Tumors In The Liver - Diagnostic Problems
Case 6 -
Bile Duct Adenoma
Linda D. Ferrell, M.D.
Wendy L. Frankel, M.D.
40 year old man with cirrhosis who underwent a liver
transplantation. The explant liver contained a 1 cm tan firm nodule in that appeared different from the
Case 6 - Figure 1 - Cirrhotic liver with a nodular proliferation of ducts in a fibrotic area, low power
Case 6 - Figure 2 - Ductular structures with a tubular appearance in a fibrotic stroma with some lymphocytes, medium power
Case 6 - Figure 3 - Ducts with no cytologic atypia, high power
Cirrhotic liver with a nodular proliferation of ducts
in a fibrotic area. Ductular structures with a tubular appearance and no cytologic atypia in a fibrotic
stroma with some surrounding lymphocytes.
Diagnosis- Bile Duct Adenoma
Bile Duct Adenoma
Clinical features. Bile duct adenoma (BDA) is a less common lesion than biliary
hamartoma. The designation of "adenoma" may be a misnomer as most feel this lesion does not not
represent a true neoplasm, but rather represents a localized ductular proliferation at a site of previous
injury or a form of peribiliary gland hamartoma. The lesions are usually discovered as incidental
findings, and may be biopsied at time of surgery (often for frozen section) to exclude metastatic
Gross features. BDAs are small lesions, usually less than 2 cm in diameter, firm,
white to grey-tan, and well-circumscibed. Typically, they are noted in a subcapsular location, but they
can be located deep in the parenchyma. BDAs can be single or multifocal.
Microscropic features. The ductules in BDA are more uniform in size without the
appearance of dilatation and with less intervening fibrous stroma than the ductules in hamartomas.
Although the fibrous stroma is typically not as pronounced as that in hamartoma, the amount of
collagenization may vary considerably, and focal zones of dense collagen can be present. The ductules
tend to have tubular or curvilinear shapes and are lined by cuboidal epithelium with bland round to oval
nuclei without mitotic activity. Mucinous metaplasia of the epithelium, alpha-one-antitrypsin droplets,
and neuroendocrine differentiation may be seen in the tubular lining cells. Typically, residual portal
tracts are often preserved within or near the edge of the lesion and small aggregates of lymphocytes are
present at the periphery.
Clinical features. Biliary hamartoma (BH), or the von Meyenburg complex, is
thought to represent a ductal plate malformation, and so these lesions are often seen as part of the
spectrum of polycystic disease in the liver and other organs.
Gross features. BH is a small (usually less than 0.5 cm), grey to white,
irregularly shaped lesion; multifocality is common.
Microscopic features. BH consists of numerous small to medium-sized ductules,
which are typically more dilated than normal ducts, and are separated by dense collagen. They typically
are located within and at the edge of a portal zone. The ductules are lined by small, cuboidal to
flattened epithelium with round to oval nuclei, are also more irregularly shaped than normal ducts, and
may contain eosinophilic debris or inspissated bile.