Invasive breast carcinoma - IARC

A
Fig. 2.37 A This polypoid intracystic tumour consists of complex villoglandular structures with abundant stroma. Neither confluence of glands nor destructive infiltrative
growth is present. B Endometrioid borderline tumour of the ovary. Squamous morules appear to form bridges within dilated endometrial glands.
B
into the adjacent tissue and intravascular
growth appears.
Most neoplasms are low grade, whereas
approximately 10% of cases are high
grade and are classified as undifferentiated
ovarian sarcoma. In the past,
tumours with less than 10 mitoses per 10
high power fields were classified as low
grade ESS, whereas tumours with more
than 10 mitoses per 10 high power fields
were traditionally designated high grade
{3208}. However, there is no evidence
that mitotic rate alone alters the outcome,
and all tumours with an appearance
resembling that of endometrial stroma
should be designated endometrioid stromal
sarcoma {438}, whereas those that
lack endometrial stromal differentiation
should be diagnosed as undifferentiated
ovarian sarcoma. The latter is a high
grade neoplasm that is composed of
pleomorphic mesenchymal cells with
distinct variablility in size and shape. The
nuclei are highly atypical with prominent
nucleoli and occasionally resemble rhabdomyosarcoma
or fibrosarcoma.
Immunoprofile
Immunostaining demonstrates the
expression of vimentin and CD10 in ESS.
Muscle-associated proteins are only
focally expressed. Alpha-inhibin was
negative in all cases examined {1681}.
Differential diagnosis
ESS must be differentiated from other
ovarian lesions, including some small
cell tumours. The major problem is to distinguish
ESS from adult granulosa celltumour,
foci of stromal hyperplasia, ovarian
fibroma or ovarian thecoma.
On morphological grounds alone, it is not
always possible to decide whether the
ovarian lesion is a primary ESS of the
o v a ry or a metastatic lesion from a uterine
ESS. Thus, an ovarian ESS should never
be diagnosed unless the uterus is care f u l-
ly examined to exclude a uterine primary.
Should ESS be found in both organs, it is
m o re or less impossible to decide which
tumour is the primary and which is
metastatic. One criterion that establishes
a primary site in the ovary is its continuity
with endometriotic foci in the ovary.
Somatic genetics
Mutation of the TP53 tumour suppressor
gene associated with overexpression of
TP53 protein has been fre q u e n t l y
observed in ovarian sarcomas. These
mutations may occur on the basis of an
impaired DNA repair system in these
tumours {1681}.
Prognosis and predictive factors
Since over one-half of the ESSs have
already spread to pelvic or upper abdominal
sites at the time of diagnosis, the
tumour stage remains the major prognostic
criterion {438}. Whether the neoplasm
is an ESS or undifferentiated ovarian
sarcoma also influences the clinical
course {3208}. ESS often has a favourable
outcome with survival in excess of
5 years even in the context of extraovarian
spread. After 10 years, however, the
tumour-related mortality increases, particularly
if extraovarian manifestations
were noted at the time of diagnosis. Tumour
relapse re p resents an ominous
prognostic sign. Undifferentiated ovarian
sarcomas have a rapid course and a
poor prognosis {3208}.
Radical panhysterectomy is the recommended
therapy. Successful treatment
with progesterone, non-hormonal cytostatic
drugs or radiation has been reported
occasionally in ESS.
Endometrioid borderline tumour
Definition
An ovarian tumour of low malignant
potential composed of atypical or histologically
malignant endometrioid type
glands or cysts often set in a dense
f i b rous stroma with an absence of stromal
invasion.
Synonyms
Endometrioid tumour of low malignant
potential, endometrioid tumour of borderline
malignancy.
Epidemiology
Endometrioid tumours with atypical
epithelial proliferations and lacking stromal
invasion are rare. Their pre c i s e
prevalence is not known because of variation
in diagnostic criteria, but reportedly
they account for 3-18% of malignant
ovarian neoplasms {137,2490,2528}.
Aetiology
These tumours appear to be predominantly
derived from the surface epithelium
of the ovary or endometriosis.
Clinical features
Patients range in age from 22-77 years
{201,2737}. A pelvic mass is palpable in
a majority of patients, and others present
with uterine bleeding. The tumours are
Surface epithelial-stromal tumours 135