924
Chapter 33
more than the normal thickness that varies from 1 ± 0.2 mm
over the upper outer quadrant to 1.5 ± 0.4 mm over the
areola.
269
Despite diffuse dermal involvement by tumor em
boli, direct invasion into the skin with cutaneous ulceration
is found only in advanced cases. Paget disease of the nipple is
uncommon, although the nipple is often retracted.
269
When
present, Paget disease is typically accompanied by intraductal
carcinoma of major lactiferous ducts.
Microscopic Pathology
“Primary inflammatory carcinoma” is usually a manifes
tation of infiltrating duct carcinoma that is almost always
poorly differentiated
268,269
(Fig. 33.34). Tumor emboli are
usually encountered throughout the breast, but this may
rarely be an inconspicuous feature. Many of the vascular
spaces containing carcinoma are devoid of red blood cells
and are considered to be lymphatics. However, channels of
similar structure and caliber containing erythrocytes and tu
mor emboli are also encountered, especially in patients with
extensive vascular and lymph node involvement. Hence,
a distinction between blood vessel and lymphatic emboli
is often difficult in hematoxylin and eosin (H& E) stained
sections.
6 cm in greatest diameter).
268
The majority of the carcinomas
were central, or they were large enough to occupy virtually
the entire breast. Diffuse induration of the mammary paren
chyma was palpable, and the skin was visibly thickened, mea
suring 2 to 8 mm thick (averaging 4 mm). This is substantially
FIG. 33.33.
Inflammatory carcinoma, mastectomy.
Inva-
sive carcinoma is present throughout the breast. There is
peau d’orange
change in the skin.
FIG. 33.34.
Primary inflammatory carcinoma.
A:
The pri-
mary tumor is an infiltrating, poorly differentiated ductal
carcinoma.
B:
Clusters of carcinoma cells lie in a dilated
lymphatic channel.
C:
Carcinomatous emboli in a vascular
channel with red blood cells.
