Distinct clonal evolution in a case with anaplastic embryonal rhabdomyosarcoma.

BACKGROUND: Clonal evolution of malignancy is a complex process related to intratumoral heterogeneity, as recent studies have also demonstrated in rhabdomyosarcoma. The purpose of this study is to present a distinct clonal feature of a case with anaplastic embryonal type rhabdomyosarcoma (ERMS) using molecular analysis. METHODS: A five-year-old girl developed a metastatic pelvic tumor. We cultured neoplastic cells isolated from the biopsy sample. Next, to characterize the current case, we analyzed the biopsy sample, autopsy sample, and established cell line using combined modalities, including histopathological, cytogenetic, and molecular assay. We also undertook the backtrack mutation-specific polymerase chain reaction to reveal clonal composition. RESULTS: The histology of the biopsy sample was consistent with ERMS with focal anaplasia. We established a permanently growing cell line, ICH-ERMS-1, from the biopsy sample. On molecular analysis, the biopsied tissue revealed a missense mutation at codon 245 of TP53. In contrast, the autopsy tumor tissue and the cell line established from the biopsied tissue showed a missense mutation at codon 248. A backtrack study using mutation-specific polymerase chain reaction detected a TP53 codon 248 mutation in the original biopsy sample. All the specimens examined had a missense mutation at PTPN11 codon 69. CONCLUSIONS: This study highlights intratumoral heterogeneity and distinct clonal change related to the functional context in our anaplastic ERMS case, supporting the concept of intratumoral heterogeneity and clonal evolution. It requires further case collection to reveal whether p14ARF-p53-MDM2 tumor suppressor pathway alteration, considered a late event in ERMS tumorigenesis, is responsible for anaplasia in ERMS.

Histological Comparison of Cold versus Hot Snare Resections of the Colorectal Mucosa.

BACKGROUND: Delayed postpolypectomy bleeding occurs more frequently after hot resection than after cold resection. OBJECTIVE: To elucidate the underlying mechanism, we performed a histological comparison of tissue after cold and hot snare resections. DESIGN: This is a prospective study, registered in the University Hospital Medical Information Network (UMIN000020104). SETTING: This study was conducted at Aizu Medical Center, Fukushima Medical University, Japan. PATIENTS: Fifteen patients scheduled to undergo resection of colorectal cancer were enrolled. INTERVENTION: On the day before surgery, 2 mucosal resections (hot and cold) of normal mucosa were performed on each patient using the same snare without saline injection. The difference was only the application of electrocautery or not. Resection sites were placed close to the cancer to be included in the surgical specimen. MAIN OUTCOME MEASURES: The primary outcome measure was the depth of destruction. Secondary outcome measures included the width of destruction, depth of the remaining submucosa, and number of vessels remaining at the resection sites. The number and diameter of vessels in undamaged submucosa were also evaluated. RESULTS: All cold resections were limited to the shallow submucosa, whereas 60% of hot resections advanced to the deep submucosa and 20% to the muscularis propria (p < 0.001). There was no significant difference in the width of destruction. The number of remaining large vessels after hot resections trended toward fewer (p = 0.15) with a decreased depth of remaining submucosa (p = 0.007). In the deep submucosa, the vessel diameter was larger (p < 0.001) and the number of large vessels was greater (p = 0.018). LIMITATIONS: Histological assessment was not blinded to the 2 reviewers. Normal mucosa was used instead of adenomatous tissue. CONCLUSIONS: Hot resection caused damage to deeper layers involving more large vessels. This may explain the mechanism for the reduced incidence of hemorrhage after cold snare polypectomy. See Video Abstract at http://links.lww.com/DCR/A631.

Lectin inhibits antigen-antibody reaction in a glycoform-specific manner: Application for detecting α2,6sialylated-carcinoembryonic antigen.

