Successful conservative treatment for massive tracheal necrosis after lung segmentectomy.

BACKGROUND: Tracheal necrosis, which is rare because the trachea has rich in blood supply, can be a serious condition. Herein, we report the case of extensive tracheal necrosis that developed after right apical segmentectomy for a metastatic lung tumor of esophageal cancer. CASE PRESENTATION: A 74-year-old man who had undergone thoracoscopic subtotal esophagectomy and gastric tube reconstruction via the posterior sternal route for esophageal adenocarcinoma 2 years previously was referred to our department with an enlarging nodal lesion in the right upper lung lobe. Computed tomography revealed a 30-mm tumor in the right apical segment with no lymph node enhancement, suggesting primary lung cancer or a metastatic lung tumor. The patient underwent right apical segmentectomy. The upper lobe was adherent to the chest wall and mediastinal fat from the apex of the lung to the dorsal side, with particularly strong adhesion at the esophagectomy site. After dissecting the adhesions, right apical segmentectomy was performed via complete video-assisted thoracic surgery. The patient was discharged on the 9th day after surgery without any complications. Pathologic findings revealed a metastatic lung tumor originating from the patient's esophageal cancer. On the 26th day after surgery, the patient returned with dyspnea and increased sputum. Computed tomography images revealed that the posterior wall of the trachea was missing an area of 16 × 42 mm and was connected to the dead space after the right apical segmentectomy, with no effusion. We diagnosed extensive tracheal necrosis. Considering that the patient's status was very well despite the extensive tracheal necrosis, we chose conservative treatment. After receiving 12 days of intravenous antibiotic treatment, his symptoms improved, and he was discharged on day 26 after admission. CONCLUSIONS: Right upper lung lobe resection after esophagectomy has a risk of tracheal necrosis. Conservative treatment is one approach to manage massive tracheal necrosis in patients with stable respiratory conditions.

Randomized phase II study of daily versus alternate-day administrations of S-1 for the elderly patients with completely resected pathological stage IA (tumor diameter > 2 cm)-IIIA of non-small cell lung cancer: Setouchi Lung Cancer Group Study 1201.

BACKGROUND: It is shown that the postoperative adjuvant chemotherapy for non-small cell lung cancer (NSCLC) was associated with survival benefit in an elderly population. We aimed to analyze the feasibility and efficacy of alternate-day S-1, an oral fluoropyrimidine, for adjuvant chemotherapy in elderly patients with completely resected pathological stage IA (tumor diameter > 2 cm) to IIIA (UICC TNM Classification of Malignant Tumours, 7th edition) NSCLC. METHODS: Elderly patients were randomly assigned to receive adjuvant chemotherapy for one year consisting of either alternate-day oral administration of S-1 (80 mg/m2/day) for 4 days a week (Arm A) or a daily oral administration of S-1 (80 mg/m2/day) for 14 consecutive days followed by 7-day rest (Arm B). The primary endpoint was feasibility (treatment completion rate), which was defined as the proportion of patients who completed the allocated intervention for 6 months with a relative dose intensity (RDI) of 70% or more. RESULTS: We enrolled 101 patients in which 97 patients received S-1 treatment. The treatment completion rate at 6 months was 69.4% in Arm A and 64.6% in Arm B (p = 0.67). Treatment completion rate in Arm B tended to be lower compared to Arm A, as the treatment period becomes longer (at 9 and 12 months). RDI of S-1 at 12 months and completion of S-1 administration without dose reduction or postponement at 12 months was significantly better in Arm A than in Arm B (p = 0.026 and p < 0.001, respectively). Among adverse events, anorexia, skin symptoms and lacrimation of any grade were significantly more frequent in Arm B compared with Arm A (p = 0.0036, 0.023 and 0.031, respectively). The 5-year recurrence-free survival rates were 56.9% and 65.7% for Arm A and B, respectively (p = 0.22). The 5-year overall survival rates were 68.6% and 82.0% for Arm A and B, respectively (p = 0.11). CONCLUSION: Although several adverse effects were less frequent in Arm A, both alternate-day and daily oral administrations of S-1 were demonstrated to be feasible in elderly patients with completely resected NSCLC. TRIAL REGISTRATION: Unique ID issued by UMIN: UMIN000007819 (Date of registration: Apr 25, 2012) https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000009128. Trial ID issued by jRCT: jRCTs061180089 (Date of registration: Mar 22, 2019, for a shift toward a "specified clinical trial" based on Clinical Trials Act in Japan) https://jrct.niph.go.jp/en-latest-detail/jRCTs061180089.

