Rituximab with standard LMB chemotherapy in pediatric high-risk mature B-cell non-Hodgkin lymphoma: A report from the JPLSG B-NHL14 trial.

BACKGROUND: The benefit of adding rituximab to standard lymphomes malins B (LMB) chemotherapy for children with high-risk mature B-cell non-Hodgkin lymphoma (B-NHL) has previously been demonstrated in an international randomized phase III trial, to which the Japanese Pediatric Leukemia/Lymphoma Study Group could not participate. METHODS: To evaluate the efficacy and safety of rituximab in combination with LMB chemotherapy in Japanese patients, we conducted a single-arm multicenter trial. RESULTS: In this study, 45 patients were enrolled between April 2016 and September 2018. A total of 33 (73.3%), 5 (11.1%), and 6 (13.3%) patients had Burkitt lymphoma/leukemia, diffuse large B-cell lymphoma, and aggressive mature B-NHL, not otherwise specified, respectively. Ten (22.2%) and 21 (46.7%) patients had central nervous system disease and leukemic disease, respectively. The median follow-up period was 47.5 months. Three-year event-free survival and overall survival were 97.7% (95% confidence interval, 84.9-99.7) and 100%, respectively. The only event was relapse, which occurred in a patient with diffuse large B-cell lymphoma. Seven patients (15.6%) developed Grade 4 or higher non-hematologic adverse events. Febrile neutropenia was the most frequent Grade 3 or higher adverse event after the pre-phase treatment, with a frequency of 54.5%. CONCLUSION: The efficacy and safety of rituximab in combination with LMB chemotherapy in children with high-risk mature B-NHL was observed in Japan.

Rationale and protocol design of a phase II study of first-line osimertinib treatment for patients with poor performance status and EGFR mutation-positive non-small cell lung cancer (OPEN/TORG2040).

BACKGROUND: Cancer chemotherapy indications for patients with poor performance status and advanced lung cancer are limited. Molecular targeted drugs, including epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors, can be used in patients with poor performance status owing to their high efficacy and safety. The third-generation EGFR-tyrosine kinase inhibitor osimertinib has demonstrated effectiveness in the initial treatment of advanced EGFR mutation-positive non-small cell lung cancer in patients with good performance status; however, no evidence exists of the drug's effectiveness in patients with poor performance status in a prospective study. We designed a study that aims to investigate the efficacy and safety of first-line osimertinib treatment in patients with advanced non-small cell lung cancer harboring sensitive EGFR mutations and with poor performance status. METHODS: The OPEN/TORG2040 study is a multicenter, single-arm, phase II trial for patients with unresectable, advanced EGFR mutation-positive non-small cell lung cancer with a poor performance status (≥ 2). Eligible patients will receive osimertinib until disease progression or unacceptable toxicity. The primary endpoint is the objective response rate of the first-line osimertinib treatment. Considering a threshold value of 45%, expected value of 70% for objective response rate, one-sided significance level of 5%, statistical power of 80%, and ineligible patients, the sample size was set to 30. The secondary endpoints are disease control rate, performance status improvement rate, and safety and patient-reported outcomes using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core Quality of Life Questionnaire and Lung Cancer 13. Time to treatment failure, progression-free survival, and overall survival will also be assessed. DISCUSSION: Our study can determine the clinical benefits of osimertinib treatment in patients with poor performance status, since the clinical outcomes of patients with EGFR mutation-positive non-small cell lung cancer with poor performance status treated with this drug as a first-line treatment have not been sufficiently evaluated. TRIAL REGISTRATION: Japan Registry of Clinical Trials: jRCTs041200100 (registration date: February 12, 2021).

Discontinuation of tyrosine kinase inhibitors in pediatric chronic myeloid leukemia.

