48,830
edits
(→References: chg. cat.) |
(→Microscopic: more, subtypes) |
||
Line 15: | Line 15: | ||
==Microscopic== | ==Microscopic== | ||
Features: | Features: | ||
* | *Usu. cellular lesion. | ||
* | *Fasciclar arrangement: | ||
**Whorled look at low power. | **Whorled look at low power. | ||
**Groups of spindle cells cut peripendicular to their long axis adjacent to groups of spindle cells cut in the plane of their long axis. | **Groups of spindle cells cut peripendicular to their long axis adjacent to groups of spindle cells cut in the plane of their long axis. | ||
*Features of malignancy (need all three): | *Features of malignancy (need all three): | ||
*# | *#Nuclear atypia. | ||
*# | *#Tumour cell necrosis. | ||
*#*Should be patchy/multifocal. | *#*Should be patchy/multifocal. | ||
*#**Zonal necrosis is suggestive of vascular cause. | *#**Zonal necrosis is suggestive of vascular cause. | ||
*#Mitoses - '''key feature''' - definitions | *#Mitoses - '''key feature''' - definitions suffer from [[HPFitis]]: | ||
*#*10 mitoses/HPF. | *#*>=10 mitoses/HPF - if spindled.<ref name=Ref_GP281>{{Ref GP|281}}</ref> | ||
*#*5 mitoses/HPF - if epithelioid. | *#*>=5 mitoses/HPF - if epithelioid.<ref name=Ref_GP281>{{Ref GP|281}}</ref> | ||
*#*2 mitoses/HPF - if myxoid. | *#*>=2 mitoses/HPF - if myxoid.<ref name=Ref_GP281>{{Ref GP|281}}</ref> | ||
*#*>=1 mitosis/HPF - if cutaneous.<ref name=pmid21358302>{{cite journal |author=Kraft S, Fletcher CD |title=Atypical intradermal smooth muscle neoplasms: clinicopathologic analysis of 84 cases and a reappraisal of cutaneous "leiomyosarcoma" |journal=Am. J. Surg. Pathol. |volume=35 |issue=4 |pages=599–607 |year=2011 |month=April |pmid=21358302 |doi=10.1097/PAS.0b013e31820e6093 |url=}}</ref> | *#*>=1 mitosis/HPF - if cutaneous.<ref name=pmid21358302>{{cite journal |author=Kraft S, Fletcher CD |title=Atypical intradermal smooth muscle neoplasms: clinicopathologic analysis of 84 cases and a reappraisal of cutaneous "leiomyosarcoma" |journal=Am. J. Surg. Pathol. |volume=35 |issue=4 |pages=599–607 |year=2011 |month=April |pmid=21358302 |doi=10.1097/PAS.0b013e31820e6093 |url=}}</ref> | ||
Line 39: | Line 39: | ||
**[http://commons.wikimedia.org/wiki/File:Cutaneous_leiomyosarcoma_-_high_mag.jpg Cutaneous leiomyosarcoma - high mag. (WC)]. | **[http://commons.wikimedia.org/wiki/File:Cutaneous_leiomyosarcoma_-_high_mag.jpg Cutaneous leiomyosarcoma - high mag. (WC)]. | ||
===IHC | ===Subtypes=== | ||
Variants:<ref name=Ref_GP284>{{Ref GP|284}}</ref> | |||
*Spindled leiomyosarcoma (leiomyosarcoma NOS) - see above. | |||
*Epithelioid leiomyosarcoma. | |||
*Myxoid leiomyosarcoma. | |||
*Leiomyosarcoma with prominent intravascular growth. | |||
*Leiomyosarcoma with osteoclast-type cells. | |||
*Leiomyosarcoma with clear cells. | |||
*Leiomyosarcoma with xanthoma-type cells. | |||
====Epithelioid leiomyosarcoma==== | |||
Features:<ref name=Ref_GP281>{{Ref GP|281}}</ref> | |||
*>50% epithelial appearance. | |||
*>=5 mitoses/HPF - definition suffers from [[HPFitis]]. | |||
====Myxoid leiomyosarcoma==== | |||
Features:<ref name=Ref_GP281>{{Ref GP|281}}</ref> | |||
*>=2 mitoses/HPF - definition suffers from [[HPFitis]]. | |||
*May have minimal nuclear atypia. | |||
==IHC== | |||
*CD10 -ve (important in the context of uterine lesions -- +ve in [[endometrial stromal sarcoma]]). | *CD10 -ve (important in the context of uterine lesions -- +ve in [[endometrial stromal sarcoma]]). | ||
*Positive for SMC markers. | *Positive for SMC markers. |
edits