Contrast enhanced ultrasound demonstration of a proliferative mass in rectum wall in a patient after rectal cancer surgery

A 53-year-old man was admitted to hospital manifested with bloody stool for a month without other symptoms. Colonoscopy found a cauliflower-like mass in anterior rectal wall. The distance of the tumor lower margin from the anal verge was 5 cm. Biopsy pathology results showed adenocarcinoma.