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Chapter 11
FIG. 11.19.
DCIS, micropapillary.
A:
The cells have high-
grade nuclei. There is cellular debris and central necrosis
in the ducts.
B:
Apocrine cytology and intermediate nuclear
grade.
C:
An unusual micropapillary DCIS with intermediate
nuclear grade and crystalloids.
FIG. 11.20.
DCIS in collagenous spherulosis.
A:
The spherules simulate a cribriform pattern.
B:
Stellate fibrils are visible in some spherules. Note the thin bands of basement membrane that
define the perimeter of spherules. The carcinoma cells show moderate nuclear pleomorphism and
intermediate nuclear grade. The carcinoma cells were immunoreactive for E-cadherin.
solid papillary DCIS may be quite inconspicuous and easily
overlooked. Another ambiguous situation arises when there
is prominent secondary lumen formation in micropapillary
DCIS (Fig. 11.15). This process can encompass a substantial
part of the overall duct lumen. Generally, the growth pattern
of micropapillary DCIS is oriented to the circumference of
the duct, whereas in cribriform DCIS there is a more even
distribution of microlumina across the duct without periph-
eral orientation. Difficulty in classification also arises when
the intraductal proliferation is almost entirely solid with
rare microlumina (Fig. 11.26). The differential diagnosis
of cribriform DCIS includes other lesions such as AdCC,
