Urological histopathology Flashcards
- What are urinary calculi?
- What is the epidemiology?
- What can urinary calculi be made from?
- Crystal aggregates that form in the renal collecting ducts
•May be deposited anywhere in the urinary tract
2.
- Lifetime incidence 15%
- Males three times more likely to be affected than females
- Stones can be made of:
- Calcium Oxalate (Weddellite) – 75%
- Magnesium Ammonium Phosphate (Struvite) – 15%
- Uric Acid – 5%
Describe the common causes of calcium oxalate kidney stones
- Calcium oxalate stones are related to hypercalciuria
- Absorptive hypercalciuria – excessive calcium absorption from gut
- Renal hypercalciuria – impaired absorption of calcium in proximal renal tubule
- Hypercalcaemia – primary hyperparathyroidism
- Rare
- What are triple stones?
- What are they caused by?
- Magnesium ammonium phosphate stones are also known as ”triple stones”
2.
- Form as a consequence of infection with urease-producing organisms
- Proteus sp.
- Ammonia alkalinises urine – precipitation of magnesium ammonium phosphate salts follows
- Triple stones can become very large indeed
- “Staghorn Calculi”
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Triple stones
Describe the causes of uric acid urinary calculi
•Uric acid stones may form in patients with hyperuricaemia
- Gout
- Rapid cell turnover
- Most patients do not actually have hyperuricaemia or increased uric acid excretion in urine
- Believed to be due to tendency to produce slightly acidic urine
What are the complications of urinay calculi? For both large and small stones
•Small stones that stay in the kidney may be largely asymptomatic
- Otherwise detected during investigation of haematuria or recurrent urinary tract infection
•Small stones that drift out of the kidney may become impacted and cause colic
- Pelvi-ureteric junction, pelvic brim, vesico-ureteric junction
•Large stones tend to stay in the kidney
- Obstruction, risk of infection, chronic renal failure
- What is a papillary adenoma?
- What are the common genetic abnormalities?
- Benign epithelial kidney tumour composed of papillae and / or tubules
- By definition, 15mm or less in size
- Well-circumscribed
- Trisomy 7, Trisomy 17, Loss of Y chromosome
Frequent incidental finding in the nephrectomies on autopsy of CKD and acquired cystic renal disease patients
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Papillary adenoma
- What is a renal onocytoma?
- With what condition is it most commonly associated with?
- Benign epithelial kidney tumour composed of oncocytic cells
- Well-circumscribed
- Usually sporadic
- Birt-Hogg-Dube syndrome
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Renal oncocytoma
- What is an angiomyolipoma?
- With what condition is it seen?
- Benign mesenchymal kidney tumour composed of thick-walled blood vessels, smooth muscle and fat
- Derived from perivascular epithelioid cells
- Mostly sporadic
- Can be seen in tuberous sclerosis
Large tumors of bigger than 4cm present with flank pain, haemorrhage and shock
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Angiomyolipoma
- What is renal cell carcinoma?
- Epidemiology
- Risk factors
- Malignant epithelial kidney tumour
2.
- Accounts for 2% of cancers worldwide
- More common in developed countries
- 10 per 100,000 men, 3 per 100,000 women
- Risk factors include:
- Smoking
- Hypertension
- Obesity
- Long-Term Dialysis
- Genetic Syndromes – von Hippel Lindau
- What do half of cases of RCC present with?
- How else is RCC picked up?
- What are the various sub-types?
- Half of cases present with painless haematuria
2.
- Most of the remaining cases are detected incidentally on imaging
- Small proportion present with metastatic disease
- Various subtypes are recognised
- Clear Cell Renal Cell Carcinoma (70%)
- Papillary Renal Cell Carcinoma (15%)
- Chromophobe Renal Cell Carcinoma (5%)
- Remaining 10% are various rare subtypes
- What is clear cell renal carcinoma?
- How does it appear?
- What are the underlying genetics?
- Epithelial kidney tumour composed of nests of clear cells set in a delicate capillary vascular network
- Appears grossly as a golden yellow tumour with haemorrhagic areas
- Genetically shows loss of chromosome 3p
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Clear cell renal cell carcinoma
- What is papillary renal cell carcinoma?
- Underlying genetics
- How does it appear?
- Epithelial kidney tumour composed of papillae and / or tubules
* By definition, more than 15mm in size - Genetically shows trisomy 7, trisomy 17 and loss of Y chromosome
* Subdivided into two types based on morphology - Grossly appears as a fragile, friable brown tumour
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Papillary renal cell carcinoma
- What is Chromophobe renal cell carcinoma
- How does it appear?
