Invasive breast carcinoma - IARC

u p period currently available for these
women, it appears as if "DCIS per se is
not a life threatening disease" {794}. The
deaths that do occur are related to an
undetected invasive carcinoma present
at the time of the initial diagnosis of
DCIS, pro g ression of residual incompletely
excised DCIS to invasive carcinoma,
or development of a de novo invasive
carcinoma elsewhere in the breast
{794}.
A
B
Clinical features
In countries where population scre e n-
ing is perf o rmed, the vast majority of
DCIS (>85%) are detected by imaging
alone. Only approximately 10% of DCIS
a re associated with some clinical findings
and up to 5% is detected incidentally
in surgical specimens, obtained for
other reasons. Clinical findings, which
may be associated with DCIS include (i)
palpable abnorm a l i t y, (ii) pathological
nipple discharge and (iii) nipple alterations
associated with Paget disease.
Imaging
Mammography constitutes by far the
most important method for the detection
of DCIS. In current screening pro g r a m s ,
10-30% of all detected ‘malignancies’
a re DCIS {810,1280}. In the majority of
cases, mammographic detection is
based on the presence of significant
m i c rocalcifications that are associated
with most of these lesions {1206,
1 2 3 1 , 2 7 9 6 } .
Calcifications associated with well diff
e rentiated DCIS are usually of the laminated,
crystalline type re s e m b l i n g
psammoma bodies. They often develop
as pearl-like particles in the luminal
spaces within the secretion of the
tumour and appear on the mammogram
as multiple clusters of granular microcalcifications
that are usually fine. These
multiple clusters reflect the frequent lobular
arrangement of this type of DCIS.
Calcifications associated with poorly
d i ff e rentiated DCIS, are, histologically,
almost exclusively of the amorphous
type developing in the necrotic areas
of the tumour. They appear on the mammogram
as either linear, often branching,
or as coarse, granular microcalcifications.
Calcifications associated with the intermediately
diff e rentiated DCIS may be
of either the amorphous or the laminated
type.
C
Fig. 1.86 Ductal carcinoma in situ images. A This galactogram was performed because of pathologic discharge
from a single duct. On the galactogram multiple filling defects and truncation of the duct (approx. 4 cm
behind the nipple) are demonstrated. B Low grade cribriform DCIS. In this patient, an ill circumscribed nodular
nonpalpable (8 mm) low grade cribriform DCIS was detected by ultrasound. C MRI of an intermediate grade
papillary DCIS. A strongly enhancing somewhat ill circumscribed lesion is visualized at 6 o’clock in the
patient’s right breast (coronal plane). D High grade comedo-type DCIS. Highly suspicious coarse granular and
pleomorphic microcalcifications are shown, which follow the ductal course indicating presence of a DCIS.
A
B
Fig. 1.87 A High grade DCIS with solid growth pattern is usually associated with fragmented, branching, casting
type calcifications. Microfocus magnification, detail image. The rod-like, “casting-type” calcifications are
characterisitc for Grade 3 DCIS. B High grade DCIS with micropapillary growth pattern is usually associated
with dotted casting type calcifications.
About 17% of the lesions lack histologic
evidence of microcalcifications; they are
either mammographically occult or manifest
as an architectural distortion, a nodular
mass or nonspecific density {1206}.
D
Size, extent and distribution
Size/extent is an important factor in the
management of DCIS. The assessment of
extent of DCIS is complex and needs in
optimal conditions the correlation of the
68 Tumours of the breast