Risk factors for long-term decline in post-operative pulmonary function after lung resection.

OBJECTIVES: The study aimed to examine the risk factors for long-term decline in pulmonary function after anatomical resection for lung cancer and the effects of the decrease on survival. METHODS: We retrospectively examined 489 patients who underwent anatomical resection for lung cancer between 2010 and 2020. Pulmonary function tests were performed preoperatively and at 1, 3, 6 and 12 months after surgery. The lower interquartile medians of the reduction rates of forced expiratory volume in 1 s and vital capacity at 12 months after surgery were taken as the cut-off values of risk factors for the decrease in post-operative pulmonary function. RESULTS: Forced expiratory volume in 1 s and vital capacity decreased the most in the first month after surgery and then gradually recovered. Vital capacity continued to increase even after 6 months post-surgery, whereas forced expiratory volume in 1 s stabilized. Multivariable logistic analysis showed that the number of resected segments (odds ratio, 2.09; 95% confidence interval, 1.12-3.89; P = 0.019) was a risk factor for the decrease in forced expiratory volume in 1 s at 12 months, and the numbers of resected segments (odds ratio, 1.36; 95% confidence interval, 1.13-1.63; P < 0.001) and post-operative complications (odds ratio, 2.32; 95% confidence interval, 1.01-5.35; P = 0.047) were independent risk factors for decrease in vital capacity. Multivariate cox regression analysis showed that the decrease in vital capacity at 12 months was significantly associated with overall survival (hazard ratio, 2.02; 95% confidence interval, 1.24-3.67; P = 0.004). CONCLUSIONS: Long-term decrease in vital capacity, which was influenced by the number of resected segments and post-operative complications, adversely affected survival.

Histopathology and Cytology of Pulmonary Myoepithelial Neoplasms: 2 Cases.

Myoepithelial neoplasms (MNs) of the lung are extremely rare tumors. Approximately 40 cases of pulmonary MNs have been reported to date. Herein, we report extremely rare cases of different types of pulmonary MN, including cytological features. Case 1 is an 18-year-old female, and case 2 is a 73-year-old female patient. They presented to our hospital with nodules of the lung. Histological examination revealed tumor cells with round to oval nuclei and acidophilic cytoplasm that formed nests or fascicles with mild hyalinized stroma in case 1 and tumors containing the bi-phasic components of a nest-like and fascicle pattern with pleomorphism in case 2. Immunohistochemically, these tumors were positive for cytokeratin (CK) AE1/AE3, CK5/6, vimentin, calponin, and EMA, and focal positive for S-100a protein and alpha smooth muscle actin. The pathological diagnoses in cases 1 and 2 were myoepithelioma and myoepithelial carcinoma, respectively. In conclusion, we encountered two cases of extremely rare MNs that occurred in the lung. This disease can be diagnosed by collecting appropriate cytological and histological findings and should be listed as a differential diagnosis.

Classification based on skeletal muscle mass and the severity of lung emphysema impacts on clinical outcomes after anatomical resection for lung cancer.

OBJECTIVES: Both sarcopenia and lung emphysema are prognostic factors in lung cancer and can be easily assessed using the psoas muscle index and Goddard score, respectively. We investigated the clinical significance of the classification based on psoas muscle index and Goddard score in non-small cell lung cancer. METHODS: A total of 303 consecutive patients who underwent anatomical resection for non-small cell lung cancer were retrospectively analyzed. The psoas muscle at the level of the third lumbar vertebrae and Goddard score were measured on preoperative computed tomography. The psoas muscle was adjusted by height as the psoas muscle index (cm2/m2). We divided patients into three groups: low-, middle- and high-risk, using cut-off values of psoas muscle index < 6.36 cm2/m2 for males and 3.92 cm2/m2 for females and Goddard score higher than 7. The predictors of postoperative complications and prognosis were examined. RESULTS: High-, middle- and low-risk were present in 30 (10%), 164 (54%) and 109 (36%) patients, respectively. High risk was significantly associated with male sex, low pulmonary function, more comorbidities and increased postoperative complications. High-risk patients showed poorer overall survival than middle- and low-risk patients (P < 0.001). Multivariable analysis revealed that high risk was an independent risk factor for postoperative complications and unfavorable prognostic factors (P = 0.011, P = 0.014, respectively). CONCLUSIONS: Classification based on psoas muscle index and Goddard score is significantly associated with short- and long-term outcomes in patients with lung cancer. This method can be easily assessed for patients and may help select patients for nutritional support and rehabilitation before surgery.

