Diseases of the testis and penis Flashcards
Overview of progression of spermatogenesis
primary spermatocytes (diploid) → secondary spermatocytes (haploid) → spermatids → spermatozoa
Spermiogenesis
process of cytodifferentiation by which spermatids become spermatozoa
Leydig cells
Produce testosterone in response to pituitary luteinizing hormone
Cryptorchidism
Congenital maldescent of one (75% of cases) or both (25%) testes
Vast majority are idiopathic (? hormonal or mechanical factors)
Contralateral testes may also regress and result in infertility
Undescended testes have 10-40 fold increased risk of developing cancer
- Risk increased in contralateral testis as well (to less extent)
- Surgery may not reduce risk
When does histologic evidence of atrophy begin with cryptorchidism and what does that look like?
Begins as early as 2 years of age
- Arrest in germ cell development
- Thickening of basement membrane and hyperplasia of Leydig cells
- Eventual “hyaline” replacement
Other causes of testicular atrophy (not due to cryptorchidism)
A. Atherosclerosis B. Inflammation C. Malnutrition D. Hypopituitarism E. Hormone therapy (prostate cancer) F. Klinefelter’s Syndrome
Causes of male infertility
A. Congenital abnormalities (e.g. cryptorchidism, immotile cilia syndrome, anorchia, absent vas)
B. Acquired abnormalities
- Torsion and infarction
- traumatic/mechanical or vascular - Varicocele – dilatation and tortuosity of veins in pampiniform plexus
- Obstruction
- Inflammation
C. Hormonal abnormalities (FSH, LH or GnRH deficiencies)
D. Klinefelter’s Syndrome (Sclerosing tubular degeneration)
- 47 XXY most common
- Tubular sclerosis with absence of elastic fibers
- Leydig cell nodules
- Elevated FSH/LH and decreased testosterone
Inflammatory diseases of testis / epididymis
Nonspecific epididymitis and orchitis
Mumps orchitis
Tuberculus orchitis
Syphilis
Nonspecific epididymitis and orchitis
Inflammatory disease of testis/epididymis
Usually due to direct extension from urinary tract (vas deferens or lymphatics) and tends to effect epididymis first with subsequent orchitis
In children – usually associated with urinary tract malformations (gm neg rods)
In sexually active adults – Chlamydia trachomatis, N. gonorrhoeae
Elderly – enterobacteria
Acute inflammation – may develop abscesses
Mumps orchitis
Inflammatory disease of testis/epididymis
Can occur in pubertal or adult males who acquire mumps (30%)
Usually subsequent to parotid involvement
Unilateral in 70% of cases
Mononuclear inflammatory infiltrate with interstitial edema +/- neutrophils
Infertility uncommon
Tuberculus orchitis
Inflammatory disease of testis/epididymis
Almost always begins in epididymis with spread to testes
Usually part of systemic disease
Caseating granulomas
Syphilis
Inflammatory disease of testis/epididymis
Almost always involves testes first
Congenital or acquired
Diffuse mononuclear interstitial inflammation rich in plasma cells
Obliterative endarteritis
+/- gummas
What is the most common kind of testicular tumor?
Germ cell tumor (95%)
Germ cell tumors
Malignant germ cells may reflect spermatocytic differentation (seminoma) or totipotential cells (embryonal carcinomas) which can then transcend along various lines of intraembryonic (teratoma) or extraembryonic
(choriocarcinoma, yolk sac tumor) differentiation
Can form pure tumor types (“pure” seminoma or embryonal carcinoma) or mixtures of tumor types
Metastases can be of different type than primary
Tend to occur in young men (15-35 years) – painless testicular enlargement
Predisposing factors: cryptorchidism, genetic factors, testicular dysgenesis
Types of Germ cell tumors
Seminoma Spermatocytic seminoma Embryonal carcinoma Yolk sac tumor Choriocarcinoma Teratoma Mixed GCT’s