We report an instance of synchronous occurrence of KIT-positive acute myeloid

We report an instance of synchronous occurrence of KIT-positive acute myeloid leukemia (AML) and gastrointestinal stromal tumor (GIST). with each other. Keywords: KIT Acute myeloid leukemia Gastrointestinal stromal tumor INTRODUCTION Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of Rabbit polyclonal to ATF2.This gene encodes a transcription factor that is a member of the leucine zipper family of DNA binding proteins.This protein binds to the cAMP-responsive element (CRE), an octameric palindrome.. the Vatalanib gastrointestinal tract. Most of the GISTs occur in the stomach (60%) jejunum and ileum (30%) and the duodenum (5%). GISTs comprise a biological spectrum of small benign Vatalanib nodules to fully malignant sarcomas [1]. The development of GIST is associated with the mutational activation of receptor tyrosine kinases namely the platelet-derived growth factor receptor-a (PDGFRA) Vatalanib or KIT [1-3]. KIT is a type III receptor protein tyrosine kinase that is involved in the development and maintenance of erythropoietic stem cells mast cells melanocytes germ cells and interstitial cells of Cajal [4]. Over-expression and/or constitutive expression of KIT alone or in conjunction with a stem cell factor (SCF) induces several solid tumors including small-cell lung carcinoma neuroblastoma pancreatic tumors and several hematological malignancies [5]. Moreover mutations involving the KIT exons Vatalanib 8 and 17 and to a less extent the KIT exons 9 and 11 have been identified in these malignancies. Previous studies have shown an association between GIST and other malignancies such as hepatocellular carcinoma adenocarcinoma mastocytosis and lymphoma/leukemia [6-11] but synchronous occurrence of GIST and leukemia has not been reported. Here we report the first case of synchronous development of KIT-positive severe myeloid leukemia (AML) and GIST. The nonrandom association and causal relationship between AML and GIST have to be investigated. CASE Record A 63-year-old female was hospitalized after experiencing exhaustion and dizziness for 2 weeks. Her physical exam was unremarkable apart from pale conjunctivae. The original laboratory tests exposed a white cell count number of 3.08×109/L a hemoglobin degree of 6.3 g/dL and a platelet count number of 80×109/L. Endoscopy exposed an ulcerofungating mass lesion around 6.0×6.0 cm in the posterior wall structure from the high body-fundus (Fig. 1). Abdominal computed tomography exposed an exophytic gastric mass and hepatic metastasis (Fig. 2). The histopathologic analysis showed differentiated malignant-cell infiltrates with epithelioid features in the myxoid stroma poorly. Immunochemical staining of the cells was positive for Compact disc117 and Compact disc 34 therefore indicating GIST (Fig. 3A-C). Nevertheless Package tyrosine kinase mutation in the gastric examples was not analyzed. The patient primarily received imatinib mesylate (400 mg/day time) to treat the metastatic unresectable tumor. Vatalanib Fig. 1 Esophagogastroenteroscopy shows an ulcerofungating mass lesion in the posterior wall of the gastric fundus. The mass is covered with normal mucosa-like submucosal tumor but it has a large ulceration at the centre. Fig. 2 Abdominal computed tomography shows an 8×7.3 cm exophytic gastric mass in the posterior wall of the gastric body containing a large area of cavitation and variable hepatic metastasis. Fig. 3 (A) Poorly differentiated malignant-cell infiltrates with epithelioid features in the myxoid Vatalanib stroma. (B) Immunohistochemical staining of cytokeratins (CK MNF116) is negative. (C) Immunohistochemical staining of KIT is positive. (D) The uniform population … On the 14th day of imatinib treatment complete blood cell count showed a white cell count of 1 1.87×109/L hemoglobin level of 8.7 g/dL and a platelet count of 29×109/L. Pancytopenia persisted even after discontinuation of imatinib and bone marrow biopsy revealed a markedly hypercellular marrow with infiltrates of myeloblasts (26%) thereby indicating AML with maturation (Fig. 3D). The karyotyping showed 39-47 XX add(4)(q12) der(5;22)(p10;q10) +der (5;22) add(12)(p11.2) -17 -19 -20 1 [19]/46 XX [1]. Immunophenotyping was positive for CD117 CD33 CD34 CD38 CD56 and CD7. We did not observe point mutations at residues D816 and N822 of KIT. Therefore the patient underwent chemotherapy with idarubicin (12 mg/m2/day) for 3 days and cytarabine (200 mg/m2/day) for 7 days but on the 18th day after the completion of chemotherapy she died of septic shock and multi-organ failure. DISCUSSION The development of GIST is believed to be associated with the.