49,006
edits
Difference between revisions of "Squamous metaplasia of the rectum/anus"
Jump to navigation
Jump to search
Squamous metaplasia of the rectum/anus (view source)
Revision as of 02:42, 16 June 2016
, 02:42, 16 June 2016→General
(create) |
|||
| (8 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
'''Squamous metaplasia of the anus''' is a metaplastic change of the columnar epithelium. It can histologically mimic [[anal intraepithelial neoplasia]] (AIN), especially. [[high-grade squamous intraepithelial lesion]] (HSIL). | '''Squamous metaplasia of the rectum/anus''' is a metaplastic change of the columnar epithelium of the rectum. | ||
It can histologically mimic [[anal intraepithelial neoplasia]] (AIN), especially. [[high-grade squamous intraepithelial lesion]] (HSIL). | |||
==General== | |||
*Present in the transformation zone between the columnar epithelium of the [[rectum]] and squamous epithelium of the [[anus]] - similar to the transformation zone of the [[uterine cervix]].<ref name=pmid20436833>{{Cite journal | last1 = Pineda | first1 = CE. | last2 = Welton | first2 = ML. | title = Management of anal squamous intraepithelial lesions. | journal = Clin Colon Rectal Surg | volume = 22 | issue = 2 | pages = 94-101 | month = May | year = 2009 | doi = 10.1055/s-0029-1223840 | PMID = 20436833 }}</ref> | |||
Note: | |||
*The anatomy & histology of the anus covered in the ''[[anus]]'' article. | |||
==Microscopic== | |||
Features: | |||
* Uniform cell spacing - no crowding - '''key feature'''. | |||
* Nuclei are uniform size and round. | |||
** +/-[[Nucleoli]] present. | |||
*Distinct cell borders | |||
* +/-Intercellular bridges (due to edema) - common. | |||
Negatives: | |||
* No mitoses/rare basal mitoses - think cancer/AIN if you see 'em. | |||
* Usually no hyperchromatism (think cancer/CIN if you see it). | |||
DDx: | |||
*[[Anal intraepithelial lesion]]. | |||
===Images=== | ===Images=== | ||
| Line 16: | Line 39: | ||
==See also== | ==See also== | ||
*[[Squamous metaplasia]]. | *[[Squamous metaplasia]]. | ||
==References== | |||
{{Reflist|1}} | |||
[[Category:Gastrointestinal pathology]] | [[Category:Gastrointestinal pathology]] | ||
[[Category:Dermatopathology]] | [[Category:Dermatopathology]] | ||