Carcinoembryonic antigen (CEA) is a glycoprotein marker, which is widely used for diagnosing various cancers, especially colon adenocarcinoma. In addition, CEA mediates homotypic adhesion of colon adenocarcinoma cells, which appears to favor hematogenous metastasis. CEA carries α2,6sialyl residues on its N-glycans whereas a normal counterpart, normal fecal antigen-2, does α2,3sialyl residues, suggesting that cancer-specific  α2,6sialylation on CEA may play a role for cell invasion and metastasis. A simple and rapid estimation of α2,6sialyled CEA in detergent extracts from formalin-fixed colon adenocarcinoma by "lectin inhibition" is reported. In the lectin inhibition method, Sambucus sieboldiana Agglutinin (SSA) lectin, an α2,6sialic acid binder, was used as a glycoform-specific inhibitor for antigen-antibody reaction in ELISA. Detergent extracts from colon adenocarcinoma showed a fair amount of ELISA signal in the absence of SSA whereas the signal was markedly reduced (45≈74%) in the presence of SSA, suggesting that the extracts contains α2,6sialyled CEA. The presence of α2,6sialyled CEA in the extracts was confirmed by lectin microarray, in which SSA, Sambucus nigra agglutinin, and Trichosanthes japonica agglutinin I lectins were used as α2,6sialyl binders. Thus lectin inhibition is a simple and rapid method for detecting α2,6sialyled CEA even in crude detergent extracts from formalin-fixed adenocarcinoma tissue.

Secondary neuroendocrine tumor after allogeneic bone marrow transplantation.

Here we report a case of aggressive neuroendocrine tumor (NET), which is an extremely rare secondary solid tumor that occurs after allogeneic hematopoietic cell transplantation (allo-HSCT). A patient with chronic active Epstein-Barr virus infection received allo-HSCT from an HLA-DR two allele-mismatched unrelated donor. Four years later, he developed NET with multiple metastases. He received thoraco-abdominal irradiation as a conditioning regimen, and developed repeated episodes of intestinal graft-versus-host disease, for which he received long-term immunosuppressive therapy. Although these factors may be potential contributing factors to the development of secondary NET, the exact pathogenesis remains unclear.

Multiple recurrent sinus of valsalva aneurysms.

We report a case of multiple unruptured sinus of Valsalva aneurysms in an adult patient over nine years.

Intraosseous spindle cell hemangioma of the calcaneus: a case report and review of the literature.

Spindle cell hemangioma, a rare benign tumor characterized by cavernous blood vessels and spindled areas, typically arises in the subcutis of the distal extremities, particularly the hand. The case of intraosseous spindle cell hemangioma is extremely rare, and only 1 case arises in the frontal bone has been reported previously. We describe herein a case of intraosseous spindle cell hemangioma occurring in the left calcaneus in a 65-year-old woman. The patient was successfully treated by the operation. The present case is instructive especially in the differential diagnosis of primary bone tumor structured by spindle cells, for which the possibility of spindle cell hemangioma should be considered.

Immunolocalization of CD80 and CD86 in Non-Small Cell Lung Carcinoma: CD80 as a Potent Prognostic Factor.

It has been demonstrated that tumor cells express programed cell death protein 1 (PD-L1) to escape T lymphocytes that express programed cell protein 1 (PD-1), and PD-1/PD-L1 immune checkpoint inhibitors have been regarded in lung cancer patients. CD80 and CD86 are members of B7 superfamily which regulates T lymphocyte activation and tolerance. However, immunolocalization of CD80 and CD86 has not been examined in the lung carcinoma tissues and their clinical significance remains unknown. Therefore, to clarify clinical significance of CD80 and CD86, we immunolocalized these in 75 non-small cell lung carcinomas (NSCLC) in this study. Immunoreactivities of CD80 and CD86 were mainly detected in tumor-infiltrating macrophages. Immunohistochemical CD80 status was high in 56% of NSCLC, and it was positively associated with stage, pathological T factor, distant metastasis, histological type and PD-L1 status. Moreover, multivariate analysis turned out that the CD80 status was an independent worse prognostic factor. CD86 status was high in 53% of the cases, but it was not significantly associated with any clinicopathological parameters. These findings suggest that CD80 is a potent worse prognostic factor possibly in association with escape from immune attack in NSCLC.

