Week 1 - Male Genitourinary System Flashcards
Renal Pelvis and Ureter Epithelium
Renal pelvis
- urothelium specialised epithelium 3-5 layers thick
- lamina propria, highly vascular with no muscularis mucosa
Ureter
- urothelium specialised epithelium, 5-7 layers thick
- muscularis propria is composed of interlacing bundles of smooth muscle
Disease of the Urinary Tract
Symptoms:
- haematuria
- loin pain
- fever
- difficulty urinating
- lower back pain etc.
Causes:
- congenital or acquired
- tobacco use/smoking
- exposure to chemicals
- recurrent UTI’s
Clinical Investigations:
- urinalysis
- urine cytology
- pyelography/ureteroscopy
Tissue Sampling In Various Cases
Biopsies and transurethral resections for bladder tumours
- processed as small biopsies (TURBT)
Radical or partial cystectomy, or segmental ureterectomy for bx confirmed invasive HGUC
- performed on proximal or mid ureter
Radical or partial nephroureterectomy - minimally invasive procedure to remove renal pelvis, kidney, ureter and bladder cuff.
Non-Neoplastic Conditions in the Bladder
Bacterial cystitis - most common cause usually due to coliform bacteria (E. Coli) ascending the urethra
Malakoplakia - caused by a defect in the host macrophage response to bacterial infections, can infect any genitourinary system M or F
Polypoidal cystitis - non-specific inflammation of the bladder mucosa
Nephrogenic adenoma - usually associated with previous surgical intervention, small polypoid lesions of metaplastic origin
Interstitial cystitis/painful bladder - can be seen in patients with hx of fibromyalgia, IBS
Bladder stones/lithiasis - common in men, associated with bladder outlet obstruction.
Diverticulae - often in elderly men, due to increased luminal pressure secondary to prostate enlargement resulting in obstruction
Common Benign Tumours of the Urogenital Tract
Urothelial papillomas
Keratinising sq metaplasia - associated with chronic irritation i.e. catheters, stones, parasitic infections
Urothelial dysplasia - usually a flat lesion with cytological and architectural abnormalities, short of that for malignancy.
Urothelial CIS - rarely occurs on it’s own, linked with area of invasion
- lesions are flat with features of high grade abnormality with no definite evidence of invasion to surrounding stroma
Urothelial Carcinoma
Men >70 years are 3x more likely to be diagnosed than women
UC or TCC accounts for >90% of primary bladder tumours
Diagnosis is usually confirmed on biopsy, which commonly shows a papillary or solid growth pattern
Urine cytology is useful in CIS and high grade bladder lesions
FISH is considerably more sensitive and only slightly less specific than cytology
Prognosis is very important and depth of invasion in bladder wall determines stage and prognosis
- 70% 5 yr survival rate for stages pTa and pT1 (MM) and 50% for pT2
The Urethra
In the male, the urethra is ~15-20cm in length and is divided into 3 sections:
1. Prostatic urethra
- 3-4cm in length
- extends through the prostate gland and is lined by urothelium
2. Membranous urethra
- a short segment that passes through the external sphincter of striated muscle
- lined by stratified columnar and pseudostratified columnar epithelium
3. Penile urethra
- ~15cm in length
- enclosed within erectile tissue of the penis
- lined by stratified columnar and pseudostratified columnar epithelium, with stratified squamous epithelium distally.
