Prevalence of Microsatellite Instability in Intraductal Papillary Mucinous Neoplasms of the Pancreas.

Microsatellite instability (MSI) caused by mismatch repair deficiency (dMMR) is detected in a small proportion of pancreatic ductal adenocarcinomas (PDACs). dMMR and MSI have been associated with responses of metastatic tumors, including PDACs, to immune checkpoint inhibitor therapy. We performed immunohistochemical analyses of a 445 PDAC specimens, collected from consecutive patients at multiple centers, to identify those with dMMR, based on loss of mismatch repair proteins MLH1, MSH2, MSH6, and/or PMS2. We detected dMMR in 1.6% of tumor samples; we found dMMR in a larger proportion of intraductal papillary mucinous neoplasms-related tumors (4/58, 6.9%) than non- intraductal papillary mucinous neoplasms PDAC (5/385, 1.3%) (P = .02). PDACs with dMMR contained potentially immunogenic mutations because of MSI in coding repeat sequences. PDACs with dMMR or MSI had a higher density of CD8+ T cells at the invasive front than PDACs without dMMR or MSI (P = .08; Fisher exact test). A higher proportion of PDACs with dMMR or MSI expressed the CD274 molecule (PD-L1, 8/9) than PDACs without dMMR or MSI (4/10) (P = .05). Times of disease-free survival and overall survival did not differ significantly between patients with PDACs with dMMR or MSI vs without dMMR or MSI. Studies are needed to determine whether these features of PDACs with dMMR or MSI might serve as prognostic factors.

Testicular histological and immunohistochemical aspects in a post-pubertal patient with 5 alpha-reductase type 2 deficiency: case report and review of the literature in a perspective of evaluation of potential fertility of these patients.

BACKGROUND: Testicular morphology and immunohistochemical studies have never been reported in genetically documented adult patients with 5 alpha-reductase type 2 deficiency (5α-R2 deficiency). CASE PRESENTATION: We describe the testicular histopathology of a 17-year-old XY subject with 5α-R2 deficiency caused by the recurrent homozygous Gly115Asp loss of function mutation of the SRD5A2 gene.We also performed an immunohistochemical analysis in order to further study the relationship between seminiferous tubules structure, Sertoli cell differentiation and androgenic signaling impairment in this case. We thus evaluated the testicular expression of the anti-Müllerian hormone (AMH), androgen receptor (AR) and 3ß-hydroxysteroid dehydrogenase (3ßHSD). Histological analysis revealed a heterogeneous aspect with a majority (92%) of seminiferous tubules (ST) presenting a mature aspect but containing only Sertoli cells and devoid of germ cells and spermatogenesis. Focal areas of immature ST (8%) were also found. Testicular AR and 3ßHSD expression were detected in adult male control, 5α-R2 deficiency and CAIS subjects. However, AMH expression was heterogeneous (detectable only in few AR negative prepubertal ST, but otherwise repressed) in the 5α-R2 deficiency, conversely to normal adult testis in which AMH was uniformly repressed and to an adult CAIS testis in which AMH was uniformly and strongly expressed. CONCLUSION: Intratesticular testosterone can repress AMH by itself, independently of its metabolism into dihydrotestosterone. We also compare our results to the few post pubertal cases of 5α-R2 deficiency with available histological testicular description, reported in the literature. We will discuss these histological findings, in the more general context of evaluating the fertility potential of these patients if they were raised as males and were azoospermic.

Differential mutation profiles and similar intronic TP53 polymorphisms in asbestos-related lung cancer and pleural mesothelioma.