MTX-HOPE is a low-dose salvage chemotherapy for aged patients with relapsed or refractory non-Hodgkin lymphoma.

As the aging society advances, the number of non-Hodgkin lymphoma (NHL) patients is increasing. Aged relapsed or refractory (r/r) NHL patients have limited treatment options. Therefore, a safe and effective regimen is urgently needed for these patients. Thus, we originally developed the MTX-HOPE (methotrexate, hydrocortisone, vincristine, sobuzoxane, and etoposide) regimen for r/r NHL and validated the safety and efficacy of this regimen in a clinical setting. We analyzed the data of 42 r/r NHL patients who received MTX-HOPE in this single-center retrospective cohort study. The median age of the patients was 81 years. The overall response rate was 45.3%. The median overall survival (OS) was 7 months, the one-year OS was 43.7%, and the two-year OS was 40.8%. Grade ≥3 neutropenia and renal dysfunction were observed in 47.6% and 11.9% of patients, respectively, and treatment-related death were not observed. Appropriate supportive care enabled these patients to continue the MTX-HOPE regimen. The proportion of patients who needed hospitalization during MTX-HOPE therapy was only 21.4%. Multivariable analyses with the Cox proportional hazards model revealed that both OS and progression-free survival (PFS) were significantly influenced by high Ki-67 expression in pathology, with response to the MTX-HOPE regimen after three to five cycles as a time-dependent covariate. Our results suggest that MTX-HOPE therapy can be an option for non-aggressive r/r NHL patients. To validate MTX-HOPE therapy, further prospective investigation is needed.

Pathological Complete Response after Immune-Checkpoint Inhibitor Followed by Salvage Surgery for Clinical Stage IV Pulmonary Adenocarcinoma with Continuous Low Neutrophil-to-Lymphocyte Ratio: A Case Report.

Immune-checkpoint inhibitors (ICIs) play a crucial role in the treatment of advanced nonsmall cell lung cancer (NSCLC); however, most patients fail this treatment after a limited period. We here report a patient with a pathological complete response after treatment with ICI for stage IV pulmonary adenocarcinoma. A 73-year-old man was referred to our hospital because of hoarseness. A roentgenogram and chest CT scan revealed a huge (78-mm diameter) pulmonary tumor in the right upper lobe and a tumor with cavitation in the left lower lobe. A CT scan also showed enlarged upper mediastinal lymph nodes (LNs). Transbronchial lung biopsy of the tumors showed adenocarcinomas in both. The tumor in the right upper lobe was considered to be the primary with mediastinal LNs metastasis and that in the left lower lobe a pulmonary metastasis. The disease was determined to be cT4N2M1a stage IVA. He was treated with first-line chemotherapy comprising cisplatin, pemetrexed, and bevacizumab for 6 cycles. However, 6 months after initial treatment, the primary and metastatic tumors enlarged, and he was treated with second-line anti-programed death 1 therapy for 7 months with a partial response. 18-fluorodeoxyglucose positron emission tomography (FDG-PET) revealed weak accumulation of FDG in the primary tumor only with no accumulation in the left pulmonary metastasis or mediastinal lymph node (LNs), despite the LNs still being enlarged. He was diagnosed as having ycT1bN0M0 stage IA2 disease and underwent right upper lobectomy. Postoperative pathological findings revealed that cancer tissues had been replaced by scar tissue and that CD4-positive T cells, rather than CD8-positive T cells, were predominant. It was also noted that he had a lower neutrophil-to-lymphocyte ratio (NLR) during immunotherapy than before immunotherapy and after surgery. He was diagnosed to be ypT0N0M0 stage 0 (Ef.3). His postoperative course was uneventful, and he remained well for 12 months after surgery with no further treatment. Neoadjuvant chemotherapy with ICIs for advanced NSCLC may be a promising modality, even for clinical stage IV disease, in the near future. Furthermore, NLR during immunotherapy may be a promising biomarker of ICIs treatment.

