Malignant extra-gastrointestinal stromal tumor of the pancreas: Report of two cases and review of the literature

Table 1 Previous cases report of Pancreatic gastrointestinal stromal tumor

Ref.	Presentation	Case No.	Location in pancreas	Pathological and immunohistochemical findings	Therapy	Follow-up
Boyer et al[15]2001	Abdominal pain	2	Both of two cases were in the head	A 5.0 cm solid mass with central necrosis; positive for CD117 and CD34; negative for S100	Biopsy of liver lesion and partial duodenopancreatectomy;	NA
Neto et al[6] 2004	Epigastric pain, bloating, weight loss	1	Body	A 20.0 cm solid cystic mass with necrotic foci; mitotic count (120/50 HPF); positive for CD117 and CD34; negative for cytokeratins 7 and 20, desmin and synaptophysin	Distal pancreatectomy and splenectomy; treated with imatinib mesylate	Recurrence with peritoneal and retroperitoneal nodal disease 1 mo after surgery
Yamaura et al[7]2004	Incidental finding	1	Tail	A 14.0 cm solid mass with cystic degeneration; few mitoses; positive for CD34 and vimentin; negative for SMA and S100	Distal pancreatectomy splenectomy, and partial gastrectomy	No evidence of disease recurrence at 30 mo
Krska et al[8] 2005	Abdominal pain	1	Body and head	A 17.0 cm mass; mitotic count: 1/50 HPF; positive for CD34 and vimentin; negative for S100, chromogranin, actin, and CD117	Partial pancreatectomy	No evidence of disease recurrence at 30 mo
Pauser et al[11]2005	Incidental finding/abdominal discomfort	2	Tail and body	A 3.0 cm solid mass with positive for CD117 and CD34, cell negative for SMA;A 2.0 cm solid mass with positive for CD117 and CD34, cell negative for SMA	Distal pancreatectomy splenectomy, and partial gastrectomy	No evidence of disease at 24 and 48 mo
Daum et al[9]2005	Incidental finding	1	Head	A 10.0 cm mass with central hemorrhage mitotic count: 2/50 HPF; negative for CD117, vimentin, actin, S100, CD34, desmin, and cytokeratins	Whipple procedure; imatinib	No evidence of disease recurrence at 6 mo
Showalter et al[10] 2008	Incidental finding on workup for back pain	1	Tail	A 7.0 cm solid mass; mitotic count: 3/50 HPF; positive for CD117; negative for S100 protein and SMA	Laparoscopic distal pancreatectomy and splenectomy	No evidence of disease recurrence at 27 mo
Yan et al[13]2008	Nausea and vomiting	1	Uncinate process	A 2.4 cm pancreatic mass with spindle cells and mild atypia; positive for CD117; negative for desmin	NA	NA
Harindhanavudhi et al[14]2009	Fatigue and weakness	1	Body	A 16.0 cm × 11.0 cm solid cystic mass; positive for CD117, CD34	Exploratory laparotomy with cystojejunostomy and biopsy of cyst wall	NA
Trabelsi et al[12] 2009	Abdominal pain	1	Head	A 10.5 cm × 8.0 cm × 3.0 cm mass with spindle and epithelioid cells Mitotic: 6/50 HPF. Positive for CD117 (c-Kit) and CD34, negative for SMA, S100, synaptophysin and cytokeratins	Hemipancreaticoduodenectomy with antrectomy and partial colectomy	No evidence of disease recurrence at 10 mo
Vij et al[5] 2011	Weakness, postprandial	1	Head	A 6.5 cm × 6.0 cm solid mass with pleomorphic Spindle cells; mitosis: 12-15/50 HPF; positive for CD117; negative for CD34, SMA, desmin, S100 and cytokeratins	Whipple procedure; Imatinib on protocol	Developed liver metastasis 24 mo after surgery
Rubin et al[16]2011	fullness and painabdominal pain	1	Body and tail	A 25.0 cm × 30.0 cm solid mass positive for CD117, CD34 and VIM; negative for S100, NF, DES, SMA, and CK	Distal pancreatectomy splenectomy	NA
Present case 1	Incidental finding	1	Tail	A 6.0 cm × 8.0 cm solid mass with spindle cells mitotic: < 5/50 HPF; positive for CD117, CD34, and s-100 protein, negative for DOG-1, Desmin, NF, synaptophysin, Chromogranin A and cytokeratin	Distal pancreatectomy splenectomy	No evidence of disease recurrence at 36 mo
Present case 2	Incidental finding	1	Head	A 4.0 cm × 5.0 cm × 6.0 cm solid mass with spindle cells mitosis: > 5/50 HPF. Positive for CD117, S100 protein and DOG-1, negative for SMA, synaptophysin, and cytokeratin	Pancreatic head tumor resection	Developed liver metastasis 12 mo after surgery progression-free survival for 36 mo after two times of TACE and oral imatinib