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Testicular teratomas are the major histologic type of testicular germ cell tumors and their incidence continues to grow. Moreover, teratomas can develop from undifferentiated cells in induced pluripotent stem (iPS) cell transplantation therapy, seriously hampering the progress of regenerative medicine. Germinal center-associated nuclear protein (GANP) is thought to be important to the biogenetic control of primordial germ cells and is among the genes susceptible to testicular germ cell tumors. Thus, we analyzed the expression of GANP in human testicular postpubertal-type teratomas and established a novel mouse model to reveal the association between GANP and teratomagenesis. We analyzed 31 cases of human testicular postpubertal-type teratomas and, in all cases, GANP was overexpressed. The aberrant expression was also detected in germ cell neoplasia in situ accompanied by the teratoma. GANP expression was particularly high in the epithelia of the epidermis, cutaneous appendages, and trachea-like ciliated epithelium. To further clarify the association between GANP and teratomagenesis, we established a novel teratomagenesis mouse model (CAG-ganp

Malignant pleural mesothelioma (MPM) is a malignant neoplasm of the pleura caused by asbestos exposure. For diagnosis of MPM, immunohistochemistry using multiple markers is recommended to rule out differential diagnoses, such as pulmonary adenocarcinoma. However, the specificity of currently used markers is not fully satisfactory. We previously developed a monoclonal antibody named S1, which recognizes 6-sulfo sialyl Lewis x, an L-selectin ligand expressed on high endothelial venules. During the screening process, we discovered that this antibody stained normal pleural mesothelium. This finding prompted us to hypothesize that the epitope recognized by S1 might serve as a new diagnostic marker for MPM.To test this hypothesis, we immunostained human MPM (n = 22) and lung adenocarcinoma (n = 25) tissues using S1 antibody.77.3% of MPM were S1 positive, and if limited to epithelioid type, the positivity rate was 100%, while that of lung adenocarcinoma was only 36.0%. Statistical analysis revealed a significant difference in the S1 positivity rate between each disease. Furthermore, immunohistochemistry using a series of anti-carbohydrate antibodies combined with glycosidase digestion revealed the structure of sulfated glycans expressed in MPM to be 6-sulfo sialyl N-acetyllactosamine attached to core 2-branched O-glycans.We propose that the S1 glycoepitope could serve as a new diagnostic marker for MPM.

東京電力福島第一原子力発電所の廃炉において発生すると考えられる様々な種類の廃棄物は，その汚染レベルに応じて廃棄方法が決定される．様々な放射性物質や核燃料物質のうち，ウランは半減期が非常に長く，放射線計測による検出が難しい場合がある．そこで，本研究では廃棄物表面のウラン汚染レベルを迅速にスクリーニングする方法として，蛍光X 線分析法に基づく手法を提案する．硝酸ウラニル溶液を滴下したろ紙をポリプロピレン製片側粘着テープとマイラ膜で密封し，これをコンクリート固化物，ポリエチレンブロック，ガラス板に重ねたものを，これらの物質の表面がウランに汚染されたもののモデルとした．このモデルの蛍光X 線分析を行った結果，ウラン添加量とU Lα 線の信号強度の相関はどのモデルでもほぼ同じ傾きの直線となった．ただし，コンクリートはウランを含んでいるので，縦軸切片が有意な値を持った．

