Blocked by a Ring: A Case of Gastric Linitis Plastica Presenting as Large Bowel Obstruction Secondary to Rectal Stenosis

Metastatic gut lesions from primary gastric carcinoma occur via hematogenous, lymphatic, or peritoneal seeding. We report an unusual case of large bowel obstruction secondary to rectal stenosis due to metastatic signet ring cell gastric cancer. A 61-year-old woman with a history of 8 weeks' duration of alternation in bowel movements presented with symptoms of bowel obstruction. Computed tomography revealed rectal wall thickening, and sigmoidoscopy demonstrated edematous and fibrotic rectal mucosa. Superficial biopsies were negative for malignant disease. Because of worsening of obstructive symptoms, an emergent surgical diversion was performed. Surgical biopsies were consistent with poorly differentiated adenocarcinoma. Gastroscopy established diagnosis of gastric adenocarcinoma with signet ring type cells. Rectal stenosis on examination and demonstration of rectal wall thickening on imaging should raise suspicion for Schnitzler's metastasis, and an upper endoscopy should be performed.