Primary mesenchymal chondrosarcoma of the adult lumbar spine: a case report and review of the literature
Introduction
Mesenchymal chondrosarcoma is a rare malignant tumor originating from bone or soft tissue (1,2). Morphological histology mainly shows round or ovoid malignant small cells mixed with hyaline cartilage differentiation foci, with a very high malignant potential. Young adults have the highest incidence (2), with a poor prognosis and a tendency for late local recurrence and metastasis (3). There are also reported cases of mesenchymal chondrosarcoma originating from extraskeletal tissues such as the brain and meninges (4). Only five cases of mesenchymal chondrosarcoma originating from the lumbar spine have been reported to date (Table 1) (3,5-7). To the best of our knowledge, the patient in this case is the oldest in the published literature. We present the following case in accordance with the CARE reporting checklist (available at https://tcr.amegroups.com/article/view/10.21037/tcr-22-122/rc).
Table 1
No. | Study | Sex/age, years | Tumor location | Histopathology | Immunohistochemistry | Operative treatment | Adjuvant therapy | Outcome |
---|---|---|---|---|---|---|---|---|
1 | Zibis et al., 2010 | F/9 | L5 vertebral body | Regions of primitive round or spindle-shaped mesenchymal cells alternate with well-differentiated cartilaginous tissue bands | No specific information provided | Staging tumor circumcision surgery; L4-S1 anterior/posterior spinal fusion | Neoadjuvant chemotherapy (vincristine, doxorubicin, cyclophosphamide, ifosfamide and etoposide); postoperative chemotherapy (specific information not provided); image guided radiotherapy: 5,900 cGY in 32 fractions | Alive,no recurrence for 9 years |
2 | Matsuda et al., 2006 | F/44 | L1-L2 vertebral body | The tumor tissue differentiated bidirectionally, and small round short spindle-shaped tumor cells and differentiated cartilage islands appear alternately | The tumor widely expressed vimentin and S-100 protein on cartilage island | Total resection of tumor, L1 and L2 vertebral bodies, and tail of T12 vertebral body (including surrounding soft tissues) | Chemotherapy: methotrexate, cisplatin, adriamycin, caffeine | Alive, free of disease after 5 years |
3 | Fukuda et al., 2019 | M/30 | L4 vertebral body | Infiltrative malignant biphasic differentiated tumor tissue composed of numerous well differentiated cartilaginous islands and variable numbers of poorly differentiated small cells | The CD99/MIC2 protein was immunopositive in the primary mesenchymal cells. The cartilage region positively expressed S-100 protein, and SOX-9 was expressed in both | L4 total vertebral body resection; vertebral body reconstruction | Systemic chemotherapy (no specific information provided) and local radiotherapy (not specifically mentioned) | Metastasis to scalp occurred 2 months after operation. Skin, muscle, bone and liver metastasis occurred 5 months later |
4 | Tasdemiroglu et al., 1996 | F/12 | L5 vertebral body | Mesenchymal chondrosarcoma (no specific information provided) | No specific information provided | L4-L5 laminectomy, gross tumor resection, nerve root decompression, L4-S1 segmental internal fixation | Chemotherapy: cisplatin, epirubicin, ifosfamide; radiotherapy: 5,000 R boost (not specifically mentioned) | Alive, followed up for 10 months, total neurologic improvement |
5 | Tasdemiroglu et al., 1996 | F/1 | L1-2 lamina | Poorly differentiated mesenchymal chondrosarcoma | No specific information provided | L1-5 total laminectomy, tumor resection | Chemotherapy: etoposide, ifosfamide, carboplatin, doxorubicin; radiotherapy: 750 cGy (not specifically mentioned) | Alive, followed up for 1 month, the left lower limb was slightly weak and could walk |
PMC, primary mesenchymal chondrosarcoma; F, female; M, male.
