[Mazabraud and McCune-Albright syndromes in association : A case of two very rare orthopaedic tumour entities]

We report on a 47-year-old woman with unilateral fibrous dysplasia and three intramuscular masses. Medical imaging revealed possible intramuscular myxomas, so that the suspected diagnosis was Mazabraud syndrome. After biopsy, the suspected diagnosis was verified by histology and molecular pathology. Due to endocrine abnormalities in the patient's medical history, McCune-Albright syndrome has was also verified.

[Morphological spectrum of USP6 rearranged lesions]

USP6, also known as Tre-2 and TRE17, is an ubiquitase-specific proteinase that was identified more than two decades ago as a potential oncogene when it exhibited transforming properties upon overexpression in NIH 3T3 cells. Until recently, however, little was known about the function and the oncogenetic activation of USP6. The identification of rearrangements of the USP6 gene in aneurysmal bone cyst and in nodular fasciitis has not only led to a better understanding of the pathogenesis of these entities, but is also a useful tool in their diagnosis and differential diagnostic delineation from morphological mimics. In this review, the clinical, pathomorphological, and molecular genetic aspects of aneurysmal bone cyst and of nodular fasciitis, as well as from related lesions, are presented and discussed.

Incidental finding of a giant intracardiac angioma infiltrating both ventricles in a 35-year-old woman: a case report

Background

Primary cardiac tumors are rare and often asymptomatic or present with unspecific symptoms. Benign cardiac tumors of vascular origin are especially rare, with only few existing data in the literature.

Case presentation

A 35-year-old Caucasian female patient presented to our department with an asymptomatic giant intracardiac angioma infiltrating both ventricles. Evaluation of this tumor involved electrocardiography, echocardiography, cardiac magnetic resonance imaging, coronary angiography, an open myocardial biopsy, and histological examination of the resected specimen. Because our patient was asymptomatic, she was managed conservatively with regular follow-up. We discuss the treatment options available in comparison with similar cases.

Conclusion

Diagnosis and therapy of benign cardiac tumors, especially of asymptomatic lesions, can be a challenge. There is no evidence available to help in the management of such patients. An extensive evaluation is needed with different imaging modalities, and case-specific decisions should be made that involve experts in cardiology, cardio-oncology, and heart surgery.

Electronic supplementary material

The online version of this article (doi:10.1186/s13256-016-0860-4) contains supplementary material, which is available to authorized users.

SS18-SSX fusion protein-induced Wnt/β-catenin signaling is a therapeutic target in synovial sarcoma

Synovial sarcoma is a high-grade soft tissue malignancy characterized by a specific reciprocal translocation t(X;18), which leads to the fusion of the SS18 (SYT) gene to one of three SSX genes (SSX1, SSX2 or SSX4). The resulting chimeric SS18-SSX protein is suggested to act as an oncogenic transcriptional regulator. Despite multimodal therapeutic approaches, metastatic disease is often lethal and the development of novel targeted therapeutic strategies is required. Several expression-profiling studies identified distinct gene expression signatures, implying a consistent role of Wnt/β-catenin signaling in synovial sarcoma tumorigenesis. Here we investigate the functional and therapeutic relevance of Wnt/β-catenin pathway activation in vitro and in vivo. Immunohistochemical analyses of nuclear β-catenin and Wnt downstream targets revealed activation of canonical Wnt signaling in a significant subset of 30 primary synovial sarcoma specimens. Functional aspects of Wnt signaling including dependence of Tcf/β-catenin complex activity on the SS18-SSX fusion proteins were analyzed. Efficient SS18-SSX-dependent activation of the Tcf/β-catenin transcriptional complex was confirmed by TOPflash reporter luciferase assays and immunoblotting. In five human synovial sarcoma cell lines, inhibition of the Tcf/β-catenin protein-protein interaction significantly blocked the canonical Wnt/β-catenin signaling cascade, accompanied by the effective downregulation of Wnt targets (AXIN2, CDC25A, c-MYC, DKK1, CyclinD1 and Survivin) and the specific suppression of cell viability associated with the induction of apoptosis. In SYO-1 synovial sarcoma xenografts, administration of small molecule Tcf/β-catenin complex inhibitors significantly reduced tumor growth, associated with diminished AXIN2 protein levels. In summary, SS18-SSX-induced Wnt/β-catenin signaling appears to be of crucial biological importance in synovial sarcoma tumorigenesis and progression, representing a potential molecular target for the development of novel therapeutic strategies.

