[Diagnostic problems in testicular tumours in consultant pathology : A practical guide]. / Diagnostische Probleme bei Hodentumoren in der Konsiliarpathologie : Ein praktischer Leitfaden.

The great variety of pathological patterns in germ cell tumours, especially in yolk sac tumours but also the possibility of somatic-type malignancies, can complicate daily diagnosis. For the correct diagnosis, knowledge of morphological aspects and additional immunohistochemical staining can be helpful. Also, rare entities like sex cord stromal tumours, tumours of testicular adnexa or mesenchymal tumours of the spermatic cord can be diagnostically challenging.

Management of Germ Cell Tumours of the Testis in Adult Patients. German Clinical Practice Guideline Part I: Epidemiology, Classification, Diagnosis, Prognosis, Fertility Preservation, and Treatment Recommendations for Localized Stages.

INTRODUCTION: This is the first German evidence- and consensus-based clinical guideline on diagnosis, treatment, and follow-up on germ cell tumours (GCTs) of the testis in adult patients. We present the guideline content in two publications. Part I covers the topic's background, methods, epidemiology, classification systems, diagnostics, prognosis, and treatment recommendations for the localized stages. METHODS: An interdisciplinary panel of 42 experts including 1 patient representative developed the guideline content. Clinical recommendations and statements were based on scientific evidence and expert consensus. For this purpose, evidence tables for several review questions, which were based on systematic literature searches (last search was in March 2018) were provided. Thirty-one experts entitled to vote, rated the final clinical recommendations and statements. RESULTS: We provide 161 clinical recommendations and statements. We present information on the quality of cancer care and epidemiology and give recommendations for staging and classification as well as for diagnostic procedures. The diagnostic recommendations encompass measures for assessing the primary tumour as well as procedures for the detection of metastases. One chapter addresses prognostic factors. In part I, we separately present the treatment recommendations for germ cell neoplasia in situ, and the organ-confined stages (clinical stage I) of both seminoma and nonseminoma. CONCLUSION: Although GCT is a rare tumour entity with excellent survival rates for the localized stages, its management requires an interdisciplinary approach, including several clinical experts. Quality of care is highly related to institutional expertise and can be reassured by established online-based second-opinion boards. There are very few studies on diagnostics with good level of evidence. Treatment of metastatic GCTs must be tailored to the risk according to the International Germ Cell Cancer Collaboration Group classification after careful diagnostic evaluation. An interdisciplinary approach as well as the referral of selected patients to centres with proven experience can help achieve favourable clinical outcomes.

Management of Germ Cell Tumours of the Testes in Adult Patients: German Clinical Practice Guideline, PART II - Recommendations for the Treatment of Advanced, Recurrent, and Refractory Disease and Extragonadal and Sex Cord/Stromal Tumours and for the Management of Follow-Up, Toxicity, Quality of Life, Palliative Care, and Supportive Therapy.

OBJECTIVES: We developed the first German evidence- and consensus-based clinical guideline on diagnosis, treatment, and follow-up of germ cell tumours (GCT) of the testes in adult patients. We present the guideline content in 2 separate publications. The present second part summarizes therecommendations for the treatment of advanced disease stages and for the management of follow-up and late effects. MATERIALS AND METHODS: An interdisciplinary panel of 42 experts including 1 patient representative developed the guideline content. Clinical recommendations and statements were based on scientific evidence and expert consensus. For this purpose, evidence tables for several review questions, which were based on systematic literature searches (last search in March 2018), were provided. Thirty-one experts, who were entitled to vote, rated the final clinical recommendations and statements. RESULTS: Here we present the treatment recommendations separately for patients with metastatic seminoma and non-seminomatous GCT (stages IIA/B and IIC/III), for restaging and treatment of residual masses, and for relapsed and refractory disease stages. The recommendations also cover extragonadal and sex cord/stromal tumours, the management of follow-up and toxicity, quality-of-life aspects, palliative care, and supportive therapy. CONCLUSION: Physicians and other medical service providers who are involved in the diagnostics, treatment, and follow-up of GCT (all stages, outpatient and inpatient care as well as rehabilitation) are the users of the present guideline. The guideline also comprises quality indicators for measuring the implementation of the guideline recommendations in routine clinical care; these data will be presented in a future publication.