Background/Aim: Cancer cells with high anchorage independence can survive and proliferate in the absence of adhesion to the extracellular matrix. Under anchorage-independent conditions, cancer cells adhere to each other and form aggregates to overcome various stresses. In this study, we investigated the cytomorphology and gene expression signatures of oral cancer cell aggregates. Materials and Methods: Two oral cancer-derived cell lines, SAS and HSC-3 cells, were cultured in a low-attachment plate and their cytomorphologies were observed. The transcriptome between attached and detached SAS cells was examined using gene expression microarrays. Subsequently, gene enrichment analysis and Ingenuity Pathway Analysis were performed. Gene expression changes under attached, detached, and re-attached conditions were measured via RT-qPCR. Results: While SAS cells formed multiple round-shaped aggregates, HSC-3 cells, which had lower anchorage independence, did not form aggregates efficiently. Each SAS cell in the aggregate was linked by desmosomes and tight junctions. Comparative transcriptomic analysis revealed 1,698 differentially expressed genes (DEGs) between attached and detached SAS cells. The DEGs were associated with various functions and processes, including cell adhesion. Moreover, under the detached condition, the expression of some epithelial genes (DSC3, DSP, CLDN1 and OCLN) were up-regulated. The changes in both cytomorphology and epithelial gene expression under the detached condition overall returned to their original ones when cells re-attached. Conclusion: The results suggest specific cytomorphological and gene expression changes in oral cancer cell aggregates. Our findings provide insights into the mechanisms underlying anchorage-independent oral cancer cell aggregation and reveal previously unknown potential diagnostic and therapeutic molecules.

A Japanese man in the present study experienced acute weakness in his right leg as a two year old. The strength in his leg gradually recovered and developed, and he could play golf and climb mountains up to around the age of 50. From approximately 55 years of age, he became unable to stand up from a stooped position. Muscle weakness and atrophy spread to his right arm, and an electromyography revealed a neurogenic pattern in his lower and upper extremities. The patient was diagnosed as having post-poliomyelitis syndrome (PPS). Numbness in both the legs and pain in the buttocks occurred after 60 years of age. Computed tomography and magnetic resonance imaging at that time revealed spondylosis and protrusion of an osteophye in lower thoracic vertebrae compressing the second lumbar segment of the spinal cord. He died of malignant lymphoma and acute interstitial pneumonia at 80 years of age. Pathological examination revealed transverse myelopathy at the second lumbar segment of the spinal cord and total necrosis. The anterior horn and the intermediate zone of the third and fourth lumbar segments of the spinal cord on the right side were atrophic and diffusely gliotic. An oval-shaped plaque-like lesion was observed in the right anterior horn at the third and fourth lumbar segments of the spinal cord. Neurons and synaptophysin immunoreactivity had completely disappeared in the plaque-like lesion. A striking spread of vimentin-immunoreactive cells was found corresponding to the lesion, while glial fibrillary acidic protein-immunoreactive astrocytes existed evenly in the anterior horn and intermediate zone on both sides of the third and fourth lumber segments of the spinal cord. Virological examination using the autopsied materials was negative for poliovirus. Neither transactivation response DNA-binding protein of 43 kDa-immunoreactive inclusion nor Bunina body was seen in the spinal cord. The present paper demonstrates new findings of a noteworthy response of the vimentin-immunoreactive cells within the peculiar "plaque-like lesion" in the PPS.

Breast cancer, the most common malignancy among women, is closely associated with mutations in the tumor suppressor gene BRCA. DSS1, a component of the TRanscription-EXport-2 (TREX-2) complex involved in transcription and mRNA nuclear export, stabilizes BRCA2 expression. DSS1 is also related to poor prognosis in patients with breast cancer owing to the induction of chemoresistance. Recently, BRCA2 was shown to be associated with the TREX-2 component PCID2, which prevents DNA:RNA hybrid R-loop formation and transcription-coupled DNA damage. This study aimed to elucidate the involvement of these TREX-2 components and BRCA2 in the chemosensitivity of breast carcinomas. Our results showed that compared with that in normal breast tissues, DSS1 expression was upregulated in human breast carcinoma, whereas PCID2 expression was comparable between normal and malignant tissues. We then compared patient survival time among groups divided by high or low expressions of DSS1, BRCA2, and PCID2. Increased DSS1 expression was significantly correlated with poor prognosis in recurrence-free survival time, whereas no differences were detected in the high and low BRCA2 and PCID2 expression groups. We performed in vitro analyses, including propidium iodide nuclear staining, single-cell gel electrophoresis, and clonogenic survival assays, using breast carcinoma cell lines. The results confirmed that DSS1 depletion significantly increased chemosensitivity, whereas overexpression conferred chemoresistance to breast cancer cell lines; however, BRCA2 expression did not affect chemosensitivity. Similar to DSS1, PCID2 expression was also inversely correlated with chemosensitivity. These results strongly suggest that DSS1 and PCID2 depletion is closely associated with increased chemosensitivity via BRCA2-independent DNA damage. Together with the finding that DSS1 is not highly expressed in normal breast tissues, these results demonstrate that DSS1 depletion confers a druggable trait and may contribute to the development of novel chemotherapeutic strategies to treat DSS1-depleted breast carcinomas independent of BRCA2 mutations.