Prognosis of resected non-small cell lung cancer with pleural plaques on intrathoracic findings.

BACKGROUND: The prognosis of patients with lung cancer who demonstrate pleural plaques intraoperatively, which may be associated with exposure to asbestos, is unclear. Here, we compared the clinicopathological characteristics and prognosis of these patients to those of patients without pleural plaques. METHODS: We included patients who underwent curative-intent resection for non-small cell lung cancer. We retrospectively investigated the relationship of intrathoracic findings of pleural plaques with clinicopathological features and prognosis. RESULTS: Pleural plaques were found in 121/701 patients (17.3%) during surgery. The incidence of squamous cell carcinoma (P < 0.001) and the pathological stage (P = 0.021) were higher in patients with pleural plaques. Overall survival was significantly worse in patients with pleural plaques (5-year rate; 64.5% vs. 79.3%; P < 0.001), and the same finding was noted in clinical stage I patients (5-year rate; 64.8% vs. 83.4%; P < 0.001). In multivariable analysis, the presence of pleural plaques was a significant predictor of overall survival in patients with clinical stage I (hazard ratio, 1.643; P = 0.036). In the analysis among patients with emphysema more severe than Goddard score 5 points or interstitial pneumonia, overall survival was significantly worse in those with pleural plaques than in those without pleural plaques (5-year rate; 66.3% vs. 49.5%; P < 0.001). CONCLUSIONS: Patients with non-small cell lung cancer who underwent resection and demonstrated pleural plaques intraoperatively had a significantly worse prognosis. It is important to recognize the presence of pleural plaques intraoperatively, and our findings will be useful in determining the treatment and follow-up strategy for such patients with lung cancer and pleural plaques on intrathoracic examination.

Thrombocytopaenia successfully treated by a multilocular thymic cyst resection.

The multilocular thymic cyst (MTC) is a rare, acquired disease caused by inflammatory changes in the thymus, and is associated with autoimmune diseases. We report a case of MTC with thrombocytopaenia, which improved following surgical resection. A 45-year-old man developed thrombocytopaenia with an anterior mediastinal tumour. Thrombocytopaenia due to an autoimmune mechanism, associated with thymoma or thymus-related disease, was suspected. Pathologic analysis following thoracoscopic thymectomy confirmed MTC. The platelet level recovered postoperatively. Our findings suggested a relationship between the acquired formation of MTC and the development of autoimmune antibodies. However, further investigation is needed to obtain more information.

Novel microwave surgical instrument for use in various lung resection situations.

A novel surgical energy device with high sealing ability using microwave technology has been developed. This novel microwave surgical instrument (MSI) is capable of sealing and dissecting a vessel ≤ 5 mm in diameter. The high sealing ability of the MSI enables fine dissection of the lung parenchyma by a scissor-type blade. This device is particularly useful in situations wherein the use of an automatic suturing instrument is difficult. Here, we describe the dissection of the lung parenchyma using this device in three patients (cases 1-3). This device was used for wedge resection of a tumor located close to the pulmonary hilum, for subsegmentectomy, and for dividing incomplete interlobar fissure (cases 1-3, respectively). In all the cases, the postoperative course was uneventful. This MSI is effective for resection of the lung parenchyma, allowing fine tissue dissection and excellent tissue sealing. This technique could assist surgeons in various lung resection cases.

[Rapid Growing Anterior Mediastinal Leiomyosarcoma with Pericardial Infiltration:Report of a Case].

Primary mediastinal leiomyosarcoma is extremely rare, and few reports in the literature have described the clinical features of this malignancy. We report a case of a small anterior mediastinal leiomyosarcoma that showed rapid growth within a short period. An 85-year-old woman showed a small anterior mediastinal tumor on chest computed tomography (CT), three months prior to presentation. Contrast-enhanced chest CT revealed rapid tumor growth, and positron emission tomography/CT revealed significant 18-fluorodeoxyglucose uptake, suggestive of malignancy. Thoracoscopic tumor resection was performed via the left thoracic approach. In addition to the tumor and surrounding anterior mediastinal tissue, we resected an area of pericardial infiltration. The tumor was diagnosed as a primary mediastinal leiomyosarcoma based on histopathological and immunohistochemical findings.

Systemic Inflammatory Score Predicts Response and Prognosis in Patients With Lung Cancer Treated With Immunotherapy.