Two malignant tumours in the anterior mediastinum positive for CD5

To our knowledge, the simultaneous involvement of the anterior mediastinum by a thymic carcinoma and a B-cell chronic lymphocytic leukaemia has not been reported previously. The authors describe the case of a 62-year-old man, suffering from severe bronchitis. Chest x-ray and CT scan showed a mediastinal tumour, resected short-time after diagnosis. First, standard based histological examination revealed a thymic carcinoma admixed by a dense lymphatic infiltrate. Additional immunohistochemical staining for CD5-labelled epithelial thymic carcinoma cells as well as neoplastic B cells and led in combination with blood tests to confirm the diagnosis of the composite occurrence of a thymic carcinoma and a B-cell chronic lymphocytic leukaemia.

Bilateral surgical resection in pulmonary epitheloid hemangioendothelioma

Epitheloid hemangioendothelioma is a vascular tumour with an epitheloid appearance, originating from endothelial cells. Although it is a slow growing tumour, extensive pulmonary involvement, intrathoracic spread, and systemic spread have been documented. We present a case of epitheloid hemangioendothelioma of the lung in a patient with an initial diagnosis made by transthoracic biopsy. The prognosis is unpredictable, with life expectancy ranging from 1 to 20 years. There is no single effective treatment, though spontaneous regression and response to chemotherapy and interferon are reported. Our patient underwent pulmonary lobectomy of the right lower lobe and pulmonary wedge resection of the nodule located in the left lower lobe.

Detection of the ASPSCR1?TFE3 gene fusion in paraffin-embedded alveolar soft part sarcomas

AIMS

Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumour with unique morphology and a recurrent, non-reciprocal translocation der(17)t(X;17)(p11.2;q25) leading to the fusion of ASPSCR1 (also known as ASPL) to the transcription factor TFE3. Although diagnosis is straightforward in classical cases, tumours with atypical morphological features may be difficult to classify solely on the basis of conventional histopathology. The aim of this study was to analyse the chromosomal breakpoints in paraffin-embedded tissue.

METHODS AND RESULTS

Three male and two female ASPS patients including one case with uncommon histology were investigated by fluorescence in situ hybridization with split- and fusion-probes. The presence of the resulting ASPSCR1-TFE3 fusion transcripts was assessed by reverse transcriptase-polymerase chain reaction. Hybridization results showed a t(X;17)(p11.2;q25) in all tumours with a duplication of the telomeric part of chromosome Xp. In addition to wild-type TFE3, ASPSCR1-TFE3 fusion transcripts (three type 1 and two type 2 transcripts) were detected in all cases.

CONCLUSIONS

Molecular confirmation of ASPSCR1-TFE3 gene fusion is applicable to routinely processed archival and diagnostic tumour samples and aids in the differential diagnosis of ASPS.

Clinical significance of cyclooxygenase-2 (COX-2) in multiple myeloma

Several biological and clinical considerations suggest the involvement of cyclooxygenase-2 (COX-2), the key enzyme of prostaglandin (PG) synthesis, in the pathogenesis and progression of haematological malignancies. Despite the wealth of data concerning COX-2 expression, only limited information is available on multiple myeloma (MM). Using standard immunohistochemistry we therefore evaluated COX-2 protein expression in samples from 57 patients with a primary diagnosis of MM. Time to progression and a variety of clinicopathological features were evaluated by the Kaplan-Meier method and the Cox regression model. In addition, COX-2 expression was evaluated by staining bone marrow from healthy donors and 11 patients with MGUS. Overall, 31 MM samples (54%) expressed COX-2. Positivity for COX-2 was unrelated to stage or clinical or molecular features of the disease. However, patients with COX-2 positive tumours experienced a significantly shorter time to progression (17 vs 30 months, p = 0.037). In summary, COX-2 is frequently expressed in MM and correlates with shorter progression-free survival.