The influence of atmospheric water vapor on the kinetics of the thermal decomposition of perlite concrete, which is used in the construction of sodium-cooled fast reactor (SFR) plants, was investigated. Changes in the overall thermal behavior were systematically tracked using humidity-controlled thermogravimetry (TG) at various heating rates (β) and atmospheric water vapor pressures (p(H2O)). The multistep process, mainly composed of the thermally-induced removal of various types of water molecules in the cement matrix and the thermal decompositions of Ca(OH)2 and CaCO3, was successfully separated into component reaction steps using kinetic deconvolution analysis (KDA) based on a cumulative kinetic equation. During the thermal dehydration steps, three derivative TG peaks became more clearly distinguishable and shifted to higher temperatures with increasing p(H2O). A significant retardation effect of p(H2O) was observed for the thermal decomposition of Ca(OH)2. Conversely, a slight but detectable catalytic effect of p(H2O) was observed for the thermal decomposition of CaCO3. Through isoconversional analysis of the kinetic curves extracted using KDA, universal kinetic descriptions for the thermal decompositions of Ca(OH)2 and CaCO3 over different β and p(H2O) values were achieved by introducing accommodation functions considering the effect of p(H2O) into the fundamental kinetic equation. The achieved universal kinetic descriptions for the thermal decompositions of Ca(OH)2 and CaCO3 can be introduced into the cumulative kinetic equation for the overall thermal decomposition of perlite concrete as a means to improve the kinetic information used in SFR plant simulation systems for safety assessment.

The thermal behavior of perlite concrete, which is used in sodium-cooled fast reactor plants, was subjected to kinetic modeling to gather the fundamental data for establishing a reliable safety assessment system. In this study, the influence of atmospheric CO2 on the multistep kinetic behavior of perlite concrete was investigated in detail by separating the component reaction steps using kinetic deconvolution analysis (KDA) based on a cumulative kinetic equation. The carbonation of Ca(OH)2 during its thermal decomposition was identified as a specific process observed in the presence of atmospheric CO2. The process was characterized by KDA as the successive thermal decomposition of Ca(OH)2 to form CaO and the subsequent carbonation of CaO. A shift in the temperature range of the overall carbonation process to higher temperatures with increase in partial pressure of CO2 (p(CO2)) was also identified as a specific phenomenon. The thermal decomposition of CaCO3 was separated from the multistep thermal decomposition of the perlite concrete using KDA and analyzed kinetically considering the influence of p(CO2). A universal kinetic description over different temperatures and p(CO2) values was achieved by introducing an accommodation function composed of p(CO2) and the equilibrium CO2 pressure for the reaction. Introduction of the modified kinetic equation with the accommodation function into the corresponding reaction step of the cumulative kinetic equation enables a universal kinetic description of the overall thermal decomposition of perlite concrete over different temperature and p(CO2) conditions.