AIM: This study aimed to investigate useful prognostic factors of immunotherapy in patients with lung cancer. PATIENTS AND METHODS: We retrospectively observed 73 patients who underwent immunotherapy (nivolumab, pembrolizumab, and atezolizumab) for lung cancer. The systemic inflammatory score (SIS) was calculated as the sum of the following factors scored one point each: Hemoglobin <12.5 g/dl and serum albumin <3.6 g/dl, resulting in scores of 0-2. We examined the correlation between the SIS and initial tumor response and progression-free and overall survival with other existing markers, namely tumor programmed death-ligand 1 (PD-L1) expression level; neutrophil-to-lymphocyte ratio (NLR); modified Glasgow prognostic score; and prognostic nutritional index, etc. Results: SIS ≤1 was significantly associated with better initial tumor response. In multivariate analysis, PD-L1 expression ≥50% (p=0.010), SIS ≤1 (p=0.028) and NLR <5.6 (p=0.047) were significantly associated with longer progression-free survival, and SIS ≤1 (p=0.030) and NLR <5.6 (p=0.037) were associated with longer overall survival. CONCLUSION: SIS is a useful marker of the efficacy of immunotherapy that can be obtained via routine blood tests.

A survived case of penetrating neck injury with intrathoracic organ damage.

BACKGROUND: Thoracic surgeons rarely encounter stab wounds with injury to the intrathoracic organs. However, such sudden and urgent situations could arise; therefore, experiences in managing such cases are invaluable. CASE PRESENTATION: An 84-year-old woman with depression who had a stab injury in the neck caused by a broad-bladed kitchen knife was brought to our facility by ambulance. She was stable in the emergency room; however, a computed tomography scan revealed that the blade had penetrated the right thoracic cavity. A right hemopneumothorax was seen. Considering the possibility of injury to the major vessels, a median sternotomy was performed. During the dissection around the blade, the patient started bleeding profusely, which required repair of an injury to the right internal jugular vein. The blade tip had penetrated the dorsal right upper lung lobe; however, it did not reach the hilum, and the knife was carefully removed. The damaged area of the lung was removed by wedge resection. CONCLUSION: Patients with deep stab wounds from knives are often hemodynamically stable because the blade acts as tamponade and prevents hemorrhage. Therefore, a surgical approach that allows for good visualization should be considered for the extraction of the blade.

Anterior Mediastinal Leiomyosarcoma: A Case Report and Literature Review.

Primary mediastinal sarcomas are extremely rare. Additionally, mediastinal leiomyosarcomas account for approximately 9% of mediastinal sarcoma cases. Until date, only few cases of anterior mediastinal leiomyosarcomas have been reported. Herein, we report a case of an 85-year-old female with an anterior mediastinal mass of 15 mm. Histological examination revealed spindle tumor cells showing a fascicular growth pattern. Immunohistochemically, the tumor cells were focal positive for desmin, calponin, and α-smooth muscle actin. The pathological diagnosis was leiomyosarcoma. In conclusion, we encountered a case of a very rare leiomyosarcoma that occurred in the anterior mediastinum, and our report may contribute to the understanding of this disease.

Lung segmentectomy with novel microwave surgical instrument (Acrosurg. Revo).

A novel model of a microwave surgical instrument (Acrosurg. Revo) which is an energy device using microwave technology and 2450 MHz microwave has recently been developed for endoscopic surgery. Herein, we describe the technique of pulmonary segmentectomy with a novel device.

Negative pressure wound therapy for broncho-pleural fistula with collapsed lung.

We present a case of the broncho-pleural fistula with a collapsed lung that was developed 2 weeks after right lower lobectomy. The patient urgently underwent open-window thoracostomy. However, the residual lung remained collapsed. To expand the lung and close the broncho-pleural fistula, negative pressure wound therapy was initiated 20 days after the procedure. The lung expanded within a few days, and the residual thoracic cavity gradually contracted. Subsequently, 2.5 months later, the remaining thoracic cavity was successfully closed using omentoplasty. No recurrence of the broncho-pleural fistula was observed for 1 year. If the lung could be inflated to reduce dead space in the thoracic cavity, broncho-pleural fistula with collapsed lung may be treated with bronchial stump coverage and negative pressure wound therapy.

Fractional excretion of tumor necrosis factor receptor 1 and 2 in patients with type 2 diabetes and normal renal function.

