# Myofibrosarcoma Mimicking Inflammatory Lesion of Temporomandibular Joint--Case Presentation
## 3 Results  
The 75-year-old male was referred to the Department of Maxillofacial Surgery Medical University of Lodz, Poland, due to weight loss caused by severe pain in the left temporomandibular joint and restricted mouth opening for four years. The patient was burden with ischemic heart disease and benign prostatic hyperplasia. In the intra- and extra-oral examination, a restriction of mouth opening to 10 mm was noted (Figure 1), also our patient presented with insufficient lateral movement of the mandible. The MRI of TMJ was performed and described by the radiologist as chronic arthritis and inflammation of the surrounding tissue (33 \(\times\) 18 \(\times\) 22 mm). Lateral pterygoid muscle, temporal muscle and masseter were involved as well (Figure 2). A consultation with a rheumatologist was commissioned and scintigraphy was performed--it was described as a degenerative-inflammatory lesion, confirming the primary diagnosis as chronic arthritis. The patient qualified for total temporomandibular joint replacement with an individual prosthesis. Before the surgery, CT with 3D reconstruction was performed to design a prosthesis. The mandibular fossa was made of UHMW-PE and the condylar part of titanium. Under general anesthesia, alloplasty of the TMJ was performed (Figure 3). Glenoid fossa, discus, condyle process as well as part of the mandible ramus and part of pterygoid muscle were resected. Postoperatively, the improvement of mandible movement was seen. The patient presented slight facial nerve paresthesia--intense rehabilitation (massage, kinesin therapy, Kinesio Taping) was administered. Figure 1: Patient presenting mouth restriction to 10 mm. Postoperative material was histopathologically examined and described as follows: \"Two histological patterns are seen in that case. The dominating one is the low-grade myxofibrosarcoma component with uniformly myxoid matrix, moderate cellularity, mild cellular atypia and prominent, sometimes curvilinear, elongated vessels (Figure 4). High-grade-like areas are very cellular with bizarre, sometimes multinucleated giant cells with abundant eosinophilic cytoplasm resembling myoid cells (Figure 5). Many nuclei are irregularly shaped. There are not foci of necrosis. The mitoses are infrequent. The lack of these two last features do not allow to classify that tumor as high-grade. That is why the term intermediate-grade would be more appropriate. An immunohistochemical analysis for this case was nonspecific. It is positive for s100p, CD68 and CD34. Ki-67 index was low.\"  
Figure 3: First operation of the patient—alloplasty of the TMJ. An individual prosthesis was prefabricated (the mandibular fossa was made of UHMW-PE and the condylar part was made of titanium). Glenoid fossa, discus, condyle process as well as part of the mandible ramus and part of pterygoid muscle were resected. Figure 2: Imaging examination presenting the lesion (MRI on the left and scintigraphy on the right). Chronic arthritis and inflammation of surrounding tissue (\(33\times 18\times 22\) mm). Lateral pterygoid muscle, temporalis muscle and masseter were involved. The patient was qualified for reoperation (Figure 6). Under general anesthesia extended resection of glenoid fossa and subtemporal fossa was performed. Supraomohyoid lymphadenectomy was also performed during the surgery and, in palpative examination, enlarged lymph nodes were found. The prosthesis was removed and a titanium part was sterilized intraperitoneally. A new UHMW-PE part was designed before surgery. The procedure was performed without complication. The patient was then referred for adjuvant radiotherapy (Figure 7). After the course, PET-CT was performed. No metastasis or local surgical  
recurrence was noted. The patient remains under the control of the clinic and has stayed disease-free for over five years (Figure 8). Figure 6: Reoperation procedure. A submandibular incision was performed (**A**) and an individual UHMW-PE implant was removed (**B**) and sterilized.