Soft Tissue Tumors Rarely Presenting Primary in Bone; Diagnostic Pitfalls

Primary bone sarcomas represent extremely rare entities. The use of now abolished labels, such as malignant fibrous histiocytoma and hemangiopericytoma, has significantly hampered the chance of identifying specific entities. It is now accepted that a broad variety of mesenchymal malignancies most often arising on the soft tissue may actually present as primary bone lesions. A more accurate morphologic partition is justified based on availability of distinct therapeutic options. An integrated diagnostic approach represents the only way to achieve a correct classification. In consideration of the significant complexity, primary bone sarcomas should ideally be handled in the context of expert centers.     

腹膜后平滑肌肉瘤的CT,MRI表现

目的：研究腹膜后平滑肌肉瘤的CT、MRI表现。材料与方法：本组经病理证实16例,男9例,女7例。平均年龄52．8岁。16例中14例CT检查,其中5例作了强化扫描,3例MRI扫描。结果：肿瘤多见于左上腹膜后（10／16）及右侧盆底壁（3／16）。均为单发,直径＞5cm（14／16）,多呈不规则结节肿块（15／16）。CT平扫低于肌密度（14／14）,强化扫描呈周边强化（5／5）,密度不均匀（11／16）,多有侵犯特点（15／16）,无淋巴结转移。结论：发生于左上腹膜后及右侧盆底有侵犯特点的巨大肿瘤应考虑本病诊断。     

骨原发性平滑肌肉瘤

目的 了解骨原发性平滑肌肉瘤的诊断和鉴别诊断。方法 对４例骨原发性平滑肌肉瘤进行临床和病理（ＨＥ染色、免疫组织化学染色和电镜）资料观察。结果 骨原发性平滑肌肉瘤可发生在任何年龄,以中老年患者低密度影,组织学特征在免疫组织化学标记表达和电镜下改变同软组织平滑肌肉瘤,可有肿瘤组织边缘的骨化,肿瘤组织内可见破骨细胞。多数病例有车辐状结构的区域。结论 骨原发性平滑肌肉瘤和软组织平滑肌肉瘤相比,组织学上并无特殊,但诊断却较困难。常需要免疫组织化学标记和电镜的帮助方能确诊。     

Magnetic Resonance Imaging Grading System for Preoperative Diagnosis of Leiomyomas and Uterine Smooth Muscle Tumors

Study Objective

To evaluate a new magnetic resonance imaging (MRI) grading system for preoperative differentiation between benign and variant-type uterine leiomyomas including smooth muscle tumors of uncertain malignant potential (STUMPs).

Primary leiomyosarcoma of the thyroid gland with prior malignancy and radiotherapy:A case report and review of literature

BACKGROUND Leiomyosarcoma(LMS) of the thyroid gland is a rarely presented tumor that offers poor prognosis. To the best of the authors' knowledge, there currently exist only 28 known cases described in the literature(limited to English).CASE SUMMARY Herein a case is reported of a 60-year-old female patient who had an LMS of the thyroid, which was accompanied by periodic dysphonia and breathing disorder as well as the feeling of pressure in the chest and neck. At the time the disease was diagnosed, no metastases were detected. Prior to the diagnosis, the patient experienced a uterine adenocarcinoma that had been treated by surgical procedure and radiotherapy. For the LMS, a total thyroidectomy was performed,followed by radiotherapy. Since metastases were also discovered in the lungs,sternum, and femur, chemotherapy was administered as well.Immunohistochemically, the tumor cells in the thyroid indicated positively for alpha smooth muscle actin, calponin, and H-caldesmon, but were negative for CD34, p63, estrogen receptor, progesterone receptor, and Epstein-Barr virus.CONCLUSION Although the etiology of the LMS is as of yet unknown, prior malignancy and radiation should be considered as risk factors.     

