Siskind B N, Burrell M I
Gastrointest Radiol. 1986;11(3):251-3. doi: 10.1007/BF02035083.
An unusual sign of malignancy in the colon is described, consisting of an intraluminal lenticular ulcer surrounded by a meniscoid lucency of tumor. This constellation of findings was first described by Carman as a specific indicator of gastric malignancy. An aggressive ulcerating lesion with these characteristics, while rare in the colon, raises the suspicion of carcinoma.