Invasive breast carcinoma - IARC

A
B
Fig. 2.67 Fibroma. A The sectioned surface shows a white fibrous tumour. B The neoplasm is composed of spindle-shaped cells with abundant collagen. C Oedema
is striking in this fibroma associated with Meigs syndrome.
C
a n d rogenic manifestations {3252}.
Patients with the rare variant of
luteinized thecoma associated with
s c l e rosing peritonitis present with
abdominal swelling, ascites and symptoms
of bowel obstruction {520}.
M a c r o s c o p y
Thecomas may be small and non-palpable,
but they usually measure 5-10 cm.
The sectioned surface is typically solid
and yellow, occasionally with cysts,
haemorrhage or necrosis. Typical thecomas
are almost invariably unilateral;
only 3% are bilateral. Luteinized thecomas
associated with sclerosing peritonitis
are usually bilateral.
H i s t o p a t h o l o g y
Typical thecomas are characterized by
cells with uniform, bland, oval to spindle
shaped nuclei with abundant, pale, vacuolated,
lipid-rich cytoplasm. Individual
cells are invested by reticulin. Mitoses
a re absent or rare. Rare l y, the nuclei
may be large or bizarre {3210}. The
f i b romatous component commonly contains
hyaline plaques and may be calcified.
Extensively calcified thecomas
tend to occur in young women {3194}.
R a re l y, thecomas include a minor component
of sex cord elements {3211}.
Luteinized thecomas contain lutein
cells, individually or in nests, in a backg
round often more fibromatous than thecomatous.
Oedema and microcyst formation
may be striking.
I m m u n o p ro f i l e
Thecomas are immunoreactive for
vimentin and alpha-inhibin {482,562,
1 4 9 9 , 1 8 1 6 , 2 1 8 1 , 2 2 1 1 } .
Somatic genetics
Trisomy and tetrasomy 12 have been
demonstrated in tumours in the thecom
a - f i b roma group by karyotypic analysis
and fluorescence in situ hybridization
{1635,1653,2221,2635,2862}. This
c h romosomal abnormality is not, howeve
r, specific to tumours in this gro u p
since it has also been found in some
benign and borderline epithelial
tumours, as well as in occasional granulosa
cell tumours {2209,2221}.
Prognosis and predictive factors
R a re l y, a typical or luteinized thecoma
with nuclear atypia and mitotic activity
may metastasize {1819,3074,3252},
although most cases re p o rted as "malignant
thecomas" are probably fibro s a rc o-
mas or diffuse granulosa cell tumours.
Patients with luteinized thecomas associated
with sclerosing peritonitis may
experience small bowel obstruction,
and several have died of complications
related to peritoneal lesions, but there
has been no re c u r rence or metastasis of
the ovarian lesion {520}.
Fibroma and cellular fibroma
D e f i n i t i o n
F i b romas are stromal tumours composed
of spindle, oval or round cells
p roducing collagen. In cellular fibro m a s
the cells are closely packed, collagen
is scanty, and the mitotic rate is
i n c re a s e d .
Fig. 2.68 Cellular fibroma. The tumour is cellular but shows no cytological atypia and has a low mitotic rate.
E p i d e m i o l o g y
F i b romas account for 4% of all ovarian
tumours. They are most common in middle
age (mean 48 years) {709}; less than
10% occur before age 30, and they
occur only occasionally in childre n
{ 3 2 8 } .
150 Tumours of the ovary and peritoneum