Femoral marrow MRI is a non-invasive, non-irradiated and useful tool for detecting bone marrow involvement in non-Hodgkin lymphoma.

Femoral marrow magnetic resonance imaging (MRI) is a non-invasive, non-irradiated and useful modality for evaluating bone marrow (BM) conditions. Human adult femoral BM is almost uniformly fatty marrow and has the largest volume of a single bone. MRI has an extremely high resolution for fat and water, which allows high-contrast imaging of cellular infiltration into fat tissue. In hematological diseases, femoral BM MRI can clearly detect cell infiltration, which is symmetrically imaged from the proximal to the distal direction of abnormal signal areas. Thus, we investigated the significance of femoral MRI for non-Hodgkin lymphoma (NHL). We analyzed the data of 69 NHL patients who received femoral MRI at diagnosis in this single-center retrospective cohort study. The median patient age was 73 years. MRI patterns were mainly classified as uniform patterns or nonuniform patterns. We also classified the range of cellular marrow as high-grade or low-grade based on whether it had spread to over half of the femur. Both overall survival (OS) and progression-free survival (PFS) were significantly influenced by abnormal femoral marrow MRI. In particular, the patients with cellular femoral marrow lesions had a worse OS and PFS based on log-rank tests. Multivariable analyses with the Cox proportional hazards model revealed that OS and PFS were significantly influenced by cellular marrow diagnosed by femoral MRI. We concluded that femoral marrow MRI is a useful tool for detecting BM involvement and an independent prognostic factor in NHL patients.

Identification and metastatic potential of tumor-initiating cells in malignant rhabdoid tumor of the kidney.

PURPOSE: Malignant rhabdoid tumor of the kidney (MRTK) is a rare and highly aggressive malignancy of infanthood. In an effort to delineate MRTK progression, we investigated the metastatic fate of some MRTK cells using xenotransplantation animal models and the tumor-initiating potential of CD133(+) MRTK cells. EXPERIMENTAL DESIGN: We established two MRTK cell lines (JMU-RTK-1 and JMU-RTK-2) from patients with MRTK. We generated five luciferase-expressing MRTK cells for in vivo luminescent imaging and evaluated the metastatic fate in an orthotopic xenotransplantation model. Capacities of MRTK-initiating cells were examined in nonobese diabetic/severe combined immunodeficient mice after antibody-mediated magnetic bead sorting. Use of chemokine receptor CXCR4 expression as a metastatic marker was evaluated by flow cytometry and Western blotting. RESULTS: MRTK cell lines showed distant organ metastasis. JMU-RTK-1, JMU-RTK-2, and G401 cells showed considerable aggressiveness compared with SWT-1 and SWT-2 cells (P < 0.05). Moreover, as few as 1,000 CD133(+) MRTK cells initiated tumor development in nonobese diabetic/severe combined immunodeficient mice by 21 days (60-100%) in all examined cell lines, although the same number of CD133(-) MRTK cells could not form tumors (0%). Interestingly, the metastatic potential of the CD133(+) population remained unaffected compared with a nonenriched population. The potential metastatic marker CXCR4 was expressed in CD133(+) and CD133(-) MRTK cells, and CD133(-) cells seemed to play a cooperative role in terms of tumorigenicity and metastasis. CONCLUSIONS: These results suggest that CD133(+) cells may determine the metastatic fate of MRTK cells and that CD133(-) cells may play an auxiliary role in tumor progression and metastasis.

Successful Multidisciplinary Treatment for Aggressive Primary Pulmonary Undifferentiated Pleomorphic Sarcoma.

