Effect of music on colonoscopy performance: A propensity score-matched analysis.

BACKGROUND: Music has been used to reduce stress and improve task performance during medical therapy. AIM: To assess the effects of music on colonoscopy performance outcomes. METHODS: We retrospectively reviewed patients who underwent colonoscopy performed by four endoscopists with popular music. Colonoscopy performance outcomes, such as insertion time, adenoma detection rate (ADR), and polyp detection rate (PDR), were compared between the music and non-music groups. To reduce selection bias, propensity score matching was used. RESULTS: After one-to-one propensity score matching, 169 colonoscopies were selected from each group. No significant differences in insertion time (4.97 vs 5.17 min, P = 0.795) and ADR (39.1% vs 46.2%, P = 0.226) were found between the two groups. Subgroup analysis showed that the insertion time (3.6 vs 3.8 min, P = 0.852) and ADR (51.1% vs 44.7%, P = 0.488) did not significantly differ between the two groups in experts. However, in trainees, PDR (46.9% vs 66.7%, P = 0.016) and ADR (25.9% vs 47.6%, P = 0.006) were significantly lower in the music than in the non-music group. CONCLUSION: The current study found that listening to music during colonoscopy did not affect procedure performance. Moreover, it suggested that music may distract trainees from appropriately detecting adenomas and polyps.

Outcomes in Patients with Pulmonary Arterial Hypertension Underwent Transcatheter Closure of an Atrial Septal Defect.

Pulmonary arterial hypertension (PAH) related to an atrial septal defect (ASD) poses a challenge to transcatheter closure of an ASD (tcASD). We aimed to determine the predictors for remaining PAH (rPAH) post-tcASD. This retrospective study was conducted at a single tertiary university hospital. Adult patients with an ASD and PAH were divided into three groups according to pulmonary vascular resistance (PVR). Normalization of pulmonary atrial systolic pressure (PASP) was defined as an estimated right ventricular systolic pressure < 40 mmHg and was determined using transthoracic echocardiography. Among 119 patients, 80% showed PAH normalization post-tcASD. Normalization of PAH post-tcASD was observed in 100%, 56.2%, and 28.6% of patients in mild, moderate, and severe PVR groups, respectively. The patients' New York Heart Association functional class improved. Multivariate logistic regression analysis showed that age and high PVR were significant risk factors for rPAH. A receiving operator curve analysis showed a PASP cutoff value > 67.5 mmHg to be predictive of rPAH post-tcASD, with an area under the curve value of 0.944 (sensitivity, 0.922; specificity 0.933). Most patients, including moderate-to-severe PAH patients, improved hemodynamically and clinically with tcASD. Since patients with severe PAH are at a risk of rPAH, tcASD should be performed by selecting the patient carefully based on pre-procedure medication, a vasoreactivity test, and a balloon occlusion test.

Relationship between the High Fatty Liver Index and Risk of Fracture.

Background/Aims: The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased rapidly as a consequence of more sedentary lifestyles and a Westernized diet. Fracture is a major clinical problem in older people, but few large-scale cohort studies have evaluated the relationship between NAFLD and fracture. Therefore, we aimed to determine whether the fatty liver index (FLI), which represents the severity of NAFLD, can predict fracture risk. Methods: We analyzed the relationship between the FLI and incident fracture using multivariate Cox proportional hazards models and data for 180,519 individuals who underwent National Health check-ups in the Republic of Korea between 2009 and 2014. Results: A total of 2,720 participants (1.5%) were newly diagnosed with fracture during the study period (median 4.6 years). The participants were grouped according to FLI quartiles (Q1, 0 to <5.653; Q2, 5.653 to <15.245; Q3, 15.245 to <37.199; and Q4 ≥37.199). The cumulative fracture incidence was significantly higher in the highest FLI group than in the lowest FLI group (Q4, 986 [2.2%] and Q1, 323 [0.7%]; p<0.001). The adjusted hazard ratio indicated that the highest FLI group was independently associated with a higher incidence of fracture (hazard ratio for Q4 vs Q1, 2.956; 95% confidence interval, 2.606 to 3.351; p<0.001). FLI was significantly associated with a higher incidence of fracture, independent of the baseline characteristics of the participants. Conclusions: Our data imply that the higher the FLI of a Korean patient is, the higher their risk of osteoporotic fracture, independent of key confounding factors. (Gut Liver, Published online July 27, 2022).

