Relapsing cytokine release syndrome in a patient with metastatic renal cell carcinoma treated with pembrolizumab and axitinib therapy.

As immune checkpoint inhibitors become more widely available, the optimal management of immune-related adverse events (irAEs) is becoming increasingly important. Although irAEs are diverse, reports on cytokine release syndrome are rare. Here, we report a case of a 48-year-old man with relapsing cytokine release syndrome after receiving pembrolizumab and axitinib combination therapy for metastatic renal cell carcinoma. During dose reduction of prednisolone for immune-related hepatitis on day 33 after starting pembrolizumab plus axitinib, the patient suddenly developed abdominal pain, and a few hours later became hypotensive and poorly oxygenated. Despite the use of a ventilator and high doses of catecholamines, blood pressure and oxygenation could not be maintained. Extracorporeal membrane oxygenation and intra-aortic balloon pumping were also administered. The cytokine release syndrome (CRS) was treated with tocilizumab, and his general condition improved. Lower-grade CRS relapsed four times despite a moderate dose of oral prednisolone with mycophenolate mofetil or tacrolimus. After gradual reduction in prednisolone over 5 months, the patient was discharged from the hospital. Partial remission of renal cell carcinoma continued for 21 months, and salvage radical nephrectomy was performed. The patient remained disease-free without the need for further treatment 9 months after surgery.

Outcomes in patients with high- and very high-risk localized prostate cancer treated with definitive IMRT and long-term hormone therapy.

BACKGROUND: The aim of this study was to evaluate the effectiveness of intensity-modulated radiation therapy in combination with long-term androgen deprivation therapy for high-risk and very high-risk localized prostate cancer while also investigating factors associated with the therapeutic effect. METHODS: Men who fulfilled criteria for the National Comprehensive Cancer Network high-risk or very high-risk localized prostate cancer and were treated with definitive intensity-modulated radiation therapy (74-78 Gy) of the prostate and the seminal vesicle combined with androgen deprivation therapy in our institution from 2007 to 2016 were identified (n = 197). In principle, patients received androgen deprivation therapy for 3-6 months before radiation, concurrently, and for 2 years after completion of intensity-modulated radiation therapy. RESULTS: The median follow-up period was 96 months. The 5-year and 10-year overall survival rates in the overall population were 96.9% and 89.3%, respectively. The 5-year and 10-year cumulative incidence rates of biochemical failure were 2.5% and 16.3% in the high-risk group, and 8.6% and 32.0% in the very high-risk group, respectively, indicating a significant difference between the two groups (P = 0.023). Grade Group 5 and younger age (cutoff: 70 years old) were independent predictors of recurrence (P = 0.016 and 0.017, respectively). Patients exhibiting biochemical failure within <18 months after completion of androgen deprivation therapy displayed an increased risk of cancer-specific mortality (P = 0.039) when contrasted with those who had a longer interval to biochemical failure. CONCLUSIONS: Patients with the National Comprehensive Cancer Network very high-risk prostate cancer, particularly those with Grade Group 5 and younger age, showed worse outcomes following intensity-modulated radiation therapy and long-term androgen deprivation therapy.

Increasing age predicts adverse pathology including intraductal carcinoma of the prostate and cribriform patterns in deferred radical prostatectomy after upfront active surveillance for Gleason grade group 1 prostate cancer: analysis of prospective observational study cohort.