Case presentation
A 47-year-old female with intermittent dull pain in the waist for 20 years, which was aggravated by prolonged sitting or exertion, and accompanied by intermittent headache, limited mobility, and radiation of pain to both lower limbs, was admitted to our hospital for treatment due to exacerbation of the above symptoms in the prior month. Previous treatment was unknown, and there was no related family history or genetic history. Physical examination revealed tenderness to palpation in the lumbar region and restricted movement of the lumbar spine. Quadriceps muscle strength, anterior tibialis muscle strength and gastrocsoleus strength of the lower limbs were all grade 4 bilaterally. The bilateral straight leg elevation test was positive, and the bilateral Achilles tendon reflex was decreased. Laboratory and tumor marker tests indicated no significant abnormalities. Magnetic resonance imaging (MRI) scan showed bone destruction in the L1 and the adnexa, surrounded by a soft tissue mass with low signal on a T1-weighted image (T1WI) (Figure 1A) and slightly high signal on a T2-weighted image (T2WI) (Figure 1B). Enhanced MRI revealed significant enhancement of the mass (Figure 1C,1D). Abnormal striped concentration foci in the L1 vertebral body was detected by technetium 99 m-methylene diphosphonate (99 m Tc-MDP) bone scanning (Figure 2). Vertebral bone biopsy under local anesthesia was performed under the guidance of a C-arm X-ray machine to facilitate diagnosis and subsequent treatment. The biopsy showed short spindle-shaped tumor cells with eosinophilic cytoplasm, indistinct cytosolic boundaries and spindle-shaped, ovoid nuclei, which were enriched with branching vessels. Immunohistochemical staining of tumor cells indicated expression of TLE1, INI1, and BCL-2 and partial expression of CD117 and CD99 (Figure 3), suggesting a low-grade mesenchymal tissue-derived soft tissue tumor. Because a punch specimen was obtained by biopsy and the phenotype of the tumor could not be clarified, surgical gross total resection was performed.
The patient underwent posterior lumbar surgery with a dorsal median incision centered at the spinous process from T11 vertebra to L3. A layer-by-layer incision of the skin and subcutaneous tissue was made to the lumbar dorsal fascia and through the left and right spinous process, stripping the exposed lamina to the facet joints and transverse process. After determining the entry point for and inserting pedicle screws, L1 total laminectomy was performed. It was found that the L1 left pedicle had been destroyed by the tumor and that the spinal cord and L1 left nerve root were encased in tumor tissue. After careful separation, the T12/L1 and L1/L2 intervertebral discs were completely removed. To prevent local recurrence and metastasis, we use the lower endplate of T12 and the upper endplate of L2 as the boundaries and osteotomized the L1 vertebral body bilaterally; we closely protected the ventral aorta and the anterior longitudinal ligament, carefully separated the surrounding tissues and resected the L1 vertebral body and the surrounding tumor tissue in blocks. Intraoperatively, the spinal cord was seen to be well distended, and no significant compression was detected. An artificial vertebral body was placed in the intervertebral space and adjusted and installed well; the internal fixation was reinforced, and the spinal cord was checked again, with no compression noted. After extensive flushing with saline and tight hemostasis, two drains were placed, the incision was closed layer by layer, and the patient was returned to the ward after stabilization of vital signs.
According to pathological examination of the specimen resected, there was no tumor infiltration in the resection margins, demonstrating that the tumor was extensively resected. Postoperative histopathological examination revealed that the tumor tissue consisted of undifferentiated small round cells and insular hyaline cartilage, showing typical bidirectional differentiation. Immunohistochemical staining indicated tumor cell expression of NKX2.2, BCL-2+, SATB-2+, and Ki67 (10%+), partial expression of CD117 and CD99, and no expression of vimentin, S-100, STAT6, H3F3A, MyoD1, Myogenin, SOX-10 (Figure 4). These immunohistochemistry results are atypical of mesenchymal chondrosarcoma; in general, mesenchymal chondrosarcomas express S-100 in the cartilage region and vimentin, CD99, and CD57 in small cells (6). Finally, the case was diagnosed as mesenchymal chondrosarcoma based on various examinations and histopathological findings. After the operation, the patient was stable and could walk on crutches when discharged from the hospital. Radiotherapy was planned after one month, but the patient refused due to financial reasons. During the year of postoperative follow-up, the patient was doing well, was pain-free, showed no corresponding symptoms, and presented no metastasis. Furthermore, the artificial vertebral body and the metal fixator remained in place, with no signs of loosening or slipping on postoperative and follow-up X-rays (Figure 5). We will continue to follow up with this patient.
Ethical statement
All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.
Discussion
Mesenchymal chondrosarcoma is an extremely rare, invasive variant of chondrosarcoma (1,8), accounting for 3% to 10% of chondrosarcomas and 0.2% to 0.7% of malignant bone tumors (9). Lightenstein et al. (1) reported the first case of mesenchymal chondrosarcoma in 1959. The majority of cases involve patients in the second or third decade of life, with an average age of 25 years and no sex differences (5). The most common sites of involvement are the maxilla and mandible, but mesenchymal chondrosarcoma may also occur in the spine, ribs, pelvis, humerus, and extraosseous tissues (5). Chondrosarcomas originating in the lumbar spine are rare, as is mesenchymal chondrosarcoma. Hence, mesenchymal chondrosarcoma originating in the lumbar spine is even more rare (1) and worth reporting.