BACKGROUND: The feasibility of tyrosine kinase inhibitor (TKI) discontinuation in pediatric chronic myeloid leukemia (CML) remains to be fully elucidated. PROCEDURES: TKI was prospectively discontinued in patients who were diagnosed with CML at <20 years of age, treated with TKI for ≥3 years, and sustained molecular response 4.0 (MR4.0) for ≥2 years. Molecular relapse was defined as a single loss of major molecular response (MMR) (BCR-ABL1IS >0.1%). Relapsed patients resumed the same TKI therapy administered before discontinuation. RESULTS: Twenty-two patients with chronic-phase CML were enrolled, and the median ages at diagnosis and at TKI discontinuation were 9 (range: 1-14) years and 16 (5-26) years, respectively. The median follow-up time after TKI discontinuation was 37 months (range: 24-41 months). The median duration of TKI treatment before discontinuation was 100 (42-178) months, and that of MR4.0 was 53.5 (25-148) months. The treatment-free remission (TFR) rate at 12 months was 50.0% (90% confidence interval: 31.7%-65.8%). Eleven patients experienced loss of MMR within 4 months after TKI discontinuation and resumed TKI as originally prescribed. No progression was observed, and all 11 patients regained MR4.0 after TKI resumption. No patient had a withdrawal syndrome. The quality-of-life analysis suggested that successful TFR may improve academic performance in some patients. In patients who discontinued TKI therapy before puberty, the possibility of improvement in growth velocity upon TKI discontinuation was observed. CONCLUSIONS: TKI could be discontinued safely in patients with pediatric CML showing a sustained deep MR.

A note on confidence intervals for the restricted mean survival time based on transformations in small sample size.

Restricted mean survival time (RMST) is one measure now used to summarize time-to-event type data, but it has been pointed out that the distribution of differences in RMST deviates markedly from a normal distribution for controlled clinical trials with small sample sizes. Therefore, we conducted a numerical simulation of the RMST in which the one-sample survival time follows a Weibull distribution, comparing eight different confidence intervals combining two types of variance with four types of variable transformations, including no transformation. The evaluation items were the coverage probability and the above and below error probabilities for the true value. The variance types were based on Greenwood's formula and its Kaplan-Meier correction. The arcsine square root transformation, logit transformation, and complementary log-log transformation were used as the variable transformations. When the sample size was small and the event rate was low, the confidence interval of the untransformed RMST tended to have a small coverage probability and to be overestimated. Variance by Kaplan-Meier correction improved the coverage. The problems of coverage and overestimation were also improved by variable transformations, and in particular, applying the logit transformation and the complementary log-log transformation both resulted in substantial improvements. Our study suggested that it is preferable to construct the confidence intervals of RMST using the logit transformation for variances based on Greenwood's formula in small sample size trials. The SAS code to replicate the analyses is available at https://github.com/HiroyaHashimoto/SAS-Programs.

Measuring Quality of Care for Ischemic Stroke Treated With Acute Reperfusion Therapy in Japan　- The Close The Gap-Stroke.

BACKGROUND: In Japan there is no consensus on how to efficiently measure quality indicators (QIs), defined as a standard of care, for acute ischemic stroke (AIS). Using information from a health insurance claims database and electronic medical records, we evaluated the feasibility and validity of measuring QIs for AIS patients who received intravenous recombinant tissue plasminogen activator (IV rt-PA) or endovascular therapy (EVT).Methods and Results:AIS patients receiving rt-PA or EVT between 2013 and 2015 were identified. We selected 17 AIS QI measures for primary stroke centers (PSCs) and 8 for comprehensive stroke centers (CSCs). Defined QIs were calculated for each hospital and then averaged. In total, the data of 8,206 patients (rt-PA 83.7%, EVT 34.9%) from 172 hospitals were obtained. Median National Institute of Health Stroke Scale score at admission was 14, and 37.7% of the patients were functionally independent at discharge. All target QIs were successfully measured with fewer missing values, and the accuracy of preset data was about 90%. Adherence rates were low (<50%) in 5 QI measures among PSCs, including door-to-needle time ≤1 h, and in 1 QI measure among CSCs (door-to-brain and vascular imaging time ≤30 min). CONCLUSIONS: Measuring QIs for AIS by this novel approach was feasible and reliable in the provision of a national benchmark.

Alectinib for relapsed or refractory anaplastic lymphoma kinase-positive anaplastic large cell lymphoma: An open-label phase II trial.