AIMS/INTRODUCTION: Increased concentrations of serum tumor necrosis factor (TNF) receptors (TNFRs; TNFR1 and TNFR2) are positively associated with the urinary albumin-to-creatinine ratio (ACR), and negatively associated with the estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes. However, the mechanism underlying this increase and the relationship between TNFRs in serum, and urine and kidney measures (ACR and eGFR) are unclear. MATERIALS AND METHODS: This was a cross-sectional study that included 499 patients with type 2 diabetes and eGFR ≥60 mL/min/1.73 m2 . The concentrations of TNFRs in serum and urine, and their respective fractional excretion, were measured. RESULTS: Serum and urinary TNFR levels were positively associated with the ACR, and negatively associated with the eGFR. The fractional excretion of TNFRs did not differ between patients with an eGFR ≥90 and those with an eGFR 60-89 mL/min/1.73 m2 , and also did not correlate with eGFR. After adjustment for relevant covariates, the serum TNFRs were associated with a lower eGFR (60-89 mL/min/1.73 m2 ) and an increased ACR (≥30 mg/gCr), but urinary TNFRs were associated with an increased ACR (≥30 mg/gCr) alone, in the multivariate logistic model. CONCLUSIONS: The pattern of fractional excretion TNFRs showed that an increase in serum TNFRs might result from their increased systemic production, including in the kidney, rather than being a simple reflection of GFR decline. Kidney measures appear to be strongly associated with serum TNFRs rather than urinary TNFRs in patients with type 2 diabetes and normal renal function.

Video-assisted thoracoscopic surgery using a three-dimensional thoracoscopic system as an educational tool for surgical trainees in general thoracic surgery.

OBJECTIVE: The clinical practice of safe and efficient surgery and professional development of general thoracic surgical trainee are both important issues for mentors. We investigated the usefulness of a three-dimensional (3D) endoscopic system application for lung cancer treatment as a tool for training surgical trainees. METHODS: Supervised by mentors, general thoracic surgical trainees were trained with video-assisted thoracoscopic surgery (VATS) for primary lung cancer using a 3D endoscopic system to enable them to become operators. Video clinics using 3D images were held weekly. The group using 3D endoscopic system (66 cases in the 3D-VATS group) was compared with the group using conventional two-dimensional (2D) thoracoscopic system (35 cases in the 2D-VATS group) to perform VATS lobectomies. RESULTS: There was no significant difference in operative time between both groups. However, the 3D-VATS group comprised significantly less experience than the 2D-VATS group. The intraoperative blood loss was significantly reduced for the 3D group (34 mL in the 3D-VATS group vs. 76 mL in the 2D-VATS group, P = 0.0007). There were no cases of conversion from VATS to open thoracotomy and intraoperative transfusion in either group. CONCLUSION: 3D-VATS and video clinics using 3D videos are useful training tools for general thoracic surgical trainees with little experience in open thoracotomy.

Severity of emphysema as a prognosticator of resected early lung cancer: an analysis classified by Goddard score.

OBJECTIVES: This study aimed to investigate whether the severity of emphysema as classified by Goddard score influences the prognosis of patients with early lung cancer, there are few reports about that. METHODS: From April 2009 to December 2016, we recruited 412 consecutive patients with completely resected clinical stage 0/IA/IB non-small cell lung cancer. The Goddard score assessed on preoperative computed tomography scan was retrospectively reviewed. Kaplan-Meier and Cox regression analyses were performed to assess the relationship between the Goddard score and early lung cancer prognosis. RESULTS: The patients were classified into two groups: Goddard score ≤ 4 points and ≥5 points according to the results of receiver operating characteristic curve analysis for recurrence events. The 3-year relapse-free survival rate of emphysema with Goddard score ≤ 4 points (88.6%) was higher than that of emphysema with Goddard score ≥ 5 points (60.8%) (P < 0.001). There was a higher proportion of cancer-related deaths in the group with Goddard score ≥ 5 points compared with the group with Goddard score ≤ 4 points (50% and 32.1%, respectively) (P = 0.082). A Goddard score ≥ 5 points was a significant prognostic factor for relapse-free survival in the univariate (P < 0.001) and multivariate (P = 0.022) analyses. A Goddard score ≥ 5 points was also a significant prognostic factor for overall survival in the univariate (P < 0.001) and multivariate (P = 0.041) analyses. CONCLUSION: Our findings suggest that emphysema with a Goddard score of ≥5 points may be a factor that can influence the prognosis of patients with primary lung cancer.

Tumor Endothelial Cell-Mediated Antigen-Specific T-cell Suppression via the PD-1/PD-L1 Pathway.