Undifferentiated pleomorphic sarcoma (UPS) was previously known as malignant fibrous histiocytoma (MFH). This sarcoma occurs preferentially in the extremities and retroperitoneal space; primary pulmonary UPS/MFH is rare. We report a 52-year-old woman referred to our hospital with dyspnea and severe cough. Chest computed tomography (CT) revealed a pulmonary mass in the left upper lobe and pleural effusion. Cytology of the effusion showed no malignancy; however, the tumor increased rapidly in size, and the patient's respiratory symptoms worsened. The tumor occupied almost all of the left upper lobe and involved the adjacent pericardium. She underwent left upper lobectomy with pericardial resection and reconstruction. Postoperative pathology of the resected specimen showed undifferentiated pulmonary sarcoma, pT4N0M1a stage IV A, and genetic analyses revealed the v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation. The patient's dyspnea recurred 1 month postoperatively, and CT showed marked pleural effusion. An 18F-fluorodeoxyglucose positron emission tomography demonstrated abnormal diffuse accumulation of 18F-fluorodeoxyglucose in the left pleural cavity. We initiated five cycles of chemotherapy with doxorubicin and ifosfamide, and the patient has been well without recurrence for 24 months after multidisciplinary treatment with surgery followed by systemic combination chemotherapy. We successfully treated our patient with primary pulmonary UPS/MFH using a multidisciplinary approach, even though this sarcoma carries a poor prognosis and is insensitive to both chemotherapy and radiotherapy.

Wine cup stoma anastomosis after extended sleeve lobectomy for central-type squamous cell lung cancer.

BACKGROUND: Extended sleeve lobectomy is rarely applied to pulmonary surgery for primary lung cancer to avoid a pneumonectomy. As there is a size discrepancy between main bronchus and peripheral bronchus, ingenuity to improve anastomosis is required in the bronchoplasty. We report herein a case in which successful reconstruction of extended sleeve lobectomy with bronchial wall flap. CASE PRESENTATION: We report on a 64-year-old man suffering from hemoptysis, cough, mild fever and dyspnea. His computed tomography (CT) scan showed solid tumor of 40 mm in diameter in left lower bronchus, which obstructed the lower bronchus and caused obstructive pneumonia of left lower lobe and expanded to second carina and pulmonary artery. His bronchoscopy showed that tumor was exposed in the bronchial lumen and infiltrated to left main bronchus and upper bronchus even though the scope could pass through the exposed tumor of upper bronchus. Transbronchial lung biopsy showed squamous cell carcinoma. He had undergone left sleeve lingular segmentectomy and left lower lobectomy. Reconstruction was performed with bronchial wall flap. Pathological findings revealed pT3N0M0 stage IIB according to UICC 8th edition. Postoperative bronchoscopic findings showed no troubles at the anastomotic site. He has been well for eighteen months without recurrence after surgery. CONCLUSIONS: We experienced a successful case who was reconstructed with bronchial wall flap (wine cup stoma) after extended sleeve lobectomy. This technique might be also useful for other types of extended sleeve lobectomy and lung transplantation to adjust caliber changes of bronchi.

The Feasibility and Histological Diagnostic Accuracy of Novel Menghini Needle (EUS Sonopsy CY™) for Endoscopic Ultrasound-Guided Fine-Needle Aspiration Biopsy of Solid Pancreatic Masses: A Prospective Crossover Study Comparing Standard Biopsy Needles.

