Retroperitoneal sarcomas (RPS) are rare, accounting for approximately 12% of all soft tissue sarcomas [
A 65-year-old woman was admitted to our hospital because of low back pain and left posterior thigh and calf pain. When symptoms of sciatica began 2 months previously, she underwent radiography and magnetic resonance imaging (MRI) of the lumbar spine at another hospital. These showed a vertebral tumor in the lumbar spine. Both the patellar tendon and the Achilles tendon reflex were normal. The sensory exam was also normal. Although the left tibialis anterior (TA) muscle and extensor hallucis longus (EHL) muscle were manual muscle testing (MMT) grade 3, muscles other than the TA and EHL were MMT grade 5. Laboratory blood tests revealed hypoalbuminemia, anemia, and increased alkaline phosphatase and C-reactive protein. She had undergone resection of retroperitoneal DDL 5 years previously (Figure
Abdominal computed tomography (CT). (a) Enhanced CT prior to the first surgery showed a large retroperitoneal mass in the second lumbar vertebra level, which consisted of both lipomatous (yellow asterisk) and nonlipomatous (red asterisk) components. Plain CT at 8 months (b) and 3 months (c) before our first visit showed metastatic lipomatous component (red arrow) involved in the vertebral body. (d, e) CT findings at our first visit showed both lipomatous (yellow asterisk) and nonlipomatous (red asterisk) components; in addition, the metastatic lipomatous component in the vertebral body had increased and destroyed the vertebral body. Magnetic resonance image of the lumbar spine. Axial T1-weighted (f), T2-weighted (g), and enhanced T1-weighted images (h) showed the mass with a similar intensity to fat and widespread from the vertebral body to the canal space (yellow arrow).
Postoperative radiograph of the anteroposterior view (a) and lateral view (b).
Histology of the primary site-dedifferentiated liposarcoma (a, b) and well-differentiated liposarcoma components (c, d) and the metastasis (e, f). (a, c, e) Hematoxylin-eosin stain. (b, d, f) Immunohistochemistry of MDM2. There was a mixed well-differentiated and dedifferentiated component in the primary lesion (a, c). Only the well-differentiated component was seen in the spine metastasis (e). Bar = 50
Histologically, liposarcoma is classified into four subtypes: well-differentiated, dedifferentiated, myxoid/round, and pleomorphic [
Histologically, WDL and DDL are quite different. WDL, which potentiates not metastasis but recurrence, is defined as an intermediate tumor, on the borderline of benign and malignant [
In the treatment of RPS, wide resection has been recommended and leads to better survival and local control [
Adjuvant therapy, including chemotherapy and radiotherapy, should be considered because of the high incidence of recurrence and metastasis. Although the regimen of ifosfamide and doxorubicin has been reported in patients with DDL, the efficiency was low, and the development of new regimens and anticancer drugs is awaited [
The number of patients with bone metastasis, including in the spine, has been increasing, because the number of patients with cancer has been increasing. Additionally, the prognosis of these patients has improved because of improvements in early diagnosis, surgery, chemotherapy, and radiotherapy. For surgical decisions about spinal metastasis, the revised Tokuhashi score has often been used, as has the recently developed SINP score. Although the revised Tokuhashi score is dependent on primary cancer type and patient condition, the SINP score is dependent on the stability of the spine, regardless of the primary cancer or patient condition. In our case, a revised Tokuhashi score of 11 indicated that treatment was dependent on the patient, and a SINP score of 10 indicated that the operation was favored because of spinal instability. Considering that our patient had only one metastasis and her muscle weakness and sciatica worsened, we decided to perform surgery. The option of MIS allowed us to opt for surgical treatment without the frequent accompanying adverse effects. We recently reported on the clinical efficacy and safety of minimally invasive percutaneous fixation surgery with intraoperative 3-D CT computer navigation [
While it is important to carefully evaluate the clinical behavior of the primary cancer as well as the patient’s condition, the extent of surgical indication in spinal metastasis should be considered because of the development of multidisciplinary therapies and surgical techniques.
Written informed consent was obtained from the patient for the publication of this case report and any accompanying images.
The authors report no conflict of interest concerning the materials or methods used in this study or findings specified in this paper.
Jiro Ichikawa, Tetsuro Ohba, and Hiroaki Kanda are responsible for the conception and design. All the authors are responsible for to the acquisition of data. Jiro Ichikawa, Tetsuro Ohba, Hiroaki Kanda, and Hirotaka Haro drafted the article.