Tumor endothelial cells (TEC) play multiple roles in the regional specialization of vascular structure and physiology. Because TECs in the tumor microenvironment come in contact with circulating immune cells, they might influence not only trafficking but also the antitumor cellular immune response. In a mouse tumor implantation model with B16 melanoma cells, TECs expressed MHC class II, costimulating molecules, and programmed death-ligand 1 (PD-L1), suggesting that they are antigen (Ag)-presenting cells with suppressive activity. Furthermore, TECs were able to take up and present tumor-derived ovalbumin (OVA) peptide on MHC class I molecules. In functional assays, B16-OVA tumor-derived TECs significantly suppressed the proliferation and Ag-specific cytotoxicity of OVA-specific CD8+ T cells relative to those of B16 tumor-derived TECs. This suppressive activity required cell-cell contact and was abrogated by PD-L1 blockade. TECs impaired proinflammatory cytokine production of CD8+ T cells, including IL2, TNFα, and IFNγ. B16-OVA tumor-derived TECs induced immunosuppressive CD4+ T cells that suppressed OVA-specific CD8+ T-cell proliferation via inhibitory cytokines, including IL10 and TGFß. Deficiency of PD-L1 in TECs, but not in hematopoietic cells, impaired suppression and apoptosis of tumor-infiltrating CD8+ T cells, resulting in inhibition of tumor development in vivo model. These data suggest that TECs might regulate the immune response of tumor Ag-specific CD8+ T cells via the PD-1/PD-L1 pathway and induce immune suppressive CD4+ T cells in an Ag-specific manner, contributing to tumor immune evasion. IMPLICATIONS: The findings of this study might encourage the further development of novel anticancer therapies and strategies.

Safety of a Novel Microwave Surgical Instrument for Lung Parenchyma Dissection During Segmentectomy.

BACKGROUND: The choice between electrocautery or automatic suturing instruments for dissection of the lung parenchyma along the intersegmental plane during lung segmentectomy remains controversial. We hypothesized that a novel microwave surgical instrument (MSI) for dissecting the lung parenchyma could have excellent sealing effects. We examined the feasibility and safety of lung parenchymal dissection using a MSI during lung segmentectomy. METHODS: This was a prospective clinical study of lung segmentectomy involving dissection of the entire intersegmental plane using a MSI. Complications related to sealing of the lung parenchyma were evaluated and perioperative outcomes were compared to those of patients who underwent lung segmentectomy using automatic suturing instruments. Propensity score-matched comparisons were used to assess the potential impact of selection bias. RESULTS: Lung segmentectomy using a MSI was successfully performed in 30 patients. According to the propensity score matching analysis, intraoperative blood loss, length of hospital stay, and postoperative complications of the microwave group were significantly lesser (P = .019, .003, and .008, respectively) compared to those of the control group (n = 66). Prolonged air leakage was not observed. There were two cases of subcutaneous emphysema after removal of the chest tube, but no other grade 2 or higher complications were observed. No mortality occurred within 30 or 90 days postoperatively. CONCLUSIONS: The use of a MSI for lung parenchymal dissection was associated with lower blood loss during surgical procedures, reduced air leakage after the operation, and fewer postoperative complications.

Circulating kidney injury molecule-1 as a biomarker of renal parameters in diabetic kidney disease.

AIMS/INTRODUCTION: Urinary kidney injury molecule-1 (KIM-1) has been associated with proximal tubular damage in human and animal studies. Although it has been recognized as a biomarker of acute kidney injury and chronic kidney disease, its significance in the serum remains unclear. Therefore, we examined the relationship of serum and urinary KIM-1 levels with renal parameters in patients with type 2 diabetes. MATERIALS AND METHODS: Serum and urinary KIM-1 levels, together with urinary liver-type fatty acid-binding protein, were measured in 602 patients with type 2 diabetes and an estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2 . These were then compared with the urinary albumin-to-creatinine ratio and eGFR. RESULTS: The serum and urinary KIM-1 levels were significantly different among the three (eGFR ≥60, 45-59, <45 mL/min/1.73 m2 ) groups. These levels were positively associated with the albumin-to-creatinine ratio and negatively associated with eGFR. In a multivariate logistic model, both serum and urinary KIM-1 were associated with an increased albumin-to-creatinine ratio (>30 mg/g Cr), but only the serum KIM-1 was associated with a lower eGFR (<60 mL/min/1.73 m2 ), after adjustment for covariates. CONCLUSIONS: Renal parameters appear to be strongly associated with serum KIM-1, and not urinary KIM-1, in patients with type 2 diabetes and an eGFR ≥30 mL/min/1.73 m2 .