Primary Extra-gastrointestinal Stromal Tumors Research Articles

Primary Extra-Gastrointestinal Stromal Tumors (E-GIST) of the Liver, about Two Cases and Review of the Literature Oncology Hospital Experience at Chu Hassan II in FES

Introduction: Primary extra-gastrointestinal stromal tumors (E-GIST) of the liver are rare. The clinical presentation can range from asymptomatic to bleeding or manifestations of mass effect. Cancer surgery followed by adjuvant treatment with imatinib is the standard of care. However, in special circumstances, a cytoreductive approach may represent a therapeutic option. We describe here the case of two patients who presented with a painful and protruding epigastric mass, the first case was a localized E-GIST candidate for neoadjuvant treatment with imatinib with complete resection surgery thereafter with very good evolution, and the second is that of an E-GIST of the liver at an advanced stage with an evolution very quick to death. Conclusion: Primary liver E-GIST is a rare condition. Treatment is based on systemic therapy and total resection surgery. However, cytoreductive surgery will be required when complete resection is not possible.

Malignant extra-gastrointestinal stromal tumor of the liver: A case report.

Extra-gastrointestinal stromal tumors (EGISTs) predominantly occur outside of the gastrointestinal tract, and their biological and histological characteristics are similar to those of GISTs. Primary EGIST occurrence in the liver is extremely rare. The present study reports a case of primary EGIST in the caudate lobe of the liver in a 61-year-old Chinese man. Contrast-enhanced computed tomography revealed a 7.3×5.1-cm heterogeneously enhanced neoplasm with solid and cystic components located in the caudate lobe of the liver. The patient underwent caudate lobe (specifically, Spiegel lobe) resection. Immunohistochemical analysis of the resected tumor revealed a strong positivity for cluster of differentiation (CD)117, discovered on GIST-1 and CD34. Thus, based on the histological and immunohistochemical findings, the final diagnosis was primary hepatic EGIST. Follow up was conducted at 3-month intervals for the first year and 6-months thereafter. The patient was asymptomatic without any sign of recurrence during the follow-up period. Lab tests were in normal range, and no mass was found in CT scan.

Coexisting and possible primary extra-gastrointestinal stromal tumors of the pancreas and liver: A single case report.

Gastrointestinal stromal tumors (GIST) are mesenchymal neoplasms of the gastrointestinal tract (GI) that are defined, in part, by the expression of CD117, a c-Kit proto-oncogene protein. GISTs emerge outside of the GI at a very low frequency, typically in a single organ or location. GISTs that occasionally emerge outside of the GI are classified as extra-gastrointestinal stromal tumors (EGIST). The present study reports an extremely rare case of EGIST detected in the pancreas and the liver. The pancreatic and liver tumors were 4.5×2.5 cm and 2.0×1.5 cm in size, respectively. Both tumors consisted of CD117-positive spindle cells with a similar mitotic rate of 1–2 per 50 high power fields. The pancreatic and the hepatic EGISTs were at a low risk of malignancy, and both tumors were proposed to be primary stromal tumors. To the best of our knowledge, this is the first report of likely primary EGIST identified in the pancreas and liver of the same patient.

English

Mesenchymal tumors originating from the wall of the gastrointestinal tract have contributed to fascinating literature worldwide regarding their controversial histogenesis. Most common mesenchymal tumor arising in the gastrointestinal tract is gastrointestinal stromal tumor (GIST). (1,2) Apart from gastrointestinal tract, GISTs that involve omentum, mesentery and retroperitoneum are commonly known as extra gastrointestinal stromal tumors (EGISTs) Though there are many studies regarding various aspects of GISTs, yet primary EGISTs literature are limited. EGISTs are often included in large studies of stromal tumors, in which they account for less than 10% of overall cases. In most cases a preoperative diagnosis is not possible, and the patient undergoes a surgical operation for the generic diagnosis of abdominal mass. Here were report two rare presentations in the form of non exophytic intraluminal GIST and huge EGIST.

Primary gastrointestinal stromal tumor of the prostate: A case report and literature review.

Extragastrointestinal stromal tumors (EGISTs) are relatively rare soft tissue neoplasms arising from the extra gastrointestinal tract. The current study presents a case of primary EGIST of the prostate observed in a 55-year-old male. Imaging studies showed a 10×10.5×9.5-cm prostate mass. On histological observation, the mass was separated from the rectum serosa and exhibited a high mitotic count (8/50 high-power fields). The results of immunohistochemical staining showed positive immunoreactivity for cluster of differentiation (CD)117 (c-kit), CD34 and DOG1 in the tumor. On mutation analysis, loss of heterozygosity of the c-kit gene was observed in the prostatic EGIST; however, the platelet-derived growth factor receptor-α (PDGFRA) gene was considered to be normal. Therefore, as EGIST of the prostate is rare, there is a requirement for the confirmation of the diagnosis to be based on immunohistochemistry and mutation analysis (of c-kit and PDGFRA).

