Erik Springer

Actinomycosis of the jaws—histopathological study of 45 patients shows significant involvement in bisphosphonate-associated osteonecrosis and infected osteoradionecrosis

Actinomycosis of the jaws is a rare disease, which has been recently described in patients with infected osteoradionecrosis (IORN) and bisphosphonate-associated osteonecrosis (BON). We investigated our archive material for Actinomycosis of the jaws with special regard to underlying disease. Out of a total number of 45 patients with Actinomycosis, 43 (93.5%) suffered from BON (58.7%) or IORN (35.6%), while there were only 3 patients (6.7%) without anti-tumor treatment. In all cases, we found direct association of Actinomyces colonies with bone; in the surrounding medullary space, mixed inflammatory infiltrates with variable amounts of osteoclasts were a typical finding. Pseudoepitheliomatous hyperplasia occurred in 60.9% of patients. Cell-rich vessel obliteration was seen in less than 25.9% of BON patients, while hyalinized vessel obliteration was obtained in 37.5% of IORN patients. Additionally performed polymerase chain reaction (PCR) on paraffin-embedded and ethylene diamine tetracetic acid (EDTA)-decalcified tissue specimens confirmed the presence of Actinomyces israelii in seven of seven cases analyzed. We conclude that Actinomycosis of the jaws is a particular complication in patients with BON and/or IORN. Patients with Actinomycosis of the jaws during or after these forms of anti-cancer therapy are suggested to represent a distinct patient cohort with a relevant impairment of their general condition.

PCR testing for Treponema pallidum in paraffin- embedded skin biopsy specimens: test design and impact on the diagnosis of syphilis

Background: Syphilis, a chronic infection caused by Treponema pallidum, is a disease which is increasing in incidence, and thus more and more becoming a differential diagnosis in routine pathology. Aims: To develop a PCR-based molecular assay for the detection of T pallidum in formalin-fixed, paraffin-embedded tissues, and evaluate its diagnostic power, especially in comparison with other ancillary methods (immunohistochemistry and Dieterle staining). Methods: 36 skin biopsy specimens with the clinical and/or serological diagnosis of syphilis were evaluated by morphology, immunohistochemistry and silver staining. A semi-nested PCR assay targeting the T pallidum DNA polymerase A gene was designed and applied. Specificity of amplification was confirmed by direct sequencing of PCR products. Results: Overall, the presence of T pallidum was detected in skin biopsy specimens in 20 cases, by immunohistochemistry, Dieterle staining, or PCR. Immunohistochemistry testing was positive in 17/35 cases tested, and Dieterle staining in 9/35 cases tested. In comparison, PCR testing was positive in 14/36 cases, and highly dependent on the tissue quality. When excluding cases with compromised DNA quality, PCR testing was positive in all cases except one, including three cases negative by immunohistochemistry and Dieterle staining. Conclusions: PCR testing is significantly more sensitive than silver staining, and provided that DNA quality is sufficient, at least as sensitive as immunohistochemistry for the detection of T pallidum in formalin-fixed, paraffin-embedded skin biopsy specimens. Therefore, it is a useful ancillary tool in the histological diagnosis of syphilis.

Oropharyngeal lesions and cervical lymphadenopathy: syphilis is a differential diagnosis that is still relevant.

Background Syphilis (lues), a chronic infectious disease caused by Treponema pallidum, has been increasing in incidence during the last few years. Therefore, while clinically it is often not suspected, syphilis is increasingly becoming a differential diagnosis in routine pathology. Aim To report our experience with five cases of cervical lymphadenopathy and/or oropharyngeal lesions, clinically thought to be lymphomas, lymph node metastases or carcinoma, in which we made the mostly clinically unsuspected diagnosis of syphilis. Methods Fine needle aspiration of enlarged cervical lymph nodes was evaluated by cytology and flow cytometry (fluorescence-activated cell sorting analysis), and biopsies were examined by using histology. In addition, all materials were also subjected to immunostaining, silver staining and molecular (PCR) testing. Results Fine needle aspiration cytology revealed follicular hyperplasia in two cases and granulomatous lymphadenitis in one case. In three patients, concomitant biopsy of co-existing oropharyngeal lesions revealed histological findings compatible with syphilis. T pallidum was detected in all cytological and histological samples by immunohistochemistry/immunocytochemistry and PCR. Subsequently, a diagnosis of syphilis was confirmed clinically and by serology. Conclusions Syphilitic lymphadenitis is still a relevant differential diagnosis of cervical lymphadenopathy, and it is clinically often not suspected. Co-exisiting oropharyngeal lesions should alert the physician to this differential diagnosis; and lesions with compatible morphology should be tested with immunohistochemistry and immunocytochemistry and/or molecular analysis to confirm the diagnosis of syphilis.

