Unusual Mesenchymal Tumors of the Lower Gastrointestinal Tract: When You Hear Hoofbeats in the Night, Do Not Forget the Zebras

<b><i>Introduction:</i></b> Little information about clinical presentation of mesenchymal tumors of the lower gastrointestinal (GI) tract due to their extreme heterogeneity is available for clinical management. Usually, small solitary asymptomatic polyps are accidently found during a screening colonoscopy performed for hematochezia, abdominal pain, constipation, diarrhea, and bowel obstruction. In this case series, we illustrate our experience with mesenchymal tumors of the lower GI tract, which are a group of unusual and quite challenging lesions. <b><i>Case Presentation:</i></b> We retrospectively collected mesenchymal tumors of the lower GI tract in our institution (Fondazione IRCSS Ca’ Granda – Ospedale Maggiore Policlinico di Milano) during the last 10 years. We reviewed the histological slides, and, when necessary, we performed immunohistochemical analyses to better characterize the tumors. A total of 99 cases were identified: 45 GISTs, 42 lipomas, 4 leiomyomas, 3 Kaposi sarcomas, 1 schwannoma, 1 ganglioneuroma, 1 hemangioma, 1 inflammatory fibroid polyp, and 1 challenging case of spindle cell melanoma. We focused on the most rare entities excluding therefore all GISTs and lipomas from re-evaluation. <b><i>Conclusion:</i></b> Mesenchymal tumors of the lower GI tract represent a highly heterogeneous group of lesions encompassing GISTs, lipomas, smooth muscle tumors (leiomyoma and leiomyosarcoma), GI schwannomas, inflammatory fibroid polyps, solitary fibrous tumors, and other unusual spindle cell tumors. Immunohistochemistry and, in selected cases, molecular biology remain a useful tool which, in addition to a meticulous study of the morphology, helps the pathologist in the tangled jungle of differential diagnosis.

Vanek's tumour: a rare cause of small bowel intussusception

Adult intussusceptions which are most always caused by pathological lead points are rare and account for about 1% of all bowel obstructions and 5% of all intussusceptions. Most of them present with acute or chronic non-specific symptoms and due to which its initial diagnosis can sometimes be missed or delayed. We present the case of a 52-year-old lady who presented with intestinal obstruction caused by an ileo-ileal intussusception, caused by a peculiar tumour, inflammatory fibroid polyp (IFP).

Successful hemostasis of bleeding gastric inflammatory fibroid polyp by endoscopic treatment in a patient with severe COVID-19

The coronavirus disease-2019 (COVID-19) has rapidly become a pandemic, resulting in a global suspension of non-emergency medical procedures such as screening endoscopic examinations. There have been several reports of COVID-19 patients presenting with gastrointestinal symptoms such as diarrhea and vomiting. In this report, we present a case of successful hemostasis of bleeding gastric inflammatory fibroid polyp by endoscopic treatment in a patient with severe COVID-19. The case was under mechanical ventilation with extracorporeal membrane oxygenation (ECMO), and the airway was on a closed circuit. This indicates that COVID-19 is associated with not only lung injury but also intestinal damage, and that proper protective protocols are essential in guaranteeing the best outcomes for patients and clinical professionals during this pandemic.