PART TWO
Diagnostic Cytology
Fig. 14.8 Aggregates of dysplastic Barrett's epithelium. (A) These are frayed and irregular. The nuclei are enlarged, hyperchromatic, and crowded.
Polarity is distorted. Note the absence of individually dispersed intact abnormal cells. Although mucin depletion and nuclear enlargement are seen, significant
nuclear atypia is absent (Papanicolaou x MP). (B) A sheet of irregularly arranged abnormal nuclei with high N/C ratios, nuclear membrane irregularities, and
hyperchromasia. Note that the group still maintains cohesion. These features of dysphasia may be difficult to distinguish from those of well-differentiated
adenocarcinoma (Papanicolaou x HP).
Fig. 14.9 Esophageal adenocarcinoma. Brushings include loose clusters of cells and individually scattered cells with large pleomorphic nuclei with
distorted membranes, nuclear overlap, hyperchromatic chromatin, and distinct nucleoli (Papanicolaou (A) x MP, (B) x HP).
brushings. As might be expected, many of the cytologic criteria
for dysplasia and adenocarcinoma are the same.1,48,53-55 In both,
there is a reduction in the degree of intercellular cohesion, so
that in comparison to benign Barrett's epithelium, the smears
contain smaller cellular aggregates with frayed irregular margins
(Figs 14.8 and 14.9). In addition, there are variable numbers of
individually dispersed abnormal cells. In adenocarcinomas, these
isolated malignant elements may be numerous, whereas indi-
vidual abnormal cells are very sparse in brushings from patients
with pure dysplasia (Fig. 14.9). In both carcinoma and dysplasia,
polarity is also reduced, so that within cellular aggregates there is
a haphazard array of crowded and overlapped abnormal nuclei.
Attendant with this is a reduction in obvious cellular borders with
the formation of syncytia. Dysplastic aggregates may be somewhat
larger than those typical of adenocarcinoma. Cytoplasmic mucin
is greatly reduced.1,48,53-55,80,86 Cytoplasm remains more delicate
than that typically seen in squamous cell carcinoma. Also evident
are the nuclear changes generally ascribed to malignant cells.
The nuclei are enlarged and variably pleomorphic; their shapes
vary from round to ovoid to a characteristic elongated (cigar-
shaped) appearance. The latter are especially common in both
dysplasia and well-differentiated adenocarcinomas. The nuclear
membranes are thick and slightly irregular in contour. Hyper-
chromasia is generally evident, as are large nucleoli that may be
multiple and irregular in shape. In brushings from patients with
adenocarcinoma, but not in those with only dysplasia, the smear
background has a "dirty" appearance, reflecting a tumor diathe-
sis secondary to invasion and necrosis (Fig. 14.9, Table 14.4).
In summary although dysplasia can be suggested it may not be
absolutely distinguished from a well-differentiated adenocarci-
noma on cytologic grounds. Furthermore, dysplasia may not be
accurately graded by cytologic examination; this requires a tissue
biopsy for histologic correlation.
Although ancillary studies have not been widely used in the
cytologic work-up of patients with Barrett's esophagus, a few
studies have reported the application of villin immunohisto-
chemistry for the diagnosis of Barrett's metaplasia, as well as
expression of P21 and P53 nuclear proteins for detection of
dysplasia and adenocarcinoma in the setting of Barrett's.86-90
Additionally a recent study utilizing DNA FISH probes on
brush cytology showed the loss of 17P 13.1 (P53); loss of Y
chromosomal and polysomy of chromosomes 17 and 9 were
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