Primäre Sarkome und Sarkommetastasen in der Leber

The considerable progress made in radiology, in surgical management with curative intent, and in the identification of molecularly targeted small molecules, such as the tyrosine kinase inhibitor imatinib mesylate, in the treatment of gastrointestinal stromal tumors has greatly influenced the treatment of sarcoma manifestations within the liver. This requires not only the unequivocal pathomorphological differentiation of sarcomas from other tumor entities, e. g. spindle cell dedifferentiated/pleomorphic carcinomas, aggressive non-Hodgkin lymphomas or amelanotic malignant melanomas, but also an accurate subtyping of this complex group of tumors. Additionally to macroscopic and histological findings, the recognition of characteristic immunophenotypic constellations and, at least in some types of sarcoma, the identification of molecular signatures, have greatly expanded the diagnostic tools in pathology.

Clinical significance of cyclooxygenase-2 (COX-2) in multiple myeloma

Several biological and clinical considerations suggest the involvement of cyclooxygenase-2 (COX-2), the key enzyme of prostaglandin (PG) synthesis, in the pathogenesis and progression of haematological malignancies. Despite the wealth of data concerning COX-2 expression, only limited information is available on multiple myeloma (MM). Using standard immunohistochemistry we therefore evaluated COX-2 protein expression in samples from 57 patients with a primary diagnosis of MM. Time to progression and a variety of clinicopathological features were evaluated by the Kaplan-Meier method and the Cox regression model. In addition, COX-2 expression was evaluated by staining bone marrow from healthy donors and 11 patients with MGUS. Overall, 31 MM samples (54%) expressed COX-2. Positivity for COX-2 was unrelated to stage or clinical or molecular features of the disease. However, patients with COX-2 positive tumours experienced a significantly shorter time to progression (17 vs 30 months, p = 0.037). In summary, COX-2 is frequently expressed in MM and correlates with shorter progression-free survival.

The location of KIT and PDGFRA gene mutations in gastrointestinal stromal tumours is site and phenotype associated

AIMS

To assess the relation between KIT and PDGFRA mutations and the site of origin, histological phenotype, and pathomorphologically determined risk assessment in gastrointestinal stromal tumours (GISTs).

METHODS

A series of 83 clinicopathologically characterised GISTs from 79 patients was analysed for KIT and PDGFRA mutations by polymerase chain reaction amplification, single strand conformation polymorphism analysis, and direct DNA sequencing.

RESULTS

KIT or PDGFRA mutations were found in 57 and 11 GISTs, respectively. Most KIT mutations involved exon 11 (46 cases), followed by exon 9 (10 cases). The PDGFRA mutations mostly affected exon 18 (eight cases), followed by exon 12 (three cases). There was a significant association between KIT exon 9 mutations and an intestinal origin of GISTs, and between PDGFRA mutations and gastric origin of the tumours. In addition, the presence of PDGFRA mutations was significantly associated with epithelioid/mixed histology, as was the absence of identified receptor tyrosine kinase mutations. Vice versa, KIT exon 11 mutations were almost exclusively found in spindle cell GISTs. Furthermore, the presence of any KIT and PDGFRA mutations and the presence of KIT mutations alone were significantly associated with high risk/malignant GISTs.

CONCLUSIONS

The location of KIT and PDGFRA mutations in GISTs is associated with the site of origin and histological phenotype. Genotyping of GISTs may be a helpful additional parameter in determining the biological profile of these tumours.

Impaired CD95 expression predisposes for recurrence in curatively resected colon carcinoma: clinical evidence for immunoselection and CD95L mediated control of minimal residual disease

BACKGROUND

Loss of CD95 expression in tumour cells occurs frequently in colon carcinoma and may be associated with disease progression. On the other hand, neo-expression of CD95L in tumour cells may contribute to immune evasion.

AIMS

We aimed at further exploring the functional role and prognostic significance of the CD95/CD95L death inducing system in colon carcinomas.

