Male genital system Flashcards
Describe the anatomy and histology of the prostate gland
- ejaculatory ducts
- central zone
- transition zone
- peripheral zones
- apex
- Functions: secretion of important components of seminal fluid - semen liquefaction
Macroscopy:
* Apex and base
* Macroscopically difficult to see any cancers
* Transverse section shows stroma and urethra
* Prostate divided into different zones - depending on where tumour is, may or may not see obstructive symptoms
- Histology
- Fibromuscular stroma and glandular layer
- Glands are lined by 2 layers of cells:
- Basal cells at periphery - cancer causes loss of basal layer
- Epithelial cells on luminal surface
Note: Corpora amylase: calcified concretions within the glands that are more characteristic of benign neoplasms
Describe non-neoplastic lesions of the prostate
-
Infection (reduced sensitivity of FF tissues for testing)
- Acute and chronic bacterial prostatitis: acute prostatitis shows neutrophil infiltration, chronic prostatitis shows numerous dark blue lymphocytes in stroma between glands. All galnds are surrounded by 2 cell layers
- Tuberculous prostatitis: granulomatous necrotising
- Inflammation
- Non-specific chronic prostatitis
- Granulomatous prostatitis – secondary to BCG treatment
- Xanthogranulomatous prostatitis
-
Deposits
- calciuli
- amyloid
List neoplastic lesions of prostate gland
- Neoplastic lesions
- Epithelial (glands)
- Benign: adenosine
- Malignant: acinar adenocarcinoma
- Epithelial (glands)
- Mesenchymal (stroma)
- Benign: leiomyoma
- Malignant: Leiomyosarcoma and Stromal sarcoma - Mixed epithelial and mesenchymal
- Benign: Benign Prostatic Hyperplasia (BAH)
- Malignant: Epithelial stromal sarcoma AND Invasion from nearby organs: bladder, urethra, rectum
Describe the presentation and risk factors of BPH
Presentation
* Lower urinary tract symptoms (LUTS) due to voiding difficulties
* Haematuria
* Recurrent UTI
* Bladder calculi
* Acute urinary retention
* Urinary tract obstruction ± renal failure
Risk factors
* Acquired
* Age (50% by 60, 90% by 85)
* Obesity/metabolic syndrome
* Sedentary lifestyle
* Diet
* Protective: Moderate ETOH consumption, citrus juice, lycopene, carotenoids, vitamin A
* Risk increases: coffee, vitamin C supplements
* Genetic
* Ethnicity (African descent = worse disease at younger age)
* Poorly understood genetic factors, but familial clustering seen
Describe the pathophysiology of BPH
- Very common affecting most older men (80% of men 70+)
- Increase in prostate size due to hyperplasia of glandular and stormy tissue
- Testosterone and DHT-driven disease
- 5α reductase (released by stromal cells) converts testosterone to potent DHT (x10 potency)
- Prostate enlargement contributes to urinary dysfunction
- Obstructive urinary symptoms
- Progressive urodynamic dysfunction with alterations in smooth muscle tone
Describe the macroscopy and microscopy of BPH
Macroscopy
* Enlarged prostate
* Hyperplastic nodules of varying sizes
* Distortion/compression/elongation of prostatic urethra due to nodules
Microscopy
* Nodular transformation of prostatic parenchyma
* Nodules composed of:
* Increased numbers of glandular structures (bilayer: inner liminal and outer basal layer)
* Expanded fibromuscular stroma with fine vascularity
* Glands still lined by 2 layers of cells (epithelial and basal)
Describe IHC, complications and treatment of BPH
IHC
* Antibodies targeted towards basal cells (high molecular weight cytokeratins) - all glands surrounded by immunostain
Complications
* Progressive symptoms, recurrence after surgery common
* Acute urinary retention
* Renal failure (complete obstruction: acute or chronic) * Recurrent UTI
* Bladder complications (stones, diverticuli)
Treatments
* Medical
* Androgen antagonists (e.g. 5HT inhibitors), smooth muscle relaxants (α blockers)
* Surgical
* TURP (transurethral resection of prostate to release urethral obstruction)
* Prostatectomy (Millin procedure)
Describe prostatic adenocarcinoma
- Elderly males
- May or may not present with symptoms
- Serum levels of Prostate Specific Antigen (PSA) may rise
Diagnosis:
Digital Rectal Examination and Ultrasonography help in diagnosis - Prostate Biopsy is needed for confirmation
Treatment options:
Radical prostatectomy or Radiotherapy or Hormone-specific therapy