The detection of isochromosome i(12p) in malignant germ cell tumours and tumours with somatic malignant transformation by the use of quantitative real-time polymerase chain reaction.

AIMS: Malignant germ cell tumours (GCTs) of the testis are rare neoplasms, but the most common solid malignancies in young men. World Health Organization guidelines divide GCTs into five types, for which numerous immunohistochemical markers allow exact histological subtyping in the majority of cases. In contrast, a germ cell origin is often hard to prove in metastatic GCTs that have developed so-called somatic malignant transformation. A high percentage, up to 89%, of GCTs are characterised by the appearance of isochromosome 12p [i(12p)]. Fluorescence in-situ hybridisation has been the most common diagnostic method for the detection of i(12p) so far, but has the disadvantages of being time-consuming, demanding, and not being a stand-alone method. The aim of the present study was to establish a quantitative real-time polymerase chain reaction assay as an independent method for detecting i(12p) and regional amplifications of the short arm of chromosome 12 by using DNA extracted from formalin-fixed paraffin-embedded tissue. METHODS AND RESULTS: A cut-off value to distinguish between the presence and absence of i(12p) was established in a control set consisting of 36 tumour-free samples. In a training set of 149 GCT samples, i(12p) was detectable in 133 tumours (89%), but not in 16 tumours (11%). In a test set containing 27 primary and metastatic GCTs, all 16 tumours with metastatic spread and/or somatic malignant transformation were successfully identified by the detection of i(12p). CONCLUSION: In summary, the qPCR assay presented here can help to identify, further characterise and assign a large proportion of histologically inconclusive malignancies to a GCT origin.

Ovarian-type epithelial tumours of the testis: immunohistochemical and molecular analysis of two serous borderline tumours of the testis.

Tumours of ovarian-epithelial type of the testis, including serous borderline tumours, represent very rare entities. They are identical to the surface epithelial tumours of the ovary and have been reported in patients from 14 to 68 years of age. We describe two cases of a 46- and a 39-year old man with incidental findings of intratesticular masses of the left respectively right testis. Under the assumption of a malignant testicular tumour the patients were subjected to inguinal orchiectomy. Histologically, the tumours were identical to their ovarian counterparts: They showed a cystic configuration with a fibrous wall and irregular papillary structures lined by partially multistratified columnar cells and areas of hobnail cells. Furthermore, there was mild cytological atypia with a proliferative activity of below 5% as proved by Ki67 staining; mitoses could not be detected. Immunohistochemically, the tumour cells displayed expression of pan-cytokeratin AE3, progesterone receptor, Wilms' tumour protein (WT1), and PAX8 (Paired box gene 8). Estrogen receptor was expressed in one case. Octamer-binding transcription factor-4 (OCT4), calretinin, thrombomodulin, and D2-40 were not expressed. Mutation testing of BRAF revealed a BRAF V600E mutation in one case, while testing for KRAS mutations proved to be negative in both. The BRAF mutated tumour showed strong cytosolic and membranous positivity for B-Raf also on immunohistochemical analysis. Comparative genomic hybridization of one case could not reveal any chromosomal aberrations.

CK19 is a sensitive marker for yolk sac tumours of the testis.