Periurethral glands - bulbourethral or Cowper glands, Glands of Littre in the penile part
Non-Neoplastic Urethral Condtions
Urethritis - usually an STD due to Chlamydia or N. Gonorrhoea
Polypoid urethritis - polypoid cystitis where see oedema with a mixed inflammatory pattern
Benign stricture - as a result from previous trauma or inflammation e.g. catheterisation
Urethral polyps - small papillary-like growths seen in the prostatic urethra of adult males
- usually asymptomatic but may cause haematuria
Testes
Pair of pear-shaped organs that are found in the scrotum
- each of which are suspended within an elongated pouch continuous with the anterior abdominal wall that projects into the scrotum
- the testis are connected by the spermatic cords to the abdominal wall and tethered to the scrotum by scrotal ligaments
Most testicular lesions are non-neoplastic, such as;
- mumps, orchitis, torsion
- presentation of testicular lesions may accompany a hydrocoele, which is an accumulation of fluid surrounding the testis
Undescended Testes
Also known as Cryptorchidism
During fetal development, the testis is undescended in ~5% of boys, although this may rectify itself by the child’s 1st bday
An undescended testes usually situated in the inguinal canal in the body cavity
Causes spermatogenic activity to be hindered
Hydrocoele
Most common cause of scrotal swelling, an accumulation of serous fluid within the tunica vaginalis of the testes
2 types:
1. Congenital hydrocoele - found in the first few weeks of birth
2. Secondary hydrocoele - associated with an underlying lesion of the testes or epididymis
Testicular Torsion
Results in sudden severe pain on one side of the scrotum
Usually testes should be the same size, but if one becomes larger than the other this can be a cause for concern.
Testicular torsion can occur when blood flow to the testes is inhibited, resulting in severe pain
If blood supply to the testes is not restored within 6 hours, the testicle could become atrophied
Treatment: spermatic cord needs to be untwisted to restore blood flow
Orchitis
Inflammatory process of the testis
It can correlate with inflammation of the epididymis called epididymo-orchitis, caused by ascending infection
Most common form of infection is:
- gram-negative bacterial orchitis, 2◦ to UTI
- infection may manifest as an abscess or suppuration and fibrosis
- syphilis and mumps can also result in orchitis
What is the consistent finding of Testicular Tumours?
An additional fragment of chromosome 12 is identified
Seminoma
Solid, rubbery-firm, lumpy masses
Tumour tissue is well demarcated compared to normal tissue, which may appear compressed, atrophic or fibrotic
On cross section, seminoma can appear lobulated and homogenously tan or gray/yellow in appearance
Focal areas of haemorrhage, necrosis may be seen in larger tumours
Commonly localised to testes
Histology of Seminoma
Monotonous sheets, lobular arrangements with a fibrous septae
Cells are pleomorphic with a pale (glycogen filled) eosinophilic cytoplasm
Cell membranes are well defined with distinct cell boundaries
Nuclei are polygonal, with an appearance of being squared off, contain one or more prominent nucleoli
Lymphocytic infiltrate of predominantly T lymphocytes with plasma cells sometimes seen
Occasionally, giant cells or multinucleated syncytiotrophoblasts can be seen in 20% of tumours, these can produce hCG
Cytology of Seminoma
Usually observed via ROSE FNA of testicular mass under US
See discohesive population of large cells with a moderate amount of cytoplasm
Round, irregular nuclei, with prominent multiple nucleoli
Most striking feature is the background of the shows a ‘tigroid’ (stripped or spotted) appearance admixed with small, mature lymphocytes
Vas Deferens
3 thick muscular layers
Connects the tail of the epididymis to the ejaculatory duct at the prostate
The surface mucosa of the VD is lined by a columnar epithelium
Transports spermatozoa to the ejaculatory duct
Penis Histology
Surface epithelium is thin and NKSSE in uncircumcised men, KSSE in those circumcised
LP is loose CT ~1-4mm thick, and separates from the corpus spongiosum
The outer capsule is a dense CT, the tunica albuginea this terminates near the glans, and separates the corpus cavernosa from the spongiosum
Rich network of lymphatic vessels in the glans and corpora cavernosa along the dorsal vein eventually draining into the superficial inguinal LNds
Benign Prostatic Hyperplasia
Extremely common, androgen dependent disorder caused by hormonal imbalance affecting the stromal and epithelial component
Patient may experience urinary obstructive symptoms, prostate enlargement
Often develops in the transition and periurethral zones
Gross examination shows multinodularity, grey to yellow, usually with
compression of the urethra
Histology, see increase in both the prostatic and stromal components, with increase in the stromal nodules with more smooth muscle seen
