Urothelial dysplasia
Urothelial dysplasia, also low-grade (urothelial) dysplasia, is a lesion of the urothelium in the ISUP/WHO 2004 classification.[1] It is precursor lesion to urothelial carcinoma that is less worrisome than urothelial carcinoma in situ (also known as high-grade (urothelial) dysplasia).
General
The ISUP/WHO classification of flat urothelial lesions is:[1]
- Reactive urothelial atypia.
- Flat urothelial hyperplasia.
- Urothelial atypia of unknown significance.
- Urothelial dysplasia (low-grade dysplasia).
- Urothelial carcinoma in situ (high-grade dysplasia).
- Invasive urothelial carcinoma.
Microscopic
Features:[2]
- Mild nuclear enlargement (~3x a resting lymphocyte) and hyperchromasia.
- Slight disorganization of the architecture.
- Some maturation to the surface.
- Mitotic figures - occasional, none atypical.
Notes:
- It is probably not a good idea to make this diagnosis without immunohistochemistry.
- This diagnosis not made on frozen section.
DDx:
- Benign urothelium with reactive changes.
- Urothelial carcinoma in situ.
Images
IHC
A comparison between benign, dysplasia and UCIS:[3]
| Diagnosis | CK20 | Ki-67 | p53 |
|---|---|---|---|
| Benign (reactive) | umbrella cells +ve only | -ve <=10% of cells (+/-rare basal cells) | -ve <20% of cells (+/-weak staining) |
| Urothelial dysplasia | +ve non-umbrella cells +ve (~30% of cases) | +ve >10% of cells (~40% of cases) | +ve >=20% of cells (~70% of cases) |
| Urothelial carcinoma in situ (UCIS) | +ve non-umbrella cells (~70% of cases) | +ve >10% of cells (~95% of cases) | +ve >=20% of cells (~80% of cases) |
See also
References
- ↑ 1.0 1.1 Hodges, KB.; Lopez-Beltran, A.; Davidson, DD.; Montironi, R.; Cheng, L. (Feb 2010). "Urothelial dysplasia and other flat lesions of the urinary bladder: clinicopathologic and molecular features.". Hum Pathol 41 (2): 155-62. doi:10.1016/j.humpath.2009.07.002. PMID 19762067.
- ↑ URL: http://pathology.jhu.edu/bladder/image1.cfm?case_number=10&image_number=1. Accessed on: 31 December 2013.
- ↑ Mallofré, C.; Castillo, M.; Morente, V.; Solé, M. (Mar 2003). "Immunohistochemical expression of CK20, p53, and Ki-67 as objective markers of urothelial dysplasia.". Mod Pathol 16 (3): 187-91. doi:10.1097/01.MP.0000056628.38714.5D. PMID 12640096.