Abstract
Myxofibrosarcoma is a type of soft tissue sarcoma, predominantly characterized by a high propensity for local recurrence, albeit demonstrating a relatively diminished risk for distant metastasis. Its prevalence is notably higher in elderly patients. Here, we present a case of a 73-year-old woman diagnosed with Myxofibrosarcoma. She was subjected to a whole-body bone scan using 99mTc-methylene diphosphonate (MDP) to survey potential bony metastasis. It revealed marked MDP accumulation with peripheral soft tissue uptake in the right lateral chest region of this patient. This imaging phenotype could potentially be attributed to the augmented vascularity within the tumor, a finding that was prominently displayed in this particular case.
Keywords: bone scan, intercostal muscle invasion, lung metastasis, myxofibrosarcoma
Figure 1.
A 73-year-old woman presented with an enlarging mass over the right posterior and lateral upper trunk regions, and also complained of right upper limb weakness. An incisional biopsy of the tumor was performed, and the pathology report identified the mass as a high-grade myxofibrosarcoma (MFS). Given her symptoms, a 99mTc-methylene diphosphonate (MDP) whole-body bone scan (WBBS) was arranged by a physician to survey for bony metastasis. The scan revealed a protruding soft tissue lesion in the lateral right chest region, with increased MDP uptake in the inferior aspect ((A), red arrow), and two MDP-avid foci in the area of the right 5th-6th ribs ((B), white arrows). A malposition of the right kidney was incidentally found. A chest CT scan revealed a large 6 × 9 × 12 cm protruding mass at the right chest wall with peripheral contrast enhancement with a central cystic-like component/multilobulated configuration ((C), red arrowhead), corresponding to the MDP uptake seen on the WBBS. It also shows invasion of the right 5th-6th intercostal muscles, but no invasion of the right 5th-6th ribs, contrary to what the WBBS was suggesting ((D), white arrowheads). There are no obvious osteolytic or osteoblastic lesions within the scan field of the CT. However, lung metastasis is also noted on the chest CT ((E), green arrow), leading to the arrangement of neo-adjuvant chemotherapy as the initial treatment. After six months, disease progression was noted, with multiple liver metastases. MFS typically arises in elderly patients, most commonly in the lower extremities, followed by the trunk. It is known to have a higher local recurrence rate (about 15~48%) but a relatively lower risk of distant metastases (near 10%) among soft-tissue tumors [1]. The treatment of MFS may involve a combination of surgical resection, radiation, chemotherapy, or targeted therapy, depending on the tumor status [2]. MRI or CT can play a crucial role in diagnosis and preoperative planning. In the literature, MFS has been reported for the detection of local tumor recurrence or metastasis using thallium-201 or FDG PET [3,4,5,6]. In our case, the MDP-avid tumor uptake and peripheral contrast enhancement/multilobulated configuration of the tumor may be related to an abundance of blood flow to the tumor. The WBBS also showed MDP-avid intercostal muscle invasion. A published article on MRI noted a multilobulated configuration of soft-tissue sarcoma, which correlates with the malignancy grade [7]. This configuration may be compatible with the biopsy results of this case. This case exemplifies the critical role of multimodal imaging in the diagnosis of myxofibrosarcoma, particularly in assessing tumor vascularity and morphology. It not only contributes to the existing literature by detailing a less common site and presentation of myxofibrosarcoma but also underscores the importance of an integrated approach to oncologic imaging in planning further treatments.
Author Contributions
Writing—original draft preparation, C.-H.L. and H.-P.C.; Writing—review and editing, H.-Y.S. and Y.-L.S. Image analysis, H.-Y.C. All authors have read and agreed to the published version of the manuscript.
Institutional Review Board Statement
Ethical review and approval were waived for this report due to its retrospective case description, which did not impact the management of the patient.
Informed Consent Statement
Written informed consent has been obtained to publish this paper.
Data Availability Statement
The original data presented in the study are available on request from the corresponding author.
Conflicts of Interest
The authors declare no conflict of interest.
Funding Statement
This research received no external funding.
Footnotes
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.
References
- 1.Spinnato P., Sambri A., Fujiwara T., Ceccarelli L., Clinca R., Medellin M.R., Paolis M.D., Donati D.M., Bianchi G. Myxofibrosarcoma: Clinical and Prognostic Value of MRI Features. Curr. Med. Imaging. 2021;17:217–224. doi: 10.2174/1573405616999200729152135. [DOI] [PubMed] [Google Scholar]
- 2.Vanni S., De Vita A., Gurrieri L., Fausti V., Miserocchi G., Spadazzi C., Liverani C., Cocchi C., Calabrese C., Bongiovanni A., et al. Myxofibrosarcoma landscape: Diagnostic pitfalls, clinical management and future perspectives. Ther. Adv. Med. Oncol. 2022;28:17588359221093973. doi: 10.1177/17588359221093973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Wu Y.C., Hsieh T.C., Kao C.H., Hsieh C.Y., Lin T.Y., Wang C.H., Lin Y.Y., Yen K.Y., Sun S.S. Thallium-201 scintigraphy of myxofibrosarcoma. Clin. Nucl. Med. 2009;34:943–945. doi: 10.1097/RLU.0b013e3181becf2a. [DOI] [PubMed] [Google Scholar]
- 4.Enomoto K., Inohara H., Hamada K., Tamura M., Tomita Y., Kubo T., Hatazawa J. FDG PET imaging of myxofibrosarcoma on the sphenoid sinus. Clin. Nucl. Med. 2008;33:421–422. doi: 10.1097/RLU.0b013e318170d51a. [DOI] [PubMed] [Google Scholar]
- 5.Ito K., Masuda-Miyata Y., Wada S., Morooka M., Yamasawa K., Hashimoto M., Kubota K. F-18 FDG PET/CT imaging of bulky myxofibrosarcoma in chest wall. Clin. Nucl. Med. 2011;36:212–213. doi: 10.1097/RLU.0b013e318208f2e0. [DOI] [PubMed] [Google Scholar]
- 6.Erdoğan E.B., Asa S., Aksoy S.Y., Ozhan M., Halac M. Appearance of recurrent cardiac myxofibrosarcoma on FDG PET/CT. Clin. Nucl. Med. 2014;39:559–560. doi: 10.1097/RLU.0000000000000420. [DOI] [PubMed] [Google Scholar]
- 7.Sedaghat S., Salehi Ravesh M., Sedaghat M., Both M., Jansen O. Configuration of soft-tissue sarcoma on MRI correlates with grade of malignancy. Radiol. Oncol. 2021;55:158–163. doi: 10.2478/raon-2021-0007. [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The original data presented in the study are available on request from the corresponding author.