BACKGROUND: In men undergoing upfront active surveillance, predictors of adverse pathology in radical prostatectomy specimens, including intraductal carcinoma of the prostate and cribriform patterns, remain unknown. Therefore, we aimed to examine whether adverse pathology in radical prostatectomy specimens could be predicted using preoperative patient characteristics. METHODS: We re-reviewed available radical prostatectomy specimens from 1035 men prospectively enrolled in the PRIAS-JAPAN cohort between January 2010 and September 2020. We defined adverse pathology on radical prostatectomy specimens as Gleason grade group ≥3, pT stage ≥3, pN positivity or the presence of intraductal carcinoma of the prostate or cribriform patterns. We also examined the predictive factors associated with adverse pathology. RESULTS: All men analyzed had Gleason grade group 1 specimens at active surveillance enrolment. The incidence of adverse pathologies was 48.9% (with intraductal carcinoma of the prostate or cribriform patterns, 33.6%; without them, 15.3%). The addition of intraductal carcinoma of the prostate or cribriform patterns to the definition of adverse pathology increased the incidence by 10.9%. Patients showing adverse pathology with intraductal carcinoma of the prostate or cribriform patterns had lower biochemical recurrence-free survival (log-rank P = 0.0166). Increasing age at active surveillance enrolment and before radical prostatectomy was the only predictive factor for adverse pathology (odds ratio: 1.1, 95% confidence interval: 1.02-1.19, P = 0.0178; odds ratio: 1.12, 95% confidence interval: 1.02-1.22, P = 0.0126). CONCLUSIONS: Increasing age could be a predictive factor for adverse pathology. Our findings suggest that older men could potentially derive advantages from adhering to the examination schedule in active surveillance.

[A Case of Primary Signet Ring Cell Carcinoma of the Urinary Bladder Showing Effectiveness of Chemotherapy with Gemcitabine and Cisplatin].

A 55-year-old female presented to the hospital with a complaint of gross hematuria. Transurethral resection of bladder tumor was performed. The specimens pathologically showed signet ring cells and no urothelial carcinoma components. Magnetic resonance imaging and computed tomographic (CT) scan revealed bladder tumor, cervical metastasis, bilateral ovarian metastasis, and multiple lymph node metastasis. She was diagnosed with a primary signet ring cell carcinoma of the urinary bladder with cT3bN2M1, and was treated with chemotherapy of gemcitabine and cisplatin combination (GC). After 2 cycles of GC, the value of CEA which was elevated to 106 ng/ml before treatment, became negative. CT scan showed that her disease had successfully responded to the chemotherapy, and remained efficacious till the end of 6 cycles. The patient subsequently received 1 cycle of gemcitabine and nedaplatin and 3 cycles of avelumab due to renal insufficiency. Yet, 14 months after diagnosis, cerebellar metastases appeared and the patient died of meningeal carcinomatosis.

Spontaneous bladder rupture attributable to a radical hysterectomy-associated neurogenic bladder in patients with cervical cancer: A case report and literature review.

INTRODUCTION AND IMPORTANCE: Spontaneous bladder rupture (SBR) is an extremely rare urological emergency. Herein we report a rare case of SBR in a postoperative cervical cancer patient, which was attributable to bladder distension due to a radical hysterectomy-associated neurogenic bladder. CASE PRESENTATION: A 74-year-old nulliparous Japanese patient with cervical cancer (pT1b3N0M0) presented with acute abdominal pain nine days after a radical hysterectomy. The pretreatment workup included plain computed tomography (CT) revealed the presence of ascites in the absence of gastrointestinal perforation. The patient was initially diagnosed with generalized bacterial peritonitis and treated with antibiotics. Urine outflow was noted 5 days later from the vaginal stump. Subsequent contrast-enhanced CT demonstrated a bladder wall defect with presence of contrast medium in the abdominal cavity. The patient was diagnosed with SBR and was conservatively treated with antibiotics and prolonged catheterization (4 weeks); these measures showed no signs of therapeutic efficacy. The patient was subsequently treated surgically with an ileal conduit urinary diversion. The patient is currently free of disease. CLINICAL DISCUSSION: A literature review revealed that a history of pelvic radiotherapy is the main predisposing factor for SBR in women with cervical cancer. Our case serves to alert physicians that SBR should be considered a differential diagnosis in postoperative cervical cancer patients without a history of pelvic radiotherapy who experience generalized peritonitis symptoms or present as an acute abdomen. CONCLUSION: SBR can develop in cervical cancer patients without a history of radiotherapy. This differential diagnosis should be considered in patients with a radical hysterectomy-associated neurogenic bladder.

