Testicle pathology refers to lesions, disorders, and tumors that affect the testes.
Testicle pathology includes:
- Cryptorchidism
- Orchitis
- Testicular torsion
- Varicocele
- Hydrocele
- Testicular tumors (germ cell tumors and sex cord tumors)
- Lymphoma
Cryptorchidism
Cryptorchidism refers to testicle’s inability to enter the scrotal sac.
As the fetus matures, the testicles typically descend into the scrotal sac from where they ordinarily develop in the abdomen.
Cryptorchidism is the most prevalent congenital male reproductive abnormalities.
One percent of male babies are born with cryptorchidism.
Most cases resolve on their own, but if not, orchiopexy is done before the age of two.
Complications of cryptorchidism include:
- Testicular atrophy
- Infertility
- Increased risk of seminoma
Cryptorchidism. Different forms of cryptorchidism, depending on the position of the undescended testicle. Sometimes the retractile testicle is added Lamiot - Not altered. CC BY-SA 3.0
Orchitis
Orchitis is inflammation of the testicle.
Causes of orchitis include:
- Chlamydia trachomatis (serotypes D-K)
- Neisseria gonorrhoeae
Orchitis is visible in young adults.
Orchitis increase the risk of sterility.
Micro-organisms associated with orchitis include:
- Escherichia coli
- Pseudomonas
Teenage boys with the mumps virus have a higher risk of being infertile.
Children under the age of 10-years-old are typically not affected by testicular inflammation.
Granulomas in the seminiferous tubules are a defining feature of autoimmune orchitis.
Orchitis. Doppler ultrasound of the scrotum, in the axial plane, showing orchitis (as part of epididymo-orchitis) as hypoechogenic and slightly heterogenic left testicular tissue (right in image), with an increased blood flow. There is also swelling of peritesticular tissue. Mikael Häggström, M.D. Not altered. CC0
Testicular Torsion
Testicular torsion is caused by spermatic cord twisting.
Testicular torsion causes narrow-walled veins to become blocked, leading to congestion and hemorrhagic infarction.
Testicular torsion typically results due to testes’ congenital inability to adhere to the scrotum’s inner line of the scrotum.
Testicular torsion should be suspected in adolescent males that have abrupt testicular pain and a lack of cremasteric reflex.
Testes. Drawing of testis. Not altered. CC Public Domain
Varicocele
Varicocele is the dilation of the spermatic vein because of impaired drainage.
Varicocele presents as a “bag of worms” like scrotal enlargement.
Varicoceles are typically left sided.
The left testicular vein drains into the left renal vein.
Varicoceles may be seen in the setting of left-sided renal cell carcinoma.
Varicocele. Wound after microsurgical varicocelectomy Sagitarius12x - Not altered. CC BY-SA 4.0
Hydrocele
Hydrocele is a fluid collection within the tunica vaginalis.
The inside surface of the scrotum and the testicle are both protected by the membrane known as tunica vaginalis.
Hydroceles are associated with blocked lymphatic drainage or inadequate closure of the processus vaginalis causing communication with the peritoneal cavity.
Hydrocele presents as a transilluminable scrotal enlargement.
Hydrocele. Communicating hydrocele, caused by the failure of the processus vaginalis closure. Nevit Dilmen (talk) - Not altered. CC BY-SA 3.0
Testicular Tumors
Testicular tumors originate from sperm or sex cord stroma.
Testicular tumors present as a firm, painless testicular mass which cannot be transilluminated.
Testicular tumors are generally not biopsied because of risk of seeding the scrotum.
Malignant germ cell tumors represent the majority of testicular cancers.
Testicular tumors are removed through radical orchiectomy.
Germ Cell Tumors. Germ cells tumors constitute a vast majority of the incidences of testicular tumors. Mikael Häggström, M.D. Not altered. CC0
Germ Cell Tumors
Germ cell tumors are the most prevalent type of testicular tumor (> 95 percent of cases).
Germ cell tumors typically occur between the ages of 15-to-45 years of age.
Risk factors for germ cell tumors include:
- Cryptorchidism
- Klinefelter syndrome
Germ cell tumors are classified into seminoma and nonseminoma types.
Seminomas (which account for 55 percent of cases) have a great prognosis, late metastasis, and a high radiation treatment response rate.
Large cells with transparent cytoplasm and central nuclei (like spermatogonia) make up the malignant tumor known as a seminoma, which develops as a homogeneous mass without bleeding or necrosis.
Nonseminomas (which account for 45 percent of cases) respond to therapy differently and frequently metastasis quickly.
Nonseminomas include:
- Testicular dysgerminoma
- Yolk sac tumor
- Mixed germ cell tumor
- Teratoma
Testicular dysgerminoma
A cancerous tumor made up of immature, primitive cells that could one day develop into glands is called an embryonic carcinoma.
Beta-hCG may appear in unusual instances.
Treatment for testicular dysgerminoma is radiation therapy.
Testicular dysgerminoma has a good prognosis if treated appropriately.
Yolk sac tumor
Yolk sac tumor is a malignant tumor comprising syncytiotrophoblasts and cytotrophoblasts (placenta-like tissue, but villi are absent) is known as choriocarcinoma.
Yolk sac tumor is the most typical testicular tumor in kids.
The alpha-fetoprotein (AFP) is typically high in patients with a yolk sac tumor.
Histology of yolk sac tumors classically show Schiller-Duval bodies.
Teratoma
Mature fetal tissue generated from two or three embryonic layers makes up teratomas, which are tumors.
Teratomas are considered malignant in men (as opposed to women).
Mixed germ cell tumors
Germ cell tumors are typically mixed.
Prognosis is based on the worst component.
Animal models of TGCT and correlation to human histologic subtypes.TGCTs appear to arise from embryonic germ cells (EGC) in infants and young children (“type I”) or in adolescents and young adults (“type II”) [4]. (For clarity, the presumed carcinoma in situ precursor cell for type II tumours is omitted). These are further sub-divided by histologic subtype: yolk sac tumour (YST), teratoma (Ter), seminoma, choriocarcinoma (CC), embryonal carcinoma (EC). Current animal models of TGCT correlate to type I teratomas (129/Sv mice) and type II seminomas (bmpr1bb or lrrc50 fish). Important genetic aberrations in human tumours are listed below. Mouse teratoma photo courtesy of Dr. David Zarkower. A big catch for germ cell tumour research. Chen KS, Amatruda JF - PLoS genetics (2013). Not Altered. CC.
Sex Cord Stromal Tumors
Sex cord stromal tumors are usually benign tumors that resemble the cord-stromal tissues of the testis.
The types of sex cord stromal tumors include:
- Leydig cell tumors
- Sertoli cell tumors
Typically, Leydig cell tumors generate hormones, which can lead to gynecomastia in adults or premature puberty in children.
Characteristic Reinke crystals may be seen in histology of sex cord stroma tumors.
Sertoli cell tumor consists of tubules and is typically clinically silent.
Sex Cord Stromal Tumors. Low magnification micrograph of a Sertoli cell tumour. H&E stain. Nephron - Not altered. CC BY-SA 3.0
Lymphoma
Lymphomas are the most typical reason for a testicular mass in a male over 60-years-old.
Testicular involvement by lymphoma is usually bilateral.
Diffuse large B-cell (DLBCL) type is the most common type of lymphoma to involve the testes.
Mantle Cell Lymphoma. Lymph node with mantle cell lymphoma (low power view, H&E) Gabriel Caponetti - Not altered. CC BY-SA 3.0