BACKGROUND: Malignant germ cell tumours are the most common malignant tumours in young men. They are histologically divided into seminomas and non-seminomas. Non-seminomas are further subdivided into embryonic carcinomas, yolk sac tumours, chorionic carcinomas, and teratomas. For the therapeutic management it is essential to differentiate between these histological subtypes. METHODS: Investigated cases included normal testis (n = 50), intratubular germ cell neoplasia (n = 25), seminomas (n = 67), embryonic carcinomas (n = 56), yolk sac tumours (n = 29), chorionic carcinomas (n = 2), teratomas (n = 7) and four metastases of YST's for their CK19 expression. In addition Leydig cell- (n = 10) and Sertoli cell- tumours (n = 4) were included in this study. RESULTS: All investigated seminomas, embryonic carcinomas as well as normal testis and intratubular germ cell neoplasias did not express CK19. In contrast, all investigated yolk sac tumours strongly expressed CK19 protein. These findings became also evident in mixed germ cell tumours consisting of embryonic carcinomas and yolk sac tumours, although CK19-expression could also be observed in analysed chorionic carcinomas and epithelial components of teratomas. CONCLUSION: CK19 proved to be a sensitive marker to identify yolk sac tumours of the testis and to distinguish them from other germ cell tumours, especially seminomas and embryonic carcinomas. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4075546891400979.

Inactivation of patched1 in murine chondrocytes causes spinal fusion without inflammation.

OBJECTIVE: During development of the vertebrate skeleton, chondrocytes form a cartilage template that is gradually replaced by bone. Hormones of the Hedgehog (HH) family have been implicated in the ossification process, but their exact relationship to normal or pathogenic bone formation is unclear. This study was undertaken to establish a genetic tool that allows the discrete inactivation of genes in spinal chondrocytes, and to investigate in vivo how chondrocyte-specific ablation of the inhibitory HH receptor Patched 1 (Ptch1) affects skeleton integrity. METHODS: A Cre-deleter mouse strain, mb1-Cre, for selective gene recombination in spinal chondrocytes was identified by in situ hybridization and histologic analysis. The mb1-Cre(+/-) animals were crossed with mice that harbor a loxP-flanked Ptch1 gene (Ptch1(flox/flox) ) to abrogate the inhibition of the HH signaling pathway in chondrocytes. The skeletal integrity of F1 mice was characterized by high-resolution flat-panel-based volume computed tomography and histologic staining procedures. RESULTS: During the first weeks after birth, all mb1-Cre(+/-) /Ptch1(flox/flox) mice developed progressive spinal fusion with malformation of the vertebrae. This phenotype was caused by aberrant chondrocyte proliferation in the intervertebral discs that blocked endochondral ossification. Importantly, the disease pattern occurred in an inflammation-independent manner. CONCLUSION: Our findings indicate that chronic activation of the HH signal pathway in spinal chondrocytes can trigger an ankylosing spine morphology without immune cell contributions. Hence, the destruction of cartilage and loss of axial joint integrity can result from chondrocyte-intrinsic defects of monogenic origin.

Phytoestrogens regulate the proliferation and expression of stem cell factors in cell lines of malignant testicular germ cell tumors.

Phytoestrogens have been shown to exert anti-proliferative effects on different cancer cells. In addition it could be demonstrated that inhibition of proliferation is associated with downregulation of the known stem cell factors NANOG, POU5F1 and SOX2 in tumor cells. We demonstrate the potential of Belamcanda chinensis extract (BCE) and tectorigenin as anticancer drugs in cell lines of malignant testicular germ cell tumor cells (TGCT) by inhibition of proliferation and regulating the expression of stem cell factors. The TGCT cell lines TCam-2 and NTera-2 were treated with BCE or tectorigenin and MTT assay was used to measure the proliferation of tumor cells. In addition, the expression of stem cell factors was analyzed by quantitative PCR and western blot analysis. Furthermore, global expression analysis was performed by microarray technique. BCE and tectorigenin inhibited proliferation and downregulated the stem cell factors NANOG and POU5F1 in TGCT cells. In addition, gene expression profiling revealed induction of genes important for the differentiation and inhibition of oncogenes. Utilizing connectivity map in an attempt to elucidate mechanism underlying BCE treatments we found highly positive association to histone deacetylase inhibitors (HDACi) amongst others. Causing no histone deacetylase inhibition, the effects of BCE on proliferation and stem cell factors may be based on histone-independent mechanisms such as direct hyperacetylation of transcription factors. Based on these findings, phytoestrogens may be useful as new agents in the treatment of TGCT.

Sertoliform cystadenoma: a rare benign tumour of the rete testis.