In general, patients with mesenchymal chondrosarcoma seek medical attention due to radicular pain and numbness caused by compression of the lesion. However, a diagnosis of mesenchymal chondrosarcoma is commonly delayed due to the nonspecific clinical manifestations and signs. In this case, the patient had a 20-year history of low back pain. In addition, of the 5 cases found in a literature review, two had a 1-month history of pain at the lesion site (3,7), one had a 9-month history of nausea, lumbar pain, and left flank pain (5), one had a 3-year history of low back pain (6); the remaining case had a 4-month history of back pain (7).
Although imaging examinations may provide a basis for the diagnosis of mesenchymal chondrosarcoma, it is difficult to distinguish it from other types of tumors (9). On X-ray, mesenchymal chondrosarcomas typically appear as a soft tissue mass or osteolytic lesion with indistinct or well-defined borders, and sclerosis is often present. On MRI, most mesenchymal chondrosarcomas are isointense on T1WI and T2WI and tend to be lobulated with well-defined borders (10). The mass in this case was hypointense on T1WI and hyperintense on T2WI, which is quite different from the common isointense manifestations. Overall, imaging examinations are not reliable for diagnosing mesenchymal chondrosarcoma because the imaging manifestations are not specific, and Ewing sarcoma, neurofibroma, and schwannoma should also be considered in diagnosis (9).
Histopathologically, mesenchymal chondrosarcomas are characterized by bidirectional differentiation of tumor cells consisting of alternating small round or spindle-shaped undifferentiated mesenchymal cells and islands of hyaline cartilage (9). The cartilaginous and undifferentiated areas are well defined or intertwined as they migrate, and hemangiopericytoma-like changes can be seen in the undifferentiated areas. Immunohistochemical detection of corresponding biomarkers can help to distinguish mesenchymal chondrosarcomas from other tumors (9). Most mesenchymal chondrosarcomas express vimentin, CD57, CD99, and SOX-9 in small cells and S-100 protein in cartilage regions. SOX-9 is a discriminative marker that is positive in both cartilage areas and small cells and can be used to distinguish mesenchymal chondrosarcoma from other small cell tumors. Nevertheless, it is not a specific marker and can be detected in other cartilaginous tumors (6). The absence of MyoD1 and Myogenin expression can be used to differentiate rhabdomyosarcoma from mesenchymal chondrosarcoma. STAT6 is thought to be a highly sensitive marker for solitary fibrous tumor (SFT), and the absence of STAT6 expression can be utilized to distinguish mesenchymal chondrosarcoma from SFT (11). Overall, diagnosis of mesenchymal chondrosarcoma is difficult, and definitive diagnosis is mainly based on histopathological examination, with immunohistochemistry serving as an auxiliary tool.
As mesenchymal chondrosarcoma has a high recurrence and metastasis rate, treatment should be carefully selected. Kawai et al. (12) considered an insufficient surgical margin to be the only independent poor prognostic factor for local recurrence and distant metastasis in patients with chondrosarcoma. In multivariate analysis, surgical margins and tumor grade are statistically significant factors for local recurrence and systemic spread (13). When surgical resection is selected for mesenchymal chondrosarcoma, the extent of tumor resection is reportedly related to overall postoperative survival. At present, complete tumor resection plus stable spinal fixation is the primary choice for treating mesenchymal chondrosarcoma (14). Therefore, total vertebrectomy was performed for our patient to obtain as much total resection of the tumor as possible, and artificial vertebral body replacement was used to enhance spinal stability. Although clinical data and detailed guidelines on the efficacy of radiotherapy for mesenchymal chondrosarcoma are currently lacking, the efficacy of radiotherapy is debatable (9). However, Kawaguchi et al. (15) found that postoperative adjuvant radiotherapy reduced the rate of local recurrence. Four of the five patients with lumbar mesenchymal chondrosarcoma identified in our review received postoperative radiotherapy; one developed scalp metastasis two months after surgery (6), and none of the remaining three developed local recurrence and metastasis during postoperative follow-up (3,7). Thus, we recommend postoperative adjuvant radiotherapy.
Conclusions
Primary mesenchymal chondrosarcoma (PMC) has no specific clinical manifestations and imaging features, and more attention should be given to this disease in clinical work. Furthermore, PMC has a high rate of local recurrence and distant metastasis. Patients should be followed up regularly, and intervention should be actively implemented. Based on the treatment and prognosis of cases to date, total tumor resection combined with postoperative adjuvant radiotherapy is recommended to prevent disease progression and recurrence.
