MR imaging evaluation of recurrent tumor in patients after abdominoperineal resection for rectal cancer

Presacral recurrence of rectal carcinoma after anteroposterior resection is a common complication. Ten patients with recurrences suspected from CT findings were evaluated with MR imaging. The tumor and the adjacent sacrum and/or organs were surgically removed in most patients within 1-2 weeks after MR imaging. In seven cases the tumors were confined to the presacral space. In two patients there was extension into the sacrum, and in one patient the tumor involved the pelvic side wall and extended into the proximal femur. On T2-weighted images there was no significant difference in signal intensity between tumor and benign postsurgical reaction. MR imaging proved very useful in determining the extent of tumor recurrence