Sertoliform cystadenoma of the rete testis represents an uncommon benign tumour. They appear in patients from 26 to 62 years of age. We describe a case of a 66-year-old man with a tumour in the area of the epididymal head. The tumour markers were not increased. Under the assumption of a malignant testicular tumour an inguinal orchiectomy was performed. The cut surface of this tumour was of grey/white color and showed small cysts. The tumour consisted of two compartments. The epithelial like tumour cells showed a sertoliform growth pattern and cystic dilatations. In between the tumour cells repeatedly actin expressing sclerotic areas could be recognized as the second tumour component. Proliferative activity was not increased. Immunohistochemically the tumour cells were positiv for inhibin, S-100, and CD 99. Alpha feto protein (AFP), human chorionic gonadotropin (ß-HCG) and placental alkaline phosphatase (PLAP) as well as synaptophysin, epithelial membrane antigene (EMA), and BCL-2 were not expressed. As far as we know this is the sixth reported case of this tumour. Because of the benign nature of this tumour the correct diagnosis is important for the intra- and postoperative management. Here we present a case of this rare tumour and discuss potential differential diagnosis. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1956026143857335.

13-year-old tuberous sclerosis patient with renal cell carcinoma associated with multiple renal angiomyolipomas developing multifocal micronodular pneumocyte hyperplasia.

BACKGROUND: The autosomal dominant tumor syndrome tuberous sclerosis complex is caused by the mutated TSC1 gene, hamartin, and the TSC2 gene, tuberin. Patients with this complex develop typical cutaneus symptoms such as peau chagrin or angiofibromas of the skin as well as other lesions such as astrocytomas in the brain and lymphangioleiomyomatosis in the lung. Only a few tuberous sclerosis patients have been described who showed a multifocal micronodular pneumocyte hyperplasia of the lung. Another benign tumor which often occurs together with tuberous sclerosis is the angiomyolipoma of the kidney. Furthermore, an increased incidence of renal cell carcinoma in connection with tuberous sclerosis has also been proven. CASE PRESENTATION: We report a 13-year-old white girl with epilepsy and hypopigmented skin lesions. Radiological studies demonstrated the typical cortical tubers leading to the diagnosis of tuberous sclerosis. In the following examinations a large number of angiomyolipomas were found in both kidneys. One lesion showed an increasing size and tumor like aspects in magnetic resonance imaging. The pathological examination of the following tumorectomy demonstrated an unclassified renal cell carcinoma. Four months postoperatively, a follow-up computer tomography revealed multiple bilateral pulmonary nodules. To exclude lung metastases of the renal cell carcinoma, multiple open-lung biopsies were performed. CONCLUSION: Here we report a diagnostically challenging case of a 13-year-old patient with tuberous sclerosis and angiomyolipomas of the kidney who developed an unclassified renal cell carcinoma as well as multifocal micronodular pneumocyte hyperplasia.

Valproic acid inhibits the proliferation of cancer cells by re-expressing cyclin D2.

In this study, primary murine prostate cancer (PCa) cells were derived using the well-established TRAMP model. These PCa cells were treated with the histone deacetylase inhibitor, valproic acid (VPA), and we demonstrated that VPA treatment has an antimigrative, antiinvasive and antiproliferative effect on PCa cells. Using microarray analyses, we discovered several candidate genes that could contribute to the cellular effects we observed. In this study, we could demonstrate that VPA treatment of PCa cells causes the re-expression of cyclin D2, a known regulator that is frequently lost in PCa as we could show using immunohistochemical analyses on PCa specimens. We demonstrate that VPA specifically induces the re-expression of cyclin D2, one of the highly conserved D-type cyclin family members, in several cancer cell lines with weak or no cyclin D2 expression. Interestingly, VPA treatment had no effect in fibroblasts, which typically have high basal levels of cyclin D2 expression. The re-expression of cyclin D2 observed in PCa cells is activated by increased histone acetylation in the promoter region of the Ccnd2 gene and represents one underlying molecular mechanism of VPA treatment that inhibits the proliferation of cancer cells. Altogether, our results confirm that VPA is an anticancer therapeutic drug for the treatment of tumors with epigenetically repressed cyclin D2 expression.

