Eble JN, Sauter G., Epstein JI, Sesterhenn IA - iarc

A
B
Fig. 4.33 Embryonal carcinoma. A Embryonal carcinoma composed of blastocyst-like vesicles. B Solid type of embryonal carcinoma.
A
B
Fig. 4.34 Embryonal carcinoma. A Papillary type of embryonal carcinoma. B Intratubular embryonal carcinoma. Note the tumour necrosis.
1490} and may be more common in
Orientals when compared to Caucasians
{1276}. In adults, it usually occurs as a
component of a mixed germ cell tumour
and is seen in approximately 40% of
NSGCTs. In adults, it is much more common
in Caucasians than in other races.
The age incidence corresponds to the
age incidence of testicular malignant
mixed germ cell tumours {2564}.
Fig. 4.35 Embryonal carcinoma. Vascular invasion
of embryonal carcinoma.
Clinical features
Signs and symptoms
In children, the median age at the presentation
is 16-17 months but may extend
to 11 years {1274,2244}. There is a right
sided preponderance {1274}. Almost
ninety percent of cases present with an
otherwise asymptomatic scrotal mass
{1274}. Seven percent of cases present
with a history of trauma or acute onset
pain and 1 percent present with a hydrocele
{1274}. Alpha fetoprotein levels are
elevated in 90 percent of cases {1274,
2595}. Ultrasound examination reveals a
solid intratesticular lesion with a different
echo texture from that of the testis.
Tumour spread
Ten to twenty percent of children have
metastases at presentation {1274,2078}.
The nodal spread is to the retroperitoneum
{1274,2244}. In children there
appears to be a predilection for
haematogenous spread, 40% presenting
with haematogenous spread alone {326}.
In 20-26 percent of cases the first site of
clinical involvement is the lungs {326,
1274}. Although it is not clear if retroperitoneal
nodes are also involved in those
cases, in adults, the pattern of spread is
similar to that seen in other NSGCTs.
Macroscopy
Macroscopically pure yolk sac tumours
are solid, soft, and the cut surface is typically
pale grey or grey-white and somewhat
gelatinous or mucoid {1021,1274}.
Large tumours show haemorrhage and
necrosis {2564}.
Histopathology
The histopathological appearance is the
same, regardless of patient age {1021,
1274,2564}. Several different patterns
are usually admixed, and may be present
in equal amounts, although not infrequently
one pattern may predominate
{1201}. Tumours composed entirely of a
single histologic pattern are rare {2564}.
238 Tumours of the testis and paratesticular tissue