MYC high level gene amplification is a distinctive feature of angiosarcomas after irradiation or chronic lymphedema.

Angiosarcomas (AS) are rare vascular malignancies that arise either de novo as primary tumors or secondary to irradiation or chronic lymphedema. The cytogenetics of angiosarcomas are poorly characterized. We applied array-comparative genomic hybridization as a screening method to identify recurrent alterations in 22 cases. Recurrent genetic alterations were identified only in secondary but not in primary AS. The most frequent recurrent alterations were high level amplifications on chromosome 8q24.21 (50%), followed by 10p12.33 (33%) and 5q35.3 (11%). Fluorescence in situ hybridization analysis in 28 primary and 33 secondary angiosarcomas (31 tumors secondary to irradiation, 2 tumors secondary to chronic lymphedema) confirmed high level amplification of MYC on chromosome 8q24.21 as a recurrent genetic alteration found exclusively in 55% of AS secondary to irradiation or chronic lymphedema, but not in primary AS. Amplification of MYC did not predispose to high grade morphology or increased cell turnover. In conclusion, despite their identical morphology, secondary AS are genetically different from primary AS and are characterized by a high frequency of high level amplifications of MYC. This finding may have implications both for the diagnosis and treatment of these tumors.

Lymphangioleiomyomatosis: solitary abdominal manifestation (2009: 9b).

Lymphangioleiomyomatosis (LAM) is a rare disease that usually affects premenopausal woman and is characterized by cystic lung lesions and lymphatic disorders. We report a case of a 23-year-old woman who presented with diffuse, but increasing abdominal pain. Transabdominal ultrasound showed multiple cystic formations. Due to the patient's uncharacteristic symptoms, an exploratory laparotomy with tissue sampling was performed, and the diagnosis of LAM was confirmed by two independent pathologists. With computed tomography a broad abdominal, but no pulmonary, manifestation could be established. During sirolimus therapy the patient showed clinical benefit, but only slight progress in computed tomography.

D2-40 labeling in lymphangiomyoma/lymphangiomyomatosis of the soft tissue: further evidence of lymphangiogenic tumor histogenesis.

We examined ten cases of extrapulmonary lymphangioleiomyoma/lymphangioleiomyomatosis (LAM; all patients female; median age 46.5 years) for immunohistochemical labeling with a monoclonal antibody against podoplanin (D2-40), which is specific for lymphatic endothelial lining. We found positive staining in thin-wall branching vessels reflecting the lymphatic nature of tumor vessels in all cases tested. In contrast, perivascular (HMB-45 positive) myoid cells were not detected by D2-40. The D2-40 labeling confirms the current concept of lymphangiogenic origin of the tumor vessels in LAM. In addition, this study makes a further contribution to the immunohistochemical mapping of this antibody in vascular tumors. Finally, the use of this commercially available antibody provides an additional help in the differential diagnosis of LAM from other soft tissue tumors.

D2-40 staining in sinonasal-type hemangiopericytoma--further evidence of distinction from conventional hemangiopericytoma and solitary fibrous tumor.

D2-40 is a monoclonal antibody, which reacts with a fixative-resistant epitope of lymphatic endothelium. Sinonasal-type hemangiopericytoma (SHP) and tumors of the (conventional) hemangiopericytoma/solitary fibrous tumor family (HP/SFT) are characterized by prominent vasculature. However, data concerning D2-40 labeling of these tumors are very sparse. In the present study, we investigated D2-40 staining in tissue specimens of 17 patients with SHP (male to female ratio of 2.4:1, median age of 63 years) and compared the immunolabeling with 20 cases of HP/SFT, including three SFT cases from nasal mucosa. D2-40 was detected in vascular channels of all SHP patients examined. By contrast, all cases of HP/SFT did not reveal any vascular channel being positive for D2-40, neither in the nasal cases nor in the remaining patients. This study presented for the first time data on D2-40 labeling in a series of SHP, HP/SFT, and supports the distinction of SHP from HP/SFT.

Rhabdomyoma of the head and neck: morphology and differential diagnosis.