Embryo implantation failure and other reproductive defects in Ube2q1-deficient female mice.

The ubiquitination process is indispensable for proteome regulation. Three classes of ubiquitin (Ub)-related proteins can be distinguished: E1, E2 and E3. Proteins from the E2 class are responsible for the transfer of Ubls from E1 to the target protein. For this activity, interaction with class E3 ligases is usually required. Ub-conjugating enzyme E2Q 1 (UBE2Q1) belongs to the E2 class of Ub-related enzymes and is demonstrated to be involved in the regulation of membrane B4GALT1 protein. Here, we demonstrate that human UBE2Q1 and mouse Ube2q1 are widely expressed and highly conserved genes. To elucidate the function of UBE2Q1 protein, we generated knockout mouse model. No overt phenotype was detected in UBE2Q1-deficient males, but in mutant females, pleiotropic reproductive defects were observed including altered oestrus cycle, abnormal sexual behaviour and reduced offspring care. Moreover, in the uterus of mutant females, significantly increased embryonic lethality and decreased implantation capacity of homozygous mutant embryos were noticed. We found that Ube2q1 is not expressed in the uterus of non-pregnant females but its expression is up-regulated during pregnancy. Taken together, Ube2q1 is involved in different aspects of female fertility.

Blastomatoid pulmonary carcinosarcoma: report of a case with a review of the literature.

BACKGROUND: Pulmonary carcinosarcoma is a biphasic tumour with an unfavourable prognosis. The differential diagnosis includes pulmonary blastoma and is often challenging. CASE PRESENTATION: We here describe a case of blastomatoid pulmonary carcinosarcoma in a 58-year-old patient, who underwent surgical resection. Histopathological examination revealed immature glandular epithelium resembling high-grade fetal adenocarcinoma expressing epithelial markers and membranous beta-catenin, and blastomatoid spindle cells with partial rhabdomyosarcoma-like differentiation. Both elements expressed p53, MDM2, and cyclin-dependent kinase 4 (CDK4), but not thyroid-transcription factor 1 (TTF-1). Mutation analysis of KRAS, EGFR, and beta-catenin revealed no mutations. Comparative genomic hybridization detected +1q, +6p, +6q24qter, +8q, +11q12q14, +11q23qter, +12q12q21, +12q24qter, +17q, +20q, -5q14q23, -9p13pter, -13q21q21, and amplifications at 12q14q21, 15q24qter, 20q11q12. CONCLUSION: The observed molecular and cytogenetic findings may provide additional tools for the differential diagnosis of biphasic pulmonary neoplasms. Furthermore, TP53, MDM2, CDK4, and PTPN1 may be involved in tumourigenesis.

Chromosomal imbalances in primary hepatic carcinosarcoma.

Hepatic carcinosarcoma is an infrequent biphasic tumor composed of carcinomatous and sarcomatous elements, harboring an unfavorable prognosis. The developmental origin of both tumor components and possible molecular genetic mechanisms involved in tumorigenesis are still unclear. We report here a case of hepatic carcinosarcoma in a 76-year-old patient. The tumor was surgically resected and examined histopathologically including immunohistochemical staining. Focal hepatocellular differentiation was detected in the carcinomatous components but also in the pleomorphic undifferentiated spindle cells. Comparative genomic hybridization revealed amp 1q, -4q, -5p14pter, -5q13q31, +6p, -6q, -8p12pter, -12p, -13q12q14, -14q in the carcinomatous components, and +6p, -10q25qter, -22q in the sarcomatous components. The common +6p harbors the serum response factor gene encoding a transcription factor involved in cell proliferation, migration, and differentiation, confirmed by immunostaining. Hepatic carcinosarcoma is a tumor with biphasic morphology but possible monoclonal origin, showing advanced tumor progression in the carcinomatous areas.

Pleural malakoplakia caused by Rhodococcus equi infection in a patient after stem cell transplantation.