Efficacy of a Restrictive Diet in Irritable Bowel Syndrome: A Systematic Review and Network Meta-analysis.

Background/Aims: Dietary factors can aggravate the symptoms of irritable bowel syndrome (IBS). Many IBS patients try restrictive diets to relieve their symptoms, but the types of diets with an exacerbating factor are unknown. Therefore, this paper reports the results of a systematic review and network meta-analysis of randomized-controlled trials (RCTs) reviewing the efficacy of food restriction diets in IBS. Methods: The MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Clinicaltrials.gov databases were searched until July 21, 2021, to retrieve RCTs assessing the efficacy of restriction diets in adults with IBS. Two independent reviewers performed the eligibility assessment and data abstraction. RCTs that evaluated a restriction diet versus a control diet and assessed the improvement in global IBS symptoms were included. These trials reported a dichotomous assessment of the overall response to therapy. Results: A total of 1,949 citations were identified. After full-text screening, 14 RCTs were considered eligible for the systematic review and network meta-analysis. A starch- and sucrose-reduced diet and a diet with low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) showed significantly better results than a usual diet. Symptom flare-ups in patients on a gluten- free diet were also significantly lower than in those on high-gluten diets. Conclusions: These findings showed that the starch- and sucrose-reduced, low FODMAP, and gluten-free diets had superior effects in reducing IBS symptoms. Further studies, including head-to-head trials will be needed to establish the effectiveness of dietary restrictions on IBS symptoms.

An Enhanced Tree Routing Based on Reinforcement Learning in Wireless Sensor Networks.

In wireless sensor networks, tree-based routing can achieve a low control overhead and high responsiveness by eliminating the path search and avoiding the use of extensive broadcast messages. However, existing approaches face difficulty in finding an optimal parent node, owing to conflicting performance metrics such as reliability, latency, and energy efficiency. To strike a balance between these multiple objectives, in this paper, we revisit a classic problem of finding an optimal parent node in a tree topology. Our key idea is to find the best parent node by utilizing empirical data about the network obtained through Q-learning. Specifically, we define a state space, action set, and reward function using multiple cognitive metrics, and then find the best parent node through trial and error. Simulation results demonstrate that the proposed solution can achieve better performance regarding end-to-end delay, packet delivery ratio, and energy consumption compared with existing approaches.

The Specific Gravity-Free Method for the Isolation of Circulating Tumor KRAS Mutant DNA and Exosome in Colorectal Cancer.

BACKGROUND: Circulating tumor DNA (ctDNA) and exosome have been widely researched in the field of medical technology and diagnosis platforms. The purpose of our study was to improve the capturing properties of ctDNA and exosome, which involved combining two beads using approaches that may provide a new method for cancer diagnoses. METHODS: We present a dual isolation system including a polydopamine (PDA)-silica-coated alginate bead for circulating tumor DNA (ctDNA) capture and an anti-CD63 immobilized bead for exosome capture. We examined the ctDNA mutation in pre-operative plasma samples obtained from 91 colorectal cancer (CRC) patients using a droplet digital PCR (ddPCR). RESULTS: The area under the curve (AUROC) of ctKRAS G12D mutation in the buffy coat was 0.718 (95% CI: 0.598-0.838; p = 0.001). Patients with CRC that had unmethylation of MLH1 and MSH2 showed significantly higher buffy coat ctKRAS G12D mutations, ascites ctKRAS G12D mutations, miR-31-5, and mixed scores than the patients with a methylation of MLH1 and MSH2. CONCLUSION: Our proposed alginate bead using the specific gravity-free method suggests that the screening of mutated ctKRAS DNA and miR-31-5 by liquid biopsy aids in identifying the patients, predicting a primary tumor, and monitoring in the early detection of a tumor.

Use of 3D Human Liver Organoids to Predict Drug-Induced Phospholipidosis.

