Invasive breast carcinoma - IARC

A
mal luteinization, can be confused with a
Sertoli-Leydig cell tumour. Positive mucicarmine
and PAS-stains with diastase
digestion are of great value in establishing
the diagnosis of a Krukenberg
tumour. Occasional Krukenberg tumours
may closely resemble fibromas on
macroscopic examination and may contain
relatively few signet-ring cells.
Bilaterality and positive mucin stains
facilitate the differential diagnosis.
Distinction between a transitional cell
carcinoma of the urinary tract metastatic
to the ovary and a primary transitional
cell carcinoma may be diff i c u l t
{2100,3220}. Clinical information may be
necessary to resolve the issue.
Renal cell carcinoma rarely metastasizes
to the ovaries; however, when it does, it
must be distinguished from a primary
clear cell carcinoma. The metastatic
tumour usually shows a sinusoidal vascular
pattern, a homogenous clear cell
p a t t e rn without hobnail cells, the
absence of hyalinized papillae and the
absence of mucin {3226}.
A metastatic carcinoid can be confused
B
C
Fig. 2.137 Burkitt-like lymphoma. A T2 weighted sagital computed tomography scan from an 8-year old girl
shows a large pelvic mass. B Sagital section of the ovarian tumour shows a homogeneous, pale surface.
Notice the enlargement of the fallopian tube (FT). C A starry-sky pattern is apparent (B5 fixation).
FT
with a primary carcinoid, granulosa cell
t u m o u r, Sertoli-Leydig cell tumour,
B renner tumour, adenofibroma or
endometrioid carcinoma {2605,3226}.
Bilaterality and extraovarian extension
are important features of metastatic carcinoid.
In the ovary, metastatic malignant
melanoma may be confused with primary
malignant melanoma; the latter is unilateral
and usually associated with a dermoid
cyst. When a melanoma is composed
predominantly of large cells, it
may resemble steroid cell lesions such
as steroid cell tumour or luteoma of pregnancy;
when it is composed predominantly
of small cells it may be confused
with a variety of other tumours characterized
by small cells {3223}. Positive stains
for melanin, S-100 protein, melan A,
and/or HMB-45 should establish the
diagnosis of melanoma.
Sarcomas may metastasize to the ovary
from the uterus or extragenital sites and
may occasionally be discovered before
the primary tumour {3222}. Metastastic
low grade endometrial stromal sarcoma
(ESS) may simulate a primary ovarian
sex cord-stromal tumour. Features helpful
in their distinction include the presence
of extraovarian disease, bilaterality
and the characteristic content of spiral
arterioles in metastatic low grade ESS.
Metastatic epitheliolid leiomyosarc o m a
may have an appearance that simulates
the solid tubular pattern of a Sertoli cell
tumour.
Although lymphoma and leukaemia can
involve the ovaries simulating various primary
tumours, they rarely present clinically
as an ovarian mass. In countries
w h e re Burkitt lymphoma is endemic,
however, it accounts for approximately
half the cases of malignant ovarian
tumours in childhood. Dysgerminoma is
one of the most common and difficult differential
diagnoses. The appearance of
the cell nuclei is very import a n t .
I m m u n o h i s t o c h e m i s t ry for lymphoid
markers and placental alkaline phosphatase
are helpful. Carcinoid, granulosa
cell tumour or small cell carcinoma
can also resemble lymphoma. In patients
with acute myeloid leukaemia, ovarian
involvement in the form of granulocytic
sarcoma ("chloroma") may rarely constitute
the initial clinical presentation of the
disease. Histological examination
reveals a diffuse growth pattern with a
prominent "single file" arrangement of the
tumour cells. Myeloid differentiation can
be demonstrated by the chloroacetate
esterase stain. Immunoperoxidase stains
for lysozyme, CD68, and LCA are also
helpful.
Recognition of the secondary nature of
an ovarian tumour depends on a complete
clinical history, a careful operative
search for a primary extraovarian tumour,
and accurate evaluation of the macroscopic
and histological features of the
ovarian tumour. In rare cases the primary
tumour is not found until several years
after resection of the ovarian metastases
{2605,3226}.
Prognosis and predictive factors
Ovarian metastases often represent a
late disseminated stage of the disease in
which other haematogenous metastases
are also found. The prognosis is, therefore,
poor.
196 Tumours of the ovary and peritoneum