Sonographic findings of hibernoma. A report of two cases

We present 2 cases of hibernoma, a rare lipomatous tumor arising from brown fat tissue. In each case, a hyperechoic mass in comparison to surrounding musculature combined with elevated vascularization was highly suggestive of a liposarcoma. As a rule, malignancy cannot be excluded safely by imaging modalities, and a preoperative biopsy should be performed. Although rare, hibernomas should be considered in the differential diagnosis of lipomatous soft-tissue tumors.     

Endoprosthetic replacement of the humerus combined with trapezius and latissimus dorsi transfer: a report of three patients

Introduction To improve the functional outcome after proximal and/or total humerus replacement, we combined the surgical procedures described by Bateman and Gerber.Materials and methods In three patients after wide tumor resection, endoprosthetic replacement with a modular tumor endoprosthesis (MUTARS System) was performed. In addition to a capsular and muscular reconstruction using the Trevira tube, a trapezius transfer onto the Trevira tube in combination with a latissimus dorsi transfer onto the Trevira tube was performed. The patients were immobilized for 6 weeks after surgery with an abductor cast.Results After a follow-up of 1 year, there was no significant improvement of the shoulder function in comparison with patients who did not undergo the combined muscle transfer (control group n=16: mean abduction 37.5°; mean anteversion 35.0°; mean internal rotation 15.2°; mean external rotation 25.2°).Conclusion In our patients, the combination of the Gerber and the Bateman procedures did not improve the shoulder function in patients with proximal and/or total humerus replacements. Therefore, the functional results do not justify two separate approaches and a prolonged operation time.     

The multicentric epitheloid hemangioendothelioma of bone: a case example and review of the literature

Epitheloid hemangioendothelioma of bone is a rare primary bone malignancy. Diagnosis can be difficult for physicians who are not experienced with bone neoplasms. We also had difficulties in diagnosis and treatment in one of our patients with a multicentric epitheloid hemangioendothelioma involving the pelvis, left femur, and left tibia. We recommend a complete skeletal survey with magnetic resonance imaging because it can reveal previously undetected lesions on conventional radiographs. We performed an extraarticular resection of the hip joint including the spina iliaca anterior inferior, resection of the femur, and amputation of the lower leg. The femur was replaced by a modular endoprosthesis. The patient is provided with an above-knee prosthesis and is able to walk even longer distances with a cane 2 years after surgery. In our opinion it is necessary to perform a wide resection of this tumour in order to treat a patient with curative intention. Palliative radiotherapy should only be used for a non-resectable tumour or in metastatic disease. Chemotherapy is not a treatment option.     

Silver-coated megaprostheses: review of the literature

Periprosthetic infection remains one of the most serious complications following megaendoprostheses. Despite a large number of preventive measures that have been introduced in recent years, it has not been possible to further reduce the rate of periprosthetic infection. With regard to metallic modification of implants, silver in particular has been regarded as highly promising, since silver particles combine a high degree of antimicrobial activity with a low level of human toxicity. This review provides an overview of the history of the use of silver as an antimicrobial agent, its mechanism of action, and its clinical application in the field of megaendoprosthetics. The benefits of silver-coated prostheses could not be confirmed until now. However, a large number of retrospective studies suggest that the rate of periprosthetic infections could be reduced by using silver-coated megaprostheses.     

Activating mutations in the MAP-kinase pathway define non-ossifying fibroma of bone

Non-ossifying fibroma (NOF), which occasionally results in pathologic fracture, is considered the most common benign and self-limiting lesion of the growing skeleton. By DNA sequencing we have identified hotspot KRAS, FGFR1 and NF1 mutations in 48 of 59 patients (81.4%) with NOF, at allele frequencies ranging from 0.04 to 0.61. Our findings define NOF as a genetically driven neoplasm caused in most cases by activated MAP-kinase signalling. Interestingly, this driving force either diminishes over time or at least is not sufficient to prevent autonomous regression and resolution. Beyond its contribution to a better understanding of the molecular pathogenesis of NOF, this study adds another benign lesion to the spectrum of KRAS- and MAP-kinase signalling-driven tumours. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Die juvenile Knochenzyste

Background

A unicameral bone cyst (UBC) may be caused by an intraosseous venous obstruction with the accumulation of interstitial fluid. Therefore, continuous decompression of the fluid using cannulated screws would represent a causal therapeutic approach.

Materials and methods

The clinical and radiographic follow-up of 17 patients with UBCs treated by curettage and mechanical decompression using cannulated screws was evaluated retrospectively.

Results

Radiographic examination revealed the following results: complete healing of the lesion (n=2), persistent defect after healing (n=6), persistent lesion (n=6), and recurrent cyst after temporary remodeling (n=3). No pathologic fracture was subsequently observed in the group of lesions that had a persistent defect after healing. A persistent lesion occurred in the proximal femur in 75% of the cases and in the proximal humerus in 50% of the cases.

Conclusion

Continuous decompression using cannulated screws can be applied in UBCs of the proximal humerus in patients with recurrent fractures and subjective complaints. However, treatment failures are common and comparable to other therapeutic approaches. Therefore, conservative treatment must be discussed critically. Healing with residual defect must be regarded as a good treatment result, and additional operative procedures with the objective of radiographic cosmetics should not be done. Because of poor results and long-term disability related to weight bearing, treatment of UBCs with cannulated screws cannot be recommended in lesions located in the proximal femur. In these cases, immediate surgical stabilization is the appropriate procedure.     

The ganglioside antigen G(D2) is surface-expressed in Ewing sarcoma and allows for MHC-independent immune targeting

Background:

Novel treatment strategies are needed to cure disseminated Ewing sarcoma. Primitive neuroectodermal features and a mesenchymal stem cell origin are both compatible with aberrant expression of the ganglioside antigen G_D2 and led us to explore G_D2 immune targeting in this cancer.

Methods:

We investigated G_D2 expression in Ewing sarcoma by immunofluorescence staining. We then assessed the antitumour activity of T cells expressing a chimeric antigen receptor specific for G_D2 against Ewing sarcoma in vitro and in vivo.

Results:

Surface G_D2 was detected in 10 out of 10 Ewing sarcoma cell lines and 3 out of 3 primary cell cultures. Moreover, diagnostic biopsies from 12 of 14 patients had uniform G_D2 expression. T cells specifically modified to express the G_D2-specific chimeric receptor 14. G2a-28ζ efficiently interacted with Ewing sarcoma cells, resulting in antigen-specific secretion of cytokines. Moreover, chimeric receptor gene-modified T cells from healthy donors and from a patient exerted potent, G_D2-specific cytolytic responses to allogeneic and autologous Ewing sarcoma, including tumour cells grown as multicellular, anchorage-independent spheres. G_D2-specific T cells further had activity against Ewing sarcoma xenografts.

Conclusion:

G_D2 surface expression is a characteristic of Ewing sarcomas and provides a suitable target antigen for immunotherapeutic strategies to eradicate micrometastatic cells and prevent relapse in high-risk disease.