Invasive breast carcinoma - IARC

muscle may appear cellular and of fetal
t y p e .
The mucinous epithelium is usually
bland intestinal or gastric-type epithelium,
but sometimes shows borderline or
malignant change. Argentaffin cells,
goblet cells and carcinoid may be seen.
The gonadal stroma may condense
a round areas of mucinous epithelium, a
useful clue to the diagnosis of a SLCT in
a tumour that appears to be a mucinous
cystadenoma. Hepatocytic diff e re n t i a-
tion may be recognized by the pre s e n c e
of bile plugs or an acinar arrangement
of hepatocytes, but immunohistochemi
s t ry is usually necessary to distinguish
hepatocytes from Leydig cells {1904}.
I m m u n o p ro f i l e
Variable positivity is seen in the sex cord
elements for vimentin, keratin and
alpha-inhibin.
The immunoprofile of the hetero l o g o u s
elements is what would be expected
f rom their constituent tissues. The mucinous
elements show more extensive
staining for cytokeratin 7 than for cytokeratin
20. They are positive for epithelial
membrane antigen and may be
focally positive for chro m o g r a n i n .
Leydig cells are negative for pan-keratin,
CAM 5.2 and AFP but show intense
positivity for vimentin and alpha-inhibin.
These findings distinguish them fro m
hepatocytes. AFP may be identified in
e n d o d e rmal-like structures in some
c a s e s .
Prognosis and predictive factors
The small number of cases of this
tumour re p o rted make it difficult to
d e t e rmine the significance of individual
elements. Heterologous mesenchymal
elements (skeletal muscle or cart i l a g e )
or neuro-blastoma imply a poor outcome
with 8 of 10 patients dead of disease
{2291}. In contrast, gastro i n t e s t i n a l
epithelium or carcinoid as the hetero l o-
gous element does not have pro g n o s t i c
significance {3207}.
Retiform Sertoli-Leydig cell
tumour and variant with retiform
e l e m e n t s
D e f i n i t i o n
R e t i f o rm SLCT is composed of anastomosing
slit-like spaces that re s e m b l e
the rete testis and comprise 90% or
m o re of the tumour. Tumours with at
least 10% but less than 90% re t i f o rm
elements are classified as being of intermediate
or poor diff e rentiation and qualified
"with re t i f o rm elements".
E p i d e m i o l o g y
R e t i f o rm tumours tend to occur in
younger patients but may occur at any
age {3209}. Virilization is less common
in tumours with a re t i f o rm pattern .
M a c r o s c o p y
R e t i f o rm tumours may contain papillae
or polypoid structure s .
H i s t o p a t h o l o g y
Like heterologous elements, re t i f o rm
a reas occur only in SLCTS of interm e d i-
ate and poor diff e rentiation {2471,3209}.
They vary from slit-like spaces to are a s
comprising a complex microcystic patt
e rn. Dilated spaces may be continuous
with sex cord areas of the tumour. The
lining cells may be flattened and nonspecific
or cuboidal and sert o l i f o rm. The
lumens frequently contain variably
inspissated eosinophilic material re s e m-
bling colloid. Within the SLCT category,
re t i f o rm tumours shows the highest incidence
of heterologous elements {3209}.
I m m u n o p ro f i l e
R e t i f o rm areas stain with keratin and
show moderate staining for alpha-inhibin,
with a reversed pattern seen in sex
c o rd and stromal areas of the tumour.
Vimentin may show subnuclear localization
in the re t i f o rm areas.
D i ff e rential diagnosis
S e rous tumours, yolk sac tumours and
malignant müllerian mixed tumours may
resemble a re t i f o rm SLCT {3209}. The
p resence of primitive gonadal stro m a ,
h e t e rologous elements, Leydig cells
and/or alpha-inhibin positivity assists in
making the diagnosis.
Prognosis and predictive factors
A p p roximately 25% of patients with
S L C Ts that contain re t i f o rm elements will
have an aggressive course {3209}.
Many have stage II or higher disease,
poor diff e rentiation and/or hetero l o g o u s
e l e m e n t s .
Sertoli cell tumour
Definition
A neoplasm composed of Sertoli cells
arranged in hollow or solid tubular formations
with rare, if any, Leydig cells.
Simple or complex annular tubules are
dominant in those lesions that occur in
association with the Peutz-Jeghers synd
ro m e .
Fig. 2.80 Sertoli cell tumour, lipid-rich variant (folliculome lipidique). The Sertoli cells have abundant vacuolated
cytoplasm filled with lipid.
E p i d e m i o l o g y
S e rtoli cell tumours are rare {2882}.
Patients range in age from 2-79 years.
156 Tumours of the ovary and peritoneum