At TEPCO's Fukushima Daiichi Nuclear Power Station, contaminated water is treated after removing radionuclides. Fuel debris removal, which is commencing soon, may discharge water contaminated with actinides, such as uranium, neptunium, and plutonium, requiring screening prior to treatment. In this paper, we propose an actinide screening method based on X-ray fluorescence (XRF) analysis. In this method, actinides are collected on a chelating disk [1] containing iminodiacetic acid as a chelating agent, and their L-X rays are analyzed using an energy-dispersive XRF device. The Br Kβ, Rb Kα, and Sr Kα peaks overlap with the Lα peaks of U, Np, and Pu, which interferes with the analysis. Of these, the Br Kβ and Rb Kα peaks are located in the lower energy region of the U Lα peak and can be separated by peak fitting [2]. Furthermore, the Sr Kα peak is located between the Np Lα and Pu Lα peaks, hindering its separation by peak fitting owing to the proximity of the peaks. Therefore, before collecting the actinides in the sample solution on the chelating disk, Sr is removed by loading through a Sr Rad Disk [3], which adsorbs Sr well. First, simulated contaminated water containing Sr was mixed with same amount of 4 mol/L nitric acid and a solution containing 200 ng of U, Np, and Pu. This was loaded through a Sr Rad Disk. To the filtrate, 1 mol/L ammonium acetate were added, and pH was adjusted to 5.6. The chelating disk of 22.5 mm diameter was conditioned with methanol, 2 mol/L nitric acid, ultrapure water, and 0.1 mol/L ammonium acetate solution (pH 5.6). Actinides were collected on the disc by loading the sample solution through chelate discs. The XRF measurement of the disc was performed using an Epsilon 4 tabletop XRF spectrometer (PANalytical, Malvern Instruments, Spectris plc, England). The X-ray tube voltage and current were set to 50 kV and 0.3 mA, respectively, and the X-ray accumulation time for each spectral measurement was 300 s. In the measured XRF spectrum, the Lα peaks of U, Np, and Pu were clearly observed. In this presentation, we explain the features and benefits of this technique. This research project was conducted as a regulatory supporting research funded by the Secretariat of Nuclear Regulation Authority (S/NRA/R) in Japan. [1] T. Inui et al., X-ray spectrometry 40, 2011, 301–305. [2] H. Yoshii et al., Spectrochimica Acta B, 189, 2022, 106368. [3] LL. Smith et al., Radiochemical Acta 73, 1996, 165–170., European Conference on X-ray Spectrometry 2022

【緒言】東京電力福島第一原子力発電所の廃炉作業において発生する可能性のある汚染水中のアクチニド (U, Np, Pu) を迅速にスクリーニングする手法が必要とされている．汚染水をキレートディスクに通液して捕集し，蛍光X線分析する方法を検討しているが，Np Lα線やPu Lα線とSr Kα線が重なるので，事前にSrを除去しておくことが望ましい．本研究では，ストロンチウムラドディスクを用いて，事前にSrを除去しておく手法を開発した． 【実験】ストロンチウムラドディスク1)は，試料溶液の硝酸濃度が2 mol/L程度の時にストロンチウムを効率よく吸着する．そこで，模擬汚染水としてのがれき純水浸漬液に等量の4 mol/L硝酸を加えて硝酸濃度を2 mol/Lとし，そこに200 ngのU, Np, Puを添加した．コンディショニングしたストロンチウムラドディスクに通液し，そのろ液を回収した．キレートディスクはpH5.6で通液するのが標準的な手法とされているので2)，液量の10%の1 mol/L酢酸アンモニウム水溶液を緩衝液として加え，pHを5.6に調整してから通液した．ディスクはマイラ膜とポリプロピレン製粘着テープで密封し，卓上型蛍光Ｘ線分析装置Epsilon4 (パナリティカル) で測定した．測定条件は管電圧50 kV，管電流0.3 mA，測定時間3600sである． 【結果と考察】ストロンチウムラドディスク (SrD) とキレートディスク(ChD) の蛍光Ｘ線スペクトルを図1に示す．ストロンチウムラドディスクでSrが完全に除去されているため，キレートディスクにはSr Kα線は表れておらず，明瞭なU Lα線，Np Lα線，Pu Lα線が観測されている．この手法によるU, Np, Puの回収率はそれぞれ99%, 66%, 46%だった． 1)T. Inui et al., X-ray spectrometry 2011, 40, 301–305. 2)古庄義明 et al., 分析化学 2008, 57, 969–989., 日本分析化学会 第82回分析化学討論会

