Invasive breast carcinoma - IARC

Intraductal papillary neoplasms
G. MacGrogan
F. Moinfar
U. Raju
Definition
P a p i l l a ry neoplasms are characterized
by epithelial proliferations supported by
f i b rovascular stalks with or without an
intervening myoepithelial cell layer.
They may occur anywhere within the
ductal system from the nipple to the terminal
ductal lobular unit (TDLU) and
may be benign (intraductal papilloma),
atypical, or malignant (intraductal papill
a ry carcinoma).
Intraductal papilloma
A proliferation of epithelial and myoepithelial
cells overlying fibrovascular stalks
creating an arborescent structure within
the lumen of a duct.
Intraductal papilloma of the breast is
broadly divided into central (large duct)
papilloma, usually located in the subareolar
region, and peripheral papilloma
arising in the TDLU {2092}. The confusing
term "papillomatosis" should be
avoided as it has been used for usual
ductal hyperplasia as well as for multiple
papillomas.
ICD-O code 8503/0
Central papilloma
Synonyms
Large duct papilloma, major duct pap
i l l o m a .
Epidemiology
The incidence of the various forms of
intraductal papillary lesions is uncert a i n
due to the lack of consistent term i n o l o-
g y. Overall, less than 10% of benign
b reast neoplasms correspond to papillomas
{413,1098}. Central papillomas
can occur at any age, but the majority
p resent during the fourth and fifth
decades {1098,1945}.
Clinical features
Unilateral sanguineous, or sero -
sanguineous, nipple discharge is the
most frequent clinical sign, and is
observed in 64-88% of patients {3148}. A
palpable mass is less fre q u e n t .
Mammographic abnormalities include a
c i rcumscribed re t ro - a reolar mass of
benign appearance, a solitary retro-areolar
dilated duct and, rarely, microcalcifications
{401,3148}. Small papillomas
may be mammographically occult
because of their location in the central
dense breast and usually lack of calcification.
Typical sonographic feature s
include a well defined smooth-walled,
solid, hypoechoic nodule or a lobulated,
smooth-walled, cystic lesion with solid
components. Duct dilatation with visible
solid intraluminal echoes is common
{3176}.
Galactography shows an intraluminal
smooth or irregular filling defect associated
with obstructed or dilated ducts,
or a complete duct obstruction with re t-
Fig. 1.98 Distribution of papillomas in breast.
rograde flow of contrast material.
Galactography may be useful to the
b reast surgeon in identifying and localizing
the discharging duct, prior to duct
excision {3148}.
Macroscopy
Palpable lesions may form well circumscribed
round tumours with a cauliflowerlike
mass attached by one or more pedicles
to the wall of a dilated duct containing
serous and/or sanguineous fluid. The
size of central papillomas varies considerably
from a few millimetres to 3-4 cm or
larger and they can extend along the
duct for several centimetres.
A
B
Fig. 1.99 Central papilloma. A Smooth intraluminal filling defect associated with duct dilatation. B W e l l
defined smooth wall cystic lesion with a solid component.
Fig. 1.100 Papilloma, gross. Nodular mass in a
cystic duct.
76 Tumours of the breast