Anaplastic lymphoma kinase (ALK) inhibition is expected to be a promising therapeutic strategy for ALK-positive malignancies. We aimed to examine the efficacy and safety of alectinib, a second-generation ALK inhibitor, in patients with relapsed or refractory ALK-positive anaplastic large cell lymphoma (ALCL). This open-label, phase II trial included patients (aged 6 years or older) with relapsed or refractory ALK-positive ALCL. Alectinib 300 mg was given orally twice a day (600 mg/d) for 16 cycles, and the duration of each cycle was 21 days. Patients who weighed less than 35 kg were given a reduced dose of alectinib of 150 mg twice a day (300 mg/d). Ten patients were enrolled, and the median age was 19.5 years (range, 6-70 years). Objective responses were documented in eight of 10 patients (80%; 90% confidence interval, 56.2-95.9), with six complete responses. The 1-year progression-free survival, event-free survival, and overall survival rates were 58.3%, 70.0%, and 70.0%, respectively. The median duration of therapy was 340 days. No unexpected adverse events occurred. The most common grade 3 and higher adverse event was a decrease in neutrophil count in two patients. Alectinib showed favorable clinical activity and was well tolerated in patients with ALK-positive ALCL who had progressed on standard chemotherapy. Based on the results of the current study, the Ministry of Health, Labour and Welfare of Japan approved alectinib for the treatment of recurrent or refractory ALK-positive ALCL in February 2020.

A Prospective, Randomized Trial Comparing Respiratory Status During Anesthesia for Airway Stenting: Spontaneous Respiration Versus Controlled Ventilation With Muscle Relaxants.

BACKGROUND: Airway stenting is a procedure in which a stent is inserted into a stenotic site of the airway. The safest method of ventilation for airway stenting is controversial. A prospective randomized interventional study was conducted on airway stenting. We conducted this study to investigate whether controlled ventilation with muscle relaxants (MR) during airway stenting reduces the incidence of desaturation events (percutaneous oxygen saturation [SpO2] <95%) in comparison with spontaneous respiration (SP). METHODS: Sixty-four patients were enrolled at our hospital between April 2016 and August 2018, and were randomly assigned to the controlled ventilation with MR group or SP group. For anesthesia, total intravenous anesthesia with propofol target-controlled infusion and remifentanil was performed. In the SP group, SP was maintained. In the MR group, a rigid bronchoscope was inserted after the administration of MR to perform controlled ventilation. The incidence of desaturation events was analyzed by logistic regression adjusted by the preoperative respiratory state and stenotic site of the airway. RESULTS: The incidence of desaturation events in the SP and MR groups was 75.0% (24/32) and 9.7% (3/31), respectively, with an odds ratio of 0.04 (95% confidence interval, 0.01-0.16, reference = SP group; P < .001). In the SP group, the mean intraoperative pH was lower than that in the MR group (7.2 ± 0.1 vs 7.4 ± 0.1, respectively; P < .001). In this group, the mean partial pressure of arterial carbon dioxide (PaCO2) was higher (70.2 ± 17.0 mm Hg vs 40.5 ± 8.0 mm Hg, respectively; P < .001) and the mean partial pressure of oxygen in the arterial blood/fraction of the inspiratory oxygen ratio was lower (263.1 ± 64.2 mm Hg vs 396.4 ± 69.4 mm Hg, respectively; P < .001). CONCLUSIONS: Controlled ventilation with MR during airway stenting reduced the incidence of desaturation events, maintaining a favorable respiratory status.

A Multicenter, Open-label, Clinical Trial to Assess the Effectiveness and Safety of Allogeneic Hematopoietic Stem Cell Transplantation Using Reduced-intensity Conditioning in Relapsed/refractory Anaplastic Large-cell Lymphoma in Children.

No standard treatment for relapsed or refractory anaplastic large-cell lymphoma (ALCL) has been established. This study is a multicenter, open-label trial to examine the effectiveness and safety of transplantation with reduced-intensity conditioning (RIC) for patients under 20 years old with relapsed or refractory ALCL. We defined RIC as the administration of fludarabine (30 mg/m2/day) for five days plus melphalan (70 mg/m2/day) for two days and total body irradiation at 4 Gy, followed by allogeneic hematopoietic stem cell transplantation.

Development of Quality Indicators of Stroke Centers and Feasibility of Their Measurement Using a Nationwide Insurance Claims Database in Japan　­ J-ASPECT Study ­