PATIENTS AND METHODS

CD95 and CD95L expression was examined by immunohistochemistry in 128 R0 resected UICC (International Union against Cancer) stage II/III colon carcinomas and correlated with disease free survival.

RESULTS

CD95 expression in tumour cells was observed in only 30 carcinomas (23.4%) whereas the others had at least a minor subpopulation of CD95 negative cells. Loss of CD95 in tumour cells was related to adverse prognosis in uni- and multivariate analysis (p = 0.046 and p = 0.036, respectively). Tumour infiltrating lymphocytes (TIL) were the major source of CD95L in colon carcinomas. CD95L+TIL were present in 83% of cases whereas CD95L was found in tumour cells in only 12% of cases. Moreover, a high rate of CD95L+TIL correlated with prolonged disease free survival in patients with UICC stage II (p = 0.05) but not in those with stage III.

CONCLUSIONS

Loss of CD95 in tumour cells may be an independent prognostic factor in colon carcinomas. The CD95L counterattack is not a relevant feature in colon carcinoma but CD95L+TIL may contribute to tumour control in the early stages of the disease, exerting a concurrent selection pressure in the direction of CD95 abrogation/resistance.

Onkogene Osteomalazie bei einer 49-jährigen Patientin

HISTORY AND CLINICAL FINDINGS

A 49-year-old woman presented with increased bone and muscle pain of the left thigh and also of the left ribs since 1 1/2 year. 2 osteolytic regions on the left proximal femur were punctured but no tumour-like changes were found.

INVESTIGATIONS

Laboratory tests showed a severe hypophosphataemia (0.33 mmol/l), increased serum alkaline phosphatase activity and moderate elevated parathyroid hormone. Renal loss of phosphate was measured under phosphate substitution. The bone mineral density (DXA) was decreased. With octreotid scintigraphy a somatostatine receptor positive tumour was detected on the right proximal thigh and magnetic resonance scanning confirmed localization of the tumour.

TREATMENT AND COURSE

Treatment with oral phosphate and calcitriol improved the complaints presently. After total removal of a mesenchymal tumour, normalization of serum phosphate occurred and the patient did not require any medicine and did not have complaints anymore.

CONCLUSION

In a case of uncertain hypophosphataemic osteomalacia in adults it is essential to search for a tumour after exclusion of the rare differential diagnoses to enable a causal treatment of a potentially oncogenic osteomalacia.

High-dose chemotherapy with autologous peripheral blood stem cell transplantation for bone and soft-tissue sarcomas

The role of high-dose chemotherapy (HDCT) with PBSCT in the treatment of bone and soft-tissue sarcomas is not established. In total, 27 patients (15 female, median age at TPL 30.6 years (range: 13-59)) were analyzed (Ewing sarcoma family n=8, osteosarcoma n=6, MPNST (malignant peripheral nerve sheath tumor) n=4, synovial sarcoma n=3, liposarcoma n=2, leiomyosarcoma n=2, rhabdomyosarcoma n=1, meningosarcoma n=1). Following chemotherapy and surgery complete remission (CR) (n=9), partial remission (PR) (n=10), stable disease (SD) (n=2) and progressive disease (PD) (n=6) were reached prior HDCT. Different HDCT conditioning regimens were used. One patient died due to cardiac arrest after HDCT. Except hematologic side effects, no WHO grade III-IV complications were observed. Four patients died within 6 months due to PD, disease recurred in another seven patients and led to death, 15 patients are alive with/without disease. The median progression-free survival (PFS) is 12.0 months (range: 0-58), in nine CR patients median PFS is 25.8 months (range: 3-58). Although the role of HDCT in the treatment of sarcomas is not defined, a subgroup of patients who achieved CR before HDCT could benefit from this therapy.