Given the interest in defining biomarkers of asbestos exposure and to provide insights into asbestos-related and cell-specific mechanisms of neoplasia, the identification of gene alterations in asbestos-related cancers can help to a better understanding of exposure risk. To understand the aetiology of asbestos-induced malignancies and to increase our knowledge of mesothelial carcinogenesis, we compared genetic alterations in relevant cancer genes between lung cancer, induced by asbestos and tobacco smoke, and malignant pleural mesothelioma (MPM), a cancer related to asbestos, but not to tobacco smoke. TP53, KRAS, EGFR and NF2 gene alteration analyses were performed in 100 non-small cell lung cancer (NSCLC) patients, 50 asbestos-exposed and 50 unexposed patients, matched for age, gender, histology and smoking habits. Detailed assessment of asbestos exposure was based on both specific questionnaires and asbestos body quantification in lung tissue. Genetic analyses were also performed in 34 MPM patients. TP53, EGFR and KRAS mutations were found in NSCLC with no link with asbestos exposure. NF2 was only altered in MPM. Significant enhancement of TP53 G:C to T:A transversions was found in NSCLC from asbestos-exposed patients when compared with unexposed patients (P = 0.037). Interestingly, TP53 polymorphisms in intron 7 (rs12947788 and rs12951053) were more frequently identified in asbestos-exposed NSCLC (P = 0.046) and MPM patients than in unexposed patients (P < 0.001 and P = 0.012, respectively). These results emphasise distinct genetic alterations between asbestos-related thoracic tumours, but identify common potential susceptibility factors, i.e. single nucleotide polymorphisms in intron 7 of TP53. While genetic changes in NSCLC are dominated by the effects of tobacco smoke, the increase of transversions in TP53 gene is consistent with a synergistic effect of asbestos. These results may help to define cell-dependent mechanisms of action of asbestos and identify susceptibility factors to asbestos.

IL4I1: an inhibitor of the CD8⁺ antitumor T-cell response in vivo.

The L-phenylalanine oxidase IL4I1 inhibits T-cell proliferation in vitro through H(2) O(2) production, and is highly expressed in tumor-associated macrophages. IL4I1 is also detected by immunohistochemistry in neoplastic cells from several B-cell lymphomas and some non-lymphoid tumors. To evaluate IL4I1's effect on tumor growth, we developed a mouse melanoma model constitutively coexpressing IL4I1 and the GP33 epitope. After GP33 vaccination, tumors developed more frequently in mice injected with IL4I1-expressing cells in comparison with mice receiving control cells. Tumor escape was preceded by a rapid diminution of IFN-γ-producing cytotoxic antitumor CD8(+) T cells. Moreover, tumor incidence was already increased when only 20% of the injected cells expressed IL4I1. The minimal IL4I1 activities leading to tumor escape were close to those detected in human melanoma and mesothelioma. Thus, we demonstrate the immunosuppressive functions of IL4I1 in vivo and suggest that IL4I1 facilitates human tumor growth by inhibiting the CD8(+) antitumor T-cell response.

Coexistence of adrenergic and cholinergic nerves in the inferior hypogastric plexus: anatomical and immunohistochemical study with 3D reconstruction in human male fetus.

Classic anatomical methods have failed to determine the precise location, origin and nature of nerve fibres in the inferior hypogastric plexus (IHP). The purpose of this study was to identify the location and nature (adrenergic and/or cholinergic) of IHP nerve fibres and to provide a three-dimensional (3D) representation of pelvic nerves and their relationship to other anatomical structures. Serial transverse sections of the pelvic portion of two human male fetuses (16 and 17 weeks' gestation) were studied histologically and immunohistochemically, digitized and reconstructed three-dimensionally. 3D reconstruction allowed a 'computer-assisted dissection', identifying the precise location and distribution of the pelvic nerve elements. Proximal (supra-levator) and distal (infra-levator) communications between the pudendal nerve and IHP were observed. By determining the nature of the nerve fibres using immunostaining, we were able to demonstrate that the hypogastric nerves and pelvic splanchnic nerves, which are classically considered purely sympathetic and parasympathetic, respectively, contain both adrenergic and cholinergic nerve fibres. The pelvic autonomic nervous system is more complex than previously thought, as adrenergic and cholinergic fibres were found to co-exist in both 'sympathetic' and 'parasympathetic' nerves. This study is the first step to a 3D cartography of neurotransmitter distribution which could help in the selection of molecules to be used in the treatment of incontinence, erectile dysfunction and ejaculatory disorders.

Incidence of inflammatory breast cancer in patients with clinical inflammatory breast symptoms.

