Mutational profile of KIT and PDGFRA genes in gastrointestinal stromal tumors in Peruvian samples.

INTRODUCTION: Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms usually caused by somatic mutations in the genes KIT (c-kit) or PDGFRA. Mutation characterization has become an important exam for GIST patients because it is useful in predicting the response to the inhibitors of receptor tyrosine kinase (RTK). OBJECTIVES: The aim of this study was to determine the frequency of KIT and PDGFRA mutations in 25 GIST samples collected over two years at two national reference hospitals in Peru. There were 21 samples collected from the Instituto Nacional de Enfermedades Neoplásicas (INEN, national cancer center) and 4 samples collected from Hospital A. Loayza. METHODS AND MATERIALS: In this retrospective study, we performed polymerase chain reaction (PCR) amplification and deoxyribonucleic acid (DNA) sequencing of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) genes in 20 FFPE (formalin-fixed, paraffin-embedded) and 5 frozen GIST samples. RESULTS: We report 21 mutations, including deletions, duplications, and missense, no mutations in 2 samples, and 2 samples with no useful DNA for further analysis. Eighty-six percent of these mutations were located in exon 11 of KIT, and 14 % were located in exon 18 of PDGFRA. CONCLUSIONS: Our study identified mutations in 21 out of 25 GIST samples from 2 referential national hospitals in Peru, and the mutation proportion follows a global tendency observed from previous studies (i.e., the majority of samples presented KIT mutations followed by a minor percentage of PDGFRA mutations). This study presents the first mutation data of the KIT and PDGFRA genes from Peruvian individuals with GIST.

Una gran Brunneroma como causa inusual de hemorragia digestiva / Big Brunneroma as unusual cause of intestinal bleeding

Nosotros reportamos un gran hamartoma de las glándulas de Brunner (8 x 2.5 x 2 cm) que se presento en una mujer de 75 años con una historia de 10 días de melena. El estudio endoscópico identificó una tumoración ovoide, móvil que ocupaba parcialmente la luz duodenal. La biopsia endoscópica fue negativa porque el tumor estuvo localizado completamente en la submucosa. En el acto operatorio, un tumor polipoideo fue encontrado en la segunda porción del duodeno por encima de la ampolla de Vater. Se revisan las características clínicas, endoscópicas, radiológicas, histológicas y quirúrgicas del hamartoma de las glándulas de Brunner.

We reported a great Brunner's gland hamartoma (8x2.5x2 cm) which was present in a seventy-five year old woman with a1O-day history of melena.Gastroduodenoscopy showed an ovoid and movible tumor located within the duodenum. The endoscopic biopsy was negative because the tumor was totally in the submucosa. During surgery, a polypoid tumor was found in the second portion of the duodenum above the ampulla of Vater. The clinical, endoscopical, radiological, histological, and surgical features of Brunner'sgland hamartoma, are reviewed.

[BIG BRUNNEROMA AS UNUSUAL CAUSE OF INTESTINAL BLEEDING] / Una gran "Brunneroma" como causa inusual dehemorragia digestiva.

We reported a great Brunner's gland hamartoma (8x2,5x2 cm) which was present in a seventy-five year old woman with a 1 0-day history of melena.Gastroduodenoscopy showed an ovoid and movible tumor located within the duodenum. The endoscopic biopsy was negative because the tumor was totally in the submucosa. During surgery, a polypoid tumor was found in the second portion of the duodenum above the ampulla of Vater.The clinical, endoscopical, radiological, histological, and surgical features of Brunner's gland hamartoma, are reviewed.