Chapter 14 - Testis Flashcards
What are the indications for orchiectomy?
Tumor
Torsion
Cryptorchidism
At what age range do most testicular tumors occur?
Age 20-40
Describe the normal morphology of the testis.
A tightly packed collection of tubules lined with spindly, radially arranged sertoli cells and spermatogonia.
Where does spermatic maturation occur?
Where do sperm leave the testis?
Maturation is completed near the lumen of the seminiferous tubules.
Sperm leave the testis via the rete testis.
Describe the morphologic appearance of the epididymis.
Series of tubules with columnar, pseudostratified ciliated epithelium
Describe the morphologic appearance of a cryptorchid testis.
Small atrophic seminiferous tubules with fibrosis and widened interstitial spaces.
What is “vanishing testis syndrome”?
When an undescended testis is surgically removed to reveal nothing but fibrosis and dystrophic calcification attached to an epididymal remnant.
What are some possible biopsy findings for infertility?
Aplasia (or “sertoli-only” syndrome)
Hypospermatogenesis
Maturation arrest
“End-stage testis” (sclerosis/atrophy, no tubules)
Normal spermatognesis (implies distal obstruction)
Name four types of germ cell tumor.
Which is most common?
Seminoma
Embryonal carcinoma
Yolk sac tumor
Choriocarcinoma
*Mixed is most common*
What testicular tumors are most common in young children? Young adults? Older adults?
Young children: Yolk sac tumor, teratoma
Young adults: Seminoma, embryonal carcinoma, choriocarcinoma, teratoma
Older adults: Spermatocytic seminoma, lymphoma, sex cord stromal tumors
Say a patient has evidence of a germ cell testicular tumor, but resection reveals a fibrotic scar. How is this explained?
Germ cell tumors can regress, leaving behind a fibrotic scar. They could still have metastasized, however.
Describe the morphologic features of seminoma.
Array of large, round, coarse nuclei in a network of delicate cell membranes
1-2 prominent central nucleoli
Delicate fibrovascular septae
Associated inflammation and intratubular germ cell neoplasia
What is the appearance and significance of intratubular germ cell neoplasia?
Analogous to testicular carcinoma in situ. Can appear subtle, with a few big cells in the tubule or with pagetoid spread. Often found in association with a full-blowm germ cell tumor.
What morphologic features can help distinguish intratubular germ cell neoplasia from spermatogonia?
Cytoplasm is more clear
Chromatin is coarser & chunkier
Nuclear membrane is irregular, with prominent nucleolus
Little to no spermatic maturation
c-Kit, OCT3/4, PLAP positive.
What is spermatocytic seminoma? What is unique about it?
A low-grade, indolent seminoma in older men. It lacks inflammation and PLAP positivity, and is not found in mixed tumors nor is it associated with IGCN.
Describe the morphologic appearance of an embryonal carcinoma.
“The ugly one”, with very pleomorphic cells. Looks epithelioid, and stians with keratins. Architecture is solid, glandular, or papillary.
Describe the morphologic appearance of yolk sac tumor.
Has many forms, especially microcystic and reticular.
Pathognomonic finding: Schiller-Duval body, a glomeruloid form.
Nuclei are smaller and more regular than embryonal carcinoma but not as regular as seminoma. Somewhat hypocellular and myxoid.
Describe the morphologic appearance of choriocarcinoma.
Two cell types (cytotrophoblast and syncytiotrophoblast), lots of blood. Very invasive.
What are the components of teratoma?
What is the most important consideration in men?
Elements of primitive germ layers (ectoderm, mesoderm, endoderm), and can develop tumors
The age of the patient; they are always benign in prepubertal boys and are malignant in postpubertal or adult men.
Describe the morphologic appearance of sertoli tumors.
Describe the morphologic appearance of leydig tumors.
Sertoli tumor: Collection of primitive tubules lined with spindly cells and oval nuclei.
Laydig tumor: Tumor of oncocytic pink cells with very round nuclei
What percentage of sex cord stromal testicular tumors are malignant? How do they appear?
10%
Usual criteria apply (atypia, mitotic rate, necrosis, vascular or extratesticular invasion)
What should be on your differential for a lesion that resembles a less homogeneous seminoma with vesicular chormatin and large nucleoli?
Diffuse large B-cell lymphoma.
Where else can germ cell tumors be located, beyond the testis?
Mainly in the midline (sacrum, mediastinum, sella turcica, pineal gland).
What term is given to a germ cell tumor in the brain?
Germinoma
Normal seminiferous tubule
- Large spermatogonia with clear cytoplasm
- Spermatids
- Plump pink leydig cells in the interstitium
Rete testis
(slit-like spaces with cuboidal epithelium)
Normal epididymis
(columnar epithelium with cilia)
Cryptorchidism (infant)
Arrow: Large, dark spermatogonia
Sertoli-only syndrome; no germ cells are visible
Seminoma, classic type
Arrow: Fibrovascular septae with lymphocytes
Circle: Mitoses
Arrowhead: Distinct nuclear membranes with prominent nucleoli
Intratubular germ cell neoplasia
- Large cells with clear halos of cytoplasm
- Hyperchromatic nuclei
- Normal adjacent endothelium
Embryonal carcinoma
(large epithelioid pleomorphic cells in sheets)
Arrow: Dark nuclear membranes, prominent nucleoli
Yolk sac tumor, microcystic pattern
(relatively low-grade, with cuboidal cells with pink cytoplasm)
Leydig cell tumor
(reminiscent of oncocytoma)
Sertoli cell tumor
(tumor attempts to recapitulate the seminferous tubules, with hyalinized stroma)
Diffuse large B-cell lymphoma
(sheets of discohesive tumor cells with chunky nuclear chromatin)