Bone marrow findings in multicentric Castleman disease in HIV-negative patients.

Because bone marrow histology in multicentric Castleman disease in human immunodeficiency virus-negative patients is not well reported, we investigated sequential bone marrow biopsies of 3 affected human immunodeficiency virus-negative patients, of which one was human herpes virus 8 (HHV8)-positive. The histologic evaluation of the bone marrow revealed lymphoid follicles with regressed germinal centers in 1 patient. Another patient showed tumorlike but bland polyclonal plasmacytosis with large perivascular plasma cell clusters. The HHV8-positive patient revealed interstitial HHV8-positive cells accompanied by a mild plasmacytosis. The atypical lymphoid follicles could be regarded as a bone marrow manifestation of multicentric Castleman disease, whereas the plasmacytosis most likely is the result of excess interleukin 6 production. The presence of HHV8-positive cells within the bone marrow may indicate the dissemination of the virus in a compromised immune system.

Phenotypic variability and risk of malignancy in SDHC-linked paragangliomas: lessons from three unrelated cases with an identical germline mutation (p.Arg133*).

CONTEXT Mutations in the four subunits of succinate dehydrogenase (SDH) are the cause for the hereditary paraganglioma (PGL) syndrome types 1-4 and are associated with multiple and recurrent pheochromocytomas and PGLs. SDHC mutations most frequently result in benign, nonfunctional head-and neck PGLs (HNPGLs). The malignant potential of SDHC mutations remains unclear to date. OBJECTIVES We report a patient with malignant PGL carrying a SDHC mutation and compare her case with two others of the same genotype but presenting with classic benign HNPGLs. Loss of heterozygosity (LOH) was demonstrated in the malignant PGL tissue. DESIGN In three unrelated patients referred for routine genetic testing, SDHB, SDHC, and SDHD genes were sequenced, and gross deletions were excluded by multiplex ligation-dependent probe amplification (MLPA). LOH was determined by pyrosequencing-based allele quantification and SDHB immunohistochemistry. RESULTS In a patient with a nonfunctioning thoracic PGL metastatic to the bone, the lungs, and mediastinal lymph nodes, we detected the SDHC mutation c.397C>T predicting a truncated protein due to a premature stop codon (p.Arg133*). We demonstrated LOH and loss of SDHB protein expression in the malignant tumor tissue. The two other patients also carried c.397C>T, p.Arg133*; they differed from each other with respect to their tumor characteristics, but both showed benign HNPGLs. CONCLUSIONS We describe the first case of a malignant PGL with distant metastases caused by a SDHC germline mutation. The present case shows that SDHC germline mutations can have highly variable phenotypes and may cause malignant PGL, although malignancy is probably rare.

The TFIIH Subunit p89 (XPB) Localizes to the Centrosome during Mitosis

Background: The general transcription factor II H (TFIIH), comprised of a core complex and an associated CAK-complex, functions in transcription, DNA repair and cell cycle control. Mutations of the two largest subunits, p89 (XPB) and p80 (XPD), cause the hereditary cancer-prone syndrome xeroderma pigmentosum. Methods: The TFIIH subunit p89 was monitored during interphase and cell division by immunofluorescence staining, GFP-fusion constructs including deletions, live cell imaging and immuno-precipitations. Results: Here we demonstrate that during cell division, from prophase until telophase, the TFIIH core subunit p89, but not other subunits of TFIIH, associates with the centrosomes and the adjacent parts of the mitotic spindle. With overall constant levels throughout mitosis, p89 re-localizes to the newly formed nuclei by the end of mitosis. Furthermore, p89 interacts with the centrosomal protein γ-tubulin. Truncations of p89 result in an abnormal subcellular distribution during interphase and abolished centrosomal association during mitosis. Conclusions: Our observations suggest a so far unappreciated role for p89 in cell cycle regulation, and may be the structural basis for a long known, but hitherto unexplained interaction between p89 and tubulin.