BACKGROUND AND OBJECTIVES: Recently, a 21G Menghini-type needle for EUS-guided fine-needle aspiration biopsy (EUS-FNAB) has been developed. The stylet of the EUS Sonopsy CY™ remains inside the needle during aspiration. Therefore, it is expected to obtain higher-quality histological core specimens without crushing the material or blood contamination. The aim of this study is to evaluate the feasibility and diagnostic accuracy of EUS-FNAB of solid pancreatic masses with this new biopsy needle. METHODS: A total of 30 patients with solid pancreatic masses who underwent EUS-FNAB with two different types of needles, EUS Sonopsy™ and ProCore™, were included in a prospective, randomized, controlled, crossover study. All the pancreatic masses were punctured with the two needles and were randomized regarding the order of the needle to be used. The primary outcome was to compare the diagnostic accuracy and the rates of tissue acquisition of the two needles. RESULTS: The tissue acquisition rate was not significantly different between the EUS Sonopsy CY™ needle and the ProCore™ needle (78.6% vs. 82.1%, P = 1.00). The histological diagnostic accuracy was also similar between the two needles (73% vs. 80%, P = .63). There was also no difference regarding the accuracy of cytology alone and the combination of both histological and cytological assessments between the EUS Sonopsy CY™ needle and the ProCore™ needle (90% vs. 87%, P = 1.00 and 90% vs. 90%, P = 1.00, respectively). CONCLUSIONS: EUS Sonopsy CY™ is a reliable device for EUS-FNAB of solid pancreatic masses.

Tumor-associated macrophages correlate with vascular space invasion and myometrial invasion in endometrial carcinoma.

OBJECTIVE: This study was conducted to determine whether tumor-associated macrophages (TAMs) correlate with clinicopathological features in endometrioid adenocarcinoma. METHODS: 76 cases of endometrioid adenocarcinoma treated initially by hysterectomy with pelvic lymphadenectomy were retrospectively retrieved, and their histological features were evaluated. Immunohistochemical staining for CD68, CD34, and Ki-67 was performed on paraffin-embedded sections. TAMs were counted in two areas: in the invasive margin (margin TAMs) and in the tumor (intratumor TAMs). RESULTS: Margin TAMs were significantly associated with FIGO stage (P=0.033), histological grade (P=0.008), myometrial invasion (P=0.0001), pelvic lymph node metastasis (P=0.027), and vascular space invasion (P=0.0001). Intratumor TAMs were significantly associated with intratumor Ki-67 (P=0.006) and microvessel density (P=0.020). Patients with high margin TAMs (> or = 20) had significantly worse progression-free survival (PS) and overall survival (OS) than those with low margin TAMs (< 20) (log rank test, P=0.0031 and P=0.0085, respectively). On multivariate analysis, high margin TAMs were significantly associated with vascular space invasion (P=0.013; HR, 6.05; 95% confidence interval [CI], 1.468-24.938) and myometrial invasion (P=0.041; HR, 4.03; 95% CI, 1.06-14.71). Vascular space invasion was only associated with PFS. CONCLUSION: Although on univariate analysis TAMs are associated with other poor prognosticators, on a multivariate analysis, TAMs appear only to be associated with MI and VI. TAMs may play a significant role in the biology of tumor progression of endometrial adenocarcinoma, but do not appear to be independent prognostic indicators of patient's survival.

Up-regulation of hepatic heme oxygenase-1 expression by locally induced interleukin-6 in rats administered carbon tetrachloride intraperitoneally.

We previously reported that interleukin-6 (IL-6) was locally produced in the early period after intraperitoneal (i.p.) or subcutaneous carbon tetrachloride (CCl4) administration, but not after oral (p.o.) administration. In the present study, we focused on the up-regulation of stress-inducible proteins induced by IL-6 after i.p. CCl4 administration. The expression of heme oxygenase-1 (HO-1) (EC 1.14.99.3) mRNA and protein were induced more in rats administered CCl4 via the i.p. route, compared with the p.o. route; however, expression of heat shock protein (HSP) 72 and HSP90 mRNA were increased to similar extents in both experimental groups. The induction of HO-1 mRNA and protein after i.p. CCl4 administration were significantly reduced after pretreatment with anti-rat IL-6 antibody. Activation of the signal transducer and activator of transcription factor 3 (STAT3), which promotes HO-1 expression, peaked together with plasma levels of IL-6 after i.p. CCl4 administration, suggesting that hepatic HO-1 expression was increased by IL-6 via the Janus kinase/STAT3 pathway. The present data indicate that hepatic HO-1 is up-regulated by endogenously produced IL-6, in addition to its up-regulation by heme derived from cytochrome P450 which has already been reported in rats administered i.p. CCl4. The up-regulation of hepatic HO-1 expression may reduce the tissue injury to livers caused by CCl4.