Clinical outcomes of intraductal carcinoma or cribriform in radical prostatectomy specimens of men opting for active surveillance: data from the PRIAS-JAPAN study.

BACKGROUND: Among early stage prostate cancer patients, intraductal carcinoma of the prostate (IDC-P) and invasive cribriform are key prognostic factors; however, their presence and clinical significance following active surveillance (AS) are unknown. In men who opted for AS, we aimed to examine the presence and impact of IDC-P or cribriform, utilizing radical prostatectomy (RP) specimens. METHODS: We re-reviewed 137 RP specimens available in the PRIAS-JAPAN prospective cohort between January 2010 and September 2020. We assessed the presence of IDC-P or cribriform, and compared the patients' characteristics and prostate-specific antigen (PSA) recurrence-free survival after RP between groups with and without IDC-P or cribriform. In addition, we examined the predictive factors associated with IDC-P or cribriform. RESULTS: The percentage of patients with IDC-P or cribriform presence was 34.3% (47 patients). IDC-P or cribriform pattern was more abundant in the higher Gleason grade group in RP specimens (P < 0.001). The rates of PSA recurrence-free survival were significantly lower in the IDC-P or cribriform groups than in those without them (log rank P = 0.0211). There was no association between IDC-P or cribriform on RP with the Prostate Imaging-Reporting and Data System (PI-RADS) 4,5 score on magnetic resonance imaging (MRI) before RP even with adjustments for other covariates (OR, 1.43; 95% confidence interval [CI] 0.511-3.980, P = 0.497). CONCLUSIONS: IDC-P or cribriform comprised approximately one-third of all RP specimens in men who underwent RP following AS, confirming their prognostic significance.

Efficacy of cabazitaxel in patients with metastatic castration-resistant prostate cancer: A single-center study in Japan.

OBJECTIVES: Cabazitaxel is a next-generation taxane that can prolong overall survival after docetaxel treatment in patients with metastatic castration-resistant prostate cancer. However, the efficacy of cabazitaxel varies among these patients. The clinical indicators of the prognosis after cabazitaxel treatment were analyzed. METHODS: A retrospective review of patients who received cabazitaxel between February 2015 and June 2021 was performed. All patients had metastatic castration-resistant prostate cancer. Prognostic factors for prostate-specific antigen progression-free and overall survival were analyzed by Cox proportional-hazards analysis and the log-rank test. RESULTS: The study comprised 57 patients who received cabazitaxel (median 4 cycles, range 1-27) at a starting dose of 15-25 mg/m2 . The median age and follow-up duration were 70 years and 9.2 months. The median prostate-specific antigen progression-free survival and overall survival were 2.6 and 10.5 months, respectively. Univariate analysis showed that previous androgen receptor-axis-targeted therapy before cabazitaxel treatment was the only significant risk factor (hazard ratio 2.784, p = 0.022) for prostate-specific antigen progression-free survival. Multivariate analysis for overall survival revealed that poor performance status (≥1) (hazard ratio 2.107, p = 0.039), low hemoglobin (hazard ratio 0.142, p = 0.010), and high neutrophil-lymphocyte ratio (hazard ratio 9.150, p = 0.032) at baseline were significantly associated with a poor prognosis. CONCLUSIONS: Previous androgen receptor-axis-targeted therapy was the only risk factor for biochemical progression. Poor performance status, anemia, and high neutrophil-lymphocyte ratio were risk factors for poor prognosis in patients with metastatic castration-resistant prostate cancer treated with cabazitaxel. These risk factors seem useful for identifying patients with survival benefit from cabazitaxel treatment.

Impact of adherence to criteria on oncological outcomes of radical prostatectomy in patients opting for active surveillance: data from the PRIAS-JAPAN study.