Primary extragastrointestinal stromal tumors: A clinicopathological and immunohistochemical study-A tertiary care center experience

Extra gastrointestinal stromal tumors (EGIST) are uncommon compared to their gastrointestinal counterparts. EGISTs involve omentum, mesentery, retroperitoneum, pancreas, and pelvis. Ten EGISTs were analyzed in this study from January 1995 to November 2011. They were analyzed with respect to clinical features, imageological, histopathological, and immunohistochemical findings. The immunohistochemical stains used were Smooth muscle actin (SMA), Desmin, S-100 protein, CD34 and CD-117. There was slight female preponderance with wide age range. Four of the tumors were in retroperitoneum, three in mesentery, and two in omentum and one in pelvis. Histopathologically majority were spindle cell tumors. Immunohistochemically CD117 was consistently positive followed by CD34. Smooth muscle actin was positive in eight cases, S-100 protein and desmin were positive in two cases each. EGISTs are rare and should be considered in the differential diagnosis of the mesenchymal tumors and immunohistochemistry helps to confirm the diagnosis. Further study with better follow-up is desired to characterize these uncommon tumors.

Primary extragastrointestinal stromal tumor arising in the pancreas: report of a case

Primary extragastrointestinal stromal tumors (EGISTs) arising in the pancreas are extremely rare, with only ten cases documented to our knowledge. We report a further case of EGIST of the pancreas. The patient was a 55-year-old man who presented with postprandial abdominal discomfort. Abdominal computed tomography and magnetic resonance imaging showed a lobulated heterogenous enhancing mass, 11cm in diameter, in the abdominal cavity. No regional lymphadenopathy, ascites, or metastasis was seen radiologically. There was no obvious lesion in the stomach or small intestine. The initial diagnosis was a solid pseudopapillary tumor or serous cystic neoplasm. The patient underwent distal pancreatectomy with splenectomy. Microscopically, the tumor consisted of spindle cells arranged in short fascicles. Mitotic figures were seen in 7/50 high-power fields. Immunohistochemical examination revealed strongly positive staining for CD117. Based on these findings, the final pathologic diagnosis was a primary EGIST of the pancreas. This case consolidates the possibility that this rare tumor can involve the pancreas as a primary site and should be included in the differential diagnosis of cystic lesions in this site.

A Single-Institution Experience with Eight CD117-Positive Primary Extragastrointestinal Stromal Tumors: Critical Appraisal and a Comparison with Their Gastrointestinal Counterparts

IntroductionGastrointestinal stromal tumors (GISTs) arising from outside the gut wall also termed extragastrointestinal stromal tumors (EGISTs) are reported to be rare. Presently, their pathogenesis remains controversial, and recently, it has been proposed that EGISTs may be the result of extensive extramural growth of GISTs which lose contact with the gut wall. This study presents a single-institution experience with eight EGISTs and compares their clinicopathological features with mural GISTs in order to determine further insight to their possible origin. MethodsBetween 1997 and 2008, 156 patients with pathologically proven CD117-positive primary GISTs were retrospectively reviewed. Eight tumors were identified as EGISTs, 104 were gastric GISTs, and 44 were small-bowel GISTs. Mural GISTs were classified as extramural or intra/transmural according to their gross pattern of growth. ResultsThere were five male and three female patients with a median age of 58 years (range, 42–81 years). All patients were symptomatic, and the tumors were located in the greater omentum (n = 2), lesser sac (n = 2), lesser omentum, retroperitoneum, small-bowel mesentery, and pancreas. The median tumor size was 140 mm (range, 55 to 220 mm). Seven of eight EGISTs were found to be in close association to the adjacent gut wall. Pathological examination demonstrated that two tumors demonstrated focal involvement of the muscularis propria of the adjacent gut wall. Four tumors demonstrated tumor abutting or adherent to the serosa but no muscle involvement and one tumor was separated from the serosa. Comparison between the clinicopathological features of EGISTs with extramural GISTs and intra/transmural GISTs demonstrated that EGISTs were significantly larger [140 range (55–220) mm vs 80 (5–260) mm vs 50 (15–190) mm, P = 0.049, P < 0.001 respectively]. ConclusionThe occurrence of true EGISTs is rare. Most cases demonstrate some form of communication or contact with the gut wall, and EGISTs are significantly larger than extramural or intra/transmural GIST. These observations suggest that most, if not all, cases of EGISTs are likely to represent mural GISTs with extensive extramural growth with eventual loss of contact with the muscle layer of the gut.