[Gastrointestinal stromal tumors. A morphologic and molecular genetic independent tumor entity with new therapeutic perspectives]

Recent morphological and molecular genetic findings have greatly expanded our understanding of gastrointestinal stromal tumors (GISTs). GISTs are now defined by their overexpression of CD117 (KIT), the receptor for the stem cell factor, and can thus be discriminated from smooth muscle tumors. Cytogenetically, GISTs are characterized even in early lesions by frequent entire or partial loss of the chromosomes 14 and 22 and terminal deletions of the chromosomal arm 1p. During tumor progression further chromosomal imbalances accumulate. Following the first report on activating KIT mutations in GISTs, several studies have addressed the role of wild-type and mutant KIT in GISTs and demonstrated activating KIT mutations in the majority of cases. Moreover, KIT tyrosine phosphorylation is even present in KIT mutation-negative GISTs, implicating KIT activation as a central event in the pathogenesis of GISTs. Imatinib (STI571/Glivec) is a selective inhibitor of BCR/ABL, PDGFR and KIT receptor-tyrosine kinases. First therapeutic applications of imatinib in patients with progressive GISTs have yielded promising results. This review focuses on the morphological and molecular findings in GISTs which have opened up a new therapeutic perspective.

[MR imaging of gastric wall layers in vitro: correlation to thehistologic wall structure]

PURPOSE

To correlate gastric wall layers visible of MRI with the anatomical structure of the gastric wall.

METHODS

After macroscopic preparation 5 x 5 cm post-mortem tissue sections of the gastric antrum were evaluated using a 2.4 Tesla MR unit (Bruker, Ettlingen, Germany). MR imaging consisted of T2-weighted multi-spinecho sequences in longitudinal and axial directions. The specimens then were stained with hematoxylin-eosin for histological examination. After that histological correlation of the gastric wall layers visible on MRI was performed.

RESULTS

In all specimens four gastric wall layers could be clearly identified on MRI. The direct comparison of those layers to the histological findings showed the following correlation: 1) intermediate signal = mucosa, 2) hypointense signal = lamina muscularis mucosae, 3) hyperintense signal = submucosa, 4) intermediate signal = muscularis propria.

CONCLUSIONS

Gastric wall layers visible on MRI were successfully correlated to the anatomic layers of the gastric wall. This allows us for the first time to classify invasion of gastric carcinoma using high spatial-resolution MR imaging. However, the subserosa and serosa are excluded from this conclusion, because so far a reliable statement concerning the value of MRI to depict these very variable layers is not possible.

Assessment of clonality of rosetting T lymphocytes in Hodgkin's disease by single-cell polymerase chain reaction: detection of clonality in a polyclonal background in a case of lymphocyte predominance Hodgkin's disease

Rosetting of CD4+ T cells around the neoplastic Hodgkin and Reed-Sternberg (H&RS) cells is a characteristic feature of Hodgkin's disease (HD). To answer the question whether this phenomenon is solely due to chemokine-mediated attraction of T cells or whether the rosetting T cells in addition recognize antigens presented by the H&RS cells, we examined the T cells adherent to H&RS cells. Cells from five cases of HD [four classic HD and one lymphocyte-predominant (LP) HD] were examined by single-cell analysis for the T-cell receptor (TCR) gamma gene. Between 5 and 17 rosettes containing one to ten rosetting lymphocytes and the corresponding H&RS cells were amplified in separate plastic tubes. Of the resulting 119 TCRgamma polymerase chain reaction (PCR) products, 87 were sequenced. While no evidence of a clonal expansion was obtained in the lymph nodes from four of five patients with classic HD, clonal TCRgamma sequences were found in the lymph node from the patient within LPHD in two independent experiments analyzing seven and ten different rosetting complexes, respectively. Of 13 products, 11 showed identical Vgamma9 sequences. Unrelated products were found in all other TCRgamma family subgroups in this case. Single H&RS cells picked as controls were negative for TCRgamma rearrangements. Our results demonstrate that clonal proliferations on a polyclonal background can occur among the T cells forming rosettes with Hodgkin cells and lend support to the view that Hodgkin cells may also function as cells presenting antigens to the adhering T cells.

Assessment of soft tissue lesions suspicious for liposarcoma by F18-deoxyglucose (FDG) positron emission tomography (PET)

BACKGROUND

F18-deoxyglucose (FDG) positron emission tomography (PET) is a promising imaging technique. The aim of this study was to investigate the use of FDG PET in patients with suspected liposarcomas (LS).