BACKGROUND: We aimed to develop quality indicators (QIs) related to primary and comprehensive stroke care and examine the feasibility of their measurement using the existing Diagnosis Procedure Combination (DPC) database. METHODS AND RESULTS: We conducted a systematic review of domestic and international studies using the modified Delphi method. Feasibility of measuring the QI adherence rates was examined using a DPC-based nationwide stroke database (396,350 patients admitted during 2013-2015 to 558 hospitals participating in the J-ASPECT study). Associations between adherence rates of these QIs and hospital characteristics were analyzed using hierarchical logistic regression analysis. We developed 17 and 12 measures as QIs for primary and comprehensive stroke care, respectively. We found that measurement of the adherence rates of the developed QIs using the existing DPC database was feasible for the 6 QIs (primary stroke care: early and discharge antithrombotic drugs, mean 54.6% and 58.7%; discharge anticoagulation for atrial fibrillation, 64.4%; discharge antihypertensive agents, 51.7%; comprehensive stroke care: fasudil hydrochloride or ozagrel sodium for vasospasm prevention, 86.9%; death complications of diagnostic neuroangiography, 0.4%). We found wide inter-hospital variation in QI adherence rates based on hospital characteristics. CONCLUSIONS: We developed QIs for primary and comprehensive stroke care. The DPC database may allow efficient data collection at low cost and decreased burden to evaluate the developed QIs.

Phase II Study of Treatment for Newly Diagnosed Multiple Myeloma Patients Over 75 Years Old with Alternating Bortezomib/dexamethasone and Lenalidomide/dexamethasone: the MARBLE Trial.

Elderly multiple myeloma (MM) patients, who are generally ineligible for transplantation, have high risks of death and treatment discontinuation, and require a regimen incorporating novel agents that balance safety, tolerability, and efficacy. We evaluated alternating bortezomib-dexamethasone and lenalidomide-dexamethasone treatments administered over a 63-day cycle in transplant-ineligible elderly patients with newly diagnosed MM. Subcutaneous bortezomib 1.3 mg/m2 was administered weekly on Days 1, 8, 15, and 22; oral lenalidomide 15 mg daily on Days 36-56; and oral dexamethasone 20 mg on Days 1, 8, 15, 22, 36, 43, 50, and 57 for 6 cycles. The primary endpoint was the overall response rate.

Phase II Trial Using Romidepsin after Gemcitabine, Dexamethasone, and Cisplatin Therapy in Elderly Transplant-Ineligible Patients with Relapsed/Refractory Peripheral T-Cell Lymphoma: Study Protocol.

Romidepsin is an important therapeutic option for patients with peripheral T-cell lymphoma (PTCL). However, the timing of romidepsin administration remains controversial. Romidepsin was launched in Japan as a consolidation therapy agent after conventional salvage chemotherapy with gemcitabine, dexamethasone, and cisplatin (GDP). GDP therapy will be administered every 3 weeks. If complete response, partial response, or stable disease is confirmed after 2-4 GDP cycles, romidepsin will be administered every 4 weeks. The primary endpoint is a 2-year progression-free survival rate. Patients participating in this study and undergoing treatment can expect results similar to or better than those of conventional therapies.

Phase I clinical study of brentuximab vedotin (SGN-35) involving children with recurrent or refractory CD30-positive Hodgkin's lymphoma or systemic anaplastic large cell lymphoma: rationale, design and methods of BV-HLALCL study: study protocol.

BACKGROUND: Hodgkin's lymphoma (HL) and anaplastic large-cell lymphoma (ALCL) are the two most common tumors expressing CD30. Internationally, a clinical study that is being conducted involving adults with recurrent or refractory HL or ALCL suggests efficacy of brentuximab vedotin (SGN-35). Pediatric patients should be given medicines that have been appropriately evaluated for their use. In the past, however, new approved drugs have been used for pediatric patients without the confirmation of safety and efficacy in pediatric patients. Therefore, it is important to examine the safety and efficacy of SGN-35 in Japanese children. METHODS: Phase I clinical study of SGN-35 involving children with recurrent or refractory CD30-positive Hodgkin's lymphoma or systemic anaplastic large cell lymphoma (BV-HLALCL study) is being conducted for pediatric patients in order to evaluate the safety, feasibility and preliminary clinical effectiveness of brentuximab vedotin. SGN-35 is intravenously administered on Day 1 of each cycle (21 days/cycle). The dose of SGN-35 is calculated based on the body weight at the baseline. The primary endpoint is dose limiting toxicity and incidence of adverse events. The secondary endpoints are pharmacokinetics, response rate, complete remission rate, response duration, progression-free survival and event-free survival. The reduction rate of tumor will be calculated according to revised response criteria for malignant lymphoma for measurable tumor. Six pediatric patients will be enrolled in this study. DISCUSSION: This study aims to expand indication of SGN-35 in Japan by assessing its safety and efficacy in pediatric patients. TRIAL REGISTRATION: JMACCT ID: JMA-IIA00229 . Registered on 17 Nov 2015.

