Invasive breast carcinoma - IARC

Table 1.09
G l y c o g e n - r i c h (GRCC) and non glycogen-rich clear cell tumours of the breast.
GRCC Lipid rich Histiocytoid Apocrine Hidradenoma Secretory Adenomyo- Metastatic clear
carcinoma lobular carcinoma carcinoma carcinoma epithelioma cell carcinoma
from the kidney
Cell type One One One One Two One Two One
Cytoplasm Empty Foamy Foamy Foamy Empty Foamy/empty/ Empty
granular
Nuclei High grade High grade Low grade Low grade Low grade Low grade Low grade Low grade
PAS + - - + + + + +
PAS diastase - - - + + - +/- -
Mucicarmine - - + + - + - -
Oil red-O - + - - - - - -
Smooth actin - - - - - - + - Vimentin +
S100 - - - - + + + -
GCDFP-15 +/- - + + - - + (apocrine) -
H i s t o p a t h o l o g y
The tumour is characterized by a lobulated
or nested proliferation of a vary i n g
a d m i x t u re of sebaceous cells with abundant
finely vacuolated cytoplasm surrounded
by smaller ovoid to spindle cells
with a small amount of eosinophilic cytoplasm
and without any vacuolization. The
nuclei in both cell types are irre g u l a r l y
shaped to rounded, vesicular with 0 to 2
nucleoli. Mitotic figures are sparse, but
may be focally abundant. Focal squamous
morules may be present focally.
Sebocrine cells with features of both
apocrine and sebaceous cells and noted
in a variety of apocrine lesions have not
been a notable feature of sebaceous carc
i n o m a s .
I m m u n o p r o f i l e
The tumour cells stain positively with pancytokeratin
(AE1/AE3/LP34). In the thre e
cases assessed, immunostains for pro g-
e s t e rone receptor (PR) were positive in
all, two were estrogen receptor (ER) positive,
and one was ER negative.
Neither has the smaller second cell population
or the squamous metaplasia that
may be present in sebaceous carcinoma.
Prognosis and predictive factors
Not much is known about the behaviour
of these tumours. The 7.5 cm tumour was
t reated by radical mastectomy, but none
of the 20 axillary nodes was positive
{2876}. Another recently re p o rted case
was associated with extensive metastases
with sebaceous diff e rentiation evident
at the distant sites {3006}.
Inflammatory carcinoma
Definition
A particular form of mammary carc i n o m a
with a distinct clinical presentation {1607}
believed to be due to lymphatic obstruction
from an underlying invasive aden
o c a rcinoma; the vast majority of cases
have a prominent dermal lymphatic infiltration
by tumour. Inflammatory carc i n o-
ma is a form of advanced breast carc i n o-
ma classified as T4d {51, 2976}. Derm a l
lymphatic invasion without the character-
Differential diagnosis
Apocrine carcinoma with a large population
of sebocrine cells and lipid rich carcinomas
enter the diff e rential diagnosis.
The former invariably has typical apocrine
cells admixed and the latter form s
c o rds and irregular cell clusters with a
m o re subtle vacuolization of the cells.
Fig. 1.63 Sebaceous carcinoma. The cells have abundant finely vacuolated cytoplasm and form rounded
aggregates with a few amphophilic cells present in the periphery.
Invasive breast carcinoma
47