BACKGROUND: To describe a large cohort of women with non-puerperal inflammatory breast and to identify characteristics of inflammatory breast cancer. METHODS: All patients consulting for inflammatory breast syndrome in the breast unit of our tertiary University hospital between September 2013 and December 2015 were prospectively included. We excluded women who were pregnant or in the postpartum period. Patients underwent systematic clinical examination and imaging (breast ultrasonography and mammography). A biopsy was performed if the clinician suspected a malignant lesion of the breast. Clinicopathologic and radiologic data were registered. Statistics were performed using R (3.0.2 version) software. RESULTS: Among the 76 patients screened and included, 38 (50%) had a malignant lesion at final diagnosis, 21 (27.6%) were diagnosed with infectious disease and 17 (22.4%) with inflammatory disease of the breast. When compared to patients with benign disease, patients with a malignant lesion were significantly older (p = 0.022, CI95% 1.78-14.7), had a significantly bigger palpable mass (p<0.001, CI 95% 22.8-58.9), were more likely to have skin thickening (p = 0.05) and had more suspicious lymph nodes at clinical examination (p<0.001, CI 95% 2.72-65.3). Precise limits on ultrasonography were significantly associated with benign lesions. The presence of a mass (p = 0.04), micro calcifications (p = 0.04) or of focal asymmetry (p<0.001, CI95% 1.3-618) on mammography was significantly associated with malignant disease. CONCLUSION: Inflammatory breast cancer was common in our cohort of women consulting for inflammatory breast syndrome. Identifying these patients with high-risk malignancy is crucial in the management of an inflammatory breast.

[Chronic abdominal pain due to bowel ischemia in a patient with Leiden factor V mutation]. / Douleurs abdominales chroniques par ischémie mésentérique liée à une mutation du facteur V Leiden.

Leiden Factor V mutation, associated with resistance to activated protein C, is a prothrombotic state found in 20% of the patients with a first episode of deep-vein thrombosis. We report the case of a 30-Year-old woman with a history of intermittent abdominal pain who developed small bowel infarction requiring extensive small bowel resection. Biological search for prothrombotic disorder showed resistance to activated protein C due to homozygosity for the factor V Leiden mutation. Long-term anticoagulant therapy was initiated. Unexplained abdominal pain may be due to venous mesenteric ischemia, which can be associated with factor V Leiden mutation.

[Nasal NK/T lymphoma. A case report]. / Lymphome NK/T nasal. A propos d'un cas.

We report a case of nasal NK/T lymphoma occurring in a 42 year old man, after a 2 year history of nasal obstruction initially related to chronic sinusitis. A first superficial biopsy was not contributive. Twenty months later, a second nasal biopsy led to the diagnosis of nasal NK/T cell lymphoma in view of the presence of a pleomorphic lymphoid infiltrate associated with necrosis and angiocentric features. Extensive immunohistochemical studies performed on paraffin and frozen sections together with genotypic analysis supported the NK cell origin of the neoplastic cells. In addition, EBV infection was established by in situ hybridization which showed EBERs transcripts in the nuclei of virtually all neoplastic cells. The tumour rapidly progressed and the patient died six months after diagnosis.

Oncogene abnormalities in a series of primary melanomas of the sinonasal tract: NRAS mutations and cyclin D1 amplification are more frequent than KIT or BRAF mutations.

Primary malignant melanoma of sinonasal tract is a rare but severe form of melanoma. We retrospectively analyzed 17 cases and focused on the histologic presentation and the expression of c-Kit, epidermal growth factor receptor (EGFR), cyclin D1/Bcl-1, PS100, and HMB45 and searched for BRAF, NRAS, and KIT mutations that are known to be associated with melanoma subtypes, together with amplifications of KIT, cyclin D1, cyclin-dependent kinase 4, MDM2, and microphthalmia-associated transcription factor using quantitative polymerase chain reaction. In most cases (78%), an in situ component was evidenced. Invasive components were composed of diffuse areas of rhabdoid, epithelioid, or spindle cells and, in most cases, lacked inflammatory reaction, suggesting that an immune escape phenomenon probably develops when the disease progresses. EGFR was rarely and weakly expressed in the in situ component of 2 cases. None of the investigated case showed BRAF V600E, but 1 had a D594G mutation. NRAS mutations in exon 2 (G12D or G12A) were found in 3 cases (18%), and a KIT mutation in exon 11 (L576P), in 1, whereas c-Kit was expressed at the protein level in half of the cases. Amplifications of cyclin D1 were evidenced in 5 cases, confirmed in 3 by fluorescence in situ hybridization, but this was not always correlated with protein expression, found in 8 patients (62.5%), 3 having no significant amplification. In conclusion, primary malignant melanoma of sinonasal tract is not associated with BRAF V600E mutations. Instead, NRAS or KIT mutations and cyclin D1 amplification can be found in a proportion of cases, suggesting that primary malignant melanoma of sinonasal tract is heterogeneous at the molecular level and should not be sensitive to therapeutic approaches aiming at BRAF.

p16INK4A inactivation mechanisms in non-small-cell lung cancer patients occupationally exposed to asbestos.

