A 48 year old man became alarmed when he noted some bright red blood in his stool.He consulted a local physician,who palpated an indurated area (firm to touch)in the patient's rectum.Surgery was performed,and a representative section of the surgical specimen is show on low power in the accompanying photomicrograph.Which one of the following is the best diagnosis?

Question

Quizplus · Accepted Answer

The clinical history is virtually diagnostic for adenocarcinoma,the vast majority of which occur in the rectum and sigmoid colon.The photomicrograph shows a glandular neoplasm,invading into the muscularis (M),especially at the left centre of the image,where the blue glands appear to closely approach the serosal fat.

A 48 Year Old Man Became Alarmed When He Noted