Germinal center-associated nuclear protein (GANP) is a unique and multifunctional protein that plays a critical role in cell biology, neurodegenerative disorders, immunohematology, and oncogenesis. GANP is an orthologue of Saccharomyces Sac3, one of the components of the transcription export 2 (TREX-2) complex and a messenger RNA (mRNA) nuclear export factor. GANP is widely conserved in all mammals, including humans. Although GANP was originally discovered as a molecule upregulated in the germinal centers of secondary lymphoid follicles in peripheral lymphoid organs, it is expressed ubiquitously in many tissues. It serves numerous functions, including making up part of the mammalian TREX-2 complex; mRNA nuclear export via nuclear pores; prevention of R-loop formation, genomic instability, and hyper-recombination; and B-cell affinity maturation. In this review, we first overview the extensive analyses that have revealed the basic functions of GANP and its ancestor molecule Sac3, including mRNA nuclear export and regulation of R-loop formation. We then describe how aberrant expression of GANP is significantly associated with cancer development. Moreover, we discuss a crucial role for GANP in B-cell development, especially affinity maturation in germinal centers. Finally, we illustrate that overexpression of GANP in B cells leads to lymphomagenesis resembling Hodgkin lymphoma derived from germinal center B cells, and that GANP may be involved in transdifferentiation of B cells to macrophages, which strongly affects Hodgkin lymphomagenesis.

EWSR1-CREM gene fusions were recently discovered in several mesenchymal and epithelial tumors, including myxoid mesenchymal tumors of the central nervous system, rare cases of soft tissue clear cell sarcoma and angiomatoid fibrous histiocytoma, and hyalinizing clear cell carcinoma, which implicates the potential phenotypic diversities of tumors harboring an EWSR1-CREM fusion. We herein present an exceedingly indolent pulmonary mesenchymal tumor showing distinctive clinicopathological features. This tumor histologically displayed a small nest and alveolar pattern consisting of monomorphic clear cells intermingled with dilated anastomosing vasculature. Immunophenotypically, tumor cells were positive for vimentin and focally positive for synaptophysin, but negative for many immunohistochemical panels including keratins, EMA, desmin, mesothelial markers, melanotic markers, smooth muscle actin, inhibin and S-100 protein. Interestingly, RNA sequencing identified an in-frame EWSR1-CREM fusion, which was confirmed by subsequent real-time/reverse transcription polymerase chain reaction and fluorescence in situ hybridization assay. Clinical follow-up showed no evidence of recurrence and metastasis. Our pathological findings further expand the phenotypic spectrum of tumors associated with EWSR1-CREM fusions, implying the emergence of a possible novel tumor entity.

This study aimed to evaluate the practical usefulness of kinetic deconvolution analysis (kDa) as a means to obtain the kinetic information on specific reaction steps that characterize the thermal properties of materials for various purposes. The partially overlapping multistep thermal decomposition of Maya Blue (MB)-type pigments was used as an example reaction. Red and yellow MB-type pigment materials, composed of a fibrous clay mineral and an organic dye, were synthesized using palygorskite and sepiolite as the clay minerals and Methyl Red and Alizarin as red and yellow dyes, respectively. The multistep thermal decompositions of the MB-type pigments were investigated using thermogravimetry. The thermoanalytical data were deconvoluted into individual component reaction steps using an empirical kDa technique based on a cumulative kinetic equation that considers the contribution of each reaction step to the overall thermal decomposition. By comparing the kDa results for the thermal decomposition of the composites with those for the decomposition of pure palygorskite and sepiolite, the thermal decomposition steps for the incorporated organic dyes were extracted from the multistep thermal decompositions of the MB-type pigments. Finally, the thermal stabilities of MB-type pigments comprising different clay minerals and organic dyes were compared using the kinetic results extracted for the reaction step associated with the decomposition of the organic dyes.