PATIENTS AND METHODS

Forty-two masses were studied. The FDG uptake was estimated in tumor (T) and normal tissue (NT). The data were analyzed with respect to pathological findings.

RESULTS

Pathology revealed 11 primary LS, 14 locally recurrent LS, 5 other sarcomas, 1 inflammation, 1 lymphoma and 10 benign lesions. FDG uptake (T-to-NT ratio) in 25 LS corresponded with the histological subtype. Pleomorphic, mixed and myxoid LS showed an increased T-to-NT ratio and were thus visualized. Four out of six well-differentiated LS presented a low FDG uptake. Like subtype, the tumor grade also corresponded to FDG uptake. The T-to-NT ratio of higher grade LS, contrary to low grade LS, was uniformly increased. Primary LS were distinguishable from benign tumors, while other sarcomas, inflammation and lymphoma were not. Recurrence was detected with a sensitivity of 86% and a specificity of 100%. False-negative diagnoses occurred only in well-differentiated recurrences.

CONCLUSION

FDG uptake in LS correlates with the histological subtype and tumor grade. The diagnostic value of FDG PET in LS, therefore, is influenced by histomorphological parameters. Our data suggest that pleomorphic, mixed and higher-grade LS recurrences are preferentially amenable to FDG PET imaging.

Dynamic PET 18F-FDG studies in patients with primary and recurrent soft-tissue sarcomas: impact on diagnosis and correlation with grading

The purpose of this study was to evaluate (18)F-FDG PET studies of primary and recurrent sarcomas for diagnosis and correlation with grading.

METHODS

The evaluation included 56 patients, 43 with histologically proven malignancies and 13 with benign lesions. Seventeen patients were referred with suspicion on a primary tumor, and the remaining 39 were referred with suspicion on a recurrent tumor. The FDG studies were accomplished as a dynamic series for 60 min. The evaluation of the FDG kinetics was performed using the following parameters: standardized uptake value (SUV), global influx, computation of the transport constants K1-k4 with consideration of the distribution volume (VB) according to a two-tissue-compartment model, and fractal dimension based on the box-counting procedure (parameter for the inhomogeneity of the tumors).

RESULTS

Visual evaluation revealed a sensitivity of 76.2%, a specificity of 42.9%, and an accuracy of 67.9%. The vascular fraction VB and the SUV were higher in malignant tumors compared with benign lesions (t test, P < 0.05). Although the FDG SUV helped to distinguish benign and malignant tumors, there was some overlap, which limited the diagnostic accuracy. The SUV and fractal dimension accounted for significant differences in six of the nine diagnostic pairs. Whereas grade (G) II and G III tumors were differentiated from lipomas on the basis of the fractal dimension and some other kinetic parameters, no differences were found between G I tumors and lipomas. On the basis of the discriminant analysis, the differentiation of soft-tissue tumors was best for the use of six parameters of the FDG kinetics (SUV, VB, K1, k3, influx, and fractal dimension). Eighty-four percent of G III tumors, 37.5% of G II tumors, 80% of G I tumors, 50% of lipomas, and 14.3% of scars could be classified correctly, whereas inflammatory lesions were misclassified.

CONCLUSION

FDG PET should be used preferentially for monitoring patients with G III sarcomas. Visual analysis provides a low specificity. In contrast, the evaluation of the full FDG kinetics provides superior information, particularly for the discrimination of G I and G III tumors (positive predictive value, >80%).

