CHAPTER X CHAPTER 4 - Cancer et environnement

A
Fig. 4.46 Teratoma. A Longitudinal ultrasound image of the left testis (cursors) shows the normal parenchyma
being replaced by complex, multiseptated, cystic mass. B Gross specimen confirms the cystic nature of the mass.
A
Fig. 4.47 Epidermoid cyst. A Transverse ultrasound image through the lower pole of the testis shows a well
marginated, hypoechoic, oval mass (arrow). Multiple concentric rings are visualized giving an "onion-skin"
appearance. B Epidermoid cyst within the stroma of the testis. Note the laminated structure.
nancies. Some have classified foci indistinguishable
from primitive neuroectodermal
tumours as malignant irrespective of
size {1797} whereas others recognize a
nodule equal to or greater than a (4x
objective) microscopic field as PNET
{1722}. Monodermal teratomas have
been described as struma testis {2427},
pure cartilagenous teratoma {2427}, and
possibly epidermal (epidermoid) cyst.
Teratoma can show invasion of paratesticular
tissue and intra and extratesticular
vascular invasion.
B
B
Immunoprofile
The differentiated elements express the
immunophenotype expected for that
specific cell type. Alpha-fetoprotein production
occurs in about 19-36% of teratomas
in intestinal and hepatoid areas
{1196,1198,1807}. Other markers include
alpha-1 antitrypsin, CEA and ferritin
{1198}. hCG can be seen in syncytiotrophoblastic
cells. PLAP is also demonstrable
in glandular structures {346,1615,
1807,2658}.
Genetics
Teratomas of the infantile testis are
diploid {1350,2413}. Karyotyping, as
well as CGH, even after microdissection
of the tumour cells, has failed to demonstrate
chromosomal changes in these
tumours [{1792,2054} for review]. It
remains to be shown whether the recently
identified constitutional translocation
between chromosome 12 and 15 as
found in a family with a predisposition to
sacral teratoma at young age {2724} is
involved in the genesis of this type of
tumour. In contrast to the diploidy of
teratomas of neonates and infants, teratoma
is hypotriploid in adult patients
{1763,1963,2209}. In fact, teratomas as
part of TGCTs have similar genetic
changes compared to other components.
In addition, the fully differentiated
tumour cells found in residual teratomas
as a remainder after chemotherapy of a
non-seminoma of adults, are
hypotriploid {1542}.
Prognosis
The behaviour of teratoma in the two different
age groups is strikingly different. In
the prepubertal testis, teratoma is benign
{2264}. In the postpubertal testis, despite
appearance, teratoma shows metastases
in 22-37% of cases. Teratoma
shows mostly synchronous metastases;
in 13% of cases, it is metachronous
{1806}. If it is associated with a scar
(burned out component), the metastatic
frequency is 66%. In a series from
Indiana, 37% of 41 adult patients with
pure teratoma showed synchronous
metastases {1471}. Teratoma may
metastasize as such {793,1204,1966,
2128,2509}, or in some instances precursor
cells may invade vascular spaces
and differentiate at the metastatic site
{1800}. The cellular composition of
metastases may differ from that of the
respective primary tumour {548}.
Dermoid cyst
Definition
A mature teratoma with a predominance
of one or more cysts lined by keratinizing
squamous epithelium with skin appendages,
with or without small areas of
other teratomatous elements. Epidermoid
cysts lack skin appendages.
ICD-O code 9084/0
A
Fig. 4.48 A Teratoma. B Teratoma. Carcinoid tumour within the testis.
B
Testicular dermoid cyst is a specialized,
benign form of cystic teratoma that is
analogous to the common ovarian
tumour {2670}. It is rare, with less than 20
cases reported {126,324,349,629,976,
1392,1609,2670}. Most have been in
young men who presented with testicular
masses, but an occasional example has
244 Tumours of the testis and paratesticular tissue