J Korean Orthop Assoc.
2022 Dec;57(6):497-504. 10.4055/jkoa.2022.57.6.497.
A Comparative Analysis of Myxofibrosarcoma and Myxoid Liposarcoma
- Affiliations
-
- 1Department of Orthopaedic Surgery, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea
- 2Departments of Radiology, Pusan National University Hospital, Busan, Korea
- 3Departments of Pathology, Pusan National University Hospital, Busan, Korea
- KMID: 2537063
- DOI: http://doi.org/10.4055/jkoa.2022.57.6.497
Abstract
- Purpose
Both myxofibrosarcoma and myxoid liposarcoma have similar characteristics and both commonly occur at the extremities in the elderly. While there are some differences between the two clinical entities, they both have similar clinical and radiographic features. Therefore, in this study, we attempted to identify features that help the diagnosis of the two tumors by comparing their radiographic features using magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET-CT). In addition, we compared features, such as the biopsy results, clinical manifestations, local recurrence, and metastasis.
Materials and Methods
A retrospective cohort study was performed on 44 patients (21 myxofibrosarcoma patients and 23 myxoid liposarcoma patients) who had been diagnosed with myxofibrosarcoma or myxoid liposarcoma and underwent surgery between January 2007 and January 2020. Findings that helped the diagnosis of each tumor were identified by comparing preoperative MRI and PET-CT and the clinical features of the 44 patients.
Results
In the group of 44 patients, the average patient age was 65.76 years for myxofibrosarcoma and 51.83 years for myxoid liposarcoma (p=0.003). The average tumor size was smaller for myxofibrosarcoma patients at 5.5 cm vs. 11.3 cm for myxoid liposarcoma (p=0.006). The presence of fascial tail sign on MRI was significanty different between the two tumors, found in nine myxofibrosarcoma patients and not seen in any myxoid liposarcoma patients (p=0.001). A postoperative positive margin was found in 9 myxofibrosarcoma cases and 3 myxoid liposarcoma cases (p=0.047). The maximum standardized uptake value (SUVmax) on PET-CT and local recurrence were higher in the case of myxofibrosarcoma, but this difference was not clinically significant.
Conclusion
Myxofibrosarcoma is smaller than myxoid liposarcoma but has a much higher local recurrence rate, which could be related to higher postoperative positive resection margins. The SUVmax value on preoperative PET-CT had a higher uptake in the case of myxofibrosarcoma which could help distinguish the two tumors before surgery. In addition, the fascial tail sign was found more frequently in the case of myxofibrosarcoma on preoperative MRI (p=0.001).
