Bovine papillomavirus type 2 infection and a series of mesenchymal tumors of the urinary bladder in cattle.

This report describes the histopathology of two hundred and fifty-three mesenchymal tumors of the urinary bladder in cattle grazing on lands rich in bracken fern. Approximately 80% were hemangiomas and angiosarcomas. Hemangioma (capillary, cavernous, and large vessels) was the most frequent mesenchymal tumor and was more common than angiosarcoma. Although the appearance of endothelial cells can vary remarkably, epithelioid angiosarcomas, often containing multinucleated cells, were the most frequent malignant vascular tumors. Hemangiopericytoma and tumors of muscle and soft connective tissue origin, alone and/or in association with tumor-like lesions, were less frequently seen. Furthermore, forty-five cases of intravascular papillary endothelial hyperplasia (IPEH), a lesion not previously reported in the urinary bladder of cattle, were also described. Bovine papillomavirus type-2 DNA was amplified in tumor samples. Forty vascular tumors were investigated by dual-labeling immunofluorescence, and, for the first time, a coexpression of E5 and platelet-derived growth factor ß receptor (PDGF ß R) was shown to occur. The results show that the BPV-2 E5 oncoprotein binds to the activated form of the PDGF ß receptor thus playing an important role in mesenchymal as well as epithelial carcinogenesis of the urinary bladder. Furthermore, these findings demonstrate that BPV-2 infects both epithelial and mesenchymal cells.

Study of HHV-8 DNA sequences in archival biopsies from lesional skin of Kaposi's sarcoma, various mesenchymal tumors and related reactive conditions.

BACKGROUND: HHV-8 has been identified as the causative agent of Kaposi's sarcoma (KS) and some lymphoproliferative disorders. In addition, there are anecdotal reports on the presence of HHV-8 in other tumors, especially cutaneous epithelial and mesenchymal neoplasms. The aim of the study was to ascertain the value of identification of HHV-8 viral DNA sequences in routinely processed, formalin-fixed, paraffin-embedded tissues for the diagnosis of Kaposi's sarcoma and other mesenchymal tumors. METHODS: The presence of HHV-8 sequences in archival material was studied by nested PCR using specific primers for amplification of a 233-bp long fragment of HHV-8 (ORF 26). RESULTS: Thirty-three patients with KS (18 classic/sporadic, six post-transplant and nine AIDS-related) and various mesenchymal tumors and related conditions (n = 76) were studied. HHV-8 DNA sequences were detected in 29 of the 33 cases of KS and in one case of multiple eruptive dermatofibroma (MEDF). CONCLUSIONS: Identification of HHV-8 DNA sequences in routinely processed tissue is a useful diagnostic marker for KS. Although other mesenchymal tumors are usually not associated with HHV-8, its presence is not fully specific for KS since HHV-8 sequences were also found in one case of MEDF. Therefore, PCR analysis for the detection of HHV-8 should only be used as an additional diagnostic marker for KS and in the context of other tools such as routine histology.

Oesophageal mesenchymal tumours: clinicopathological features and absence of Epstein-Barr virus.

BACKGROUND: Recent studies have suggested that the Epstein-Barr virus (EBV) is associated with smooth muscle tumours (leiomyoma and leiomyosarcoma) in patients with human immunodeficiency virus and in organ transplant recipients. Leiomyoma is the most common mensenchymal tumour found in the oesophagus. AIM: To report a single institution experience on oesophageal mesenchymal tumours and to determine whether EBV is associated with these tumours. METHODS: 40 sporadic oesophageal mesenchymal tumours were studied and their diagnosis confirmed on pathological review and immunohistochemical studies. Formalin fixed, paraffin was embedded tissues from these tumours were analysed for EBV using in situ hybridisation for two messenger RNA (mRNA) probes, EBER and BamH1 W. RESULTS: The oesophageal mesenchymal tumours comprised 36 leiomyomas, two undifferentiated stromal tumours, and two gastrointestinal autonomic nerve tumours (GANTs). Median age of the patients with leiomyoma (26 men, 10 women) was 62 years (range 30 to 85) and 81% of them had an asymptomatic lesion. The median longitudinal size was 1.2 cm. Multiple leiomyomas were seen in 11% of the patients and calcification was noted in one tumour. Coexisting squamous cell carcinoma was found in one third of cases. The stromal tumours were small, asymptomatic, and located in the lower third of the oesophagus, while the GANTs were large, symptomatic, and found in the upper third of the oesophagus. EBV mRNAs were not detected in all these tumours. CONCLUSIONS: The clinicopathological features of oesophageal leiomyoma, undifferentiated stromal tumour, and GANT were different. Some oesophageal leiomyomas were associated with oesophageal squamous cell carcinomas. EBV is not associated with sporadic oesophageal mesenchymal tumours.

Detection of Epstein-Barr Virus in inflammatory pseudotumor.

Inflammatory pseudotumors appear to represent a heterogeneous group of diseases that share common histopathologic features. A subset of these tumors, particularly those in the spleen and liver, harbor the Epstein-Barr virus (EBV) in spindled cells. Methods for detecting EBV in these tumors and the reliability of the different detection methods are discussed. Some EBV-positive inflammatory pseudotumors contain an increase in EBV-positive follicular dendritic cells and demonstrate monoclonal EBV genomes. At least one such case has recurred locally as an unusual EBV-positive follicular dendritic cell tumor. These rare reports support the concept of a distinct EBV-positive, follicular dendritic cell type of inflammatory pseudotumor that may be at increased risk for local recurrence. Many more cases of this rare type of inflammatory pseudotumor must be studied and reported before the clinical validity of such a distinction can be proven. Although EBV detection in spindled cells is unusual, it has been demonstrated in rare smooth muscle tumors arising in immunosuppressed children and young adults.

[Detection of herpes virus-like DNA in various forms of Kaposi's sarcoma but not in other mesenchymal tumors or inflammatory changes in skin]. / Nachweis von Herpes-Virus ähnlicher DNA in den verschiedenen Formen des Kaposi Sarkoms aber nicht in anderen mesenchymalen Tumoren oder entzündlichen Veränderungen der Haut.

Recently, herpes-virus like DNA sequences defining a new herpes virus termed human herpes virus 8 (HHV8), were detected in Kaposi's sarcoma of AIDS and non-AIDS patients. We describe the successful detection of HHV8 DNA in archival skin biopsies of the various forms of Kaposi's sarcoma. DNA was extracted from archival skin biopsies of Kaposi's sarcoma, other mesenchymal skin tumors and various inflammatory skin lesion of HIV seropositive and negative patients. The extracted DNA was analyzed for the presence of HHV8 DNA using a nested PCR assay. All samples were tested for the presence of appropriate DNA using a internal cellular control PCR-reaction. A total of 23 Kaposi's sarcoma were analyzed, including 12 of the endemic type, 9 HIV-associated and 2 transplant related. HHV8 DNA was detected by nested PCR in all forms of Kaposi's sarcoma. In contrast, no HHV8 DNA could be found in 17 mesenchymal, especially vascular skin tumors or in 7 biopsies with unspecific inflammatory skin lesions of HIV seropositive and negative patients. HHV8 DNA was present in all forms of Kaposi's sarcoma tested but not in other mesenchymal tumors or unspecific inflammatory lesions of the skin. This data support the idea of a strong association of HHV8 and Kaposi's sarcoma.