Epidemiological studies have shown that asbestos fibers constitute the major occupational risk factor and that asbestos acts synergistically with tobacco smoking to induce lung cancer. Although some somatic gene alterations in lung cancer have been linked to tobacco smoke, few data are available on the role of asbestos fibers. P16/CDKN2A is an important tumor suppressor gene that is frequently altered in lung cancer via promoter 5'-CpG island hypermethylation and homozygous deletion, and rarely via point mutation. Many studies suggest that tobacco smoking produces P16/CDKN2A promoter hypermethylation in lung cancer, but the status of this gene in relation to asbestos exposure has yet to be determined. The purpose of this study was to investigate the mechanism of P16/CDKN2A alterations in lung cancer in asbestos-exposed patients. P16/CDKN2A gene status was studied in 75 human non-small-cell lung cancer (NSCLC) cases with well-defined smoking habits, and detailed assessment of asbestos exposure, based on occupational questionnaire and determination of asbestos bodies in lung tissue. The results of this study confirm published data on the effect of tobacco smoke on P16/CDKN2A gene alterations, characterized by significantly higher P16/CDKN2A promoter hypermethylation in heavy smokers (more than 40 pack-years (P-Y)) than in smokers of less than 40 P-Y. These results also demonstrate a higher incidence of loss of heterozygosity and homozygous deletion in asbestos-exposed cases, after adjustment for age and cumulative tobacco consumption, than in unexposed cases (P=0.0062). This study suggests that P16/CDKN2A gene inactivation in asbestos-exposed NSCLC cases mainly occurs via deletion, a feature also found in malignant mesothelioma, a tumor independent of tobacco smoking but associated with asbestos exposure, suggesting a possible relationship with an effect of asbestos fibers.

Innervation of the female human urethral sphincter: 3D reconstruction of immunohistochemical studies in the fetus.

OBJECTIVES: The precise location, origin and nature of nerve fibers innervating the urethral sphincter have not been clearly established. Classical anatomical studies based on cadaver dissections have provided conflicting results concerning the location of pudendal and autonomic nerve fibers. This study was designed to identify nerve fibers innervating the urethral sphincter and to provide a three-dimensional representation of their tissue relations in the female human fetus. MATERIALS AND METHODS: Histology and immunohistochemistry (Masson's Trichromic, Luxol Fast Blue, Protein S 100 immunostaining and smooth fiber actin immunostaining) were performed on the external urethral sphincter of ten female fetuses with a crown-rump length of 112 to 340mm. Three-dimensional reconstructions of the urethral structure and innervation were obtained from serial sections using Surf Driver 3.5.3 software (David Moody and Scott Lozanoff). RESULTS: Three-dimensional reconstructions of the same sections with different stains demonstrated the precise structure of the muscle layers (smooth and striated muscle fibers) and nerve fibers (myelinated and unmyelinated) and their relations with the urethra and vaginal wall. The proximal third consisted of a circular smooth muscle sphincter, the middle third consisted of two circular layers of smooth and striated muscle fibers and the distal third consisted of a circular layer of smooth muscle fibers surrounded by an omega-shaped layer of striated muscle fibers. In the proximal third of the urethral sphincter, myelinated fibers were identified running with unmyelinated fibers from the pelvic plexus. These fibers were closely related to the lateral and anterior aspects of the vagina. Unmyelinated fibers entered the smooth muscle part of the sphincter at 4 o'clock and at 8 o'clock. Most myelinated fibers entered the sphincter at 3 o'clock and at 9 o'clock. CONCLUSION: Histological and immunohistochemical three-dimensional reconstruction of the anatomical structures of the urethral sphincter provides a better understanding of the origin and nature of the Innervation participating in urinary continence. It provides a very informative view of the three-dimensional arrangement of sphincter muscle layers.

