Urological pathology Flashcards
What is the histological structure of the wall of the renal pelvis, ureter, bladder and urethra?
- urothelium
- lamina propria
- muscularis propria (detrusor in bladder)
- adventitia (perivesical fat in bladder)
What are the zones of the prostate gland?
- transition
- central
- peripheral
Prostate gland produces alkaline secretion to neutralise acidic environment of vagina. Gland is made up of numerous acini (glands) + ducts lined by epithelial cells, embedded in a stroma composed of sm muscle cells + fibroblasts.
What do the prostatic acini do?
- secrete prostatic juice
- drain into the prostatic urethra via duct system
What do the stromal cells contain?
- 5 a-reductase
- converts T -> DHT (more potent)
- maintaining suitable levels of androgens in prostate
What are common causes of macroscopic (frank) haematuria?
-
UPPER TRACT:
- kidney cancer (renal cell carcinoma)
- stone in kidney or ureter
- trauma
-
LOWER TRACT:
- bladder cancer
- BPH
- infection (bacterial cystitis)
For macroscopic haematuria, following a full history and examination, what investigations are useful to request?
- MSU for MC+S
- urine cytology
- flexible cystoscopy +/- biopsy
What are LUTS?
- lower urinary tract symptoms
- frequency, urgency, nocturia, hestiancy, poor flow + terminal dribbling
- suggests problem in bladder or prostate
- important to realise that LUTS not specific for any particular pathology
What are some causes of LUTS?
- BPH
- UTI
- urinary tract stones
- bladder cancer
- prostate cancer (LUTS are a late feature of this)
What is the most common malignant tumour of the kidney?
-
renal cell carcinoma (RCC)
- most common type of RCC -> clear renal cell carcinoma
- RCCs are adenocarcinomas, arise from epithelia lining renal tubules
What are the risk factors for development of RCC?
- male gender (4M:1F)
- inc age (most cases occur in over 50)
- smoking
- obesity
-
familial syndromes - Von Hippel Lindau sydndrome
- rare autosomal dominant genetic disease
- predisposes individuals to certain benign + malignant tumours incl RCC + phaeochromocytoma
How is renal cell carcinoma graded?
Fuhrman grading system
- grade 1: tumour cell nuclei closely resembal normal -> less aggressive (better prognosis)
- grade 4: tumour cell nuclei larger + pleomorphic etc -> more aggressive (worse prognosis)
How is renal cell carcinoma staged?
- TNM system
- size of the primary tumour important in determining the T stage
What is the clinical presentation of RCC?
There is a triad, however it is uncommon in clinical practice:
- loin pain
- loin mass
- haematuria
Other common presentations of kidney cancer include:
- incidental finding on scan
- presentation w/ symptoms/signs of metastatic disease (lung or bone) eg. bone pain, SoB
- paraneoplastic syndrome eg. hypercalcaemia, erythrocytosis, amyloidosis
What type are the majority of bladder cancers?
- urothelial carcinomas
- malignant tumour arising from urethelium
- transitional cell carcinoma is an old term
Wht are risk factors for developing urothelial carcinoma?
- cigarette smoking
- industrial exposure to certain industrial dyes + solvents (eg arylamines)
Bladder cancers are staged using the TNM system. What are key features of the TNM system regarding bladder cancer?
- superficial tumours are Ta or T1
- muscle invasive tumours are T2, T3, or T4
- CIS is Tis
How do you clinically classify bladder cancer?
Three main groups:
- low-risk bladder cancer (superficial tumours Ta T1 + low grade)
- high-risk bladder cancer (muscle invasive T2 or worse + high grade)
- carcinoma in situ (CIS) - precancer
Describe low-risk bladder cancers and their extent of invasion
- confined to mucosa or invade into lamina propria
- do not invade into muscularis propria (detrusor) or beyond
- often low grade
- tend to be composed of frond-like papillary growths
- papillary refers to finger-like projection (w/ fibrovascular core)
How are superficial urothelial carcinomas (low-risk bladder cancers) managed?
- removed at cystoscopy by TURBT
- after removal:
- high chance tumour will recur
- low chance tumour will transform into high risk
Therefore, pts diagnosed w/ superficial urothelial carcinoma require regular check cystoscopies
Describe high-risk (muscle-invasive) bladder cancer and how they differ to low-risk cancers
- invade into detrusor muscle or beyond
- tend to be solid rather than papillary
- almost always high grade
- have much worse prognosis than low-risk tumours
- more likely to spread to regional nodes + metastasise to distant sites
- radical treatment required for cure, often cystectomy (removal of bladder) +/- other organs eg. uterus
Describe urothelial carcinoma in situ (CIS)
- flat lesion
- ureothelium contains cells that display nuclear features
- associated w/ malignancy (eg pleomorphism, mitoses etc)
- BUT no invasion through basement membrane
- form of precancer: left untreated, ~40% progress to muscle invasive cancer
- diagnosis of CIS bladder v serious due to chances of prog
What is blue light cystoscopy?
- may be used to identify CIS
- ~1hr before cystoscopy, Hexyl aminolevulinate (HAL) inserted into bladder via a urinary catheter
- urologist performs cystoscopy using special cystoscope + blue light
- CIS cells absorb chemical + then fluoresce red in blue light
- background normal urothelial cells do not absorb chemical so do not fluoresce
- thus, urologist can identify areas of CIS bc they stand out