OBJECTIVES: This study aimed to evaluate whether oncological outcomes of radical prostatectomy differ depending on adherence to the criteria in patients who opt for active surveillance. MATERIALS AND METHODS: We retrospectively reviewed the data of 1035 patients enrolled in a prospective cohort of the PRIAS-JAPAN study. After applying the exclusion criteria, 136 of 162 patients were analyzed. Triggers for radical prostatectomy due to pathological reclassification on repeat biopsy were defined as on-criteria. Off-criteria triggers were defined as those other than on-criteria triggers. Unfavorable pathology on radical prostatectomy was defined as pathological ≥T3, ≥GS 4 + 3 and pathological N positivity. We compared the pathological findings on radical prostatectomy and prostate-specific antigen recurrence-free survival between the two groups. The off-criteria group included 35 patients (25.7%), half of whom received radical prostatectomy within 35 months. RESULTS: There were significant differences in median prostate-specific antigen before radical prostatectomy between the on-criteria and off-criteria groups (6.1 vs. 8.3 ng/ml, P = 0.007). The percentage of unfavorable pathologies on radical prostatectomy was lower in the off-criteria group than that in the on-criteria group (40.6 vs. 31.4%); however, the differences were not statistically significant (P = 0.421). No significant difference in prostate-specific antigen recurrence-free survival was observed between the groups during the postoperative follow-up period (median: 36 months) (log-rank P = 0.828). CONCLUSIONS: Half of the off-criteria patients underwent radical prostatectomy within 3 years of beginning active surveillance, and their pathological findings were not worse than those of the on-criteria patients.

Clinical effect of rabbit anti-thymocyte globulin for chronic active antibody-mediated rejection after kidney transplantation.

Chronic active antibody-mediated rejection (CAAMR) is a frequent cause of late graft loss. However, effective treatment for CAAMR after kidney transplantation has not yet been established. Here, we present the case of a kidney transplant recipient who recovered from CAAMR after administration of rabbit anti-thymocyte globulin. A 61-year-old man underwent ABO-compatible living-donor kidney transplantation for end-stage kidney disease; the kidney was donated by his wife. Five years after the transplant, the patient's serum creatinine level and urine protein-to-creatinine ratio increased. He was subsequently diagnosed with CAAMR based on the kidney allograft biopsy and the presence of donor-specific human leukocyte antigen antibodies. Rabbit anti-thymocyte globulin treatment was administered following steroid pulse therapy. Subsequently, his serum creatinine levels and urine protein to creatinine ratio improved. There was also an improvement in the pathological findings seen on biopsy and the mean fluorescence intensity of donor-specific antibodies. In conclusion, this report describes the case of a kidney transplant recipient who developed CAAMR, treated using rabbit anti-thymocyte globulin. This strategy might be a viable treatment option for CAAMR after a kidney transplant.

Deferred radical prostatectomy in patients who initially elected for active surveillance: a multi-institutional, prospective, observational cohort of the PRIAS-JAPAN study.

BACKGROUND: This study aimed to evaluate the pathological findings and oncological outcomes of deferred radical prostatectomy in patients who initially elected for active surveillance in a Japanese cohort. METHODS: We retrospectively analyzed data collected from a multi-institutional prospective observational cohort of the Prostate Cancer Research International: Active Surveillance-JAPAN study between January 2010 and September 2020. Triggers for radical prostatectomy were disease progression based on pathological findings of repeat biopsy and patients' request. The primary end point was evaluation of prostate-specific antigen recurrence-free survival. Secondary end points were overall survival and comparison of pathological and oncological outcomes between patients stratified into immediate or late radical prostatectomy group by time to radical prostatectomy. RESULTS: Overall, 162 patients (15.7%) with prostate cancer underwent initial active surveillance followed by radical prostatectomy. The median time to radical prostatectomy was 18 months (interquartile range 14-43.3), and the median postoperative follow-up was 32 months (interquartile range 14-57.5). Prostate-specific antigen recurrence was observed in eight patients (4.9%). The 3-year prostate-specific antigen recurrence-free survival rate was 96.9%. The 5-year overall survival rate was 100%; however, one patient died of another cause. There were no significant differences in pathological findings between immediate and late radical prostatectomy groups. No significant difference in prostate-specific antigen recurrence-free survival was found between the two groups (log-rank p = 0.34). CONCLUSIONS: Radical prostatectomy after active surveillance, as an initial treatment option, does not lead to loss of curative chances in Japanese patients with early-stage prostate cancer in the short follow-up period.

