Mass-forming isolated ischemic necrosis of the cecum mimicking malignancy: Clinicopathologic features of 11 cases.

Isolated ischemic necrosis of the cecum (INC) is an uncommon benign condition that occurs most often in elderly patients. The clinical presentation and radiographic findings often mimic acute appendicitis or malignancy. This study aimed to investigate the clinicopathologic features of mass-forming INC. Eleven INC patients who presented with cecal masses were identified by searching the electronic medical record system in two large academic centers. The clinical and pathological features, including symptoms, imaging, endoscopic and surgical findings, histomorphology, and follow-up, were retrospectively analyzed. The study cohort included 4 males and 7 females, with a median age 72 (range 43-87) years. Common clinical presentations included right lower quadrant abdominal pain, nausea and vomiting, and bloody diarrhea. Nine patients had hypertension and cardiovascular diseases, including coronary artery disease, congestive heart failure, atrial fibrillation, and heart valve disease. All patients had a mass in the cecum by endoscopy and/or imaging studies, clinically suspicious for malignancy. The median mass size was 5 (range 3.1-6) cm. Six patients received non-surgical treatment after the biopsy specimen proved a benign histologic pattern of ischemic necrosis. The remaining 5 patients underwent right hemicolectomy. Pathologic examination of the biopsy or resection specimens showed similar histologic changes such as mucosal denudation, ulceration, necrosis, crypt withering and loss, and lamina propria hyalinization, findings consistent with ischemic necrosis. No malignancy was identified in any case. After a median follow-up of 78 (range 3-121) months, 10 patients were still alive. Only 1 patient died and this was from other causes and 96 months later. Mass-forming INC is a rare and unique variant of ischemic colitis that occurs in elderly patients with a low flow state. It is a benign condition with a favorable prognosis. INC should be considered in patients with long-standing hypertension or cardiovascular disease who present with right lower quadrant abdominal pain and cecal mass. Biopsy of the mass with pathologic examination helps make a diagnosis, assess the disease severity, and rule out malignancy. Awareness of this rare entity is important to avoid unnecessary resections in these patients.