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Chapter 11
Abnormal mammograms without calcifications are more
likely to call attention to DCIS of the small cell type than the
large cell type, regardless of the growth pattern (solid, crib-
riform, or mixed) of the lesion.
53
Linear calcifications are a
marker of necrosis, and granular calcifications are associated
with DCIS without necrosis.
53
DCIS that overexpresses the
human epidermal growth factor 2 (
HER2
) oncogene is more
likely to have calcifications detected by mammography than
is a HER2 negative carcinoma.
54
Extent of mammographic
calcifications, presence of either a radiographically or a clini-
cally evident mass, and solid architectural type of DCIS have
been demonstrated to be significantly associated with inva-
sion on final excision.
55
Unusual mammographic presentations
of DCIS occur
when the lesion has a configuration that suggests a benign
tumor or invasive carcinoma. These patterns, reflective of
associated soft tissue masses, are found in less than 10% of
mammographically detected DCIS.
45,56–59
In one series, 8%
of DCIS were represented mammographically by stellate le-
sions without calcifications,
59
and in another report, 3.6%
of DCIS presented as stellate opacities.
56
Three were pure
DCIS, and four proved to be DCIS arising in benign radial
sclerosing lesions or “radial scars.” Microinvasion was found
in only one case, despite the radiologic appearance suggest-
ing invasive carcinoma in all instances. At the other end of
the spectrum, DCIS may be harbored by radiologically cir-
cumscribed lesions and appear to be benign.
57
In addition
to carcinoma arising in a fibroadenoma, these are usually
examples of solid papillary DCIS or nodular foci of comedo-
carcinoma. Microinvasion may be present.
57
in 12% of pure comedocarcinomas, and in 50% of cases with
both patterns.
49
In patients who undergo mastectomy, ex-
tension of DCIS to the nipple or subareolar region is more
frequent with comedo than with cribriform–micropapillary
DCIS.
49
The likelihood of detecting multifocal DCIS radio-
logically and pathologically is related to the size of the lesion
as determined by either procedure.
44,50
Multifocality is ap-
preciably more frequent in lesions larger than 2.0 to 2.5 cm
than in smaller foci of DCIS. Carlson et al.
48
reported that
the mean size of multifocal DCIS (3.1 cm) was significantly
greater than the size of nonmultifocal lesions (1.95 cm).
The mammographic appearance of microcalcifications
bears some relationship to the histologic type of the lesion,
but, as noted by Stomper and Connolly,
51
“there is consider-
able overlap, and the predominant histologic subtype can-
not be predicted on the basis of the microcalcification type
with a high degree of accuracy.” Predominantly linear calci-
fications are found significantly more often in comedocar-
cinomas than in cribriform, papillary, or solid types, which
typically contain granular calcifications.
49,51
Nonetheless,
22% of linear calcifications were associated with noncom-
edocarcinomas, and 47% of granular calcifications occurred
in comedocarcinomas in one series.
51
The presence of exten-
sive casting-type microcalcifications occupying more than
one quadrant in a mammogram was associated with high-
grade DCIS, multifocal invasive duct carcinoma, and axil-
lary nodal metastases in 33% of 12 patients who had lymph
nodes examined.
48
Image analysis of calcifications has had some success in
discriminating between comedo and noncomedo DCIS.
52
FIG. 11.1.
DCIS, radiologic–pathologic correlation.
A:
Radiograph showing branching linear calcifica-
tions found at biopsy to be in high-grade DCIS with necrosis (“comedo” type).
Inset on left
: typical
“comedo” appearance on cut section.
Inset on right
: cross section of a duct with high-grade
in situ
carcinoma with central necrosis and calcification.
B:
Clustered, rounded punctate calcifications at the
site of cribriformDCIS (
inset
).
Inset
images are from cases other than those shown in the radiographs.