Rhabdomyomas of the head and neck are exceptionally rare benign mesenchymal tumors. Although histology is very characteristic, several differential diagnoses have to be considered. We investigated five patients with extracardiac rhabdomyoma of the head and neck (median age 65.9 years), four of them presenting with adult rhabdomyoma (AR) and one with fetal rhabdomyoma (FR). We analyzed the histological findings, with special regard to separation from hibernoma (two patients) and granular cell tumor (GCT; six patients, median age 31 years). Both FR and AR showed polygonal eosinophilic cells with peripherally or centrally localized nuclei and cross striations, while in hibernoma, multivacuolated cells with centrally localized nuclei were detected. In GCT, polygonal eosinophilic cells with granular periodic-acid-Schiff-positive cytoplasm were found; in one case, atypical GCT with increased pleomorphism and mitotic rate was observed. Pseudoepitheliomatous hyperplasia occurred both in FR and GCT. Immunohistochemically, rhabdomyomas were strongly positive for myogenic markers (desmin, actin, and myoglobin) but negative for S-100, while hibernoma and GCT strongly expressed S-100. Concerning the differential diagnosis of rhabdomyoma, GCT has to be especially considered since this tumor can undergo malignant transformation.

Unusual sarcomatoid neoplasm of the lung suggesting a myofibrosarcoma.

Myofibrosarcoma is a rare neoplasm that occurs mainly in the head and neck region and extremities of middle-aged patients. It often appears as a low-grade sarcoma and rarely metastasizes. We report the case of a 47-year-old male patient with a malignant mesenchymal pulmonary tumor affecting almost the entire lower left lobe. Clinically suggestive for a lung carcinoma, the tumor showed typical features of a myofibrosarcoma. A major spindle cell component was observed being positive for smooth-muscle actin, calponin, and vimentin, while stainings for desmin, h-caldesmon, alkaline phosphatase (ALK), and extensively studied cytokeratins were negative. Striking was a strong infiltrate with neutrophilic and eosinophilic granulocytes. DNA cytometry revealed aneuploidy with a peak in the near triploid range. Comparative genomic hybridization demonstrated multiple DNA gains and losses correlating with an aggressive clinical course. Shortly after resection of the primary tumor, the patient showed multiple distant metastases in the contralateral lung, the mediastinal lymph nodes, the left adrenal gland, and the pectoral and deltoid muscle, which responded well to chemotherapy. The case report will discuss the evidence for the final diagnosis of a primary pulmonary myofibrosarcoma and the differential diagnosis of sarcomatoid tumors of the lung.

Loss of CD34 and high IGF2 are associated with malignant transformation in solitary fibrous tumors.

The aim of this study was to characterize the subgroups of solitary fibrous tumor (SFT) and to investigate the expression of different biomarkers including CD34 and IGF2 in malignant transformation. Two hundred and ninety-four (294) SFTs from a single German consultation center of soft tissue tumors were categorized into the new proposal of SFT designation. We found the fibrous variant in 223 (75.9%), the cellular variant in 65 (22.1%), the fat forming variant in 4 (1.4%), and the giant cell-rich variant in 2 (0.6%) cases. Anatomical location, size, mitotic index, necrosis, cellularity, collagenous ropes, and growth pattern of the vessels were recorded. Criteria of malignancy were found in 68 (23%) tumors. Expression of IGF2, IGF1R, CD34, BCL2, CD99, SMA, S100, PanCK, and Ki67 was analyzed immunohistochemically. Low expression of CD34 and high expression of IGF2 were significantly associated with malignant transformation and the metastatic rate. Moreover the presence of necrosis showed the most significant p-value (p<0.004). Of all SFTs, the fibrous variant is the most common, followed by the cellular variant. The fat-forming and giant cell-rich variants are very rare. Low expression of CD34 and high expression of IGF2 are significantly associated with malignant transformation, and might be an interesting target of individualized therapy.

High IGF2 and FGFR3 are associated with tumour progression in undifferentiated pleomorphic sarcomas, but EGFR and FGFR3 mutations are a rare event.

