Kushiro Rosai Hospital

Colorectal cancer (CRC) exhibits substantial molecular heterogeneity, yet detailed single-cell transcriptomic data from Japanese patients remain limited. Here, we performed single-cell RNA sequencing (scRNA-seq) on tumor tissues and adjacent normal tissues from four Japanese CRC patients to characterize malignant cell populations. We identified a common cancer-associated cell cluster observed across all four cases, characterized by high expression of the long noncoding RNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1). Further analysis revealed a marked decrease in Ras Association Domain Family Member 6 (RASSF6) expression within this cluster, despite clinical datasets reporting that elevated RASSF6 expression correlates with poor overall survival in Western cohorts. Reanalysis of publicly available bulk RNA-seq data from independent East Asian cohorts confirmed that RASSF6 expression was consistently reduced in tumor tissues compared with adjacent normal colon tissues, while KCNQ1OT1 expression showed no apparent differences across cohorts. Collectively, our single-cell analysis delineates a recurrent cancer-associated transcriptional state observed within this cohort and highlights distinct gene expression features that may be underappreciated by bulk or population-averaged analyses, underscoring the value of single-cell profiling for refining molecular interpretations of CRC.

Fracture Liaison Service (FLS) programs are beneficial for reducing the frequency of subsequent fractures and mortality in post-hip fracture patients. The aim of this study was to investigate recent changes in the rate of pharmaceutical treatment for osteoporosis in post-hip fracture surgery patients in the absence of FLS programs compared to the previous 10 and 20years, and whether introduction of a new reimbursement scheme in hip fracture care, launched in 2022 by the Japanese government, improved the pharmaceutical treatment rate after surgical intervention. Study 1 included 1490 post-hip fracture patients in seven hospitals without an FLS program. Study 2 included 396 osteoporosis patients who were covered by the new reimbursement scheme at five of the seven hospitals. Treatment-related variables and the number of patients who received the different pharmaceutical treatments at 0, 3, 6 and 12months after discharge from the hospital were examined. Two hundred and thirty-two of 1474 patients received anti-osteoporotic medication at hospital discharge, which was not a significant improvement in the rate of pharmaceutical treatment in comparison with that in our previous studies over 20years. On the other hand, introduction of the new reimbursement scheme at hospitals significantly improved the rate of pharmaceutical treatment, with 263 of the 391 patients receiving anti-osteoporotic medication at discharge, as well as a significant improvement. We demonstrated a significant improvement in the pharmaceutical treatment rate for osteoporosis in post-hip fracture surgery patients after introduction of the new reimbursement scheme launched by the Japanese government.

Clazosentan (CLZ) therapy prevents delayed ischemia following aneurysmal subarachnoid hemorrhage (aSAH), but non-ischemic adverse events necessitate optimized protocols. This study presents outcomes of contemporary CLZ therapy under a unified protocol and identifies factors influencing delayed ischemic and non-ischemic adverse events following aSAH. This multicenter prospective registry analyzed data from 80 aSAH patients receiving CLZ therapy (April 2023 - October 2024). Primary endpoints were delayed ischemic events and non-ischemic adverse events; secondary endpoint was favorable outcome (modified Rankin Scale 0-2) at discharge or six weeks post-onset. Delayed ischemic events occurred in 19 patients (23.8%), including delayed ischemic neurological deterioration (8.8%), moderate-to-severe cerebral vasospasm (20.0%), and symptomatic delayed cerebral infarction (7.5%). Non-ischemic adverse events were observed in 22 patients (27.5%). Favorable outcomes were achieved in 52 patients (65.0%). Delayed ischemic events were associated with female sex, poor severity grades, higher Fischer scale scores, and elevated neutrophil-to-lymphocyte ratios. Non-ischemic adverse events were associated with older age, anemia, hypoproteinemia, and elevated cardiothoracic ratios. Multivariate analysis identified non-ischemic adverse events as significant for unfavorable outcomes (FDR p <.001), whereas delayed ischemic events were not (FDR p =.705). Among non-ischemic adverse events, pulmonary edema was the strongest factor associated with unfavorable outcomes. In conclusion, CLZ therapy with appropriate candidate selection and management protocol appears promising as a treatment option to prevent delayed ischemia after aSAH, though potential confounders warrant careful consideration. Addressing clinical risk factors for non-ischemic adverse events may further enhance treatment outcomes. Clinical trial number Not applicable.