Detection of chromosomal imbalances in leiomyosarcoma by comparative genomic hybridization and interphase cytogenetics

Leiomyosarcomas comprise a group of malignant soft-tissue tumors with smooth-muscle differentiation. In this study, 14 cases of leiomyosarcoma were screened for changes in relative chromosome copy number by comparative genomic hybridization. A high number of imbalances (mean, 16.3; range, 6-26) was detected, with chromosomal gains occurring about twice as much as losses. The most frequent gains were found in 5p15, 8q24, 15q25-->q26, 17p, and Xp (43% to 50%), whereas the most frequent losses were found in 10q and 13q (50% and 78%, respectively). Twenty high-level amplifications affecting 15 different chromosomal subregions were detected in nine different tumors. In three leiomyosarcomas, sequences on chromosome arm 17p were found to be highly amplified, with a minimal overlapping region on subbands 17p12-->p11. We further discovered that the Smith-Magenis syndrome critical region on 17p11.2 is included in the 17p amplicons of two leiomyosarcoma cases. Using probes flanking this genetically unstable region, a mean of 14 and 22 signals per nucleus, respectively, was detected in both leiomyosarcomas by fluorescence in situ hybridization. In conclusion, this analysis identifies a number of characteristic chromosomal imbalances in leiomyosarcomas and provides evidence for the localization of potential oncogenes and tumor suppressor genes active in leiomyosarcoma genomes.

LiSa-2, a novel human liposarcoma cell line with a high capacity for terminal adipose differentiation

LiSa-2 is a stable cell line derived from a poorly differentiated, pleomorphic liposarcoma. In serum-containing medium, LiSa-2 cells are fibroblastoid and rapidly dividing. In a serum-free, chemically defined culture medium containing physiological concentrations of insulin, triiodothyronine and cortisol, LiSa-2 cells divide slower and, extensively storing fat, acquire adipocyte morphology. In contrast to fibroblastoid LiSa-2 cells, these adipocyte-like LiSa-2 cells highly express transcripts for peroxisome proliferator-activated receptor-gamma, lipoprotein lipase, fatty acid synthetase, hormone-sensitive lipase, adipocyte most abundant gene transcript-1, glycerol-3-phosphate-dehydrogenase and the insulin-sensitive glucose transporter-4, all of which are specific for differentiated adipocytes. However, leptin mRNA expression was demonstrated only after preventing DNA methylation by incorporation of 5-aza-deoxycytidine into cellular DNA. Functionally, adipocyte-like LiSa-2 cells show increased insulin-dependent glucose uptake and lipid synthesis and are sensitive to lipolytic agents. This cell line may serve as an in vitro model for studying the regulation of human liposarcoma differentiation and for screening drugs for induction of differentiation-associated growth arrest in liposarcomas.

[Results of oncological reoperation in primary soft tissue sarcomas]

BACKGROUND

Soft tissue sarcomas (STS) are frequently resected incompletely or without an adequate margin. In such clinical situations an oncological re-resection (wide or compartmental resection or amputation) is recommended. Here, we evaluate the results of oncological re-resection for STS.

METHODS

Prospectively gathered data on 67 patients who underwent oncological re-resection after inadequate (intracapsular or marginal) surgery for primary soft tissue sarcomas were analyzed.

RESULTS

STS were located in the extremities (85%) and trunk (15%). Advanced UICC stages (1992, 4th edn., 2nd Rev.), IIB-IIIB predominated (66%). Twenty-five patients received intraoperative radiotherapy. Morbidity of re-resection was 28.4%. Residual tumor was detected in 64% of the specimens and clear margins were obtained in 60 patients (90%). With a median follow-up of 57 months the overall local control in patients with tumor-free resection margins was 88% (UICC IA-IIA 100%, IIB-IIIB 82%). Patients treated by adjuvant intraoperative radiotherapy for UICC stages IIB-IIIB with clear margins achieved 90% local control. The 5-year overall survival rate was 87% in patients with tumor-free resection margins.

CONCLUSIONS

These findings support the strategy of oncological re-resection after previously non-oncological surgery of STS and imply that re-resection is the prerequisite for any effective adjuvant therapy modality.

Clinical value of [18-F]] fluorodeoxyglucose positron emission tomography imaging in soft tissue sarcomas

OBJECTIVE

To evaluate positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) for clinical application in soft tissue sarcomas.

SUMMARY AND BACKGROUND DATA

FDG PET is a promising noninvasive method for the preoperative assessment of soft tissue sarcomas and may complement radiologic tomography.