Drug-induced phospholipidosis (PL) is a storage disorder caused by the formation of phospholipid-drug complexes in lysosomes. Because of the diversity of PL between species, human cell-based assays have been used to predict drug-induced PL in humans. We established three-dimensional (3D) human liver organoids as described previously and investigated their liver characteristics through multiple analyses. Drug-induced PL was initiated in these organoids and in monolayer HepG2 cultures, and cellular changes were systemically examined. Organoids that underwent differentiation showed characteristics of hepatocytes rather than HepG2 cells. The organoids also survived under PL-inducing drug conditions for 48 h and maintained a more stable albumin secretion level than the HepG2 cells. More cytoplasmic vacuoles were observed in organoids and HepG2 cells treated with more potent PL-induced drugs, but to a greater extent in organoids than in HepG2 cells. Lysosome-associated membrane protein 2, a marker of lysosome membranes, showed a stronger immunohistochemical signal in the organoids. PL-distinctive lamellar bodies were observed only in amiodarone-treated organoids by transmission electron microscopy. Human liver organoids are thus more sensitive to drug-induced PL and less affected by cytotoxicity than HepG2 cells. Since PL is a chronic condition, these results indicate that organoids better reflect metabolite-mediated hepatotoxicity in vivo and could be a valuable system for evaluating the phospholipidogenic effects of different compounds during drug development.

Epithelioid sarcoma associated with neurofibromatosis type I.

In general, patients with neurofibromatosis type I have a higher risk than those with other types of neurofibromatosis of developing soft-tissue sarcomas related to the nervous system. We here present a 42-year-old man with neurofibromatosis type I who developed a protruding mass over only 2 weeks. The histopathological diagnosis was epithelioid sarcoma. Epithelioid sarcomas are rare and, to the best of our knowledge, no epithelioid sarcomas have been reported in patients with neurofibromatosis type I. Radical excision of the primary lesion was performed and postoperative radiotherapy and chemotherapy administered, as is recommended for epithelioid sarcoma. Our case emphasizes that patients with neurofibromatosis type I may develop malignant tumors.

ABL001, a Bispecific Antibody Targeting VEGF and DLL4, with Chemotherapy, Synergistically Inhibits Tumor Progression in Xenograft Models.

Delta-like-ligand 4 (DLL4) is a promising target to augment the effects of VEGF inhibitors. A simultaneous blockade of VEGF/VEGFR and DLL4/Notch signaling pathways leads to more potent anti-cancer effects by synergistic anti-angiogenic mechanisms in xenograft models. A bispecific antibody targeting VEGF and DLL4 (ABL001/NOV1501/TR009) demonstrates more potent in vitro and in vivo biological activity compared to VEGF or DLL4 targeting monoclonal antibodies alone and is currently being evaluated in a phase 1 clinical study of heavy chemotherapy or targeted therapy pre-treated cancer patients (ClinicalTrials.gov Identifier: NCT03292783). However, the effects of a combination of ABL001 and chemotherapy on tumor vessels and tumors are not known. Hence, the effects of ABL001, with or without paclitaxel and irinotecan were evaluated in human gastric or colon cancer xenograft models. The combination treatment synergistically inhibited tumor progression compared to each monotherapy. More tumor vessel regression and apoptotic tumor cell induction were observed in tumors treated with the combination therapy, which might be due to tumor vessel normalization. Overall, these findings suggest that the combination therapy of ABL001 with paclitaxel or irinotecan would be a better clinical strategy for the treatment of cancer patients.

Subretinal transplantation of human embryonic stem cell-derived retinal pigment epithelium (MA09-hRPE): A safety and tolerability evaluation in minipigs.

This study aimed to determine the safety and tolerability of the subretinal injection of hESC-derived RPE cells at higher doses than the established clinical dose (5 × 104 cells/150 µL) by using minipigs. The hESC-derived RPE cells (60 or 120 × 104 cells/150 µL) were injected in subretinal region, and minipigs were sacrificed at Weeks 4, 8, and 12 post-surgery. Time-course examination was performed by using fundus photography, optical coherence tomography (OCT), histopathology, and fluorescence in situ hybridization (FISH). After surgery, retinal bleb and pigmentation were seen and retinal bleb became smaller gradually. In histopathology, cell clusters consisting of a uniform population of the round to oval cells were seen at the subretinal injection site. In immunohistochemistry, most of the cells were positive for anti-CD3 and CD45 antibodies but negative for anti-human nuclei antibody; transplanted cells were not detectable by DNA probe in FISH assay. Cell clusters were thought to be a host immune response to trauma or transplanted cells. There were no other changes related to subretinal RPE cell injection. These results suggested that subretinal injection of hESC-derived RPE cells (60 and 120 × 104 cells/150 µL) in minipigs is well-tolerated and safe.