Phase II/III study in children and adolescents with newly diagnosed B-cell precursor acute lymphoblastic leukemia: protocol for a nationwide multicenter trial in Japan.

B-cell precursor acute lymphoblastic leukemia is the most common pediatric malignancy, but its treatment needs to be modified to cause low acute toxicity and few late complications with a high cure rate. In this trial, we will stratify patients with B-cell precursor acute lymphoblastic leukemia into standard, intermediate and high risk groups according to prognostic factors. In addition, we will establish an evaluation system for minimal residual disease that will enable us to stratify patients based on minimal residual disease in subsequent clinical trials. We will clarify the impact of dexamethasone/vincristine pulse therapy during maintenance therapy in the standard risk group, and intensive l-asparaginase therapy in the intermediate risk group. In the high risk group, usefulness of vincristine intensification will be assessed. This trial has been registered in the UMIN Clinical Trials Registry as UMIN000009339 [http://www.umin.ac.jp/ctr/].

Unfavorable effects of history of volume overload and late referral to a nephrologist on mortality in patients initiating dialysis: a multicenter prospective cohort study in Japan.

BACKGROUND: Patients with late referral and positive history of volume overload may have a poor prognosis after initiating dialysis due to insufficient and/or inadequate management of complications of renal failure and the lack of better dialysis preparation. Little is known about the influence of the relationship between history of volume overload and late referral on prognosis. METHODS: We analyzed 1475 patients who had initiated dialysis for the first time from October 2011 to September 2013. late referral was defined as referral to a nephrologist < 3 months before dialysis initiation. The major outcomes were all-cause death and deaths due to cardiovascular diseases (CVD). The impact of late referral and history of volume overload on all-cause mortality was assessed by Cox proportional hazards models. RESULTS: Among 1475 patients, the mean patient age was 67.5 years. During the median follow-up of 2.2 years, 260 deaths occurred; 99 were due to CVD. Cox proportional hazards models demonstrated that late referral (adjusted hazard ratio [HR], 1.35; 95% confidence interval [CI], 1.00-1.82) and history of volume overload (adjusted HR, 1.39; 95% CI, 1.06-1.81) were risk factors for all-cause mortality. Furthermore, late referral coexisting was associated with a history of volume overload increased mortality (adjusted HR, 2.10; 95% CI, 1.39-3.16 versus absence of late referral without history of volume overload) after adjusting for age, sex, diabetes, atherosclerotic disease, and laboratory values. CONCLUSIONS: Both late referral and history of volume overload were associated with increased risks of all-cause mortality. TRIAL REGISTRATION: University Hospital Medical Information Network (UMIN000007096). Registered 18 January 2012, retrospectively registered. https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000008349 .

Pediatric acute lymphoblastic leukemia: Proportion of patients who continue hospital visits.

BACKGROUND: Long-term follow up in adulthood after childhood cancer therapy is particularly important because of the risk of late effects, and information on the rate of continuing hospital visits by childhood cancer survivors (CCS) is also important for the planning of studies on the risk of late effects. METHODS: The rate of continuing hospital visits ("long-term follow up") in 1,252 cases registered in the multicenter Japan Association of Childhood Leukemia Study on Acute Lymphoblastic Leukemia (JACLS ALL-02) was investigated using data from its electronic data capture (EDC) system, including case number, date of diagnosis, date of therapy completion, date of birth, sex, survival or death, date of death, date of last outcome confirmation, and facility code. EDC entries of confirmed survival or death during the 2 years preceding the data lock represented continuing visitors, and the number of those cases, divided by the total number of cases (excluding cases of confirmation of death prior to those 2 years), was calculated as the proportion of continuing visitors (PCV). RESULTS: The PCV for survivors of childhood acute lymphoblastic leukemia was found to decline over time from diagnosis. For subjects aged 21-29 years who were ≥9 years from diagnosis, PCV was approximately 30% overall, representing 23.5% for men and 41.8% for women, thus indicating a gender difference. CONCLUSIONS: Further studies may be necessary to assess whether CCS who stopped visiting childhood cancer treatment facilities, actually received therapeutic intervention or appropriate screening for late effects as adults.

A Phase I/II Study of Crizotinib for Recurrent or Refractory Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma and a Phase I Study of Crizotinib for Recurrent or Refractory Neuroblastoma : Study Protocol for a Multicenter Single-arm Open-label Trial.

