Transcript Tumors of the testis

Tumors of the testis
KVB
Important facts about testicular
tumors
• Uncommon, incidence: 5/100,000 men
• <1% of all malignancies in men
• Peak: 30-40 years, rare in prepubertal
children & elderly
• >90% are of germ cell origin
• >90% are malignant
• Serum tumor markers found in 50% of
patients. Eg: AFP, hCG
Risk factors for testicular cancers
• Sex chromosome abnormalities: Germ
cell tumors occur at a rate of 25% in
dysgenetic gonads,intersexes,
hermaphrodites & pseudohermaphrodites.
• Cryptorchidism: 10-fold increase in
incidence of testicular germ cell tumors.
Histogenesis of testicular germ cell
tumors
• Originate from intratubular germ cells that
have undergone malignant transformation
• First occurs as carcinoma-in-situ or
intratubular testicular germ cell
neoplasia (ITTGCN)
• Malignant cells have enlarged,
hyperchromatic nuclei & cytoplasm filled
with glycogen
• ITTGCN is usually diagnosed incidentally
during biopsy for infertility workup
Clinical classification of testicular
tumors
• Seminomas (40%)
• Nonseminomatous germ cell tumors
(NSGCT) (40%)
• 15% of tumors have both seminomatous &
nonseminomatous elements.
• Nonseminomatous elements are more
malignant, therefore such tumors are
clinically treated as NSGCT.
Seminoma
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Most common type of germinal tumor (50%)
Most patients are 25-45 years of age
Presents as a scrotal mass
Most tumors diagnosed early
No serologic tumor markers for seminoma
Treatment: surgery, radiation therapy &
chemotherapy
• Cure rate>90%
Gross features of seminoma:
• Produces bulky masses, sometimes10x
normal testis
• Homogenous, grey-white, lobulated cutsurface, usually devoid of hemorrhage &
necrosis
• Replaces entire testis in half of cases
Histologic features of seminoma:
• Composed of single cell type
• Tumor cells have clear cytoplasm, filled
with glycogen
• Tumor cells are arranged in lobules which
are surrounded by fibrous stroma
• The fibrous septa are infiltrated by
lymphocytes & plasma cells
• Metastases occur in paraaortic abdominal
lymph nodes
Spermatocytic seminoma
• Rare but distinct clinicopathologic variant
of seminoma that occurs only in the
descended testes of elderly men and
forming about 5% of seminomas
• The tumor is bilateral in about 6% of cases
compared to about 2% in classic
seminoma
Morphology of spermatocytic
seminoma:
• Gross:The tumor tends to be poorly
demarcated, usually soft with a gelatinous or
mucoid appearance. Cystic areas, especially in
the center, are common but hemorrhage or
necrosis is almost always absent.
• Micro: Three populations of tumor cells,
separated according to size, are seen: 1) small
cells that superficially resemble lymphocytes, 2)
intermediate or medium-sized cells, the
commonest cell type, have round nuclei and
finely granular chromatic pattern, and 3) large or
giant cells.
Biological behaviour of
spermatocytic seminoma:
• Spermatocytic seminoma is an extremely
indolent tumor with rather limited
malignant potential and rarely if ever
metastasizes.
Embryonal carcinoma
• This subtype of GCTs represents the most
primitive form of the NSGCTs.
• It accounts for about 15 to 35% of
testicular GCTs.
• Grossly, the tumors
are large, often
hemorrhagic and
necrotic producing a
variegated cut
surface.
• Histologically, they are extremely
pleomorphic and show a variety of
patterns forming glands, tubules, and even
primitive embryo-like structures.
• Many mitotic figures are present.
Embryonal carcinoma: Sheets of cells with large,
hyperchromatic nuclei, prominent nucleoli and poorly-defined
cell borders
• Embryonal carcinoma metastasizes early
and widely via both lymphatic and
hematogenous routes
Yolk Sac Tumor (Endodermal
Sinus Tumor)
• Testicular yolk sac tumors occur in two forms:
either as a pure form in young children or as a
focal differentiation within other NSGCTs, mainly
embryonal carcinoma, in adults.
• Pure YST of the adult testis is rare.
• It is noted for its resemblance to rat fetal yolk
sac and the presence of microscopically
distinctive structures known as Schiller-Duval
bodies.
Pathologic features of yolk sac
tumor
• Gross: The cut
surface is gray-white
and may be cystic.
Microscopic features of yolk sac
tumor
• Microscopically, the
tumor shows a variety
of patterns, the
commonest of which
is a loose meshwork
of small spaces and
cysts (producing a
sieve-like
appearance) lined by
either flattened cells
or vacuolated cells
Serum markers in yolk sac tumor
(YST)
• YST is almost invariably associated with
production of large amounts of alphafetoprotein (AFP) and also alpha-1
antitrypsin (a -1AT).
• AFP may be followed as a marker of
disease progression in the patient's serum.
Teratoma
• A tumor typically composed of several
tissues representing two or more germinal
layers
• Teratomas are further subdivided into
mature, immature and teratoma with
malignant transformation
Mature teratoma showing cysts lined by mucous epithelium (left) and
keratinizing squamous epithelium (right).
Immature teratoma with primitive brain tissue (upper left corner) and welldifferentiated glands (lower half).
Choriocarcinoma
• This is a highly malignant neoplasm that is
usually widely disseminated and frequently
fatal.
• In this form of testicular GST the cells
differentiate in the direction of
trophoblastic (placental) tissue
• The tumor typically presents in adolescent
or young adults with widespread disease,
Choriocarcinoma: large, hemorrhagic, necrotic tumor.
Microscopically, the tumor is composed of two types of cells:
Syncytiotrophoblasts, large multinucleate cells with abundant vacuolated
cytoplasm containing hCG and Cytotrophoblasts, polygonal cells with
distinct cell borders and single nuclei, which grow in clusters and are
surrounded by the syncytiotrophoblasts
Sex cord-stromal tumors of the
testis
Leydig cell tumor key facts:
• Can develop at any age from infancy to
old age
• Most are benign, some are malignant
• Most tumors are hormonally active, but
some are inactive
• May secrete androgens or estrogens
-Androgen excess: Premature puberty &
macrogenitosomia
-Estrogen excess: Gynecomastia in adult males
Sertoli cell tumor
• These tumors are more rare than Leydig
cell tumors.
• They elaborate androgens or estrogens.
• Occasionally, they cause gynecomastia
but sexual precocity is infrequent.
Important Qs
1. Investigation of male infertility
2. Classification of testicular tumors, both
clinical as well as pathologic
3. Seminoma in detail
4. All germ cell tumors, in brief
5. Functional tumors of the testis
6. Serum markers for testicular tumors