Spherogenic Stomach Ulcers

Abstract

Introduction: A 71-year-old woman with T3N2aM1b adenocarcinoma of the splenic flexure with liver and peritoneal implants, K-ras +ve, MSI- stable, underwent left sigmoid hemicolectomy for obstructive symptoms. She was treated with capecitabine, bevacizumab and SIRT using Y-90 microspheres to the right and left hepatic lobes in an interval of 2 months. Four months from the SIRT, she was experiencing intermittent epigastric pain, abdominal bloating and heartburn without any weight loss. She underwent an EGD which revealed a non-bleeding cratered gastric ulcer of 7 mm seize in the prepyloric region with diffuse moderate inflammation characterized by congestion (edema), erythema and friability in the entire stomach. The biopsy showed severe acute gastritis with ulceration, inflammatory exudate and foci of round structures consistent with radiation microspheres. There was associated reactive epithelial atypia, stromal edema, congestion, and mixed inflammation involving lymphocytes, neutrophils, and eosinophils, in the absence of malignancy. She is currently managed on pantoprazole 40 mg twice daily with night time, ranitidine 300 mg and, carafate TID with some improvement in her symptoms and we are planning to add pentoxifyline in the near future. Discussion: SIRT is associated with 3%-24% incidence of GI complications. The most common symptoms are abdominal pain, nausea/vomiting, anorexia and weight loss. Gastric ulceration with bleeding is a known but uncommon complication after SIRT. Tissue injury caused by SIRT is likely attributable to radiation rather than ischemia because the upper GI tract has an extensive collateral blood supply. These lesions are commonly refractory to medical therapy. The paradigm for treatment is similar to PUD involving acid suppression. However the suboptimal response rates in the treatment of SIRT associated ulcers may be due to the failure to address the direct radiation toxicity, as radiation has been shown to decrease gastric secretory functions by destroying parietal cells thus decreasing the acid secretion. The response to treatment with pentoxifylline, vitamin E, corticosteroids, 5-acetyl salicylic acid products, and hyperbaric oxygen are minimal. In well controlled cases partial gastrectomy has been found to be curative. In most cases progression of underlying malignancy was the primary cause of patient morbidity and mortality. SIRT induced gastritis/ulcers can be of delayed presentation. In all cases H. pylori, NSAIDs and malignancy has to be ruled out and EGD should be considered if not responding to symptomatic therapy in 3-4 weeks. Because histology is diagnostic, it becomes the onus of the endoscopist to alert the pathologists due to the sparse literature on this entity.