チタンメッシュトレーとPCBMによる下顎骨再建を施行した類腱型エナメル上皮腫の1例

類腱型のエナメル上皮腫(desmoplastic ameloblastoma:DA)は,エナメル上皮腫の一亜型で,豊富な膠原線維の増生からなる間質と石鹸泡状のエックス線透過像を特徴とする.DAは,X線学的に境界不明瞭で,腫瘍周囲の被膜がないため切除範囲の設定が困難で,典型的なエナメル上皮腫と比較して,再発の割合が高いと考えられている.2006年9月,58歳の男性が,下顎右側臼歯部歯肉の腫脹と顎骨の膨隆にて近医より当科を紹介受診した.画像所見において,腫瘍の境界は不明瞭で,腫瘍は下顎骨下縁にまで及んでいた.生検の結果,組織学的に類腱型のエナメル上皮腫と診断された.下顎区域切除術ならびにチタンメッシュトレーと腸骨からのPCBMによる下顎骨再建を施行した.術後4年経過した現在,再発はみられていない.Desmoplastic ameloblastoma (DA) is a variant of ameloblastoma, characterized by foamy radiolucency and desmoplastic stroma. The recurrence rate of DA is thought to be higher than that of usual ameloblastoma because the fibrous capsule surrounding the tumour is not present and decision of the resection area is difficult, corresponding to the radiographically poorly-defined tumour margin. A 58-year-old man was referred to our clinic in September 2006 because of swelling of the mandible on the right side. Radiography indicated a poorly-defined lesion that expanded to the inferior border of the mandible. We carried out a biopsy and a diagnosis of DA was made histopathologically. Then, we carried out segmental mandibulectomy and mandibular reconstruction using a titanium mesh tray and PCBM from iliac bone. No signs of recurrence have been seen for 4 years after surgery

Impact of Surgical Resection and Reasons for Poor Prognosis of Pelvic Osteosarcoma Based on the Bone Tumor Registry in Japan

Pelvic osteosarcoma has a poor prognosis compared to osteosarcomas in other locations, and the reasons for this remain unknown. Surgical resection of pelvic osteosarcoma is technically demanding and often results in dysfunction and complications. In this study, we investigated the reasons underlying the poor prognosis of pelvic osteosarcoma by comparing it to femoral osteosarcoma using data from the Bone Tumor Registry in Japan. We used propensity score analysis to determine whether surgical resection of pelvic osteosarcoma improved its prognosis. We demonstrated that pelvic osteosarcoma had a poor prognosis because it occurred more often in the elderly, often had larger tumor size, and had metastasis at presentation more often in comparison to femoral osteosarcoma. These three factors were also associated with the non-surgical treatment of pelvic osteosarcoma, which also led to a poor outcome. The overall survival rate was only comparable in pelvic osteosarcoma and femoral osteosarcoma in cases treated with surgical resection. Propensity score analysis revealed that surgical treatment improved the prognosis of pelvic osteosarcoma. As such, we propose that surgical resection should be considered based on tumor stage and patient age in order to improve the prognosis of pelvic osteosarcoma

18F-Fluorodeoxyglucose Positron Emission Tomography Is Useful in the Evaluation of Prognosis in Retroperitoneal Sarcoma

Background: Retroperitoneal sarcomas are rare neoplasms that occur in the retroperitoneum. Complete surgical resection is the only effective treatment option. The prediction of prognosis by histological diagnosis has not yet been established. The purpose of this study was to identify the usefulness of [18-F] fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging for validating the prognosis of retroperitoneal sarcoma (RPS) established by histological diagnosis. Methods: We retrospectively reviewed 201 patients with RPS treated at the Osaka International Cancer Institute between 2010 and 2021. We extracted the clinical data, including standardized uptake values (SUVs), evaluated with FDG-PET, and statistically analyzed the data. Results: The median age of patients was 64 years (range, 31–85 years). A total of 101 (50.2%) patients were men, and 100 (49.8%) were women. Surgical resection was performed in 155 (77.1%) patients. On histological analysis, 75 (37.3%), 52 (25.9%), and 29 (14.4%) patients were diagnosed with dedifferentiated liposarcoma, well-differentiated liposarcoma, and leiomyosarcoma, respectively. The median survival time for patients with high maximum SUV (SUVmax) (≥4) or low SUVmax (<4) was 275.8 months and 79.5 months, respectively. Furthermore, among the patients with dedifferentiated liposarcoma, the overall survival rate for patients with high SUVmax (≥4) was significantly lower than that of those with low SUVmax (<4). Conclusions: The present study demonstrated that SUVmax calculated with FDG-PET was useful as a prognostic factor in RPS, especially in dedifferentiated liposarcoma and Grade2 RPS. To devise a treatment strategy for RPS, SUVmax during FDG-PET scan may be considered for clinical assessment