Difference between revisions of "Gastrointestinal stromal tumour"

Jump to navigation Jump to search
m
mutations
m (mutations)
 
(5 intermediate revisions by one other user not shown)
Line 8: Line 8:
| LMDDx      = [[schwannoma]], [[leiomyoma]], [[leiomyosarcoma]], [[neurofibroma]], [[desmoid-type fibromatosis]]
| LMDDx      = [[schwannoma]], [[leiomyoma]], [[leiomyosarcoma]], [[neurofibroma]], [[desmoid-type fibromatosis]]
| Stains    =
| Stains    =
| IHC        = CD117 +ve, DOG-1 +ve, CD34 +ve, S-100 -ve
| IHC        = CD117 +ve, [[DOG1]] +ve, CD34 +ve, S-100 -ve
| EM        =
| EM        =
| Molecular  = mutation in KIT gene ''or'' PDGFRA gene
| Molecular  = mutation in KIT gene ''or'' PDGFRA gene
Line 34: Line 34:
===Definition===
===Definition===
*Tumour resulting from a mutation in the KIT gene ''or'' PDGFRA (Platelet-derived growth factor receptor, alpha polypeptide) gene.<ref name=pmid17090188/>
*Tumour resulting from a mutation in the KIT gene ''or'' PDGFRA (Platelet-derived growth factor receptor, alpha polypeptide) gene.<ref name=pmid17090188/>
*Cases wild-type for KIT or PDFGRA may harbour defects in the [[succinate dehydrogenase]] complex, NF-1, BRAF, or extremely rarely KRAS.


===Epidemiology===
===Epidemiology===
Line 51: Line 52:
*Large size.
*Large size.
**Often benign if small size.
**Often benign if small size.
*High mitotic rate (for area 5mm^2).
*High mitotic rate (for area 5mm<sup>2</sup>).
*Site - small intestine GISTs worse than stomach GISTs.
*Site - small intestine GISTs worse than stomach GISTs.


Small intestine bad prognosis:<ref name=pmid17090188/>
Small intestine bad prognosis:<ref name=pmid17090188/>
* >5 mitoses/5 mm^2 ''or'' size >10 cm.
* >5 mitoses/5 mm<sup>2</sup> ''or'' size >10 cm.


Stomach bad prognosis:<ref name=pmid17090188/>
Stomach bad prognosis:<ref name=pmid17090188/>
* >5 mitoses/5 mm^2 ''and'' size >5 cm.
* >5 mitoses/5 mm<sup>2</sup> ''and'' size >5 cm.


===Location===
===Location===
Line 68: Line 69:
Notes:
Notes:
*Small intestinal GISTs have a worse prognosis than gastric ones.<ref name=pmid17090188/>
*Small intestinal GISTs have a worse prognosis than gastric ones.<ref name=pmid17090188/>
*GISTs almost never metastasize to the [[lymph node]]s.
*GISTs almost never metastasize to the [[lymph node]]s (except for SDH-B deficient epithelioid GISTs)
**Most common [[metastasis]] locations: [[liver]], abdominal soft tissue.
**Most common [[metastasis]] locations: [[liver]], abdominal soft tissue.