[Robot-Assisted Partial Nephrectomy for Renal Cell Carcinoma Complicated by Leriche Syndrome : A Case Report].

A 71-year-old man was referred to our hospital for treatment of a 2 cm-sized right renal mass incidentally found by computed tomography (CT) and was diagnosed with right renal cell carcinoma cT1aN0M0. Contrast-enhanced CT revealed that the aorta was completely occluded below the inferior mesenteric artery origin, and Leriche syndrome was diagnosed. CT angiography showed several collateral arteries along the abdominal wall. A robot-assisted laparoscopic partial nephrectomy was performed to treat renal cell carcinoma. Preoperatively, we marked the collateral arteries using ultrasonography to avoid injury during trocar insertion. We did not observe any decrease in blood flow in the right leg during the operation. The pathological diagnosis was clear cell renal cell carcinoma. Leriche syndrome is a chronic occlusive disease involving the infrarenal aorta and the iliac arteries. Since lower limb blood flow is dependent on collateral circulation, it is important to avoid injuring the collateral arteries during surgery.

Real-world Outcomes of Tyrosine Kinase Inhibitors Immediately After Immune Checkpoint Inhibitors in Renal Cell Carcinoma.

BACKGROUND/AIM: Immune checkpoint inhibitors (ICIs) have demonstrated a survival benefit for patients with cancer. However, the clinical outcomes of subsequent tyrosine kinase inhibitors (TKIs) after ICI failure in patients with metastatic renal cell carcinoma (mRCC) remain unclear. PATIENTS AND METHODS: We retrospectively examined 38 patients with mRCC who started TKIs immediately after nivolumab with (combination group) or without ipilimumab (nivolumab group) between September 2016 and July 2019. RESULTS: Of the 38 patients, 16 and 11 achieved partial response and stable disease, respectively, resulting in a 42.1% objective response rate and 71.1% disease control rate. The median progression-free survival (PFS) from TKI initiation was 8.8 and 12.9 months in the nivolumab and combination groups, respectively. PFS and overall survival were significantly longer in patients with long-term responses to previous ICI treatment (p=0.0152 and p=0.0155, respectively). CONCLUSION: TKIs demonstrate adequate anti-tumour activity after treatment with ICIs in real-world settings.

The gut microbiota associated with high-Gleason prostate cancer.

We have found that intestinal bacteria and their metabolites, short-chain fatty acids (SCFAs), promote cancer growth in prostate cancer (PCa) mouse models. To clarify the association between gut microbiota and PCa in humans, we analyzed the gut microbiota profiles of men with suspected PCa. One hundred and fifty-two Japanese men undergoing prostate biopsies (96 with cancer and 56 without cancer) were included in the study and randomly divided into two cohorts: a discovery cohort (114 samples) and a test cohort (38 samples). The gut microbiota was compared between two groups, a high-risk group (men with Grade group 2 or higher PCa) and a negative + low-risk group (men with negative biopsy or Grade group 1 PCa), using 16S rRNA gene sequencing. The relative abundances of Rikenellaceae, Alistipes, and Lachnospira, all SCFA-producing bacteria, were significantly increased in high-risk group. In receiver operating characteristic curve analysis, the index calculated from the abundance of 18 bacterial genera which were selected by least absolute shrinkage and selection operator regression detected high-risk PCa in the discovery cohort with higher accuracy than the prostate specific antigen test (area under the curve [AUC] = 0.85 vs 0.74). Validation of the index in the test cohort showed similar results (AUC = 0.81 vs 0.67). The specific bacterial taxa were associated with high-risk PCa. The gut microbiota profile could be a novel useful marker for the detection of high-risk PCa and could contribute to the carcinogenesis of PCa.

