Background: Allogeneic hematopoietic stem cell transplant (Allo-HSCT) recipients are still at increased risk of severe COVID-19 infection. Vaccination is a critical strategy to protect this population. This real-world prospective cohort study aimed to evaluate the immune response and clinical outcomes of COVID-19 vaccines in Allo-HSCT recipients. Methods: Allo-HSCT recipients (median age: 48 years) who received either the BNT162b2 or CoronaVac vaccines were included. Antibodies against the SARS-CoV-2 spike protein were quantitatively measured using the chemiluminescent microparticle immunoassay. Patient- and vaccine-related factors affecting antibody responses were analyzed. Adverse events, including graft-versus-host disease (GVHD) and post-vaccine infections, were recorded. Results: Among 95 Allo-HSCT recipients, 86.3% achieved adequate antibody responses following COVID-19 vaccination. Patients receiving ≥3 vaccine doses showed significantly higher antibody titers compared to those with only 2 doses (OR: 0.11; 95% CI: 0.02–0.53; p = 0.006 **). The use of Ruxolitinib or Ibrutinib was associate with increased odds of low antibody response (OR: 38.39; 95% CI: 3.14–468.95; p = 0.004 **). Hypogammaglobulinemia (low serum IgG levels) was associated with a reduced antibody response (OR: 0.17; 95% CI: 0.03–0.96; p = 0.045 *), while no significant correlation was found between serum IgA levels and antibody responses (p = 0.672). Three cases of post-vaccine GVHD were observed, and no fatalities related to COVID-19 occurred during the study. Conclusions: COVID-19 vaccination is safe and effective in Allo-HSCT recipients, with stronger responses especially following ≥3 vaccine doses. Patients receiving GVHD treatment or with hypogammaglobulinemia exhibited impaired responses, emphasizing the need for tailored vaccination strategies and close monitoring in this population.

Objective: The discovery of imatinib was a milestone for chronic myeloid leukemia (CML). As the life expectancy of CML patients has approached that of the general population, research has shifted towards improving quality of life and economic considerations. After 2010, it was shown that some patients could maintain molecular response even after discontinuing imatinib. This national multicenter prospective cohort study aimed to observe the long-term consequences of discontinuing imatinib therapy in adult chronic-phase CML patients. Materials and Methods: We enrolled 41 CML patients from 4 different centers in this non-randomized single-arm trial. Molecular responses of all patients were re-evaluated using real-time polymerase chain reaction at a single center. The median follow-up time after imatinib discontinuation was 48 months (minimum-maximum: 6-81 months). Results: The rate of molecular relapse-free survival at 48 months was 33.2% (confidence interval: 48.2-18.2). Twenty-seven of 41 patients lost their major molecular response, treatment was started again, and deep molecular response was re-achieved with imatinib in all cases. There was no significant relationship between molecular relapse and clinical factors such as duration of treatment or molecular response status. Discontinuing imatinib resulted in savings of approximately 4,392,000 Turkish lira or 245,150 US dollars. Conclusion: Tyrosine kinase inhibitor discontinuation with close molecular monitoring is a safe option and provides important national economic benefits for chronic phase CML patients. This approach should be considered for all eligible patients. This is the first tyrosine kinase inhibitor discontinuation study from Turkiye.

Introduction: Both aging and malignancy are associated with an increased risk of infections, including bloodstream infections. Despite their clinical significance, research concentrating on the epidemiology, outcomes, and risk factors influencing mortality in older cancer patients is still limited. This study aims to examine the epidemiology of bloodstream infections and factors contributing to mortality among older cancer patients. Methodology: This retrospective cohort study was conducted at Etlik City Hospital from January to December 2023. The subjects included cancer patients aged 65 years and older who had experienced bloodstream infections and received a minimum of 48 hours of antimicrobial therapy. Data, including demographics, clinical features, microbiological findings, and antimicrobial therapy, were collected. Bloodstream infections were categorized as either hospital-acquired or community-acquired infections and further classified by their source. Results: Among 160 bloodstream infection episodes observed, 68.8% of them occurred in patients with solid tumors, while 31.3% were found in those with hematological malignancies. Hospital-acquired infections comprised 78.8% of the total cases. Mortality was significantly associated with inappropriate initial antimicrobial therapy, carbapenem resistance, and multidrug resistance. Additionally, patients who presented with septic shock and fungal infections had higher mortality rates. Conclusion: The findings underscore the urgent need for early implementation of appropriate antimicrobial therapy and effective infection control measures. The persistence of multidrug resistance and hospital-acquired infections presents critical challenges in reducing mortality rates among older cancer patients. The development of tailored infection management strategies and robust antimicrobial stewardship programs is essential for enhancing outcomes in cancer patients.