 12

1. transplant
2. surgical resection
3. percutaneous ablation

Question 13

when is surgical resection of the liver contraindicated?

Answer 13

cirrhosis

Question 14

what are the featuers of transarterial chemoembolization (TACE)?

Answer 14

1. delivery of highly concentrated chemotherapy in a lipid medium combined with arterial embolization resulting in tissue hypoxia and death
2. takes advantage of dual blood supply of liver with tumor supply exclusively from hepatic artery

Question 15

in liver tumors the blood supply comes from which system?

Answer 15

hepatic artery

Question 16

TACE is indicated for what patient population?

Answer 16

patients who do not qualify for transplantation, resection, or local ablation

Question 17

what is the mechanism of radiofrequency ablation?

Answer 17

directed alternating current to create ionic agitation, frictional heat, and cell death

Question 18

what is the mechanism of microwave ablation?

Answer 18

delivery of electromagnetic radiation causing agitation of water molecules in surrounding tissue producing friction and heat resulting in cell death

Question 19

what are the criteria for choosing radiofrequency / microwave ablation therapy?

Answer 19

1. tumors 3 cm or less

2. must have ablation zone of 5-10 mm

Question 20

what is radioembolization?

Answer 20

intra-arterially delivered microspheres emitting high dose radiation (Yttrium 90) for treatment of unresectable liver tumors

Question 21

radioembolization is indicated for what three types of tumors?

Answer 21

1. metastatic colon
2. primary hepatoma
3. metastatic neuroendocrine to the liver

Question 22

what is the mechanism for radioembolization?

Answer 22

microspheres lodge preferentially in neo-vessels of tumor - minimizes radiation exposure to the liver

Question 23

when does malignant pleural effusion occur?

Answer 23

up to 15% of malignancy cases

Question 24

what are the most common cancers associated with malignant pleural effusion?

Answer 24

1. lung
2. breast
3. ovarian

Question 25

how is malignant pleural effusion managed?

Answer 25

1. periodic thora/paracentesis 2. chest tube with chemical pleurodesis 3. tunneled pleural / peritoneal catheter placement for home fluid drainage