Radiology of sacrococcygeal chordoma. Difficulties in detecting soft tissue extension.

Plain radiographs of seven patients with sacrococcygeal chordomas showed sacral destruction, enlarged sacral neural foramina, and, usually, a presacral mass. Conventional tomograms clarified these bone abnormalities, which were often poorly visible on the plain radiographs. Two radionuclide bone scans showed increased peripheral uptake around the lesion, and one showed decreased uptake in the area of destroyed bone. Angiograms demonstrated only vessel displacement, and barium enemas showed only displacement of bowel by large soft tissue masses. Five myelograms were normal. Adequate surgical treatment of sacral chordomas requires a wide radical resection that avoids contaminating the wound with tumor. Therefore, thorough preoperative radiologic evaluation of the anatomic extent of a chordoma is essential. Although computed tomograms in three patients provided the best delineation of the total extent of bone and soft tissue involvement, tumor extension into gluteal muscles and other tissues eluded radiographic detection. The widespread infiltrative growth pattern along soft tissue planes and nerves and into vessels, undetectable by the above listed studies, mandates a cautious approach and a wide surgical margin, to prevent wound contamination and subsequent recurrence.