Epidemiology
- Estimated 3000 new cases / year in Australia (2300 men)
- 11th most common cancer in Aust
- Median age 76
- 3-4 : 1 men
70 – 80 % of bladder cancer is non invasive
- 70 % Ta
- 20 % T1
- 10 % CIS
Risk factors
Bladder cancer is a disease of ageing and environmental exposure.
- Smoking – 4 x relative risk factor for smokers, 50 % cases directly attributable to smoking
- Occupational exposures:
- Aniline dyes, aromatic amines
- Fabric, rubber, textile, dye and latex industries
- Radiation
- Drugs – cyclophosphamide, phenacetin, pioglitazone
- Schistosomiasis
- Chronic infection and inflammation and long term catheterisation
- Lynch syndrome
Delay in diagnosis for women who are subsequently diagnosed at later stage and have worse prognosis – often treated for recurrent UTIs before urological evaluation.
Approx 80 % of patients with CIS have storage LUTS.
Family history is not a clear risk factor, but some genetic susceptibility is apparent (N-acetyltransferases, glutathione transferases, Lynch syndrome, Li Fraumeni)
Differential diagnosis of bladder mass:
Cystitis cystica – proliferation of urothelium into buds, which grow downwards into lamina propria and differentiate into cystic deposits.
Cystitis glandularis – pathological spectrum same as cystitis cystica but invaginated urothelium undergoes glandular metaplasia.
Intestinal metaplasia (glandular metaplasia) – replacement of urothelium with colonic mucosa or goblet cells – unclear association with adenocarcinoma, probably warrants surveillance.
Squamous metaplasia is usually seen in female trigone and is essentially a normal variant. It is non-keratinising.
Keratinising squamous metaplasia (leukoplakia) is rare, can affect the entire bladder and is considered possibly premalignant.
Papillomas and inverted papillomas are benign proliferative lesions associated with chronic inflammation or bladder outlet obstruction – often found on the trigone.
Nephrogenic adenomas have the microscopic appearance of renal parenchyma and are benign.
Amyloidosis – benign, abnormal deposition of amyloid protein. Can be endoscopically resected, suggestion of DMSO for refractory or recurrent disease. Physician input to exclude other systemic disease. Histology – amorphous eosinophilic appearance on H&E stain, apple green birefringence under polarised light and Congo Red staining.