Crizotinib is an inhibitor of multiple tyrosine kinases, including the anaplastic lymphoma kinase (ALK). Responses to crizotinib have also been reported in patients with ALK-positive anaplastic large-cell lymphoma (ALCL) and solid tumors with ALK-mutation, including neuroblastoma. Optimal treatment for patients with recurrent or refractory ALK-positive ALCL and neuroblastoma has not been established. There is a need to develop new drugs for these patients. The objectives of this trial are to evaluate the tolerability and safety of crizotinib in Japanese patients with recurrent/refractory ALK-positive ALCL or neuroblastoma (phase I) and its efficacy in recurrent/refractory ALK-positive ALCL (phase II).

Development of an Oropharyngeal Scope with an Integrated Tongue Depressor: NTOP2013 Study.

The oropharynx is examined with a light source such as an electric light, a penlight, or a forehead mirror based on an acquired visual field using a tongue depressor. However, it is extremely difficult to obtain objective and reproducible images of tissue within the pharynx required in recent years with these methods, and insufficient progress in the examination tools has been made. There is an increasing need to develop a method for display during oropharyngeal examination. We conducted the present study to develop a novel oropharyngeal endoscope as an objective observation method.

The Effect of Interim FDG-PET-guided Response-Adapted Therapy in Pediatric Patients with Hodgkin's Lymphoma (HL-14) : Protocol for a Phase II Study.

This trial enrolls patients with untreated Hodgkin's lymphoma aged<20 years at diagnosis and examines the effects of omitting radiation therapy if the FDG-positron emission tomography (PET) findings after two completed cycles of combination chemotherapy are negative. It thereby aims to determine whether patients who truly require radiation therapy can be identified by FDG-PET. If so, this modality could be used to omit radiation therapy for all other patients, decreasing the risk of serious long-term complications without affecting survival rates. The outcomes of patients for whom FDG-PET is used to assess early treatment response will also be determined.

High-dose Dexamethasone Therapy as the Initial Treatment for Idiopathic Thrombocytopenic Purpura: Protocol for a Multicenter, Open-label, Single Arm Trial.

Standard therapy for idiopathic thrombocytopenic purpura (ITP) has not been established. We are conducting a multicenter, prospective trial to determine the efficacy and safety of short-term, high-dose dexamethasone therapy in ITP patients aged 18-80 years with platelet counts of <20, 000 /µL, or with <50, 000/ µL and bleeding symptoms. The primary endpoints of this trial are the proportion of responses (complete plus partial response) on day 180 (day 46+180) after the completion of the 46-day high-dose dexamethasone therapy. The results of this investigation of the effectiveness and safety of this regimen will be essential for the establishment of standard therapy for ITP.

Development and validation of a score for evaluating comprehensive stroke care capabilities: J-ASPECT Study.

BACKGROUND: Although the Brain Attack Coalition recommended establishing centers of comprehensive care for stroke and cerebrovascular disease patients, a scoring system for such centers was lacking. We created and validated a comprehensive stroke center (CSC) score, adapted to Japanese circumstances. METHODS: Of the selected 1369 certified training institutions in Japan, 749 completed an acute stroke care capabilities survey. Hospital performance was determined using a 25-item score, evaluating 5 subcategories: personnel, diagnostic techniques, specific expertise, infrastructure, and education. Consistency and validity were examined using correlation coefficients and factorial analysis. RESULTS: The CSC score (median, 14; interquartile range, 11-18) varied according to hospital volume. The five subcategories showed moderate consistency (Cronbach's α = 0.765). A strong correlation existed between types of available personnel and specific expertise. Using the 2011 Japanese Diagnosis Procedure Combination database for patients hospitalized with stroke, four constructs were identified by factorial analysis (neurovascular surgery and intervention, vascular neurology, diagnostic neuroradiology, and neurocritical care and rehabilitation) that affected in-hospital mortality from ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The total CSC score was related to in-hospital mortality from ischemic stroke (odds ratio [OR], 0.973; 95% confidence interval [CI], 0.958-0.989), intracerebral hemorrhage (OR, 0.970; 95% CI, 0.950-0.990), and subarachnoid hemorrhage (OR, 0.951; 95% CI, 0.925-0.977), with varying contributions from the four constructs. CONCLUSIONS: The CSC score is a valid measure for assessing CSC capabilities, based on the availability of neurovascular surgery and intervention, vascular neurology, diagnostic neuroradiology, and critical care and rehabilitation services.