AIM: Pleomorphic undifferentiated sarcomas (formerly known as malignant fibrous histiocytomas) are recognised by the actual WHO classification as an undifferentiated, unclassifiable category of pleomorphic sarcomas which show no definable line of differentiation and are still a diagnosis of exclusion. Therefore, diagnostic, prognostic and therapeutic options of these tumours are urgently needed. METHODS: Three hundred and twenty-seven spindle cell tumours of a German consultation and reference centre of soft tissue tumours consisting of 200 undifferentiated pleomorphic sarcomas (UPS), 45 low-grade sarcomas (10 low-grade fibromyxoid sarcomas, 32 low-grade myofibroblastic sarcomas and three myxoinflammatory fibroblastic sarcomas) and 82 tumours of the fasciitis family were revisited. The specimens were analysed immunohistochemically with distinct markers including tyrosine kinases and expression correlated with clinicopathological parameters. Additionally, mutational analysis was performed on specimens with high expression of EGFR and FGFR3. RESULTS: At the protein level high IGF2 expression was observed in 86 %, FGFR3 (69 %), PDGFRA (62 %), PDGFRB (39 %), FGFR1 (8 %), EGFR (5 %), KDR/VEGFR2 (3 %), ALK (0 %) and high Ki67 (63 %) in UPS. High expressions of IGF2 and FGFR3 are significantly correlated with a higher grading (p = 0.023 and p = 0.016, respectively) and a high Ki67 index (p = 0.017 and p = 0.001, respectively). No mutations were found in the hot spots of tumour specimens with a high expression of EGFR gene (exons 18-21) and FGFR3 gene (exons 7, 10 and 15). CONCLUSIONS: High expressions of IGF2 and FGFR3 are significantly associated with tumour progression, grading and Ki67 and might classify a subgroup of undifferentiated pleomorphic sarcoma. These markers might guide targeted therapies in these neoplasms.

Mammalian target of rapamycin pathway activity in alveolar soft part sarcoma.

Alveolar soft part sarcoma (ASPS) is a distinct type of soft tissue sarcoma holding a specific ASPL-TFE3 fusion transcript. Curative therapy is based on surgical removal, whereas lately, antiangiogenic targeted therapy regimens have proven effective. In ASPS, analysis of small series additionally display mTOR (mammalian target of rapamycin) pathway activity, thus making mTOR a possible additive target in ASPS, because it is in other tumor entities. Therefore, we systematically evaluated mTOR pathway activity in a large series of ASPS in comparison with soft tissue sarcomas of other differentiation (non-ASPS). Upstream and downstream factors of mTOR signaling and ancillary targets were analyzed in 103 cases (22 ASPS, 81 non-ASPS) by immunohistochemistry mostly using phospho-specific antibodies. TFE3 (transcription factor for immunoglobulin heavy-chain enhancer 3) translocation status was determined by FISH and RT-PCR. All ASPS were positive in TFE3 break-apart FISH and exhibited specific fusion products when RNA was available (type 1: 9x, type 2: 11x), whereas TFE3-immunoreactive non-ASPS did not. In ASPS, TFE3-, cMET-, pAKT T308- (all P < .0001), pp70S6K- (P = .002), and p4EBP1 (P = .087) expression levels were elevated, whereas pAKT S473 was decreased (P < .0001). In addition, ASPS exhibited higher TFE3-, cMET-, pAKT T308-, and pp70S6K- expression levels compared with TFE3-immunopositive non-ASPS sarcomas (all P < .001). We demonstrate elevated mTOR complex 1 (mTORC1) activity in ASPS independent of mTOR complex 2 (mTORC2) activation. mTORC1 activity seems to be related to the existence of ASPL-TFE3 fusion transcripts because TFE3-immunoreactive non-ASPS without ASPL-TFE3 fusion transcripts exhibit significantly lower mTORC1 activation status. Small molecule-based targeting of mTOR might therefore represent a potential mechanism in ASPS alone or in combination with contemporary upstream approaches.

Thoracic neoplasms at the Jena reference center for soft tissue tumors.