[A Case of Bilateral Ureteral Stenosis Treated by Upper Urinary Tract Reconstruction Using an Ileal Ureter].

A 41-year-old female who suffered local recurrence of cervical cancer after receiving chemoradiotherapy underwent radical hysterectomy, radical vaginal resection, and pelvic and paraaortic lymph node dissection. After surgery, bilateral hydronephrosis due to right ureteral stenosis and left uretero-vaginal fistula occurred. We therefore placed a bilateral ureteral stent. Thereafter, we continued to replace the bilateral ureteral stent once every 3 months, but the replacement of the right ureteral stent became impossible three years after the initial placement. We thus performed bilateral upper urinary tract reconstruction using an ileal ureter with the aim of both eliminating the left ureteral vaginal fistula and resolving the right ureteral stricture.

The prognostic impact of immune-related adverse events in metastatic renal cell carcinoma patients treated with nivolumab: a real-world multi-institutional retrospective study.

BACKGROUND: Recent studies have shown that immune-related adverse events (irAEs) caused by immune checkpoint inhibitors (ICIs) were correlated with favorable clinical outcome in patients with melanoma. However, in metastatic renal cell carcinoma (mRCC) patients, there have been few reports about the correlation between irAEs and clinical efficacy of anti-programmed cell death protein-1 (PD-1) therapy. METHODS: We retrospectively investigated 160 mRCC patients who started nivolumab monotherapy between September 2016 and July 2019. IrAEs were defined as patients' AEs having a potential immunological basis that required close follow-up, or immunosuppressive therapy. We compared the data of patients who received nivolumab into two groups based on the occurrence of irAEs and assessed clinical efficacy in both groups. RESULTS: Of all mRCC patients, 47 patients (29.4%) developed irAEs. In patients who developed irAEs, the objective response rate and disease control rate were 38.8% and 77.6%, which were significantly higher when compared to that in patients without irAEs (p = 0.012 and p < 0.001, respectively). Furthermore, the incidence of irAEs was significantly associated with an increase in progression-free survival (PFS) [Hazard ratio (HR) = 0.4867; p = 0.0006] and overall survival (OS) (HR = 0.526; p = 0.0252). Importantly, PFS and OS seemed to be similar in patients who discontinued treatment because of irAEs and in those who did not discontinue because of irAEs (p = 0.36 and p = 0.35, respectively). CONCLUSION: Development of irAEs strongly correlates with clinical benefit for mRCC patients receiving nivolumab monotherapy in real-world settings.

[Robotic Surgery Can Complete Radical Surgery and Urinary Tract Reconstruction for Locally Advanced Rectal Cancer with Ureteral Invasion-A Case Report].

A 82-year-old man presented with diarrhea and fatigue. He had no past medical or surgical history except chronic renal failure. Locally advanced rectal cancer with invasion to left ureter was detected in computed tomography. Colonoscopy revealed a circular lesion 12 cm from the anal verge. Biopsy showed moderately differentiated adenocarcinoma. There was no sign of distal metastasis and we decided to conduct radical surgery. Robot-assisted laparoscopic lower anterior resection with partial resection of left ureter, and diverting ileostomy were carried out. Besides, urinary tract reconstruction of ureterocystoneostomy using Lich-Gregoir technique was conducted by urologists also with robot assistance. The pathological stage of the disease was pT4b(left ureter)N1bM0, pStage Ⅲc. The resection margin was secured and radical surgery was achieved. The patient was discharged on postoperative day 22nd without postoperative complication. He is alive without recurrence at 6 months after the operation.

[Rituximab Chemotherapy for Primary Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma of the Urinary Bladder : A Case Report].