This note is concerned with the question of why and how my research interest has been changed from general equilibrium theory to the economics of uncertainty. Although it is fundamentally a personal perspective, it is expected to have historical implications as well, thus serving as a good guide toward the new horizon of integrated social science. When I started my research life, so many people were involved in the “Cold War” between the capitalist bloc and the socialist bloc. In 1968, to escape from the Japanese university disturbance, I applied for the graduate program at the University of Rochester, with Professor Lionel W. McKenzie being a towering figure. Later, when I took care of the math econ sequence at the University of Pittsburgh, I began to have a feeling of doubt about the practical applicability of general equilibrium theory a la McKenzie. Partly being motivated by a suggestion from Professor Oscar Morgenstern, who came to Pittsburgh for an academic lecture, I started to shift my research area from pure and abstract theories to more practical and applied subjects including the economics of uncertainty. In 1989, all of a sudden, the seemingly invincible Berlin Wall turned down, being followed by the collapse of the mighty Soviet Union. In the dreadful year of 2008, the world economies were involved in the most serious crisis since the Great Depression on the 1930s. At present, we are living in the “New Age of Uncertainty,” hoping for the coming of the second Keynes and/or the second Knight. Thomas Piketty’s new book on economic inequality would possibly lead to the promotion of an integrated social science in the new century.

Sarcoidosis is a rare disease of isolated or diffuse granulomatous inflammation. Although any organs can be affected by sarcoidosis, cardiac sarcoidosis is a fatal disorder, and it is crucial to accurately diagnose it to prevent sudden death due to dysrhythmia. Although endomyocardial biopsy is invasive and has limited sensitivity for identifying granulomas, it is the only modality that yields a definitive diagnosis of cardiac sarcoidosis. It is imperative to develop novel pathological approaches for the precise diagnosis of cardiac sarcoidosis. Here, we aimed to discuss commonly used diagnostic criteria for cardiac sarcoidosis and to summarize useful and novel histopathologic criteria of cardiac sarcoidosis. While classical histologic observations including noncaseating granulomas and multinucleated giant cells (typically Langhans type) are the most important findings, others such as microgranulomas, CD68+ CD163− pro-inflammatory (M1) macrophage accumulation, CD4/CD8 T-cell ratio, Cutibacterium acnes components, lymphangiogenesis, confluent fibrosis, and fatty infiltration may help to improve the sensitivity of endomyocardial biopsy for detecting cardiac sarcoidosis. These novel histologic findings are based on the pathology of cardiac sarcoidosis. We also discussed the principal histologic differential diagnoses of cardiac sarcoidosis, such as tuberculosis myocarditis, fungal myocarditis, giant cell myocarditis, and dilated cardiomyopathy.

AI has led to extraordinary medical breakthroughs, one of which is the digitisation of pathological slides which negates the need for classical optical microscopes. Also thanks to AI, clinicians and researchers can access great swathes of data that can be used to enhance understanding of diseases and improve patient outcomes. In his research, Dr Yasuhiro Sakai is exploring the possibilities facilitated by AI and big data, with a focus on gastric cancer. He has established the Japan Pathology AI Diagnostics Project (JP-AID) and is collaborating with Dr Mai Iwaya and Professor Kensaku Mori, with input from other researchers based at Shinshu University, Fujita Health University, Nagoya University and the National Institute of Informatics. The researchers are using AI to evaluate the risk factors of gastric cancer, including the degree of chronic gastritis, neutrophil infiltration and intestinal metaplasia. In using AI, the researchers aim to overcome limitations associated with the 'Updated Sydney System (USS)', which is a pathological scoring system for gastritis. Limitations of the USS are that the scoring system is subjective and in order to produce precise scoring, substantial gastrointestinal pathology experience is required. Sakai and the team are using AI to create new methods for evaluating gastritis that are efficient and will save time for pathologists.

