28
Liver and Pancreas
Table 28.2 Comparison of Different Types of Hepatocellular Carcinoma
Well-differentiated
cell type
Moderately
differentiated cell type
Poorly differentiated
cell type
Pleomorphic
large-cell type
cellular arrangement
General cytologic pattern
Many tissue fragments
and cohesive groupings
Numerous naked nuclei
and rare cohesive tissue
fragments
Cohesive groupings, loose
groupings, and solitary cells
Solitary cells and loose
groupings
Sinusoidal endothelial lining
Common findings, except
for microtrabecular and
microacinar subtypes
Occasionally seen along
intact groups
Occasional seen
Absent
CELLS
Average size
Relatively small
Intermediate
Relatively large
Large to giant
Nuclear to cytoplasmic ratio
Higher than normal
hepatocytes
Intermediate
High
Low
Cohesion between cells
Good
Good in the intact cells
Rather poor
poor
nuclei
Shape
Round (mostly)
Round
Round or ovoid
Variable ovoid
Location
Central
Central
Central or peripheral
Peripheral
Size
Small
Intermediate
Large
Variable
Prominent nucleoli
Unusual
Frequent
Frequent
Relatively common
Multinucleation
Unusual
Unusual
Unusual
Frequent
cytoplasm
Quantity
Less than normal
Intermediate
Scanty
Abundant
Bile production
Common
Uncommon
Rare
Frequent
Hyaline globules
Uncommon
Uncommon
Occasional
Rare
Tumors of Intrahepatic Bile Duct
Bile Duct Adenoma
Bile duct adenomas are small, firm nodules, rarely exceeding
1 cm in diameter and usually located beneath Glisson's capsule.
They are composed of small, well-formed bile ducts embedded
in a mature fibrous stroma.54 They are usually solitary but when
multiple may mimic metastatic carcinoma.55
Cytology
Many cohesive clusters of bile duct epithelial cells, usually
columnar in type, are seen. Ductal cells do not show atypia
(Fig. 28.47). No cholestasis is noted. Hepatocytes are not found.
Fibroblasts or fragments of fibrous tissue may be seen in vari-
able numbers but are usually under-represented in FNA smears
compared with the fibrous element observed in tissue sections
because they are difficult to aspirate.
Cholangiocarcinoma
Cholangiocarcinomas may arise anywhere between the papilla
of Vater and the small branches of the bile ducts within the liver,
but they originate most often from the large hilar bile ducts at
the bifurcation of the common hepatic duct or from the extrahe-
patic bile ducts.54 Intrahepatic cholangiocarcinoma is much less
common than hepatocellular carcinoma. Cholangiocarcinoma
is known to follow
C. sinensis
infestation, hemochromatosis,
and Thorotrast injection,56 and the tumor occasionally arises in
Fig. 28.46 Hepatocellular carcinoma, pleomorphic large-cell type.
Solitary, giant tumor cells with abundant cytoplasm, and binucleated and
multinucleated tumor cells. Tumor cells contain nuclei with multiple nucleoli.
FNA smear (Papanicolaou x HP).
patients with chronic ulcerative colitis.54 Histologically, cholan-
giocarcinoma is a ductal-type adenocarcinoma of the cuboidal
or columnar cell type. Much more fibrous stroma is present in
cholangiocarcinoma than in hepatocellular carcinoma, and the
tumor is much less vascular. Mucin is usually demonstrable but
rarely abundant. Cholangiocarcinomas with prominent secretory
activity are only occasionally encountered in our daily work.
891
previous page 880 ComprehensiveCytopathology 1104p 2008 read online next page 882 ComprehensiveCytopathology 1104p 2008 read online Home Toggle text on/off