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Chapter 11
FIG. 11.7.
DCIS, clear cell.
A:
Solid carcinoma with necrosis
and calcification.
B,C:
Intermediate nuclear grade in DCIS.
D–E:
Micropapillary and cribriform DCIS. Note apocrine-
type cytoplasmic features in some cells.
approximately 50% of cases. Whereas some structural com-
binations, such as papillary– or micropapillary–cribriform
and solid-comedo, occur relatively more often than others,
there is considerable heterogeneity with respect to growth
patterns.
115
The probability of structural variability increases
with the size of the lesion. Needle core biopsy samples may
not be representative of the diverse growth patterns in a
single case. The histologic diagnosis of DCIS should list the
structural types in order of decreasing prominence, placing
the dominant pattern first.
Cytologic features, especially at the nuclear level, tend to
be more homogeneous than the growth pattern in a given
case. Some combinations of growth patterns and cytologic
appearances occur more frequently, such as classic comedo
DCIS composed of poorly differentiated pleomorphic cells
or the low nuclear grade typically present in micropapillary
DCIS. Heterogeneity is illustrated by lesions composed of
small, cytologically low-grade nuclei growing in a solid pat-
tern or by high-grade nuclei found in some examples of mi-
cropapillary DCIS (Fig. 11.9). The presence of two or more
structural patterns that have different cytologic features is
particularly unusual (Fig. 11.10). Classification schemes de-
veloped to take cognizance of the heterogeneous distribu-
tion of nuclear grade and necrosis across the spectrum of