- Epithelial kidney tumour composed of sheets of large cells that display distinct cell borders, reticular cytoplasm and a thick-walled vascular network
* Shows variable genetic aberrations - Grossly appears as a well-circumscribed solid brown tumour
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Chromophobe renal cell carcinoma
What are the staging and grading for Renal cell carcinoma?
- ISUP nuclear grade (1-4) applies to clear cell and papillary renal cell carcinoma
- TNM 8th Ed
- For clear cell renal cell carcinoma there is also a risk progression index
- Leibovich risk model (low risk, intermediate risk, high risk)
- What is a nephroblastoma?
- How does it present?
1.
- Also known as Wilm’s Tumour
- Malignant triphasic kidney tumour of childhood
- Blastema (small round blue cells)
- Epithelial
- Stromal
- Typically presents as an abdominal mass in children aged 2-5 years old
* 1 in 8,000 – second most common childhood malignancy
- What is a urothelial carcinoma?
- What are the risk factors?
1.
- Also known as Transitional Cell Carcinomas
- Group of malignant epithelial neoplasms arising in urothelial tract
- Bladder
- Renal Pelvis
- Ureters
- Very common:
- Smoking
- Aromatic amines
- What is the most common presentation of urothelial carcinoma?
- What are the three main subtypes?
- Haematuria
- Three main subtypes:
- Non-Invasive Papillary Urothelial Carcinoma
- Infiltrating Urothelial Carcinoma
- Flat Urothelial Carcinoma in-situ
- Describe non-invasive papillary urothelial carcinoma
- Appear as frond-like growths
- Divided into low grade and high grade (WHO 2004) based on nuclear atypia
- Low grade tumours have a low risk of progression to invasive disease (<5%)
- High grade tumours carry a higher risk of progression to invasive disease
- Unstable, carry a number of genetic aberrations including in RB and TP53
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Non-invasive Papillary Urothelial carcinoma
- What is infiltrating Urothelial carcinoma?
- What is treatment based on?
- Urothelial tumor displaying invasive behavior
- Treatment based on depth of invasion
- Lamina propria
- Muscularis propria
What does flat urothelial caricinoma in situ
- May be invisible or appear as a reddish area
- Flat urothelial lesion with unequivocal high grade features - high risk of progression
- What is benign prostatic hyperplasia?
- Epideimiology
- Aetiology
- Benign enlargement of prostate as a consequence of increase in cell number
2.
- Very common – symptomatic in 25% of men by age 80
- Histologically present in 90% of men by age 80
- Aetiology is not clear
- Increased oestrogen levels in blood, which rises with age, may induce androgen receptors and stimulate hyperplasia
- Treatment based on alpha blockers and 5⍺-reductase inhibitors as well as transurethral resection
How does BPH present?
Presents with “Lower Urinary Tract Symptoms”
- Frequency
- Nocturia
- Urgency
- Hesitancy
- Poor flow
- Terminal Dribbling
May also present with urinary tract infectionl acute urinary retention or renal failure
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BPH
- Describe Prostatic adenocarcinoma
- Epidemiology
- Where does it arise from?
- Where are the mutations?
- Malignant epithelial prostate tumour
- Epideiology
- Most common malignant tumour in men
- 25% of all male cancers
- 1 in 8 men will develop it in their lifetime
- Less prominent (but important) cause of cancer-related death
- Association with red meat consumption
- 5-10x risk increase if first degree relative is also affected
- Arises from Prostatic Intraepithelial Neoplasia
- Mutations in PTEN, AMACR, GST-pi, p27 and more…
How does prostatic adenoma present?
- Usually asymptomatic; usually diagnosed on biopsy following raised serum prostate-specific antigen or digital rectal examination
- May have lower urinary tract symptoms
- Rarely may present with metastatic disease
- Pathological fracture
What is the prognostic indicator for prostatic adenocarcinoma?
- Most powerful prognositic indicator is the Gleason score
- Higher scores correlate with more aggressive behavior
- Expressed as x + y = z
- Two most common patterns (or most common pattern and worst pattern in biopsy setting)
- Patterns range from 1-5
- 1 and 2 rarely if ever diagnosed so scores typically range from 6-10
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Gleason grade 1, 2 and 3
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Gleason grade 5
- What are testicular germ cell tumors?