How to differentiate uterine leiomyosarcoma from leiomyoma with imaging

Uterine leiomyomas, the most frequent benign myomatous tumors of the uterus, often cannot be distinguished from malignant uterine leiomyosarcomas using clinical criteria. Furthermore, imaging differentiation between both entities is frequently challenging due to their potential overlapping features. Because a suspected leiomyoma is often managed conservatively or with minimally invasive treatments, the misdiagnosis of leiomyosarcoma for a benign leiomyoma could potentially result in significant treatment delays, therefore increasing morbidity and mortality. In this review, we provide an overview of the differences between leiomyoma and leiomyosarcoma, mainly focusing on imaging characteristics, but also briefly touching upon their demographic, histopathological and clinical differences. The main indications and limitations of available cross-sectional imaging techniques are discussed, including ultrasound, computed tomography, magnetic resonance imaging (MRI) and positron emission tomography/computed tomography. A particular emphasis is placed on the review of specific MRI features that may allow distinction between leiomyomas and leiomyosarcomas according to the most recent evidence in the literature. The potential contribution of texture analysis is also discussed. In order to help guide-imaging diagnosis, we provide an MRI-based diagnostic algorithm which takes into account morphological and functional features, both individually and in combination, in an attempt to optimize radiologic differentiation of leiomyomas from leiomyosarcomas.     

Recalcitrant distal humeral non-union following previous Leiomyosarcoma excision treated with retainment of a radiated non-angiogenic segment augmented with 20 cm free fibula composite graft: A case report

BACKGROUND Leiomyosacromas in the Extremities are rare malignant smooth muscle tumors.Adjuvant radiation therapy, in combination with wide surgical excision allows the best chance of treatment. During the follow up pathological fractures are common complications that can be accompanied by Implant failure and defect situations that are most challenging in their management.CASE SUMMARY We present a case of a 52-year-old female suffering from a pathological fracture of the humeral shaft 10 yr after resection of a Leiomyosarcoma and postoperative radiotherapy. She developed implant failure after retrograde nailing and another failure after revision to double plate fixation. In a two-stage revision, the implants were removed and the huge segmental defect created after debridement was bridged by a compound osteosynthesis with nancy nails and bone cement for formation of the induced membrane. Due to the previous radiotherapy treatment,20 cm of the humeral shaft were declared devascularized but were left in situ as a scaffold. In the second stage, a vascularized fibula graft was used in combination with a double plate fixation and autologous spongiosa grafts for final reconstruction.CONCLUSION This combinatory treatment approach led to a successful clinical outcome and can be considered in similar challenging cases.     

巨大腹膜后平滑肌肉瘤伴出血1例报告并文献复习

目的:探讨腹膜后平滑肌肉瘤的临床特点、影像学表现及治疗策略,以期对类似病例的诊治提供参考。方法:回顾性分析收治的1例腹膜后平滑肌肉瘤患者临床资料,并复习相关文献。结果:患者腹部胀痛伴贫血,影像学提示中下腹部恶性肿瘤伴出血,早期行液体复苏,进一步介入栓塞,超声引导下穿刺引流,避免腹腔隔室综合征的发生;复查待瘤体缩小,贫血纠正,行完整切除肿瘤,病理诊断为平滑肌肉瘤。术后随访16个月,患者恢复良好。结论:腹膜后平滑肌肉瘤是一种罕见的恶性肿瘤,起病隐匿,易复发和转移,手术完整切除是其主要治疗方式,配合以化疗、放疗等手段综合治疗,可改善患者预后。     

Epstein-Barr Virus-Associated Smooth Muscle Tumor of the Larynx: Report of a Rare Case Mimicking Leiomyosarcoma

We present a patient (male 54 years) with a history of renal transplant who 14 years post transplantation developed a symptomatic (stridor) laryngeal Epstein Barr virus (EBV)—associated smooth muscle tumor (EBV-SMT) in the absence of concomitant disease elsewhere. Nine years post transplantation the patient developed a subcutaneous EBV-SMT tumor located on the calf. The laryngeal tumor displayed low-grade nuclear atypia and was infiltrating into the surrounding soft tissue, focally ulcerating through the overlying epithelium. Histologic features included: neoplastic cells with myoid differentiation, a component of primitive appearing small mesenchymal cells with hyperchromatic nuclei, mitotic activity, intralesional small to medium sized blood vessels and T-lymphocytes. Both the myoid and small cell mesenchymal components strongly expressed smooth muscle actin and h-caldesmon, but not desmin, cytokeratins, CD34 or S-100 protein. There was strong positive nuclear reaction for EBV-RNA on in situ hybridization (EBER). No other tumor was detected on clinical and radiological examinations and no evidence of tumor in other sites, over 8 months of follow-up, till death was detected. This case emphasizes the importance of considering this pathologic entity when solitary smooth muscle actin-expressing tumors are encountered in the larynx of immunocompromised patients.