- Histology:
- Cells show prominent nucleoli
- *Complete absence of basal cells
- back to back glands i.e. cribriform pattern
IHC:
- confirms absence of basal cells and suggests spread
Gleason Grading (architecture only)
* 1: Small, uniform, evenly-spaced glands
* 2: Glands slightly irregular with more intervening stroma
* 3: Irregular and irregularly-spaced glands
* 4: Gland fusion
* 5: No glands - solid nests, single cells, necrosis
Describe non-neoplastic lesions of the penis
-
Congenital: phimosiswhen the prepuce cannot be retracted over the corona, or balanitis xerotica obliterans: phimosis due to lichenoid inflammation
-
Inflammation: Condyloma accuminata, warty lesions caused by HPV 6 & 11:
- hyperkeratosis: thick keratin layer
- parakeratosis: nuclei stuck in keratin, showing abnormal maturation occurring
- acanthosis: thick epidermis
- koliocytes: shrivelled nuclei surrounded by pale halo
- Gross: papillary, fungating, wart-like, often multiple
-
Inflammation: Condyloma accuminata, warty lesions caused by HPV 6 & 11:
Describe neoplastic lesions of the penis
Squamous carcinoma
- *Risk factors: HPV 16 or 18, Rare if circumcision is done at birth, Most tumors arise from glans or inner foreskin near coronal sulcus as slow-growing
- Macroscopy: most tumours arise from glans or inner foreskin near coronal sulcus - slow growing
- Histology: infiltrating islands of squamous cells, keratin pearls deep in invading areas
- Cytology: hyper chromatic nuclei, pleomorphic, high NC ratio, mitoses visible*
Describe normal scrotum histology and discuss briefly pathology
- Normal histology
- Skin (epidermis with underlying stroma)
- Dartos muscle (unique to scrotum)
- Non-neoplastic:
- Hydrocele: collection of serous fluid in tunica vaginalis
Describe the histology of the testis
Testis: Normal histology
* Testis coated with fibrous tunica albuginea
* Parenchyma of testis with seminiferous tubules lined by developing sperm and sertoli cells
* Sertoli cells: stimulate and support spermatogenesis, form blood-testis barrier, secrete AMH in embryogenesis, secrete inhibin, activin, aromatase and other important factors
* Triangular shape with prominent nucleolus
* Leydig cells: in interstitium between tubules - secrete testosterone
* Large, round nuclei with prominent nucleoli and abundant granular cytoplasm with pink Reinke crystals
* Rete testis: comprises numerous inter-anatomising channels lined by specialised flattened cuboidal cells with a single motile cilium and microvilli
* Transmit sperm from seminiferous tubules to efferent ducts via cilia (sperm not yet motile)
* Fluid resorption via microvilli
* Epididymis: coiled tube up to 7m in length lined by simple columnar cells with stereo cilia (non-motile)
* Wall has contractile smooth muscle
* Connects rete to efferent ducts
* Reabsorb fluid
* Assist in sperm maturation (motility and fertility)
* Sperm storage up to 2.5 months
* Secretion of factors aiding maturation and suppressing motility until ejaculation
Describe non-neoplastic lesions of the testis
Cryptorchidism
- Undescended testes
- Shows atrophy and loss of normal seminiferous tubulues: hyalinsation around them appears pink
- absent Leydig cells in stroma
- Increase risk for malignancy
Torsion
- Occurs post-trauma or in undescended testis
- Very painful (emergency)
- Venous type infarction
- Orchidopexy
Briefly describe the two types of testicular tumours
SEMINOMA - radiosensitive
- Due to spermatocytic differentiation
- Typical/Anaplastic
- Spermatocytic
NON-SEMINOMATOUS- radioresistant:
Spread is early and via bloodstream, especially to lung
Tumours have trophoblastic, yolk sac and undifferentiated elements, have worse prognosis
- Intraembryonic differentiation
- teratoma: mature and immature
- Extraembryonic differentiation: yolk sac or choriocarcinoma
- Undifferentiated tumors: embryonal carcinoama
Describe seminoma
- Most common-50%. Usually 20 – 40 years old
- Painless, unilateral, bulky, testicular enlargement
- Gross appearance: Homogeneous, creamy white tumor, usually no hemorrhage or necrosis
Histology:
- Sheets of tightly packed cells with dark, central nuclei, prominent nucleolus, and clear cytoplasm
- Characteristic lymphoid infiltrate
- 50% or so of seminomas that contain syncytiotrophoblast (produced HCG)
- Spread via lymph nodes
