Dramatic response of a gastrointestinal stromal tumor to neadjuvant imatinib therapy

Abstract

Gastrointestinal stromal tumors (GISTs) are the most common sarcoma of the alimentary tract and are believed to derive from the interstitial Cell of Cajal. Imatinib mesylate (Gleevec ® ; Novartis, Basel, Switzerland) has revolutionized the treatment of GISTs and is generally used in the metastatic and adjuvant settings. We report the case of a 61-year old man who was treated with neoadjuvant imatinib for a massive gastric GIST with the hope of avoiding a potential multi-visceral resection. Case presentationA 61-year old man presented with a left upper quadrant abdominal mass after experiencing several intermittent episodes of nausea, vague abdominal discomfort, and mild acid reflux. He also reported a nine kilogram weight loss over the prior six to eight months. Physical examination revealed a large mass in his upper abdomen.Abdominal computed tomography (CT) revealed a 21 × 12 cm heterogeneous mass occupying his mid and left upper quadrants (Figure 1). Based on its location and imaging characteristics, the mass was hypothesized to be a GIST. The differential also included lymphoma, retroperitoneal sarcoma, and, less likely, a pancreatic neoplasm. To establish the diagnosis, an endoscopic ultrasound was performed and a core biopsy of the mass was obtained. The pathology of the core biopsy classified the mass as a spindle cell neoplasm that stained positive for CD117, consistent with a GIST.Given the size and location of the lesion at the time of initial evaluation, resection of the mass would likely have necessitated a multi-visceral resection. Based on recent reports of effective preoperative imatinib therapy, a trial of neoadjuvant imatinib was felt to be the optimal treatment strategy to down-stage the tumor and minimize the extent of resection [1].The patient was treated with imatinib and tolerated the therapy well, with the exception of developing mild periorbital edema, the most commonly reported side effect of imatinib [2]. He was followed with CT scans performed at two-month intervals. The mass measured 21 × 12 cm on initial imaging. Subsequent measurements were 16.9 × 9.1 cm, 12.2 × 9.6 cm, and 10 × 8 cm (Figure 2) at two, four, and six month intervals, respectively. Upon reviewing the patient's imaging and clinical course after six months of treatment, it was felt that resection was appropriate. Further, there was concern regarding the development of secondary resistance to imatinib.

Spontaneous perforation of jejunal gastrintestinal stromal tumour (gist). Case report and review of literature

“…Chronicity is a rule. Acute atypical presentation includes hemorrhage and perforative peritonitis [1-10]. Preoperative imaging modalities like contrast enhanced abdominal computerized tomography (CT) aids in diagnosis [8].…”

“…Endoscopy demonstrates smooth, mucosa-lined protrusion of the bowel wall which may or may not show signs of bleeding or ulceration. Endoscopic ultrasound with guided fine-needle aspiration is diagnostic for primary lesions in 89% of the cases [8-10]. However, the relative usefulness of images depends on the site, duration and suspicion of GIST in patients presenting with undiagnosed abdominal lumps.…”

“…However, the relative usefulness of images depends on the site, duration and suspicion of GIST in patients presenting with undiagnosed abdominal lumps. The decisive diagnosis rests on the pathological and immunohistological tests [2,5-10]. Histopathologically GISTs are composed of spindle (70%), epithelioid and round cell or an admixture [6,8].…”

“…Histopathologically GISTs are composed of spindle (70%), epithelioid and round cell or an admixture [6,8]. Similarities with histological picture of gastrointestinal leiomyosarcoma, leiomyoblastoma and poorly differentiated carcinomas may cause diagnostic dielemma, Immuno-histochemical assays for CD117 antigen (KIT) is the mainstay for diagnosis [9,10]. …”

Spontaneous perforation of jejunal gastrointestinal stromal tumour presenting with multiple intraperitoneal abscess cavities: a case report and review of literature

“…12,13 Complete surgical resection entails 48-65% five-year survival. 2 Perforation of the tumor lowers the five-year survival to 24%, probably due to peritoneal dissemination.…”