Alice Goodman
November 22, 2010 (New York, New York) — Although cross-sectional imaging is recommended by several well-respected societies as the standard of care for the diagnosis of hepatocellular carcinoma (HCC), many physicians still rely on a liver biopsy for diagnosis.
"This problem is not well recognized. More publicity and education are needed to promote appropriate use of cross-sectional imaging to diagnose HCC," said Matthew S. Johnson, MD, an interventional radiologist at Indiana University in Indianapolis, here at the 37th Annual VEITH Symposium.
Dr. Johnson discussed the importance of cross-sectional imaging as the diagnostic standard. HCC is currently responsible for more than 650,000 deaths each year worldwide, and is the third most common cause of cancer-related death.
"The incidence of HCC is increasing exponentially in the United States because of the increasing prevalence of risk factors such as alcohol consumption, hepatitis B and C, and obesity," he continued.
In 2001, the European Association for the Study of Liver guidelines validated imaging as the preferred method of diagnosis of HCC; this recommendation was strengthened by the American Association for the Study of Liver Disease in 2005. "Still, the vast majority of oncologists do biopsies, driven primarily by the demand from medical oncologists," Dr. Johnson said.
Biopsies are no more sensitive or specific than imaging, he continued, and biopsy carries about a 3% risk for tumor seeding. Although this is a relatively low risk, when seeding occurs and cancer is found outside the liver, the patient is no longer eligible for transplant.
In addition, a needle biopsy can miss a tumor, and pathologists are often unable to differentiate between a high-grade dysplastic nodule and a cancer, Dr. Johnson continued. "Stromal invasion is hard to detect," he emphasized.
"At Indiana University, we consider biopsy potentially dangerous, and we avoid biopsy. . . . [A] biopsy can render a patient transplant-ineligible," he explained.
Three different imaging methods are suitable for the diagnosis of HCC: contrast-enhanced ultrasound, which is not used much in the United States because of the widespread availability of the other 2, more sophisticated, methods — computed tomography scanning and magnetic resonance imaging, which is most commonly used. Both of the latter methods are excellent at detecting cancers larger than 2 cm.
"According to societal guidelines, a lesion larger than 2 cm with hypervascularity and washout on imaging is diagnostic for HCC," Dr. Johnson explained.
"Imaging should be used instead of biopsy to diagnose HCC. There are no downsides to imaging. There is a lot of ignorance out there, and this issue needs to be brought to the attention of the medical community," he stated.
"This is an important topic," agreed Jean-Francois Geschwind, MD, professor of oncology, radiology, and surgery at Johns Hopkins Medical Center, in Baltimore, Maryland. "Biopsies are overutilized in the United States, and decreasing the number of biopsies would lead to fewer procedures and less risk of tumor seeding."
Biopsy should be reserved for the few cases in which a positive result would change management, Dr. Geschwind stated. "Biopsy is useless for early-stage HCC. It can miss the target or not obtain enough tissue to make an accurate diagnosis," he continued.
At Johns Hopkins, a combination of alfa fetoprotein, imaging, and background cirrhosis is used to make the diagnosis of HCC. More than 90% of patients with HCC have cirrhosis. "A hypervascular tumor with background cirrhosis should be considered HCC until proven otherwise," Dr. Geschwind stated.
Dr. Johnson reports serving as consultant to Angiotech, Cook, Boston Scientific, MDS Nordion, and Sirtex. Dr. Geschwind has disclosed no relevant financial relationships.
37th Annual VEITH Symposium: Presented November 18, 2010.
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