Papillary
Urothelial Carcinoma
Epidemiology:
- Similar
to bronchogenic carcinoma
- M >
F (~3:1)
- Industrialized
> developing nations
- Urban >
rural dwellers
- 50-80y
(80%)
- Not familial
(rare exceptions)
- Associated
factors:
- Smoking
(most important)
- Industrial
exposure to arylamines
- Schistosoma
haematobium infection (30% of associated CA are urothelial)
- Egypt
- Sudan
- Long-term
analgesic use
- Cyclophosphamide long-term exposure
- Radiation
exposure
Common sites:
- lateral
or posterior walls at the bladder base
- often
multifocal
Gross features:
Histologic features:
- true
papillae with urothelial lining that is thicker than benign papilloma
- low-grade:
- orderly
architectural and cytological appearance
- evenly
spaced cells
- loss
of polarity
- cohesive
cells
- mild
nuclear atypia:
- scattered
hyperchromatic nuclei
- mitoses
infrequent and predominantly towards the base
- mild
nuclear pleomorphism
- increased
n:c ratio
- +/-
umbrella cell layer
- high-grade:
- discohesive
cells
- architectural
disarray with loss of polarity
- large,
hyperchromatic nuclei
- some
cells showing frank anaplasia
- frequent
mitoses, particularly in upper layers
- including
atypical mitoses
- type
I:
- limited
amount of cytoplasm
- low-grade
nuclei
- type
II:
- ample
cytoplasm
- eosinophilic
- higher-grade
nuclei
- may
see areas of squamous carcinoma
- glomeruloid structures may be
present
Immunophenotype:
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Marker:
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Sensitivity:
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Specificity:
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Molecular features:
- only
rarely familial
- heterogenous
cytogenetic and molecular alterations
- chromosome
9 monosomy or deletions (30-60%)
- tumour
suppressor gene p16INK4a
- numerous
other tumour suppressor loci
- deletions
of 17p (including p53 region), 13q (retinoblastoma gene), 11p
- p53
mutations
- important
prognostic factors:
- grade
- lamina
propria invasion
- carcinoma
in situ
- low-grade
papillary urothelial CA has a 98% 10-year
survival rate
- <
10% progress to higher-grade lesions
- High-grade
papillary urothelial CA has a 40% 10-year
survival
- Squamous cell carcinoma is worse
(70% mortality in 1 year)
- BCG (attenuated
strain of Mycobacterium
tuberculosis) is used for those with a high risk of recurrence and/or
progression:
- CIS
- high-grade
papillary urothelial CA
- multifocal
papillary urothelial CA
- rapid
recurrence of papillary urothelial CA
- lamina
propria invasion
- Radical
cystectomy is performed for:
- Tumour invading muscularis propria
- CIS
or HG urothelial CA refractory to BCG
- CIS
extending into the prostatic ducts (beyond the reach of BCG)
Other features:
- muscularis propria
invasion imparts a poor prognosis (50% 5-year survival)