Invasive breast carcinoma - IARC

Sex cord-like, neuroectodermal and
neuroendocrine tumours, lymphomas
and leukaemias
F. Nogales
F.A. Tavassoli
Sex cord-like tumours
Definition
Tumours of the uterine corpus that closely
resemble some true ovarian sex cord
tumours.
Epidemiology
Among these rare tumours the most
numerous are the sex cord-like tumours
{511}, which closely resemble some true
ovarian sex cord tumours.
Histopathology
These are diagnosed only when they are
not found within otherwise classical
endometrial stromal or smooth muscle
tumours. Histologically, sex cord elements
are represented by trabecular ribbons
and nodules or isolated cells with
luteinized or foamy cytoplasm that are
histologically and immunohistochemically
identical to ovarian steroid-producing
cells, being strongly positive for alphainhibin,
calretinin and CD99 {167,
1521,1808}. They may be capable of horm
o n e - s e c reting activity {2034}. They
have a prominent epithelial component
that can be tubular, retiform {3247} or
glomeruloid. They also show frequent
positivity for cytokeratins, vimentin,
smooth muscle actin and, occasionally,
epithelial membrane antigen (EMA)
{930}.
Neuroectodermal tumours
Definition
A variety of tumours of the uterine corpus
that show neuro e c t o d e rmal diff e re n t i a t i o n .
Epidemiology
D i ff e rent types of neuro e c t o d e rm a l
tumours are found in the uterus. When
p u re, they usually present in young
patients {1188}; however, when mixed
with carcinoma or carc i n o s a rcoma they
a re usually found in older women {638,
931,2710}. Recently, peripheral primitive
neuro e c t o d e rmal tumour/Ewing
tumour has been re p o rted in both young
{1597} and postmenopausal patients
{ 2 7 1 0 } .
Histopathology
Well diff e rentiated variants with an
appearance similar to low grade astrocytoma
{3201} should be diff e re n t i a t e d
from non-neoplastic fetal parts implanted
in the endometrium following abortion.
Most often, the tumour cells differentiate
into neuroblastic, neuroepithelial, glial
and neuronal elements {1188}.
Peripheral primitive neuro e c t o d e rm a l
tumour/Ewing tumour shows a characteristic
immunophenotype positive for neuron-specific
enolase, vimentin and CD99
as well as the presence of EWS/FLI-1
fusion transcripts.
Prognosis and predictive factors
All neuroectodermal tumours except the
well diff e rentiated astrocytic form s
behave in a highly malignant fashion.
Melanotic paraganglioma
Definition
A tumour morphologically identical to
paraganglioma, but functionally producing
mainly melanin pigment instead of
neuroendocrine granules.
Epidemiology
Only two examples of melanotic paraganglioma
have been described in the
uterus in women 31 and 46 years of age
{2866}.
Macroscopy
Both were incidental findings in uteri
removed for unrelated benign lesions.
The larger lesion was 1.5 cm and
appeared as a black pigmented lesion
on macroscopic examination; the other
was a histological finding.
Histopathology
Both lesions were well circ u m s c r i b e d
and composed of large nests of round or
angulated polygonal cells with abundant
clear or granular pale eosinophilic cytoplasm.
Both cases had psammoma bodies,
and large amounts of coarse melanin
A
Fig. 4.56 Sex cord-like tumour. A Trabecular pattern is prominent. B The neoplasm shows a cord-like pattern.
B
Sex cord-like, neuroectodermal and neuroendocrine tumours, lymphomas and leukaemias 255