Malignant melanoma on a thermal burn scar.

Chronic burn scars often cause various skin malignancies at rates of up to 2%. These lesions are usually squamous cell carcinomas, but rarely, malignant melanoma is reported. We report a 67-year-old male with a malignant melanoma on a burn scar with regional metastasis. This patient presented an ulcerative lesion only in 2 weeks. After histopathological diagnosis, we performed only palliative surgery on patient's demand, and followed up the subsequent deterioration course. Our case reemphasizes the need for rapid diagnosis and treatment when suspect lesions are present on chronic burn scar. Also, physician should be in mind and inform the patient about malignant melanoma and its aggressive course.

Evaluation of Circulating MicroRNA Biomarkers in the Acute Pancreatic Injury Dog Model.

This study aimed to evaluate the usefulness of four microRNAs (miRNAs) in an acute pancreatic injury dog model. Acute pancreatitis was induced by infusion of cerulein for 2 h (7.5 µg/kg/h). The levels of well-known miRNAs, microRNA-216a (miR-216a) and microRNA-375 (miR-375), and new candidates microRNA-551b (miR-551b), and microRNA-7 (miR-7), were measured at 0, 0.5, 1, 2, 6, 12, and 24 h with serum amylase and lipase, and histopathological examination was performed. Among the four miRNAs, miR-216a and miR-375, and serum enzymes were significantly increased by cerulein treatment. The expression levels of miRNAs and serum enzymes peaked at 2⁻6 h with a similar pattern; however, the overall increases in miR-216a and miR-375 levels were much higher than those of the serum enzyme biomarkers. Increased levels of miR-216a and miR-375 were most highly correlated to the degree of individual histopathological injuries of the pancreas, and showed much greater dynamic response than serum enzyme biomarkers. Twenty-four-hour time-course analysis in this study revealed time-dependent changes of miRNA expression levels, from initial increase to decrease by predose level in acute pancreatitis. Our findings demonstrate that, in dogs, miR-216a and miR-375 have the potential to sensitively detect pancreatitis and reflect well the degree of pancreatic injury, whereas miR-551b and miR-7 do not.

Nasal Elongation with Septal Half Extension Graft: Modification of Conventional Septal Extension Graft Using Minimal Septal Cartilage.

BACKGROUND: In Asian rhinoplasty, a septal extension graft can be used for both tip projection and derotation of the alar cartilage. However, patients often do not have enough harvestable septal cartilage to create the septal extension graft. We therefore devised a method with which to fix the derotated alar cartilage with a small amount of septal cartilage. METHODS: From January 2012 to December 2016, 23 patients underwent short nose correction with a septal half extension graft made of septal cartilage and were postoperatively monitored for at least 6 months. The alar cartilage was completely separated from the adjacent structures, especially the scroll area and hinge complex, for caudal derotation. The septal half extension graft was then harvested from the septal cartilage and secured to the caudal septum and the lateral crura of the alar cartilage. Photographs of the patients were compared immediately before surgery and 1 year after surgery. RESULTS: Of the 23 patients, 21 (91%) had satisfactory results without short nose recurrence. Two (9%) patients developed recurrence: undercorrection and poor tip projection in one patient each. Aesthetic assessment of short nose correction was performed by comparing the columellar labial angle before and after surgery. Our method reduced the columellar labial angle by 6.2% (paired t test, p < 0.05, t = 31.698). CONCLUSION: In patients who cannot undergo conventional septal extension graft due to insufficient amounts of septal cartilage, the septal half extension graft could be a promising alternative technique for short nose correction with minimal septal cartilage harvesting. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Development of a Mouse Model of Prostate Cancer Using the Sleeping Beauty Transposon and Electroporation.

The Sleeping Beauty (SB) transposon system is non-viral and uses insertional mutagenesis, resulting in the permanent expression of transferred genes. Although the SB transposon is a useful method for establishing a mouse tumor model, there has been difficulty in using this method to generate tumors in the prostate. In the present study, electroporation was used to enhance the transfection efficiency of the SB transposon. To generate tumors, three constructs (a c-Myc expression cassette, a HRAS (HRas proto-oncogene, GTPase) expression cassette and a shRNA against p53) contained within the SB transposon plasmids were directly injected into the prostate. Electroporation was conducted on the injection site after the injection of the DNA plasmid. Following the tumorigenesis, the tumors were monitored by animal PET imaging and identified by gross observation. After this, the tumors were characterized by using histological and immunohistochemical techniques. The expression of the targeted genes was analyzed by Real-Time qRT-PCR. All mice subjected to the injection were found to have prostate tumors, which was supported by PSA immunohistochemistry. To our knowledge, this is the first demonstration of tumor induction in the mouse prostate using the electroporation-enhanced SB transposon system in combination with c-Myc, HRAS and p53. This model serves as a valuable resource for the future development of SB-induced mouse models of cancer.