Line 76: Line 77:
** May be epithelioid (round) ~40% of tumours.
** May be epithelioid (round) ~40% of tumours.
** Mixed epithelioid and spindle cell tumours ~10% tumours.
** Mixed epithelioid and spindle cell tumours ~10% tumours.
*+/-Cytoplasmic inclusions.<ref name=pmid7757951>{{cite journal |author=Pasquinelli G, Severi B, Martinelli GN, Santini D, Gelli MC, Tison V |title=Gastro-intestinal stromal tumors: an ultrastructural reinterpretation of the clear cell component |journal=J. Submicrosc. Cytol. Pathol. |volume=27 |issue=2 |pages=251–7 |year=1995 |month=April |pmid=7757951 |doi= |url=}}</ref>
*+/-Cytoplasmic inclusions<ref name=pmid7757951>{{cite journal |author=Pasquinelli G, Severi B, Martinelli GN, Santini D, Gelli MC, Tison V |title=Gastro-intestinal stromal tumors: an ultrastructural reinterpretation of the clear cell component |journal=J. Submicrosc. Cytol. Pathol. |volume=27 |issue=2 |pages=251–7 |year=1995 |month=April |pmid=7757951 |doi= |url=}}</ref> - perinuclear.<ref>{{Cite journal  | last1 = Boşoteanu | first1 = M. | last2 = Boşoteanu | first2 = C. | last3 = Deacu | first3 = M. | last4 = Aşchie | first4 = M. | title = Differential diagnosis of a gastric stromal tumor: case report and literature review. | journal = Rom J Morphol Embryol | volume = 52 | issue = 4 | pages = 1361-8 | month =  | year = 2011 | doi =  | PMID = 22203947 }}</ref>
*Classically splits the layers of the ''muscularis propria'' - as this is where the ''interstitial cells of Cajal'' are located.<ref name=pmid16402273>{{cite journal |author=Agaimy A, Wünsch PH |title=Gastrointestinal stromal tumours: a regular origin in the muscularis propria, but an extremely diverse gross presentation. A review of 200 cases to critically re-evaluate the concept of so-called extra-gastrointestinal stromal tumours |journal=Langenbecks Arch Surg |volume=391 |issue=4 |pages=322–9 |year=2006 |month=August |pmid=16402273 |doi=10.1007/s00423-005-0005-5 |url=}}</ref>
*Classically splits the layers of the ''muscularis propria'' - as this is where the ''interstitial cells of Cajal'' are located.<ref name=pmid16402273>{{cite journal |author=Agaimy A, Wünsch PH |title=Gastrointestinal stromal tumours: a regular origin in the muscularis propria, but an extremely diverse gross presentation. A review of 200 cases to critically re-evaluate the concept of so-called extra-gastrointestinal stromal tumours |journal=Langenbecks Arch Surg |volume=391 |issue=4 |pages=322–9 |year=2006 |month=August |pmid=16402273 |doi=10.1007/s00423-005-0005-5 |url=}}</ref>  
*+/-Skenoid fibres - extracellular collagen bundles<ref name=pmid15798063/> ~ 2-5 x 60 micrometers - uncommon finding.
*+/-Skenoid fibres - extracellular collagen bundles<ref name=pmid15798063/> ~ 2-5 x 60 micrometers - uncommon finding.
**Not seen in gastric GISTs.<ref name=pmid12692202/>
**Not seen in gastric GISTs.<ref name=pmid12692202/>
Line 114: Line 115:
*CD117 +ve in 95%.<ref name=pmid17090188/>
*CD117 +ve in 95%.<ref name=pmid17090188/>
**[[Mast cell]]s are the internal positive control.
**[[Mast cell]]s are the internal positive control.
*DOG1 +ve.<ref name=pmid19011564>{{Cite journal  | last1 = Liegl | first1 = B. | last2 = Hornick | first2 = JL. | last3 = Corless | first3 = CL. | last4 = Fletcher | first4 = CD. | title = Monoclonal antibody DOG1.1 shows higher sensitivity than KIT in the diagnosis of gastrointestinal stromal tumors, including unusual subtypes. | journal = Am J Surg Pathol | volume = 33 | issue = 3 | pages = 437-46 | month = Mar | year = 2009 | doi = 10.1097/PAS.0b013e318186b158 | PMID = 19011564 }}</ref>
*[[DOG1]] +ve.<ref name=pmid19011564>{{Cite journal  | last1 = Liegl | first1 = B. | last2 = Hornick | first2 = JL. | last3 = Corless | first3 = CL. | last4 = Fletcher | first4 = CD. | title = Monoclonal antibody DOG1.1 shows higher sensitivity than KIT in the diagnosis of gastrointestinal stromal tumors, including unusual subtypes. | journal = Am J Surg Pathol | volume = 33 | issue = 3 | pages = 437-46 | month = Mar | year = 2009 | doi = 10.1097/PAS.0b013e318186b158 | PMID = 19011564 }}</ref>
**More sensitive than CD117.


Others:
Others:
Line 162: Line 162:
NEGATIVE: Desmin, S-100.
NEGATIVE: Desmin, S-100.
PROLIFERATION (Ki-67): <1%.
PROLIFERATION (Ki-67): <1%.
</pre>
====Incidental GIST====
<pre>
Partial Stomach, Sleeve Gastrectomy:
- Stomach wall with incidental GASTROINTESTINAL STROMAL TUMOUR (GIST), 2 mm in maximal dimension.
-- Margin clear.
- Gastric mucosa within normal limits.
Comment:
The tumour stains as follows:
POSITIVE: DOG1, CD117, CD34.
NEGATIVE: desmin, S-100.
PROLIFERATION (Ki-67): <2%.
</pre>
</pre>


110

edits

Navigation menu