Rosen's Breast Pathology, 4e

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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. 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,

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

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.