Sigmoid carcinoma mimicking an intra-abdominal abscess in an 111In-labeled white blood cell scan.

A 61-year-old white female with ulcerative carcinoma of the sigmoid exhibited an abscess-like pattern on a white blood cell scan using 111In-oxine-labeled 'pure' granulocytes. Constant 111In activity could be seen in the tumor 0.5, 3, and 20 h after the reinjection of the labeled cells. The absence of an abscess was proven by surgery and histological investigation.