Validation of the Child Post-Traumatic Cognitions Inventory in Korean survivors of sexual violence.

BACKGROUND: Dysfunctional cognitions related to trauma is an important factor in the development and maintenance of post-traumatic stress disorder symptoms in children and adolescents. The Child Post-traumatic Cognitions Inventory (CPTCI) assesses such cognitions about trauma. We investigated the psychometric properties of the Korean version of CPTCI and its short form by surveying child and adolescent survivors of sexual violence. METHODS: Children and adolescents aged 7-16 years (N = 237, Mage = 12.6, SD = 2.3, 222 [93.7%] were female) who were exposed to sexual violence were included in this survey. We assessed the factor structure, internal consistency, and validity of the CPTCI and its short form through data analysis. RESULTS: Confirmatory factor analysis results supported the two-factor model presented in the original study. The total scale, its subscales, and the short form had good internal consistency (Cronbach's α = .96 for total scale and .91-.95 for the other scales). The CPTCI showed high correlations with scales measuring post-traumatic stress symptoms (r = .77-.80), anxiety (r = .69-.71), and depression (r = .74-.77); the correlation with post-traumatic stress symptoms was the highest. The differences in CPTCI scores per post-traumatic stress symptom levels were significant (all p < .001) Sex differences in CPTCI scores were not significant (p > .05 for all comparisons); however, the scores exhibited differences per age group (all p < .001). CONCLUSIONS: The results indicate that the Korean version of the CPTCI is a valid and reliable scale; therefore, it may be a valuable tool for assessing maladaptive cognitions related to trauma in research and clinical settings.

Efficacy of HL036 versus Cyclosporine A in the Treatment of Naturally Occurring Canine Keratoconjunctivitis Sicca.

PURPOSES: To (i) evaluate the efficacy and safety of HL036, a tumor-necrosis factor (TNF)-α-blocking protein, in the treatment of naturally occurring canine keratoconjunctivitis sicca (KCS) and (ii) compare these features with those of 1% cyclosporine A (CsA). MATERIALS AND METHODS: Dogs (n = 29) diagnosed with KCS were randomly assigned to receive one drop topical aqueous HL036 (0.2, 1, or 5 mg/mL) or 1% CsA in the affected eye(s) at 12-h intervals for 42 days. Schirmer's tear test (STT), fluorescein corneal staining (FCS), and clinical-sign scores were evaluated prior to application (day-0) and on days 14, 28, and 42 post-treatment. Of the 29 dogs enrolled, 19 (65.5%) received HL036 (HL036 group) and 10 (34.5%) received 1% CsA (CsA group). A linear mixed-effects model analysis was performed to determine score differences between groups and over time. RESULTS: After treatment, clinical-sign scores and STT values had significantly improved compared with baseline levels in dogs of both treatment groups. Decreases in total clinical-sign scores for the HL036-group were greater than those of 1% CsA group. No severe adverse reactions were noted in either group. CONCLUSIONS: Our findings suggest that topical aqueous HL036 is well-tolerated and more effective than 1% CsA for treating naturally occurring canine KCS.

EZH2 Expression in Naturally Occurring Canine Tumors.

Enhancer of zeste homolog 2 (EZH2) shows upregulated expression in tumors and is an important driver of tumor development and progression. However, the mechanism underlying the mediation of tumor aggressiveness by EZH2 remains unclear. We here investigated the levels of EZH2 in various normal and tumorous dog tissues and compared these patterns with those of the corresponding human tissues. Immunohistochemical analysis showed positive staining for EZH2 in 76 of 82 cases of canine tumors, whereas low or negligible staining occurred in normal tissues and other canine tumors, including hepatocellular adenoma and lipoma. In particular, canine lymphoma, melanoma, basal cell tumors, squamous cell carcinoma, and prostate cancer all show EZH2 overexpression, as do their human counterparts. Given the similarities of spontaneous canine tumors to human cancers, we believe that these canine tumors can be used as animal models in future research and clinical trials in the development of EZH2 inhibitors.

