Invasive breast carcinoma - IARC

A
Fig. 1.144 Mammary osteosarcoma. A The sectioned surface shows a well delineated, solid mass with focal haemorrhage. B The spindle cell component of the
tumour invades the adipose tissue and is admixed with abundant bony frabeculae.
B
Prognosis and predictive factors
Both the myxoid and pleomorphic variants
of liposarcoma can recur and
metastasize. Axillary node metastases
a re exceptionally rare. Recurre n c e s
generally develop within the first year
and patients who die from their disease
usually do so within a year of the diagnosis.
Because of the high frequency of
marginal irre g u l a r i t y, complete excision
with tumour free margins is necessary.
L i p o s a rcomas behave part i c u l a r l y
a g g ressively when associated with
p re g n a n c y.
R h a b d o m y o s a r c o m a
D e f i n i t i o n
A tumour composed of cells showing
v a rying degrees of skeletal muscle diff
e re n t i a t i o n .
ICD-O codes
R h a b d o m y o s a rc o m a 8900 / 3
Alveolar type 8920 / 3
Pleomorphic type 8901 / 3
E p i d e m i o l o g y
P u re primary rhabdomyosarcoma of
the breast is very uncommon, and,
although primary mammary rhabdom
y o s a rcoma has been described,
it usually re p resents a metastasis from
a soft tissue rhabdomyosarcoma
occuring in children, young females
or males {2402}. More fre q u e n t l y, rhabd
o m y o s a rcomatous diff e rentiation may
be observed in older women as an
h e t e rologous component of a malignant
phyllodes tumour or a metaplastic
c a rc i n o m a .
Pathology
Primary rhabdomyosarcoma has been
reported in adolescents {773,1166,1198,
2402}, when it is predominantly of the
alveolar subtype; the pleomorphic subtype
has been reported in older women
over forty {2871}.
Metastatic rhabdomyosarcoma to the
breast is again predominantly of the alveolar
subtype {1166,1248}. The primary
lesion is usually located on the extremities,
in the nasopharynx/paranasal sinuses
or on the trunk {1166}. A metastasis
from an embryonal rhabdomyosarcoma
to the breast is less frequent {1166,
2531}.
Metastatic breast tumours may occur as
part of disseminated disease or as an
isolated lesion.
Mammary osteosarcoma
Definition
A malignant tumour composed of spindle
cells that produce osteoid and/or bone
together with cartilage in some cases.
ICD-O code 9180/3
Synonym
Mammary osteogenic sarcoma.
Epidemiology
Accounting for about 12% of all mamm
a ry sarcomas, pure osteosarc o m a s
must be distinguished from those originating
in phyllodes tumours or carc i-
n o s a rcomas. Absence of connection to
the skeleton, which should be confirm e d
by imaging studies, is re q u i red for a
diagnosis of a primary mammary
o s t e o s a rc o m a s .
O s t e o s a rcomas occur mainly in older
women with a median age of 64.5 years;
the age range is 27–89 years {2681}.
The vast majority of patients are women
who are predominantly Caucasian. A
prior history of radiation therapy or trauma
has been noted in some women
{ 3 3 1 } .
Clinical features
The tumour presents as an enlarging
mass which is associated with pain in
one-fifth of cases. Bloody nipple discharge
or nipple retraction occurs in
12% of the women. Mammographically,
o s t e o s a rcomas present as a well circumscribed
mass with focal to extensive
coarse calcification. Because of their
p redominantly circumscribed nature ,
they may be misinterpreted as a benign
lesion {3072}.
M a c r o s c o p y
O s t e o s a rcomas vary in size from 1.4 to
13 cm; most are about 5 cm in size and
a re sharply delineated. The consistency
varies from firm to stony hard depending
on the pro p o rtion of osseous diff e re n t i a-
tion. Cavitation and necrosis are seen in
larger tumours.
Histopathology
The histopathological appearance and
immunophenotype are similar to that of
Mesenchymal tumours
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