Acknowledgments
We thank Chi Dong and Furong Tian for their help with the histopathological examination, and we would like to thank the highly qualified native English-speaking editors at Springer Nature Author Services for their help with the English language, grammar, punctuation, spelling, and overall style of our manuscript.
Funding: This study was supported by
Footnote
Reporting Checklist: The authors have completed the CARE reporting checklist. Available at https://tcr.amegroups.com/article/view/10.21037/tcr-22-122/rc
Peer Review File: Available at https://tcr.amegroups.com/article/view/10.21037/tcr-22-122/prf
Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tcr.amegroups.com/article/view/10.21037/tcr-22-122/coif). All authors report that this study was supported by the Xigu District Science and Technology Support Program Project, Lanzhou City, Gansu Province (No. 2018-3-79). The authors have no other conflicts of interest to declare.
Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.
Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.
References
- Lightenstein L, Bernstein D. Unusual benign and malignant chondroid tumors of bone. A survey of some mesenchymal cartilage tumors and malignant chondroblastic tumors, including a few multicentric ones, as well as many atypical benign chondroblastomas and chondromyxoid fibromas. Cancer 1959;12:1142-57. [Crossref] [PubMed]
- Dantonello TM, Int-Veen C, Leuschner I, et al. Mesenchymal chondrosarcoma of soft tissues and bone in children, adolescents, and young adults: experiences of the CWS and COSS study groups. Cancer 2008;112:2424-31. [Crossref] [PubMed]
- Zibis AH, Wade Shrader M, Segal LS. Case report: Mesenchymal chondrosarcoma of the lumbar spine in a child. Clin Orthop Relat Res 2010;468:2288-94. [Crossref] [PubMed]
- Rushing EJ, Armonda RA, Ansari Q, et al. Mesenchymal chondrosarcoma: a clinicopathologic and flow cytometric study of 13 cases presenting in the central nervous system. Cancer 1996;77:1884-91. [Crossref] [PubMed]
- Matsuda Y, Sakayama K, Sugawara Y, et al. Mesenchymal chondrosarcoma treated with total en bloc spondylectomy for 2 consecutive lumbar vertebrae resulted in continuous disease-free survival for more than 5 years: case report. Spine (Phila Pa 1976) 2006;31:E231-6. [Crossref] [PubMed]
- Fukuda A, de Castro Oliveira DL, Fernandes Joaquim A, et al. Vertebral body chondrosarcoma with metastasis to the scalp. BJR Case Rep 2018;5:20180037. [Crossref] [PubMed]
- Tasdemiroglu E, Bagatur E, Ayan I, et al. Primary spinal column sarcomas. Acta Neurochir (Wien) 1996;138:1261-6. [Crossref] [PubMed]
- Di Lorenzo N, Palatinsky E, Artico M, et al. Dural mesenchymal chondrosarcoma of the lumbar spine. Case report. Surg Neurol 1989;31:470-2. [Crossref] [PubMed]
- Chen S, Wang Y, Su G, et al. Primary intraspinal dumbbell-shaped mesenchymal chondrosarcoma with massive calcifications: a case report and review of the literature. World J Surg Oncol 2016;14:203. [Crossref] [PubMed]
- Amir D, Amir G, Mogle P, et al. Extraskeletal soft-tissue chondrosarcoma. Case report and review of the literature. Clin Orthop Relat Res 1985;219-23. [PubMed]
- Doyle LA, Vivero M, Fletcher CD, et al. Nuclear expression of STAT6 distinguishes solitary fibrous tumor from histologic mimics. Mod Pathol 2014;27:390-5. [Crossref] [PubMed]
- Kawai A, Healey JH, Boland PJ, et al. Prognostic factors for patients with sarcomas of the pelvic bones. Cancer 1998;82:851-9. [Crossref] [PubMed]
- Bergh P, Gunterberg B, Meis-Kindblom JM, et al. Prognostic factors and outcome of pelvic, sacral, and spinal chondrosarcomas: a center-based study of 69 cases. Cancer 2001;91:1201-12. [Crossref] [PubMed]
- Liu S, Zhou X, Song A, et al. Surgical treatment of metastatic mesenchymal chondrosarcoma to the spine: A case report. Medicine (Baltimore) 2020;99:e18643. [Crossref] [PubMed]
- Kawaguchi S, Weiss I, Lin PP, et al. Radiation therapy is associated with fewer recurrences in mesenchymal chondrosarcoma. Clin Orthop Relat Res 2014;472:856-64. [Crossref] [PubMed]