LWBK1006-15 LWW-Govindan-Review December 7, 2011 19:5
172 DeVita, Hellman, and Rosenberg’s CANCER: Principles and Practice of Oncology ReviewAnswer 15.10. The answer is C.
Hepatobiliary drainage is one of the main procedures in most interven-
tional radiology suites today. Bile duct obstructions can be divided into
high and low obstructions, an important distinction because the former
are usually referred to interventional radiologists and the latter are usu-
ally treated endoscopically by gastroenterologists. Dilation of isolated
segments or isolated bile ducts occur when the duct is obstructed and no
longer is communicating with the other ducts. These, too, usually fall to
interventional radiologists for treatment. Because the right duct is shorter
than the left, isolated right segmental biliary dilatation is more common
than isolated left segments from a central mass. Percutaneous drains can
only drain a portion of the liver, but that may be all that is required to
cure pruritus. For an infected biliary tree (cholangitis), multiple catheters
may be required to cure sepsis. Because catheters may be in place for
a long time and the remainder of a terminally ill patient’s life, percuta-
neous drainage should be reserved for patients who are symptomatic or
in whom clear benefit will be obtained. Biliary dilatation on its own is
not an indication for drainage.Answer 15.11. The answer is E.
Patients who are scheduled to undergo percutaneous biliary drainage
receive prophylactic antibiotics targeting skin flora to avoid infection from
the procedure. First, percutaneous transhepatic cholangiography is per-
formed to provide information about the biliary tree. This step provides
invaluable information regarding the nature of an obstruction. Drainage
is usually done as a two-step procedure. First, an external drain is used
to cross a level of obstruction. If the patient can tolerate this catheter
with side holes proximal and distal to the obstruction without any exter-
nal drainage, the catheter is converted to an internal one. When external
outputs are high, oral replenishment of electrolytes may be required. In
a majority of patients, drainage can result in rapid recovery of hepatic
function with decrease in liver enzymes and bilirubin.Answer 15.12. The answer is E.
Percutaneous cholecystostomy is a safe procedure in the treatment of
acute cholecystitis (calculus or acalculous) in patients who are unable to
undergo cholecystectomy. Because of its few complications, percutaneous
cholecystostomy can be a useful diagnostic tool in patients with sepsis of
unknown cause. Ultrasound or CT is used for needle guidance. A tran-
shepatic route is usually preferred to minimize intraperitoneal leakage
and subsequent bile peritonitis. Although cholecystography can be a use-
ful diagnostic tool, distension of the gallbladder in the acute setting is
avoided to prevent rupture. In a majority of patients, the catheter will be
left in place until the patient’s condition improves, the tract is established
(2 to 4 weeks), and the tube can be removed. In others, the tube will be
left in place until the time of definitive treatment, which is usually a chole-
cystectomy. In certain high-risk patients, percutaneous stone removal can
be performed via the cholecystostomy. Recurrent disease may be found in
up to 50% of these patients within 5 years. This conservative approach