Lung parenchymal involvement of primary bone marrow follicular lymphoma: a rare case study.

A 76-year-old man presented with shortness of breath. Computed tomography revealed ground-glass opacity and interlobular thickening in the right lower lobe. Blood examination showed elevated levels of white blood cell count and lymphocytes. Bone marrow aspiration revealed low-grade follicular lymphoma. Histopathological examination of the surgical lung biopsy from the right lower lobe demonstrated usual interstitial pneumonia and scattered aggregation of lymphocytes with poorly formed non-necrotizing granuloma. An 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT) did not show intense uptake in areas other than the right lower lobe. We concluded that the granuloma in the lung was presumed to be a sarcoid reaction associated with bone marrow follicular lymphoma, and the intense 18F-FDG uptake in the right lower lobe might have been due to a sarcoid reaction. Immunohistochemistry or other genetic examinations are important even if 18F-FDG uptake on PET-CT seems to be a false-positive because of the possibility of a sarcoid reaction.

Brief report on similar mutational changes in neurofibromatosis type 2 gene in minute pulmonary meningothelial-like nodule and meningioma of the central nervous system.

INTRODUCTION: Minute Pulmonary Meningothelial-like Nodules (MPMNs) are usually detected incidentally adjacent to lung cancer tissue. The pathogenesis is unknown. MPMNs reportedly share the status of neurofibromatosis (NF)-2 gene with meningiomas of the central nervous system. RESULTS: Immunohistochemical staining of two MPMNs revealed they were positive for epithelial membrane antigen (EMA), vimentin, CD56, and progesterone. We identified deletion of the NF-2 gene in two MPMNs and one CNS meningioma. CONCLUSIONS: MPMN and CNS meningioma may develop via the same mechanism through NF-2 translocation. Further studies are required to elucidate the genetic similarities between these entities. METHODS: We used fluorescence in situ hybridization to explore the status of the NF-2 gene in MPMNs and compare it with that of CNS meningiomas. We used a commercially available locus-specific probe for the NF-2 region to analyze whole tissue sections of two MPMNs and two CNS meningiomas by fluorescence in situ hybridization.

Endoscopic Mucosal Resection Performed Underwater for Nonampullary Duodenal Epithelial Tumor: Evaluation of Feasibility and Safety.

OBJECTIVES: Recently, opportunities to encounter superficial nonampullary duodenal epithelial tumor (SNADET) have increased. EMR and ESD are performed to treat SNADET. However, the rate of perforation is higher than that of other gastrointestinal lesions, regardless of which method is used. Underwater EMR (UW-EMR) is immersion treatment of SNADET, which has low risk of perforation and can remove lesions safely and completely. In the present study, we retrospectively investigated patients in whom UW-EMR was performed to evaluate the feasibility and safety of UW-EMR for the treatment of SNADET. METHODS: The primary endpoint was to evaluate the feasibility of UW-EMR for the treatment of SNADET, and secondary objective was to determine the operation's safety. RESULTS: There were 14 participants, with a total of 16 lesions, who underwent UW-EMR between August 2015 and December 2017. Histological heteromorphism revealed that seven patients had low-grade adenoma, seven had high-grade adenoma, and two had adenocarcinoma. En bloc resection was performed in 14 lesions. In two patients, nodular lesions were observed in the scar and biopsy confirmed recurrences. There were no serious adverse events including bleeding or perforation. CONCLUSIONS: UW-EMR may be a safe and effective treatment method for SNADET, if its therapeutic indication is adequately considered.