The precise location and nature of the nerves to the male human urethra: histological and immunohistochemical studies with three-dimensional reconstruction.

OBJECTIVES: The precise location, origin and nature of nerve fibers innervating the male urethral sphincter have not been clearly established. Classical anatomical studies based on cadaver dissections have provided conflicting results concerning the location of somatic and autonomic nerve fibers. This study was designed to identify nerve fibers innervating the male urethral sphincter and to provide a three-dimensional representation of their tissue relations in the human male fetus. MATERIALS AND METHODS: Histology and immunohistochemistry (Hematein-Eosin-Safran, Luxol Fast Blue, Protein S 100 immunolabeling and smooth fibers actin immunolabeling) were performed in male external urethral sphincter of ten male fetuses (114-342 mm crown-rump length). Three-dimensional reconstruction of the urethral structure and innervation were obtained from serial sections using Surf Driver 3.5.3 software. RESULTS: The three-dimensional reconstruction of the same section levels with different strains allowed to identify the precise structure of the muscular layers and the nature of nervous elements (myelinated and unmyelinated), their distributions and their relations with the urethral wall, the prostate and the seminal vesicles. CONCLUSION: Histological and immunohistochemical three-dimensional reconstruction of the nervous elements of the urethral sphincter gives a very didactical understanding of the three dimensional arrangement of the urethral nerves and their relationships with the urethral layers. It allows a better understanding of the origin, the course and the nature of the nervous elements participating in the urinary continence.

Low-grade steatosis and major changes in portal flow as new prognostic factors in steroid-treated alcoholic hepatitis.

The aim of this study was to assess the prevalence and prognostic value of major alterations of portal flow in patients with steroid-treated alcoholic hepatitis. Fifty patients with severe, histologically proven alcoholic hepatitis were enrolled. Clinical data, liver test results, and hepatic Doppler ultrasound findings were collected at inclusion and at month 2. Patients were followed for 1 year or until death. Major changes in portal flow were defined as reversed or alternating flow in the portal trunk and/or in intrahepatic portal branches. Changes in portal flow were observed in 24 (48.0%) of 50 and 17 (39.5%) of 43 patients at inclusion and month 2, respectively. Univariate analysis showed that age older than 50 years, steatosis less than 20% on initial liver biopsy, presence of major changes in portal flow, Child-Turcotte-Pugh score higher than 12, factor V level higher than 45%, and hepatofugal splenic blood flow were associated with a lower 1-year survival. Cox regression analysis showed that steatosis < 20% (relative hazard [RH] = 9.3, P = .0009) and major changes in portal flow (RH = 3.1, P = .04), were independently associated with poor survival. In conclusion, major changes in portal flow are frequent in patients with severe alcoholic hepatitis. Altered portal flow and steatosis < 20% are new prognostic factors in steroid-treated alcoholic hepatitis and must be taken into account in patient management.

Gelatinase activities in the airways of premature infants and development of bronchopulmonary dysplasia.

Matrix-degrading metalloproteinases may play a role in the pathophysiology of bronchopulmonary dysplasia (BDP). We, therefore, evaluated correlations between gelatinase activities [metalloproteinase (MMP)-2 and MMP-9] or tissue inhibitor of metalloproteinase (TIMP)-1 levels present in the airways during the initial phase of hyaline membrane disease and the onset of BPD. Tracheal aspirates were obtained within 6 h of birth (day 0) from 64 intubated neonates with a gestational age < or =30 wk. Forty-five neonates were resampled on day 3 or 5. Total MMP-2 level measured by zymography fell with time, whereas total MMP-9 level and TIMP-1 levels, assayed by ELISA, increased; the MMP-9 increase correlated with the increase in airway inflammatory cell numbers. Among the parameters measured on day 0, 3, or 5, lower total MMP-2 level, lower birth weight, and higher fraction of inspired oxygen on day 0 were significantly and independently associated with the development of BPD. In conclusion, MMP-9 level and TIMP-1 levels increased after birth but are not linked to BPD outcome. In contrast, low MMP-2 level at birth is strongly associated with the development of BPD.