An 84-year-old man consulted a local physician for asymptomatic macrohematuria. Abdominal ultrasonography revealed thickening ofthe bladder wall from the triangular part ofthe bladder to the posterior wall, and he was referred to our department. Cystoscopy showed extensive bladder wall thickening with edema ofthe mucosa. Abdominal contrast-enhanced computed tomography (CT) showed extensive bladder wall thickening and right external iliac lymphadenopathy accompanied by a contrast effect suspected ofbeing extravesical invasion. We performed transurethral resection ofthe bladder tumor and made the diagnosis ofmucosa associated lymphoid tissue (MALT) lymphoma. Our diagnosis made from positron emission tomography-CT performed after surgery was primary MALT lymphoma of the bladder and metastasis to the right external iliac lymph node. We administered rituximab 375 mg/m2 once a week for four times in total. CT after rituximab administration showed that the tumor and right external iliac lymph nodes had shrunk significantly, and no recurrence was present at 18 months after treatment.

[Primary Ureteral Small Cell Carcinoma with Multiple Recurrences and Metastases in the Early Postoperative Period : A Case Report].

A 79-year-old woman who presented with right hydronephrosis was referred to our hospital. Abdominal computed tomography (CT) showed a right ureteral tumor (cT3N0M0). Right nephroureterectomy and partial cystectomy were performed. Pathological examination revealed small cell carcinoma (mixed type ; INFb, pT3, ly1, v1, u-rt0, ur0, RM0). Cystoscopy showed intravesical recurrence of the tumor 3 months after the surgery. Transurethral resection was performed, and histopathological examination revealed small cell carcinoma (pT2). We recommended postoperative chemotherapy ; however, the patient and her family refused consent for chemotherapy. Liver and lymph node metastases developed, and the patient died 2 months after the transurethral resection.

NANOG helps cancer cells escape NK cell attack by downregulating ICAM1 during tumorigenesis.

BACKGROUND: At the beginning of tumorigenesis, newly born cancer cells must successfully avoid attack by the immune system. Although most abnormal cells are efficiently identified and destroyed by the immune system, particularly by NK cells, the molecular mechanisms by which newly born cancer cells evade NK cell surveillance are not fully understood. METHODS: NK cell resistance of highly tumorigenic population of human prostate cancer (PCa) cells were confirmed by xenograft in SCID mice with or without NK cell neutralization. The mechanisms by which the tumorigenic PCa cells evaded NK cell attack were investigated by RNAseq, ChIPseq, generation of several transformants and xenograft in SCID mice. RESULTS: Here, we show that PCa cells have a strengthened ability to escape NK cell attack due to NANOG, a pluripotent-related transcription factor, mediating the repression of ICAM1, a cell adhesion molecule, during tumorigenesis. Mechanistically, NANOG directly binds to the region upstream of ICAM1. As the binding between NANOG and the upstream ICAM1 region increases, p300 binding to this region is diminished, resulting in decreased ICAM1 expression. High NANOG expression confers PCa cells the ability to resist NK cell attack via the repression of ICAM1. Consistent with these results, low ICAM1 expression is significantly correlated with a high recurrence rate in patients with PCa. CONCLUSIONS: Our findings indicate that repression of ICAM1 is a critical mechanism by which cancer cells evade attack from NK cells during tumorigenesis. These results suggest a pivotal role of NANOG in establishing a gene expression profile for escaping the immune system.

[A Case of Pericardial Effusion Induced by Nivolumab for Metastatic Renal Cell Carcinoma].

A 72-year-old female with left renal cell carcinoma and lymphadenopathy had undergone hand-assisted laparoscopic left nephrectomy and dissection of the lymph node (papillary renal cell carcinoma, type 2, pT3a pN2 M1). She had been treated with adjuvant chemotherapy with sunitinib, temsirolimus and pazopanib. However, the patient was started on nivolumab due to disease progression. After receiving 5 cycles of nivolumab, she was admitted to our emergency room for chest discomfort and appetite loss. Since computed tomographic (CT) scan showed pericardial effusion, we performed pericardiocentesis. Cytological examination of the pericardial effusion demonstrated leukocytes and no malignant cells. CT scan two weeks after cardiocentesis showed no recurrent pericardial effusion. She became stable with nivolumab, but the administration of nivolumab was discontinued and she started receiving axitinib.