A 78-year-old woman with coronary artery disease and congestive heart failure presents with symptoms of large bowel obstruction. Computed tomography (CT) shows a large obstructing descending colon mass with numerous hepatic and pulmonary lesions suggestive of metastatic disease. There is no evidence of bowel perforation or ischemia. Flexible endoscopy shows a large near complete obstructing carcinoma in the descending colon. Which of the following is the most appropriate next step?