INTRODUCTION: The Jena Soft Tissue Tumor Reference Center is the major German pathology institute for consultation of malignant mesenchymal tumors. Here, we present the clinicopathological data on thoracic soft tissue tumors of a two-year period. METHODS: The tumors were analyzed according to their localization, type (soft tissue tumor, other tumor type, non-neoplastic lesion) and biological behavior. The frequency of the defined soft tissue tumor entities were considered after categorizing the cases according to the WHO Classification of Tumors. Gender and age were also assessed. RESULTS: In total, 1,071 cases of thoracic tumors were recorded within the 2 years. The majority were non-epithelial lesions (75.3%, n = 806/1,071), of which 68.1% (n = 549/806) were malignant or intermediate malignant. 107 non-epithelial lesions involved the lung and 37 the pleura. By far the most common lung and pleural tumors were undifferentiated sarcomas. In the lung, other frequent entities were solitary fibrous tumors, synovial sarcomas and leiomyosarcomas. We also recorded 13 non-epithelial tumors of the heart and 66 tumors of the breast with angiosarcomas being the most frequent subtype. There was a female predominance for vascular neoplasms, while men prevailed for adipocytic tumors. CONCLUSIONS: Our study provides information about the frequency, distribution, age and gender of patients with thoracic soft tissue tumors including several rare entities. Thus, it may help in the differential diagnosis of these neoplasms. In addition, we present a model highlighting the potential progression of lung carcinoma to undifferentiated sarcoma via the process of epithelial-mesenchymal transition.

Identification of biomarkers to distinguish clear cell sarcoma from malignant melanoma.

Clear cell sarcoma is a rare and malignant soft tissue tumor that shows phenotypic and immunohistochemical overlap with cutaneous malignant melanoma; identification of biomarkers that differentiate clear cell sarcoma from malignant melanoma is therefore needed. In this study, we performed mutation analysis of BRAF and NRAS, investigated the EWSR1 gene rearrangement and evaluated the protein expression of insulin-like growth factor 2 and insulin-like growth factor 1R in 31 cases of malignant melanoma and 16 cases of clear cell sarcoma. By direct sequencing and high-resolution melting analysis, we identified BRAF and NRAS mutations in 51.6% and 12.9% of malignant melanoma cases, respectively, while none of clear cell sarcoma harbored BRAF or NRAS mutations. Fluorescence in situ hybridization showed that 78.6% of clear cell sarcoma exhibited the t(12;22)(q13;q12) translocation. The presence of type 1, 2, and 3 EWSR1/ATF1 fusion gene transcripts was confirmed by reverse transcriptase polymerase chain reaction analysis, but type 4 and EWSR1/CREB1 fusion gene transcripts were not found. No fusion transcript could be detected in any of the malignant melanoma cases. Additionally, immunohistochemistry showed that the majority of clear cell sarcoma and malignant melanoma had insulin-like growth factor 2 and insulin-like growth factor receptor 1 expression; however the expression of insulin-like growth factor 1R was significantly higher in clear cell sarcoma compared to melanoma (p = .006). Our results suggest that the combination of BRAF and NRAS mutation analysis with fusion gene detection contributes to diagnosis of malignant melanoma and clear cell sarcoma, and that insulin-like growth factor 1R might be a novel target for the treatment of these two malignancies.

An unusual case of a synovial sarcoma of the parotid gland in an elderly patient.

Synovial sarcoma is a malignant soft tissue neoplasm which mostly occurs in adolescents and young adults. The tumor is rare in the head and neck region although it has been described at virtually every anatomic site. Synovial sarcoma can mimic benign lesions clinically and histologically and is therefore sometimes difficult to diagnose. We present a case of a synovial sarcoma in the parotid gland of a 72-year old patient. Immunohistochemistry and genetic testing of the tumor were performed to confirm the diagnosis. The treatment options are discussed. The case shows that synovial sarcoma should be considered as a differential diagnosis for uncertain parotid lesions in all age groups.

Molecular cytogenetic characterization of epithelioid hemangioendothelioma.