METHODS

Data from 50 consecutive patients with 59 masses, either suspicious for primary or locally recurrent soft tissue sarcoma, were prospectively gathered. The semiquantitative FDG uptake (standardized uptake values [SUVs]) was calculated in tumor and normal tissue (muscle). Histopathology of surgical specimens and follow-up data were used as control criteria.

RESULTS

In primary soft tissue sarcomas, PET displayed a sensitivity of 91% and a specificity of 88%. Local recurrence was detected with a sensitivity of 88% and a specificity of 92%. All intermediate-grade and high-grade soft tissue sarcomas (primary and locally recurrent) were visualized with a precise differentiation from muscle. Fifty percent of the low-grade sarcomas showed an FDG uptake equivalent to muscle (false-negative results in one primary and three recurrent soft tissue sarcomas). Benign soft tissue tumors (e.g., lipoma, leiomyoma, ganglion) did not accumulate FDG. Inflammation resulted in an increased FDG uptake. The semiquantitative FDG uptake (SUVs) correlated with tumor grade but not with size and histologic type.

CONCLUSION

High-grade and intermediate-grade soft tissue sarcomas are amenable to PET imaging, whereas low-grade lesions may not be depicted. SUVs for FDG correlate with tumor grade in soft tissue sarcomas. Benign soft tissue tumors are differentiated from higher-grade soft tissue sarcomas. These data show that FDG-PET can complement preoperative radiologic assessment for soft tissue sarcomas and that FDG-PET is a powerful diagnostic tool for detecting high-grade and intermediate-grade local recurrence.

Adenocarcinoma of the stomach with tumor-thrombotic microangiopathy in an 11-year-old male patient

The majority of malignancies in childhood are represented by leukemias, lymphomas or other reticuloendothelial neoplasms, tumors of the central nervous system, nephroblastomas and sarcomas. Gastrointestinal tumors represent less than 5% of pediatric neoplasms and carcinomas within this subgroup have been very rarely described, especially those arising in the stomach. In this study, we report a case of an 11-year-old boy with a signet-ring carcinoma of the stomach. The patient initially presented with respiratory symptoms which were caused by massive pulmonary lymphangiosis carcinomatosa and a peculiar microangiopathy, recently addressed as pulmonary tumor thrombotic microangiopathy. To our knowledge, this constellation has not been reported so far.

Genomic imbalances including amplification of the tyrosine kinase gene JAK2 in CD30+ Hodgkin cells

Comparative genomic hybridization was applied for a comprehensive screening of frequently occurring net gains and losses of chromosomal subregions in small populations of CD30+ Hodgkin cells and their morphological variants. In 12 Hodgkin's lymphomas, recurrent gains were detected on chromosomal arms 2p, 9p, and 12q (in six, four, and five tumors, respectively) and distinct high-level amplifications were identified on chromosomal bands 4p16, 4q23-q24, and 9p23-p24. In Hodgkin cells with 9p23-p24 amplification, fluorescence in situ hybridization revealed an increased copy number of chromosomal sequences spanning the tyrosine kinase gene JAK2. Several of the imbalances described, in particular a gain in chromosomal arm 9p that includes JAK2 amplification, are similar to the genomic changes detected in primary mediastinal B-cell lymphoma.

[Deciduosis of the appendix. Differential diagnosis of acute appendicitis]

Deciduosis of the appendix is a rare cause of acute appendicitis in pregnancy. Ectopic decidual cells localized in the submesothelial stroma may represent a physiologic reaction of the pluripotent stromal cells to progestational hormonal stimulation. Less frequently, deciduosis is based on a preexisting extragenital endometriosis, visible in a localization other than strictly submesothelial, in residuals of cyclic proliferation and bleeding, and in endometrial glandular formations embedded in the decidual cells.

Cystic lymphangioma of the small-bowel mesentery: case report and a review of the literature

Cystic lymphangioma of the small-bowel mesentery is a rare manifestation of an intraabdominal tumor in elderly patients. We present a case of a small-bowel mesentery lymphangioma, causing fever and chills and present clinical and pathologic features. Furthermore, etiology and differential diagnosis of this tumor are discussed.