Background Partner of Sld five 3 (Psf3) is a member of the heterotetrameric complex that consists of SLD5, Psf1, Psf2, and Psf3. We have shown in previous studies that high Psf3 expression was a poor prognostic marker for pulmonary adenocarcinoma. Here, we statistically evaluated the relationship between clinicopathologic factors and Psf3 expression in stage I pulmonary adenocarcinoma. Methods A total of 583 patients who had undergone complete resection of stage I pulmonary adenocarcinoma from January 2002 to December 2009 were included in the study. Tissue microarrays were performed, and the resected tumors were divided into groups according to Psf3 expression. Results Of 583 patients, high expression of Psf3 was observed in 211 (36.2%) and low expression of Psf3 observed in 372 (63.8%) patients. Among stage I patients, the five-year survival rate was 76.7% in the Psf3 high expression group and 90.9% in the Psf3 low expression group (P < 0.0001). On multivariate analysis, Psf3 was found to be the independent prognostic factor. Among stage I patients in the Psf3 high expression group, a significantly greater five-year survival rate was observed in patients who received postoperative chemotherapy with tegafur-uracil than in those who underwent surgery alone (P < 0.0001). In contrast, among stage I patients in the Psf3 low expression group, no difference was found in the five-year survival, regardless of the presence or absence of tegafur-uracil (P = 0.873). Conclusion The Psf3 expression was an independent prognostic factor and could be a biomarker of adjuvant tegafur-uracil for stage I pulmonary adenocarcinoma. Key points Significant findings of the study: The Psf3 expression could be a biomarker of adjuvant tegafur-uracil administration for stage I pulmonary adenocarcinoma. What this study adds: Appropriate patients of adjuvant chemotherapy for stage I pulmonary adenocarcinoma using Psf3 expression could be selected.

For the long-term survival of a patient with renal cell carcinoma and a vena cava tumor thrombus, total resection is desired: inoperable patients are sometimes treated with drugs. The effect of the presurgical use of nivolumab, an anti-programmed cell death 1 (PD-1) antibody drug, has been described. Our patient had inoperable renal cancer with an inferior vena cava tumor thrombus. We were able to downsize the tumor to operable size by administrating nivolumab. The patient underwent a nephrectomy and thrombectomy safely. Pathological findings revealed papillary renal cell carcinoma type 2. No viable cells were identified in the removed thrombus. Anti-programmed cell death ligand 1 was expressed on the cell membrane in approximately 20% of the tumor cells, and PD-1 positive tumor-ifiltrating immune cells had infiltrated particularly at the edge of the tumor. This case indicates the positive effect of the presurgical use of nivolumab for advanced papillary renal cell carcinoma.

Objective: Helicobacter pylori eradication is expected to prevent gastric cancer. However, morphological alterations after eradication often hinder accurate diagnosis. Therefore, we evaluated endoscopic and histological changes in gastric tumors after eradication of H. pylori in a time-dependent manner. Methods: We classified 144 cases of endoscopic submucosal dissection (ESD) of early gastric cancer into the following categories: (i) patients positive for H. pylori with no eradication history, (ii) patients positive for H. pylori who underwent ESD 2 months after eradication, (iii) patients negative for H. pylori with an eradication history of at least 6 months before ESD, and (iv) patients negative for H. pylori with an unknown history. We compared endoscopic and histological factors between the groups. Results: The characteristics of cancers positive for H. pylori were exploding shape, superficial high-grade atypical epithelium, and a surface proliferating zone. H. pylori eradication induced a series of endoscopic and histological changes, including shape ­depression, appearance of surface regenerative and lower-grade atypical epithelium, and a downward shift of the proliferative zone within a period as short as 2 months. Conclusion: H. pylori eradication rapidly causes cancer regression and leads to tumor shrinkage, diminished atypism, and shortened proliferative zone, resulting in drastic morphological changes.