Hepatitis E Virus Detection in Liver Tissue from Patients with Suspected Drug-Induced Liver Injury

Hepatitis E virus (HEV) infection is increasingly recognized as a cause of acute hepatitis in the industrialized world. We aimed to determine the frequency of acute HEV infection in cases of suspected drug-induced liver injury (DILI), mainly a diagnosis of exclusion. To this aim, formalin-fixed paraffin-embedded (FFPE) liver tissues of all cases routinely processed in our institute during a 2 1/2 years period in which DILI was among the differential diagnoses (157 liver biopsies, 1 liver explant) were subjected to semi-nested RT-PCR for the detection of HEV RNA. Histopathology was re-evaluated on all cases tested positive. HEV RNA was detectable in 3 of 158 cases (2%) tested, comprising autochthonic as well as travel-related infections with genotypes 1, 3, and 4 each found once, respectively. Histopathologic findings comprised one case with subtotal hepatic necrosis and two cases of acute (cholestatic) hepatitis not distinguishable from acute hepatitis of other etiology. Thus, the overall frequency of acute HEV infection as determined by detection of HEV RNA in liver tissue is substantially increased in patients with suspected DILI compared to the healthy population, emphasizing the need to actively look for HEV infection in cases of suspected DILI. Molecular testing for HEV RNA in routinely processed FFPE liver tissues can be applied to cases with undetermined HEV status.

Biomaterial-induced sarcomagenesis is not associated with microsatellite instability

Sarcomagenesis, in contrast to carcinogenesis, is poorly understood. Microsatellite instability has been implicated in the development of many cancers, in particular those associated with chronic inflammatory conditions. In an experimental animal model, rats developed not only a peri-implantational chronic inflammatory reaction, but also malignant mesenchymal tumors in response to different biomaterials. Therefore, it was the aim of our study to test if the development of biomaterial-induced sarcomas is characterized by a mutator phenotype. A multiplex-PCR approach was designed to screen biomaterial-induced sarcomas for the presence of microsatellite instability. Seven different microsatellite loci were tested in ten tumors for microsatellite instability using a fluorochrome-labelled multiplex-PCR and subsequent fragment analysis. All tumors provided a microsatellite-stable phenotype at all loci tested. Our data suggest that microsatellite instability is rarely or not at all a feature of malignant transformation of biomaterial-induced soft tissue tumors. Thus, there is no evidence that a mutator phenotype is a hallmark of biomaterial-induced sarcomagenesis.

JAK2-V617F-mutated myeloproliferative neoplasms reveal different allele burden within hematopoietic cell lineages: a microdissection study of bone marrow trephine biopsies

The JAK2-V617F mutation is prevalent in almost all patients with polycythemia vera (PV) and about half of the cases of essential thrombocythaemia (ET) and primary myelofibrosis (PMF). A different allele burden in these entities has long been noticed, but little is known about its distribution among the neoplastic hematopoietic cell lineages within the bone marrow. We conducted a microdissection study of JAK2-V617F-mutated myeloproliferative neoplasms (MPN); 10 cases each of ET, PV, and PMF, with separate analysis of the JAK2 mutation status in three hematopoietic cell lines (i.e., megakaryo-, granulo-, and erythropoiesis). Different numbers of cell lineages harboring the JAK2-V617F mutation were found, being the lowest in ET (17/30), higher in PV (24/30) and in PMF (22/30). The megakaryopoiesis was the most commonly mutated cell lineage (24/30 cases). By analyzing microdissectates we were able to demonstrate a different allele burden of the JAK2-V617F mutation in the megakaryo-, erythro-, and granulopoiesis within the bone marrow of a given case of MPN. We demonstrated differences in the number of mutated cell lineages. The different mutation status may contribute to the different phenotypes of ET, PV, and PMF.

Wild-type JAK2 secondary acute erythroleukemia developing after JAK2-V617F-mutated primary myelofibrosis.

A 54-year-old female patient developed acute erythroleukemia after an 8-year course of primary myelofibrosis. The latter harbors the JAK2-V617F mutation and was treated with hydroxyurea and anagrelide. A bone marrow trephine biopsy disclosed 2 morphologically distinct areas of chronic primary myelofibrosis and acute erythroleukemia. Microdissection and a separate molecular pathological analysis was performed. Although the activating JAK2-V617F mutation was not maintained in blasts of acute erythroleukemia, it was detectable in the chronic phase of primary myelofibrosis, indicating that this mutation did not play a role in the leukemic transformation of erythroid cells.