Differentiation of myxoid liposarcoma by magnetic resonance imaging: a histopathologic correlation.

BACKGROUND: Myxoid liposarcomas represent a heterogeneous group of soft tissue tumors in which prognosis is dependent on differentiation. PURPOSE: To identify magnetic resonance imaging (MRI) criteria to distinguish low-grade from high-grade myxoid liposarcomas. MATERIAL AND METHODS: MR images of 30 histologically proven myxoid liposarcomas were retrospectively reviewed. Tumors were evaluated according to size, localization, tumor border, and structure as well as tumor composition. These imaging criteria were correlated with histopathological findings. RESULTS: Nineteen myxoid liposarcomas were histologically classified as low-grade myxoid liposarcomas, whereas 11 were considered high-grade myxoid liposarcomas. Mean tumor volume of low-grade myxoid liposarcomas (710.1 ± 960.1 ccm) was significantly smaller as compared to high-grade myxoid liposarcomas (2737.0 ± 3423.7 ccm; P = 0.04). In addition to necrotic areas, three tumor components - fatty, myxoid, as well as contrast-enhancing non-fatty, non-myxoid - could be identified. The mean fraction of fatty tumor areas in low-grade myxoid liposarcomas was 10 ± 11% as compared to 6 ± 4% for high-grade myxoid liposarcomas (P = 0.66). Myxoid components accounted for 88 ± 16% in low-grade myxoid liposarcomas, but only for 45 ± 25% in high-grade myxoid liposarcomas (P < 0.0001). The non-fatty, non-myxoid tumor fraction was significantly higher in high-grade myxoid liposarcomas (50 ± 25%) as compared to low-grade myxoid liposarcomas (2 ± 9%; P < 0.0001). A proportion of > 5% of this tumor fraction was found to be a precise unique predictor for high-grade myxoid liposarcomas with a sensitivity of 100% and a specificity of 95%. CONCLUSION: Tumor components with contrast-enhancing non-fatty, non-myxoid imaging features were predominantly found in high-grade myxoid liposarcomas, which may histologically resemble round cell clusters.

[Pedunculated osteoma of the frontal sinus]. / Gestieltes Osteom der Stirnhöhle.

Osteoma, the most frequent tumor of the paranasal sinuses (PNS), is often asymptomatic. Men are more commonly affected than women. A 52-year-old patient complained of increasing incidence of headaches following the resolution of frontal sinusitis. Computer tomography demonstrated a pedunculated osteoma of the frontal sinus. Histomorphologically, PNS osteomas usually show cortical bone differentiation with sparse medullary space and a lamellar configuration. At 6 months following surgical resection, the patient was still symptom-free.

[Secondary high-malignant transformation of a low-malignant epithelial-myoepithelial carcinoma]. / Sekundäre hochmaligne Transformation eines niedrigmalignen epithelial-myoepithelialen Karzinoms.

The rare entity of epithelial-myoepithelial carcinoma (EMC) belongs to a group of tumors with a biphasic ductular growth pattern, mostly with a dominating myoepithelial component and low-grade malignancy. We report on the rare constellation of a primary low-malignant EMC with high malignant transformation (so-called dedifferentiation) into a highly malignant myoepithelial carcinoma. In the eight published cases so far, the high-malignant component was reported to be either adenocarcinoma or undifferentiated carcinoma or was otherwise not specified. To the best of our knowledge, this is the first case report of a high-grade myoepithelial carcinoma transforming from a low-grade EMC. We discuss interesting parallels to the pathogenesis of secondary transformation of carcinoma ex pleomorphic adenoma.

Perilesional changes of focal osteochondral defects in an ovine model and their relevance to human osteochondral injuries.

Perilesional changes of chronic focal osteochondral defects were assessed in the knees of 23 sheep. An osteochondral defect was created in the main load-bearing region of the medial condyle of the knees in a controlled, standardised manner. The perilesional cartilage was evaluated macroscopically and biopsies were taken at the time of production of the defect (T0), during a second operation one month later (T1), and after killing animals at three (T3; n = 8), four (T4; n = 8), and seven (T7; n = 8) months. All the samples were histologically assessed by the International Cartilage Repair Society grading system and Mankin histological scores. Biopsies were taken from human patients (n = 10) with chronic articular cartilage lesions and compared with the ovine specimens. The ovine perilesional cartilage presented with macroscopic and histological signs of degeneration. At T1 the International Cartilage Repair Society 'Subchondral Bone' score decreased from a mean of 3.0 (SD 0) to a mean of 1.9 (SD 0.3) and the 'Matrix' score from a mean of 3.0 (SD 0) to a mean of 2.5 (SD 0.5). This progressed further at T3, with the International Cartilage Repair Society 'Surface' grading, the 'Matrix' grading, 'Cell Distribution' and 'Cell Viability' grading further decreasing and the Mankin score rising from a mean of 1.3 (SD 1.4) to a mean of 5.1 (SD 1.6). Human biopsies achieved Mankin grading of a mean of 4.2 (SD 1.6) and were comparable with the ovine histology at T1 and T3. The perilesional cartilage in the animal model became chronic at one month and its histological appearance may be considered comparable with that seen in human osteochondral defects after trauma.

Bendamustine--a new approach to the treatment of advanced hepatocellular carcinoma?

AIMS: Therapeutic options for advanced hepatocellular carcinoma (HCC) are limited. Bendamustine, a bifunctional cytostatic agent with mainly alkylating effect may be an alternative. METHODS: Five HCC cell lines were incubated in vitro with five different concentrations of bendamustine. In addition, cell lines Huh-7 and HepG2 were tested in a chimeric mouse model. RESULTS: In vitro treatment with bendamustine resulted in an IC( 50 )<6 microg/mL in two, <12 microg/mL in one, and 12-23 microg/mL in two cell lines. In vivo, bendamustine reduced significantly tumor volume in chimeric mice. CONCLUSION: Bendamustine demonstrated significant tumor growth inhibition both in vitro and in vivo at concentrations that can be reached in the plasma. The potential role of bendamustine therapy for HCC and its tolerability in impaired liver function is currently subject of a phase II study.