Atypical Intramuscular Myxoma of the Lumbosacral Paraspinal Muscle: The First Case Report in Asian

Abstract

Intramuscular myxoma (IM) is a benign neoplasm of mesenchymal origin. We report a rare case of IM which was located in the lumbosacral paraspinal muscles. A 62-year-old female patient presented with progressive low back pain for 2 months, and the radiologic findings showed a large mass (4.0×3.5×6.5 cm) in the right lumbosacral paraspinal area. Total resection of the tumor was performed and the symptom was nearly resolved after surgery. Although the immuno-histopathological analysis was consistent with IM, there were some different findings from typical pathological characteristics of IM in this case. Firstly, the symptomatic change of the mass took relatively short time (less than 3 months), and this change was accompanied by partial calcification inside the mass. Moreover, iatrogenic interruption of paravertebral muscle by the other previous operation might be the promoting factor of the fibrous dysplasia, which can explain the pathogenesis of IM. To our knowledge, this is the eighth case of the lumbar paraspinal myxoma reported in the literatures and the first case in Asian population.

Lumbar paraspinal intramuscular myxoma: A case report

“…Most patients with these tumors present with low back pain that resolves following total tumor removal. [ 2 , 3 , 5 - 8 , 11 - 13 ] In six of the 10 previously described cases, the intramuscular myxoma was purely lumbar, as seen in our case. [ 2 , 3 , 5 - 7 , 10 ] In three cases, the lesion was lumbosacral.…”

“…[ 2 , 3 , 5 - 8 , 11 - 13 ] In six of the 10 previously described cases, the intramuscular myxoma was purely lumbar, as seen in our case. [ 2 , 3 , 5 - 7 , 10 ] In three cases, the lesion was lumbosacral. [ 8 , 12 , 13 ] One case presented with back pain progressing to paraparesis with the MR showing a thoracolumbar paraspinal intramuscular myxoma extending to the vertebral canal with spine cord compression.…”

“…Intramuscular myxomas are rarely found in the lumbar paraspinal region. [ 3 ] We were able to identify 10 similar cases in the literature with the first case dated to 1981. [ 2 , 3 , 5 - 8 , 10 , 12 - 14 ] To our best knowledge, this represents the eleventh reported case in the literature [ Table 1 ].…”

“…[ 3 ] We were able to identify 10 similar cases in the literature with the first case dated to 1981. [ 2 , 3 , 5 - 8 , 10 , 12 - 14 ] To our best knowledge, this represents the eleventh reported case in the literature [ Table 1 ]. Most patients with these tumors present with low back pain that resolves following total tumor removal.…”

“…[ 7 , 9 ] They are benign masses of mesenchymal origin composed of fibroblasts which lose the ability to produce mature collagen. [ 3 , 7 ] They occur most commonly in the heart and bony tissues (i.e., mandible and the maxilla), but rarely in the large skeletal muscles. [ 3 ] Here, we describe how a 64-year-old female presented with an intramuscular paraspinal soft-tissue myxoma and was symptom-free following total resection of the benign lesion.…”