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor whose pathological diagnosis can be difficult. In the literature two cases of EHE were found to harbor a balanced t(1;3)(p36.3;q25) translocation, suggesting a characteristic chromosomal rearrangement as cause for the development of EHE. In this study, 14 cases of EHE were investigated by interphase fluorescence in situ hybridization (FISH) directed against the translocation breakpoint 1p36.3. A subset of cases was also analyzed by comparative genomic hybridization (CGH) and image cytometry. Five out of eight cases that could be successfully analyzed by FISH harbored a chromosomal break in the 1p36.3 region. The break-apart signals were present in diploid nuclei, and less frequently also in tetraploid nuclei. In the latter, the chromosomal break was present twice, suggesting that polyploidy occurred after the chromosomal alteration. DNA cytometry confirmed that tetraploid cells were present in most examined cases with one case indicating almost equal amounts of diploid and tetraploid tumor cells. CGH revealed single chromosomal imbalances of unclear significance. We could confirm that EHE may harbor a recurrent mutation involving the 1p36.3 chromosomal region thus supporting the notion that the t(1;3)(p36.3;q25) translocation is a relevant genetic finding in this tumor entity.

TLE1 is a robust diagnostic biomarker for synovial sarcomas and correlates with t(X;18): analysis of 319 cases.

INTRODUCTION: Genomewide expression profiling has identified a number of genes expressed at higher levels in synovial sarcoma than in other sarcomas. Our objectives in this study were (1) to test whether the differentially expressed gene, Transducin-Like Enhancer of split (TLE1) belonging to the groucho/TLE family, is also distinct on the protein level; (2) to evaluate this biomarker in a series of well-characterised synovial sarcomas on standard, full-sized tissue sections and (3) to correlate the expression of TLE1 with t(X;18) and other established biomarkers. METHODS: Three-hundred and eighty four spindle cell sarcomas from the German consultation and reference centre of soft tissue tumours initially suspected for synovial sarcoma were revisited. Three-hundred and nineteen of these specimens were analysed immunohistochemically using a monoclonal antibody TLE1 and standard, full-sized tissue sections. The nuclear staining was scored semiquantitatively as -, negative; +, weak; ++, moderate and +++, strong positive. Furthermore, 118 specimens among these were further analysed using FISH and/or PCR to detect t(X;18). We correlated the TLE1 expression with the t(X;18) translocation and other established biomarkers (EMA, PanCK, CK7, CD34 and BCL2). RESULTS: TLE1 expression was observed in 96% of the synovial sarcomas (score+, 249/259) and discriminates them from other soft tissue tumours (p<0.001). Multivariate analysis showed that positive TLE1 staining was a statistically independent diagnostic marker. Furthermore molecular analysis showed that t(X;18) was clearly correlated with TLE1 protein expression (p<0.001). CONCLUSIONS: Expression of TLE1 is significantly correlated with t(X;18) and may serve as a new robust diagnostic biomarker in synovial sarcomas and potential therapeutic target.

Soft tissue tumors: new perspectives on classification and diagnosis.

BACKGROUND: In recent years, new tumor entities have been described and previously known tumor types have undergone a reassessment. This article offers an overview of recent developments in the classification and interpretation of soft tissue tumors. METHODS: Selective review of publications from 1990 until 2008 from the literature database of the Consultation and Referral Center for Soft Tissue Tumors in Jena. The current status of the classification and morphological diagnosis of these tumors is described. RESULTS: The description of the biological behavior of soft tissue tumors has become more detailed with the introduction of two intermediate categories ("intermediate, locally aggressive" and "intermediate, rarely metastasizing"). There have also been some changes in terminology. Previously established terms such as "malignant fibrous histiocytoma" or "hemangiopericytoma" will be used much less often in future, because these tumor types have been reinterpreted. The WHO recommends that highly differentiated liposarcoma be renamed "atypical lipomatous tumor." Molecular diagnostic techniques have become firmly established as an ancillary diagnostic method. The importance of molecular tumor characterization for individually tailored therapy is already becoming clear. CONCLUSIONS: Optimal diagnosis is the prerequisite for effective therapy and can be achieved only with state-of-the-art knowledge of the pathology of soft tissue tumors.

