Diagnostic Cytology
Fig. 28.69 Serous microcystic adenoma of the pancreas. Flat sheets of
Fig. 28.70 Serous microcystic adenoma of the pancreas. Scanty
glycogen-rich simple epithelium. Histology (periodic acid-Schiff stain x HP).
flat sheets of ductal epithelium in a background of serous fluid.
(Romanowsky x MP).
Table 28.3 Comparison of Autoimmune Pancreatitis and Well-
differentiated Ductal Adenocarcinoma in Pancreatic
Fine-needle Aspirates
Wel l-d ifferentiated
ductal adenocarcinoma
Acinar cells
Ductal cell
Fewer and smaller
sheets of ductal
Many groups, vacuolated
cells intermingled with
nonsecretory cells
Relatively regular,
Irregular, tight, three-
dimensional arrangement;
occasional monolayer
Variation in
nuclear size
Apparent in some groups
lymphoid tangles, and
plasma cells; fibrosis;
debris may be present
in some passes
Neutrophils sometimes
Fig. 28.71 Serous microcystic adenoma of the pancreas. Bland
epithelial cells that have round or ovoid nuclei, in a sheet arrangement.
FNA smear (Papanicolaou x MP).
com posed o f inn um era b le sm all cavities and few er larger cysts
con tain in g clear fluids. The cavities o f the cysts are lin e d by
cuboid o r c o lu m n a r e p ith elial cells con tain in g ab und ant glyco-
gen (Fig. 28.6 9 ) . U ltra stru c tura l studies have show n th a t features
o f the neoplastic e p ith elial cells are com parable w ith those o f
n o rm a l centroacinar cells.
Serous m icrocystic adenom as are d iffic u lt to aspirate. T he aspi-
rates consist o f clear flu id c on tain in g very scanty ductal epithe-
liu m (Fig. 28.70). They occur sing ly o r in cohesive groupings,
in eith er sheets o r palisades (Fig. 28.71) . The e p ith elial cells are
e ith er c o lu m n a r o r cuboid. They have m oderate am ounts o f
cytoplasm and sm all ro u n d o r o vo id nuclei. N u c le o li are ind is-
tinct. A few fo a m y macrophages m ay be present. O th e r cellu-
la r com ponents are rarely seen in the FN A smears fro m serous
m icrocystic adenom as.100 I f th is tu m o r is suspected, one can use
a bigger needle to o b tain a sam ple fo r cell b loc k h isto lo g y to
clinch the diagnosis.
Key features of serous microcystic adenoma
• C lin ic a l: in c id e n ta l fin d in g in m id d le-a g ed p atients.
• C T scan: h o n e yc o m b p a tte rn o f m ic rolac un ae , w ith th in
septae sep arating d iffe re n t segm ents.
• C lea r serous flu id c o n ta in in g scanty sheets o f b e n ig n d uctal
e p ith e liu m .
• C e ll b lo c k is h e lp fu l in e sta b lis h in g th e diagnosis.
Mucinous Cystic Neoplasm
M ucinous cystic neoplasm s account fo r 5.7% o f p rim a ry pan-
creatic tum ors, w ith a fem ale to m ale ra tio o f 90:10 and w ith a
m ean age between 40 and 50 years.101,102 A p p roxim a te ly 7 0 -9 0 %
o f m ucinous cystic neoplasm s arise in the b od y o r ta il o f the pan-
creas. The tum ors are u su ally m u ltilo c u la te d or, rarely, u nilo cu -
lated. C T scans usually dem onstrate a thick-w alled cystic mass
w ith o u t connection to the ductal system. H istologically, the cysts
previous page 889 ComprehensiveCytopathology 1104p 2008 read online next page 891 ComprehensiveCytopathology 1104p 2008 read online Home Toggle text on/off