This model is the left thigh muscle rendering of a 65-year-old male with left thigh myxoid fibrosarcoma. At the time of diagnosis, the patient had metastases to his lungs. The patient therefore underwent neoadjuvant radiotherapy, surgery, and adjuvant chemotherapy and was found to have an intermediate grade lesion at the time of diagnosis. The patient is still living with the metastatic disease at 2.5 years since diagnosis. This is an STL file created from DICOM images of his CT scan which may be used for 3D printing.
Myxoid fibrosarcoma (or myxoid MFH) is the most common subtype of MFH, at about 10%-20% of cases. Clinically, the tumor presents as a deep, slow-growing, painless mass. It is located more commonly in the lower extremities and retroperitoneum. Imaging on MRI demonstrates a mass with low signal intensity on T1-weighting imaging, and high signal intensity on T2-weighted imaging. On histology, a myxoid background is present with a storiform (or cartwheel) pattern seen on low-power imaging, seen in fibrosarcomas. A “myxoid background” is composed of a clear, mucoid substance. Treatment includes radiation, wide surgical resection, and chemotherapy in selected cases. However, the 5-year survival is 50%-60% depending on size, grade, depth and presence of metastasis.
The term “malignant fibrous histiocytoma” was coined in the 1960s by Margaret R. Murray when histology a sarcoma demonstrated an appearance like histiocytes, with characteristics of phagocytosis and a pleomorphic pattern. With further research, this entity was identified to have a wider range of appearances with a fibrous characteristic. Today, these sarcomas are known as “pleomorphic sarcomas.”
Recently, a change in the understanding of soft tissue tumors has purported that MFH is not a specific type of cancer, but a common morphologic pattern shared by unrelated tumors. One school of thought states that this morphologic pattern is shared by tumors as a common final pathway in cancer progression whereas another school of thought believes that true pleomorphic sarcomas are the result of a transformation from mesenchymal stem cells. Future research into understanding the pathway of these sarcomas and progression will help to target specific therapies and, hopefully, eventual cures.
This model was created from the file STS_022.