Malakoplakia is a disease especially of the urinary tract with typical plaques most frequently observed in the urinary bladder's mucosa. In the context of immunosuppression malakoplakia can also occur in other organs. Some of these extravesical malakoplakias are associated with an infection by Rhodococcus equi, a rare human pathogen well known from veterinary medicine. Here we present the first case of a pleural malakoplakia without lung involvement caused by a proved Rhodococcus equi infection.

Amyloid precursor protein is a biomarker for transformed human pluripotent stem cells.

Increasing evidence suggests an important function of the ß-amyloid precursor protein (APP) in malignant disease in humans; however, the biological basis for this evidence is not well understood at present. To understand the role of APP in transformed pluripotent stem cells, we studied its expression levels in human testicular germ cell tumors using patient tissues, model cell lines, and an established xenograft mouse model. In the present study, we demonstrate the cooperative expression of APP with prominent pluripotency-related genes such as Sox2, NANOG, and POU5F1 (Oct3/4). The closest homologue family member, APLP2, showed no correlation to these stem cell factors. In addition, treatment with histone deacetylase (HDAC) inhibitors suppressed the levels of APP and stem cell markers. Loss of pluripotency, either spontaneously or as a consequence of treatment with an HDAC inhibitor, was accompanied by decreased APP protein levels both in vitro and in vivo. These observations suggest that APP represents a novel and specific biomarker in human transformed pluripotent stem cells that can be selectively modulated by HDAC inhibitors.

A TNF-regulated recombinatorial macrophage immune receptor implicated in granuloma formation in tuberculosis.

Macrophages play a central role in host defense against mycobacterial infection and anti- TNF therapy is associated with granuloma disorganization and reactivation of tuberculosis in humans. Here, we provide evidence for the presence of a T cell receptor (TCR) αß based recombinatorial immune receptor in subpopulations of human and mouse monocytes and macrophages. In vitro, we find that the macrophage-TCRαß induces the release of CCL2 and modulates phagocytosis. TNF blockade suppresses macrophage-TCRαß expression. Infection of macrophages from healthy individuals with mycobacteria triggers formation of clusters that express restricted TCR Vß repertoires. In vivo, TCRαß bearing macrophages abundantly accumulate at the inner host-pathogen contact zone of caseous granulomas from patients with lung tuberculosis. In chimeric mouse models, deletion of the variable macrophage-TCRαß or TNF is associated with structurally compromised granulomas of pulmonary tuberculosis even in the presence of intact T cells. These results uncover a TNF-regulated recombinatorial immune receptor in monocytes/macrophages and demonstrate its implication in granuloma formation in tuberculosis.

Antitumoral effects of calcitriol in basal cell carcinomas involve inhibition of hedgehog signaling and induction of vitamin D receptor signaling and differentiation.

Activation of the Hedgehog (Hh)-signaling pathway due to deficiency in the Hh receptor Patched1 (Ptch) is the pivotal defect leading to formation of basal cell carcinoma (BCC). Recent reports provided evidence of Ptch-dependent secretion of vitamin D(3)-related compound, which functions as an endogenous inhibitor of Hh signaling by repressing the activity of the signal transduction partner of Ptch, Smoothened (Smo). This suggests that Ptch-deficient tumor cells are devoid of this substance, which in turn results in activation of Hh-signaling. Here, we show that the application of the physiologically active form of vitamin D(3), calcitriol, inhibits proliferation and growth of BCC of Ptch mutant mice in vitro and in vivo. This is accompanied by the activation of the vitamin D receptor (Vdr) and induction of BCC differentiation. In addition, calcitriol inhibits Hh signaling at the level of Smo in a Vdr-independent manner. The concomitant antiproliferative effects on BCC growth are stronger than those of the Hh-specific inhibitor cyclopamine, even though the latter more efficiently inhibits Hh signaling. Taken together, we show that exogenous supply of calcitriol controls the activity of 2 independent pathways, Hh and Vdr signaling, which are relevant to tumorigenesis and tumor treatment. These data suggest that calcitriol could be a therapeutic option in the treatment of BCC, the most common tumor in humans.