Sacral chordoma, restaging Again seen is a lobulated hyperintense lesion centered at the S3 level representing the known sacral chordoma. It now measures approximately 6.3 x 3.1 x 5.2 cm in the greatest transverse, AP and craniocaudal dimensions as compared to 6 x 2.5 x 4.5 cm previously. Again seen is extension of the mass into the anterior presacral soft tissues. An additional small nodule is again seen posterior to the left sacroiliac joint that now measures approximately 3.1 x 2 as compared to 1.9 x 1 cm previously. A third satellite lobular mass posterior to the right paraspinal musculature also appears increased from the prior exam now measuring 3.9 x 3.1 cm as compared to 3.3 x 3 cm previously. Additionally, there is new abnormal marrow signal within the right sacroiliac joint particularly within the ileum posteriorly in the sacrum anteriorly. New abnormal marrow signal also affects the left sacrum. Following contrast administration, there is some peripheral enhancement of the aforementioned lesions with new enhancement of the right sacroiliac joint particularly sacrum. Additional small foci of enhancement are noted in the left gluteal musculature (image 28/52 of series 11)Edema and fluid extending along the posterior inferior right sacrum appears similar to the prior study, which may be postoperative in etiology.There is mild diffuse heterogeneity of the bone marrow which appears similar to the prior study. There is fatty atrophy of the gluteal musculature, right greater than left, appearing similar to the prior study.
Overall progression of sacral chordoma with increasing size of S3 lesion as well as increasing size of satellite lesions within the right paraspinal soft tissues. There is also new abnormal marrow signal and enhancement within the sacrum concerning for progression of disease.