Usefulness of hydrogel-CT for detecting and staging of rectosigmoid colon cancer

•Rectum distension using a sonographic transmission gel is convenient and safe.•Hydrogel-CT is useful to detect primary lesion of rectosigmoid colon cancer.•More accurate preoperative T/N staging can be achieved with hydrogel-CT.

PurposeTo demonstrate the usefulness of hydrogel-CT for detecting and staging of rectosigmoid colon cancer.Materials and methodsFifty-four patients with rectosigmoid colon cancers underwent routine CT without (n = 27) and with (n = 27) rectum distension using a sonographic gel. Rectum distensibility and tumor visualization were evaluated. T and N stages on CT independently recorded by two radiologists were correlated with pathologic staging. Staging accuracies were compared using Fisher’s exact test. Diagnostic performances in differentiating