Diagnostic ultrasound ( PDFDrive )

604 PART II Abdominal and Pelvic Sonography
A
B
C
D
FIG. 17.5 Biopsy of Cavernous Hemangioma. (A) Contrast-enhanced CT scan shows a 1.5-cm vascular mass in left lobe of the liver. (B)
Transverse ultrasound demonstrates a hypoechoic ellipsoid mass in a fatty iniltrated liver. (C) Ultrasound-guided biopsy using an 18-gauge needle.
(D) Histologic specimen shows endothelial-lined vascular spaces (arrow) diagnostic of cavernous hemangioma, as well as small, round, fat globules
(dashed arrow) within hematoxylin and eosin–stained hepatocytes.
patient has a known primary malignancy (Fig. 17.5). Although
cavernous hemangiomas are vascular lesions, these masses have
undergone successful percutaneous biopsy without signiicant
complications. 46-48 Particular care must be taken to avoid direct
puncture of cavernous hemangiomas without intervening liver
parenchyma because this may result in signiicant bleeding. 49
Normal overlying liver may tamponade potential bleeding from
the hemangioma in these cases. Signiicant bleeding ater direct
puncture of hypovascular liver masses is less of a concern.
here has been increasing interest in biopsy of suspected
hepatic adenomas as a result of evolving classiication schemes
and subtyping. Diferent subtypes carry diferent potential for
bleeding and malignant transformation and this has implications
for patient management. 50 Although biopsy of hepatic adenoma
is safe, there remains a small risk of discordant pathology results
between initial biopsy and either subsequent biopsy or surgical
resection specimen based on pitfalls in pathologic interpretation
and occasional overlap in histologic features between adenoma,
focal nodular hyperplasia, and hepatocellular carcinoma. In a
series that included biopsy of 60 suspected hepatic adenomas,
6 (10%) showed discordant at time of follow-up pathology,
including 4 later diagnosed as focal nodular hyperplasia and
two later diagnosed as hepatocellular carcinoma. 51
Percutaneous ultrasound-guided biopsy of portal vein
thrombus has proved to be a safe and accurate diagnostic
procedure for staging of hepatocellular carcinoma, although also
performed less frequently in the context of advanced MRI
techniques. 52
Liver biopsies are relatively safe, with an overall signiicant
complication rate of less than 1%. 16,24,53-59 Hemorrhage is most
common. Such signiicant bleeding complications are more likely
to occur in the biopsy of patients with malignancy and those
with acute liver failure, chronic active hepatitis, or cirrhosis. 58,60,61
Most complications occur soon ater the biopsy procedure, with
about 60% occurring within 2 hours and 80% within 10 hours. 58
Several large series report mortality of percutaneous liver biopsy
as 0.1% or less. 27,58-60
Pancreas
Despite the growing use of endoscopic ultrasound (EUS) and
EUS-guided FNA, percutaneous biopsy of pancreatic tumors
remains necessary in some cases when the tumor is in the tail