Retrorectal tumors: the choice of surgical approach based on a new classification.

Because retrorectal-presacral tumors differ in histologic origin, symptoms, and prognosis, and often involve various neighboring structures, successful treatment of this heterogeneous group of tumors depends on the surgical approach chosen and the specialist surgeons involved. We investigated whether a new classification of retrorectal tumors based on findings from CT and MRI would simplify presurgical planning. The clinical records of a series of 34 patients who underwent surgery for retrorectal tumors from 1989 to 2003 were reviewed. Two radiologists, who were blind to the patients' records, separately reviewed the preoperative CT and MRI findings and classified tumors according to whether they arose from the presacral area (Group 1), sacrum or spinal cord growing anteriorly (Group 2), or rectum growing posteriorly (Group 3). The preoperative CT and MRI findings for the retrorectal tumors yielded the information required to allow surgery to be properly planned (surgical approach and need to involve various specialist surgeons) in nearly all cases: 17 of the 18 patients (94.5%) with tumors arising from the retrorectal space, all 12 of those with tumors arising from the sacrum or spinal cord, and all four of those with rectal tumors. With the findings yielded by currently available CT and MRI techniques, retrorectal tumors can be anatomically and topographically classified preoperatively so as to allow surgery to be adequately planned in advance and thus optimize the surgical resection.