Gastrointestinal stromal tumors: A multidisciplinary challenge

Abstract

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors located in the alimentary tract. Its usual manifestation is gastrointestinal bleeding. However, small asymptomatic lesions are frequently detected as incidental finding. Characteristically, most GISTs (> 95%) are positive for the KIT protein (CD117) by IHC staining and approximately 80%-90% of GISTs carry a mutation in the c-KIT or PDGFRA genes. Mutational analysis should be performed when planning adjuvant and neoadjuvant therapy, due to its possible resistance to conventional treatment. The arise of tyrosine kinase inhibitor has supposed a revolution in GISTs treatment being useful as adjuvant, neoadjuvant or recurrence disease treatment. That is why a multidisciplinary approach to this disease is required. The correct characterization of the tumor at diagnosis (the diagnosis of recurrences and the evaluation of the response to treatment with tyrosine kinase inhibitors) is fundamental for facing these tumors and requires specialized Endoscopist, Radiologists and Nuclear Medicine Physician. Surgery is the only potentially curative treatment for suspected resectable GIST. In the case of high risk GISTs, surgery plus adjuvant Imatinib-Mesylate for 3 years is the standard treatment. Neoadjuvant imatinib-mesylate should be considered to shrink the tumor in case of locally advanced primary or recurrence disease, unresectable or potentially resectable metastasic tumors, and potentially resectable disease in complex anatomic locations to decrease the related morbidity. In the case of Metastatic GIST under Neoadjuvant treatment, when there are complete response, stable disease or limited disease progression, complete cytoreductive surgery could be a therapeutic option if feasible.

Surgical treatment of gastric GIST with acute bleeding using laparoscopic sleeve gastrectomy: A report of two cases

“…In the Case 1, the patient was admitted to the emergency department with hematemesis and melena 48 hours following the endoscopic biopsy of a suspicious mass of the greater curvature at the gastric fundus, 30 mm in size. Conventional endoscopic forceps biopsy of GISTs is difficult and does not obtain enough tissue for a definitive diagnosis; EUS‐FNA (Endoscopic ultrasound‐guided‐fine needle aspiration biopsy) is the most established tissue sampling method . In both situations, endoscopists should pay special attention to intraoperative bleeding, perforation, or tumor cell seeding.…”

“…Conventional endoscopic forceps biopsy of GISTs is difficult and does not obtain enough tissue for a definitive diagnosis; EUS-FNA (Endoscopic ultrasound-guided-fine needle aspiration biopsy) is the most established tissue sampling method. 1 In both situations, endoscopists should pay special attention to intraoperative bleeding, perforation, or tumor cell seeding. In the Case 2, the upper gastrointestinal bleeding has been an unexpected event that worsened the conditions of a patient already admitted to the intensive care unit for cardiopulmonary complaints.…”

“…They arise from the Interstitial cells of Cajal (ICCs) that are implicated in the regulation of gut peristalsis, with a pacemaker role. GISTs are more often located in the stomach (56%) although they can arise in any portion of the digestive tract . Clinical manifestations depend on the size and the site of the primary lesion.…”

“…GISTs are more often located in the stomach (56%) although they can arise in any portion of the digestive tract. 1 Clinical manifestations depend on the size and the site of the primary lesion. Most of GISTs are asymptomatic and thus incidentally discovered during endoscopic, imaging, or surgical procedures performed for unrelated complaints.…”

Experience of Surgical Management of Gastrointestinal Stromal Tumors at a Tertiary Hospital of Nepal

“…CT was the most common diagnostic tool followed by exploratory laparotomy done for obstruction, peritonitis. CT is the gold standard for imaging that is used to characterize any abdominal mass in addition to assessing its extent and the presence/ absence of disease at a distance (GIST metastasize more frequently to the liver, omentum, and peritoneal cavity) [15]. Imaging reveals homogeneous densities in small tumors and larger tumors reveal irregular lobulated margins, mucosal ulceration, central and coagulative necrosis, hemorrhage cavitation, and heterogeneous enhancement [16].…”