Program of Integrated Care for Patients with Chronic Obstructive Pulmonary Disease and Multiple Comorbidities (PIC COPD+): a randomised controlled trial.

We sought to evaluate the effectiveness of a multi-component, case manager-led exacerbation prevention/management model for reducing emergency department visits. Secondary outcomes included hospitalisation, mortality, health-related quality of life, chronic obstructive pulmonary disease (COPD) severity, COPD self-efficacy, anxiety and depression.Two-centre randomised controlled trial recruiting patients with ≥2 prognostically important COPD-associated comorbidities. We compared our multi-component intervention including individualised care/action plans and telephone consults (12-weekly then 9-monthly) with usual care (both groups). We used zero-inflated Poisson models to examine emergency department visits and hospitalisation; Cox proportional hazard model for mortality.We randomised 470 participants (236 intervention, 234 control). There were no differences in number of emergency department visits or hospital admissions between groups. We detected difference in emergency department visit risk, for those that visited the emergency department, favouring the intervention (RR 0.74, 95% CI 0.63-0.86). Similarly, risk of hospital admission was lower in the intervention group for those requiring hospital admission (RR 0.69, 95% CI 0.54-0.88). Fewer intervention patients died (21 versus 36) (HR 0.56, 95% CI 0.32-0.95). No differences were detected in other secondary outcomes.Our multi-component, case manager-led exacerbation prevention/management model resulted in no difference in emergency department visits, hospital admissions and other secondary outcomes. Estimated risk of death (intervention) was nearly half that of the control.

New anthropometric data for preoperative planning in orbital wall fracture treatment: the use of eyelid drooping.

BACKGROUND: The presence of enophthalmos is an important determinant in the decision of orbital wall fracture surgery. We proposed eyelid drooping as a new anthropometric diagnostic measure and analyzed whether eyelid drooping is associated with enophthalmos. METHODS: This retrospective study was performed from January 2014 to December 2016. A total of 75 patients with blowout fractures were studied. One experimenter measured the degree of enophthalmos using a Hertel exophthalmometer at 1 week after trauma and at 3 months after surgery. The height change of the upper eyelid was measured using the marginal reflex distance (MRD) on both sides, and the degree of eyelid drooping was calculated by comparing the two lengths. We analyzed statistically the correlation between enophthalmos and eyelid drooping. RESULTS: We found a highly significant correlation between the degree of enophthalmos and the reduction rate of MRD (RRM, as an indicator of eyelid drooping) at 1 week after trauma (r = 0.845). Approximately 2.0 mm of enophthalmos was associated with a 30.8% reduction in MRD on the affected side as compared with the normal side. At 3 months after surgery, patients showed improved eyelid appearance, with a moderate association between enophthalmos and RRM. CONCLUSION: We demonstrated that the degree of enophthalmos, measured using an exophthalmometer, is associated with a change in the height of the upper eyelid. Thus, upper eyelid drooping can be used as another indicator for orbital wall fracture surgery. Compared with conventional methods, measurements of eyelid drooping are easy to perform, offering a great advantage and understanding to the patient.

Renal oncocytoma in a cat with chronic renal failure.

CASE SUMMARY: A 9-year-old male neutered domestic shorthair cat presented with anorexia. Ultrasonography showed an irregularly shaped hypoechoic mass in the cranial pole of the right kidney. Ultrasound-guided fine-needle aspiration of the renal mass was performed. Cytology revealed moderate cellularity smears composed of epithelial cell clusters, which consisted of an exclusive population of oncocytic cells seen in sheets and papillary clusters along with abundant single cells. A moderate-to-abundant amount of densely stained granular cytoplasm with round nuclei and indistinct nucleoli was seen. The cytological diagnosis was renal oncocytic neoplasm. CT and surgical resection revealed a firm tan mass in the right kidney. A final diagnosis of renal oncocytoma was made on the basis of histology, immunohistochemical staining profile (positive for cytokeratin, and negative for chromogranin A, neuron-specific enolase and vimentin) of neoplastic cells, together with the electronic microscopy results. RELEVANCE AND NOVEL INFORMATION: We believe that this is the first report of the cytological features of feline renal oncocytoma.