Hemangioma of the mandible: case report with special emphasis on bone degradation.

PURPOSE: Intraosseous hemangioma of the mandible is a rare tumor. In this report, we present a case with a particularly prominent osteolysis and discuss the histological features of bone degradation. MATERIALS AND METHODS: We describe a 64-year-old female patient with a cystic tumor mass of the mandible leading to pathologic bone fracture. X-ray analysis was suggestive for aneurysmatic bone cyst. A segment resection was performed. RESULTS: The histological examination revealed a mesenchymal tumor with numerous capillaries and dilated vessels immunohistochemically being positive for CD31, but not for D2-40. In addition, there was a remarkable increase of osteoclasts that sometimes exhibited Howship's lacunae. The tumor was diagnosed as intraosseous hemangioma with prominent bone degradation. CONCLUSIONS: Based on our histological findings, it should be further investigated whether there could be an association between angiogenesis and osteoclastogenesis as a central pathway leading to bone destruction in the case of intraosseous hemangiomas.

Melanocytic schwannoma of the cutaneous and subcutaneous tissues: three cases and a review of the literature.

Melanocytic schwannoma is a rare soft-tissue tumor, which arises most commonly in the paraspinal sympathetic chain. In general, 25% of the patients develop metastasis. To date, only 17 cases of a cutaneous and subcutaneous melanocytic schwannoma have been reported. None of these patients developed metastasis. Three cases of cutaneous melanocytic schwannoma, diagnosed in our institution are reported. For further literature overview we performed a search on Medline using the terms 'melanocytic schwannoma' or 'melanotic schwannoma' or 'Carney complex' combined with 'skin' or 'cutaneous', for the period 1970-2007. Seventeen patients were described to have melanocytic schwannoma of the skin or subcutaneous tissues. These papers were reviewed for clinical data. Two of the three patients showed metastatic disease, one of them died of disseminated metastases. In contrast, none of the reported cases of cutaneous or subcutaneous melanocytic schwannomas was characterized by a malignant course. The differential diagnosis, especially with regard to malignant melanoma, is made by histology and by its clinical course, which differs from melanoma in its tendency to recur at the site of excision and slow rate of growth. Commonly misdiagnosed as melanoma, this tumor reveals insights into the origin of both melanocytes and Schwann cells. It is likely that the biological bases for melanoma and melanocytic schwannoma differ. It is necessary to differentiate this tumor from melanoma because of the differing prognosis and the association of melanocytic schwannoma with the Carney complex. Owing to the lack of clinical trials, we recommend that patients be treated according to the existing guidelines for melanoma.

Complex formation of the laminin-5 gamma2 chain and large unspliced tenascin-C in oral squamous cell carcinoma in vitro and in situ: implications for sequential modulation of extracellular matrix in the invasive tumor front.

Invasion and metastasis in oral squamous cell carcinoma (OSCC) are associated with changes in the extracellular matrix (ECM). We have previously shown an extracellular co-deposition of laminin-5 (Ln-5) and large unspliced tenascin-C (Tn-C(L)) in OSCC. Using a co-culture model of hTERT-BJ1 fibroblasts and the OSCC cell line PE/CA-PJ15, we demonstrate in the present study that Ln-5 and Tn-C(L) are not only co-deposited, but also form a physical complex which can be recovered by co-immunoprecipitation. In agreement with these results, examination of OSCC tissue specimens of different malignancy grade by means of confocal laser scanning microscopy revealed different patterns of Ln-5 and Tn-C(L) co-localization implicating complex formation also in vivo. A ribbon like co-localization was detected in subepithelial basement membranes around well differentiated OSCC parts and tumor clusters. Furthermore, a fibrillar Ln-5 gamma2 chain/Tn-C(L) co-localization occurred in the carcinoma stroma beneath tumor clusters. Additionally, at the site of ruptured basement membranes there were dot or strand like co-deposits of both molecules, but co-localizations were only rarely detectable. These different patterns may reflect a sequential modulation and reorganization of the ECM in the tumor/stroma interface as it occurs in different stages of OSCC invasion.