Invasive breast carcinoma - IARC

Mixed germ cell-sex cord-stromal
tumours
A. Talerman
P. Schwartz
This group of neoplasms is composed of
a mixture of germ cell and sex cord-stromal
elements. They have mainly benign
clinical behaviour except in cases with a
malignant germ cell component.
Gonadoblastoma
Definition
A neoplasm composed of tumour cells
closely resembling dysgerminoma or
seminoma, intimately admixed with sex
c o rd derivatives resembling immature
Sertoli or granulosa cells and in some
cases containing stromal derivatives
mimicking luteinized stromal or Leydig
cells devoid of Reinke crystals.
ICD-O code
Gonadoblastoma 9073/1
Epidemiology
Gonadoblastomas typically are identified
in children or young adults with one-third
of the tumours being detected before the
age of 15 {2598}.
Aetiology
Gonadoblastomas are frequently associated
with abnormalities in the secondary
sex organs {2598,2847}. In over 90% of
the cases of gonadoblastoma a Y chromosome
was detected {2598,2605,2849,
2850}.
Localization
Gonadoblastoma is found more often in
the right gonad than in the left and is
bilateral in 38% of cases {2598}. Recent
reports suggest an even higher frequency
of bilateral involvement {2850}.
Clinical features
Signs and symptoms
The usual patient with a gonadoblastoma
is a phenotypic female who is frequently
virilized {2605}. A minority may present
as phenotypic males with vary i n g
degrees of feminization.
The clinical presentation of a patient with
a gonadoblastoma can vary considerably
depending upon whether or not a
tumour mass is present, on the nature of
the underlying abnormal gonads, on the
development of secondary sex organs
and the occasional secretion of steroid
hormones {2598}. A patient with pure
gonadal dysgenesis may present with a
failure to develop secondary sex organs
and characteristics at puberty but has a
n o rmal height, and other congenital
anomalies are absent. Those with Turner
s y n d rome have sexual immaturity, a
height of less than 150 cm and one or
m o re congenital anomalies including
neonatal lymphedema, web neck, prognathism,
shield-shaped chest, widely
spaced nipples, cubitus valgus, congenital
nevi, coarctation of the aorta, renal
anomalies, short fifth metacarpal bones
and others {2598}. If a germ cell malignancy
develops in the dysgenetic
gonad, the patient may present with
lower abdominal or pelvic pain.
Macroscopy
Pure gonadoblastoma varies from a histological
lesion to 8 cm, and most
tumours are small, measuring only a few
cm {2598,2849,2850}. When a
gonadoblastoma is overgrown by dysgerminoma
or other neoplastic germ cell
elements, much larger tumours are
encountered. The macroscopic appearance
of gonadoblastoma varies depending
on the presence of hyalinization and
calcification and on the overgrowth by
other malignant germ cell elements.
Fig. 2.110 Gonadoblastoma. The tumour consists of cellular nests(germ cells and sex cord derivatives) surrounded
by connective tissue stroma. The sex cord derivatives form a coronal pattern along the periphery
of the nests and also surround small round spaces containing hyaline material. A mixture of cells is present
in the centre of the nests.
Histopathology
H i s t o l o g i c a l l y, gonadoblastoma is a
tumour composed of two main cell types,
germ cells which are similar to those
present in dysgerminoma or seminoma
and sex cord derivatives re s e m b l i n g
immature Sertoli or granulosa cells. The
stroma in addition may contain collections
of luteinized or Leydig-like cells
devoid of Reinke crystals. The tumour is
arranged in collections of cellular nests
surrounded by connective tissue stroma.
The nests are solid, usually small, oval or
round, but occasionally may be larger or
elongated. The cellular nests are composed
of germ cells and sex cord deriv-
176 Tumours of the ovary and peritoneum