- Epidemiology
- Risk factors
- When do they arise?
- Tumours of the testis arising from germ cells
2
- Account for 90% of testicular tumours
- Typically arise in men aged 20-45
3.Risk factors include
- Undescended testis (3-5x increased risk)
- Low birth weight / small for gestational age
4.
Malignant tumours arise from Germ Cell Neoplasia in-situ
- Process likely begins in foetal life
- Amplification of i12p
How do testicular germ cell tumors present?
1.
- Present as painless lump
- 10% present with symptoms related to metastasis
- Back pain
- Cough
- Dyspnoea
- Five histological subtypes
- Single tumour may be purely one subtype or contain a mixture of multiple subtypes
Name 5 germ cell tumors (each histologically different)
- Seminoma
- Embryonal carcinoma
- Post-Pubertal teratoma
- Yolk sac tumor
- Choriocarcinoma
What is the treatment for testicular germ cell tumors?
- Highly sensitive to platinum-based chemotherapy regimes
- Prognosis excellent
- Five year survival is 98% in most countries
Describe the 3 types of Non-germ cell tumors
- Much less common than germ cell tumours
- Lymphoma
- Older men, 5% of all testicular tumours
- Highly aggressive; poor survival rates
•Leydig Cell Tumour
- 3% of all testicular tumours
- May present with precocious puberty if pre-pubertal
- Usually benign
•Sertoli Cell Tumour
- 1% of testicular tumours
- 90% are benign
Describe the following paratesticular diseases
- Epididymal cyst
- Epidymitis
- Varicocele
- Hydrocele
- Adenomatoid tumor
- Epididymal cyst
* Benign fluid filled lump that forms in the epididymis
2Epididymitis
- Usually related to C. trachomatis or N. gonnorrhoeae in men under 35; E. coli in men over 35
3. Varicocele - Dilated venous plexus
4. Hydrocele - Fluid between layers of tunica vaginalis
5. Adenomatoid Tumour - Small tubules lined by mesothelial cells
Describe the following penile diseases
- Lichen sclerosus/Balanitis Xerotica Obliterans
- Zoon’s balanitis
- Condylomas
- Peyronie’s disease
- Penile carcinoma
1.Lichen Sclerosus / Balanitis Xerotica Obliterans
- Inflammatory condition that causes phimosis
- Chronic, often progressive disease, which can lead to phimosis and urethral stenosis, affecting both urinary and sexual function
2.Zoon’s balanitis
- Inflammatory condition that causes red areas
- inflammation of the glans penis.
3.Condylomas
- HPV 6 and 11
- Refers to an infection of the genitals. The two subtypes are: Condyloma acuminata, or genital warts, caused by human papilloma virus subtypes 6, 11, and others. Condylomata lata, white lesions associated with secondary syphilis.
4.Peyronie’s Disease
- Scarring , inflammation, thickening of corpus cavernosa
- Peyronie’s disease is penis problem caused by scar tissue, called plaque, that forms inside the penis. It can result in a bent, rather than straight, erect penis. Most men with Peyronie’s disease can still have sex. But for some, it can be painful and cause erectile dysfunction
5.Penile carcinoma
- Rare, elderly men
- Smoking, HPV, chronic Lichen Sclerosus are risk factors
Describe the following urethral diseases
- Urethritis
- Prostatic urethral polyp
- Urethral carnuncle
- Urethral carcinoma
- Malignant melanoma
- Urethritis
* Common causes: N. gonorrhoeae, C. trachomatis - Prostatic Urethral Polyp
* Papillary lesion in prostatic urethra - Urethral Caruncle
* Common lesion at urethral meatus in women - Urethral Carcinoma
* Rare, more common in women, usually squamous cell carcinoma - Malignant Melanoma
* Rare
Describe the following scrotal diseases
- Epidermoid cyst
- Scrotal calcinosis
- Angiokeratomas
- Fournier’s gangrene
- Scrotal squamous cell carcinoma
- Epidermoid Cyst
- Common
- An epidermoid cyst or epidermal inclusion cyst is a benign cyst usually found on the skin. The cyst develops out of ectodermal tissue. Histologically, it is made of a thin layer of squamous epithelium
- Scrotal Calcinosis
* Rare; may be related to old epidermoid cysts - Angiokeratomas
* Benign vascular lesions - Fournier’s Gangrene
* Necrotising fasciitis; mortality of 15-20% - Scrotal squamous cell carcinoma
- Very rare
- Historical interest; chimney sweep