e15563 Background: FOLFIRI plus aflibercept (AFL) or bevacizumab (BEV) are significant therapeutic options for patients with metastatic colorectal cancer (mCRC) who have failed prior oxaliplatin-based chemotherapy. While accumulating evidence suggests an association between the tumor microenvironment, inflammation, and the prognosis of mCRC, biomarkers predictive of response to these chemotherapy regimens remain unknown. Studies have demonstrated that AFL exerts biological effects on macrophages within the tumor microenvironment. Methods: We conducted a multi-institutional retrospective biomarker study to analyze the relationship between CD68, CD163 (M2 macrophage), iNOS (M1 macrophage), and S100A4 expression in biopsy or surgical colon samples and the efficacy of FOLFIRI plus AFL (cohort A) or plus BEV (cohort B) in Japanese patients with mCRC who failed prior treatment with 5-fluorouracil + oxaliplatin + anti-EGFR agent. The primary outcome was overall response rate (ORR), and the secondary outcome was progression-free survival (PFS) according to the biomarker status. The expression of biomarkers was evaluated independently using immunohistochemical staining scores (IHCSS) by three investigators, including a board-certified pathologist. Statistical analyses were performed using the chi-square test and log-rank test. Results: Forty patients were enrolled in the study, including 19 in cohort A and 21 in cohort B. The median age was 67.5 years (range, 36-79), and 25 patients (62.5%) were male. The ORR was 26.3% in cohort A and 19.0% in cohort B, while median PFS was 11.1 months and 7.1 months, respectively. The percentage of cases that were positive for CD68, CD163, iNOS, and S100A4 were 78.9%, 26.3%, 57.9%, and 89.5% in cohort A, 42.9%, 38.1%, 81.0%, and 81.0% in cohort B. Among these biomarkers, none demonstrated a statistically significant association with outcomes, although the Kaplan-Meier plot and PFS at 6 and 12 months indicated a potential trend suggesting that patients with iNOS-negative tumors may exhibit improved PFS, particularly in cohort A (Table). Conclusions: In our biomarker study of patients with mCRC treated with FOLFIRI plus AFL or BEV, none of the analyzed biomarkers associated with macrophages in the tumor microenvironment demonstrated significant correlations with treatment outcomes. The observed trend towards improved PFS in iNOS-negative tumors treated with AFL merits further investigation, and larger prospective studies are necessary to elucidate this potential relationship. Progression-free survival at 6 and 12 months. Progression-free survival 6 months 12 months All iNOS pos (n=28 ) 46.4 % (13) 21.4 % (6) iNOS neg (n= 12) 83.3 % (10) 50.0 % (6) Cohort A iNOS pos (n= 11) 45.5 % (5) 18.2 % (2) iNOS neg (n= 8) 87.5 % (7) 50.0 % (4) Cohort B iNOS pos (n= 17) 47.1 % (8) 23.5 % (4) iNOS neg (n= 4) 75.0 % (3) 50.0 % (2)

447 Background: Ramucirumab (RAM) has shown efficacy in combination with paclitaxel (PTX) or irinotecan in the second-line treatment of advanced gastric cancer (AGC). However, the efficacy and safety regarding the combination therapy of RAM and docetaxel (DTX) have not been reported. We hypothesized that RAM plus DTX for patients with AGC could be as effective as RAM plus PTX and could reduce the incidence of neuropathy. Methods: HGCSG 1903 was a non-randomized, single arm, phase 2 trial carried out at 20 institutes in Japan. AGC patients with refractory or intolerance to primary chemotherapy were eligible. RAM (8 mg/kg on day1 and 15) plus DTX (60 mg/m 2 on day1) combination therapy administered in 28-day cycle were continued until disease progression or emergence of adverse events requiring discontinuation. The primary endpoint was response rate (RR) with threshold value of 10.7% and an expected value of 27.9%. A total of 35 cases are planned for registration. The secondary endpoints were overall survival (OS), progression-free survival (PFS), and safety. This trial was registered with Japan Registry of Clinical Trials, number jRCTs011200010. Results: Between Nov 2020 and Dec 2023, 36 patients were enrolled. Median age was 70 (range, 36–82); female/male were 7/29; ECOG PS 0/1, 16/20, respectively. One patient did not initiate study treatment at the onset of bowel obstruction after enrollment. In the efficacy and safety analysis set of 35 patients, RR was 25.7% (95%C.I., 12.5–43.3%) and disease control rate was 74.3% (95%C.I., 56.7–87.5%). Median OS and PFS were 11.9 months (95%C.I., 3.0–20.7) and 3.1 months (95%C.I., 2.1–4.2), respectively. Grade 3 or higher adverse events that occurred in more than 5% of patients were neutropenia (68.6%), leucopenia (57.1%), febrile neutropenia (17.1%), hypertension (14.3%), anorexia (11.4%), anemia (8.6%), and fatigue (5.7%). Grade 4 neutropenia occurred in 60.0% of patients. The protocol was amended to allow primary G-CSF prophylaxis during study period. The number of patients who received primary G-CSF prophylaxis after the amendment was 7/13 (53.8%). Neuropathy occurred in 65.7% of all grades, with no incidence of grade 3 or higher. No death and new safety signals with a causal relation to study treatment were observed. Conclusions: The primary endpoint of response rate was met in HGCSG 1903. Although neutropenia and febrile neutropenia may be more frequent, they were manageable. RAM plus DTX might be considered as an option for second-line treatment of patients with AGC. Clinical trial information: jRCTs011200010.

Acute myeloid leukemia (AML) is an aggressive hematological malignancy with genetic alterations. The FMS-like tyrosine kinase 3 (FLT3) gene is frequently mutated in adult de novo AML, with two types of mutations: internal tandem duplication (ITD) and point mutations in the tyrosine kinase domain. This study aimed to investigate the impact of FLT3 inhibitors and hematopoietic cell transplantation (HCT) on survival outcomes in patients with FLT3-ITD AML in a real-world setting. We retrospectively analyzed 139 patients with FLT3-ITD-positive AML between 2012 and 2021. The median age was 63 years. In the propensity score-matched cohort, FLT3 inhibitors improved overall survival (OS) compared with patients treated without FLT3 inhibitors (3-year OS: 33.7% vs. 25.8%, p = 0.021). Patients who underwent HCT had superior outcomes to those without HCT (3-year OS: 45.3% vs. 2.2%, p < 0.0001). The combination of FLT3 inhibitors and HCT resulted in the highest OS and relapse-free survival (RFS) rates (3-year OS: 62.4%; 3-year RFS: 44.4%). Disease status before transplantation did not predict the prognosis, but use of FLT3 inhibitors increased survival in patients without complete remission before HCT. These results demonstrate the clinical impact of FLT3 inhibitors on survival outcomes in patients with FLT3-ITD-positive AML, particularly when combined with HCT. FLT3 inhibitors can improve the prognosis of AML with FLT3 mutations, especially in patients who undergo HCT.