Background/aim:It wasaimed herein to investigate coronavirus disease (COVID-19) in cancer patients and compare hematological and solid organ cancer patients in terms of the course and outcome of this disease. Materials and methods:Data from cancer patients with laboratory-confirmed COVID-19 infection were analyzed retrospectively. Risk factors for poor prognosis and the effect of vaccination on the clinical outcomes of the patients were evaluated. Results:A total of 403 cancer patients who were diagnosed with COVID-19 between March 1st, 2021, and November 30th, 2022, were included, of whom 329 (81.6%) had solid and 74 (18.4%) had hematological cancers. Hospitalization and intensive care unit (ICU) admission rates were significantly higher in the hematological cancer patients compared to the solid organ cancer patients (73.0% vs. 35.9%, p< 0.001 and 25.7% vs. 14.0%, p= 0.013, respectively). The COVID-19-related case fatality rate (CFR) was defined as 15.4%, and it was higher in the hematologicalcancer patientsthan inthe solid organ cancer patients (23.0% vs. 13.7%, p= 0.045) and was higher in patients with metastatic/advanced disease compared to the other cancer stages (p< 0.001). In the solid organ cancergroup, hospitalization, ICU admission, and the COVID-19 CFR were higher in patients with respiratory and genitourinary cancers (p< 0.001). A total of 288 (71.8%) patients had receivedCOVID-19 vaccination; 164 (56.94%) had≤2 doses and 124 (43.06%) had≥3 doses.The hospitalization rate was higher in patients with ≤2 doses of vaccine compared to those with ≥3 doses (48.2% vs. 29.8%,p= 0.002). Patients with COVID-19- related death had higher levels of leucocyte, neutrophil, D-dimer, troponin, C-reactive protein (CRP), procalcitonin, and ferritin and lower levels of lymphocyte than the survivors. In the logistic regression analysis,the risk of COVID-19-related mortality was higher in the hematological cancer patients(OR:1.726), those who were male (OR:1.757), and with the Pre-Delta/Delta variants (OR:1.817). Conclusion:This study revealed that there is an increased risk of COVID-19-related serious events (hospitalization, ICU admission, or death) in patients with hematological cancerscompared with those who have solid organ cancers. It wasalso show cine is more protective against severe illness and the need for hospitalization than ≤2 doses.

Background/Objectives: In multiple myeloma, extramedullary involvement confers poor prognosis. Extramedullary involvement in multiple myeloma may manifest at the time of diagnosis or during a relapse, and it represents a severe condition. Patients with bone involvement are referred to as EM-B, while those with soft tissue involvement are referred to as EM-S. Although various studies have been conducted, the number of studies that categorize extramedullary involvement and examine the effects of flow cytometry, treatment, and genetic findings on prognosis is quite limited. We aimed to contribute to the literature by addressing this gap. Methods: In our study, we retrospectively examined the data of 281 patients followed at our center between 2011 and 2023. Clinical/laboratory data and flow cytometry profiles were collected. Survival was analyzed using Kaplan–Meier and Cox models; logistic regression was used for categorical variables. Hazard ratios (HRs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated; p-values were reported to three decimals. Results: Extramedullary involvement was absent in 134 (47.7%) patients, while involvement was detected in 147 (52.3%) patients. The median age of the patients was 60 years, and the median follow-up period was 35.4 months. No association was found between CD56 expression on plasma cells, higher Revised Multiple Myeloma International Staging System (R-ISS) score, and extramedullary involvement. Overall survival (OS) was found to be significantly lower in patients with extramedullary involvement. Conclusions: The findings of our study are consistent with many studies in the literature, supporting the finding that survival rates are lower in myeloma patients with extramedullary involvement. Further studies are needed to elucidate the pathogenesis in patients with extramedullary involvement in multiple myeloma and to provide a basis for targeted therapies. Studies involving immunotherapy and cellular therapies may offer a new avenue for these patients.

Background: Erdheim Chester disease (ECD) is a rare disease with multisystemic involvement in the group of non-langerhans cell histiocytosis. Although nearly 100 years have passed since its definition, the number of cases reported all over the world is below 1000. In addition to the rarity of the disease, low awareness seems to play a role in this. Case presentation: 47-year-old white caucasian women patient who presented to our clinic with symptoms of weakness-fatigue as well as increasing pain in the knees and ptosis in the left eye. Result of the patient's bone biopsy, ECD was considered pathologically and BRAF V600E mutation was shown molecularly. After presenting the clinical, laboratory and other examination results of the case, the dramatic response seen with targeted therapy will be discussed. Conclusions: BRAF V600E mutation is frequently seen in ECD. Vemurafenib plays an active role in targeted therapy.

Background and Objectives: The use of cryopreserved hematopoietic cells in allogeneic hematopoietic cell transplantation (HCT) has become widespread all over the world and in our country, especially after the SARS-CoV-2 pandemic. This situation has increased the importance of the effect of cryopreservation on engraftment, the incidence of transplantation-related complications, and the survival of patients. This study aimed to compare the transplant results between the patient group receiving peripheral blood-derived cryopreserved cells and the patient group receiving fresh products in patients over the age of 18 who had hematological diseases and underwent allogeneic HCT. Materials and Methods: A total of 222 patients over the age of 18 with hematological diseases who underwent allogeneic HCT were included in the study. Neutrophil engraftment time, platelet engraftment time, disease-free survival, overall survival, graft versus host disease incidence, cytomegalovirus reactivation/infection and transplant-related mortality rates were retrospectively compared between the cryopreserved and fresh product groups. Results: No significant difference was found between the cryopreserved and fresh product groups in terms of median age, gender, body weight, hematological disease subtype, disease status before HCT, Sorror comorbidity index, blood group compatibility, and preparation regimen intensity. On the other hand, the haploidentical HCT count was higher in the fresh cell group. The number of CD34+ stem cells received by patients receiving cryopreserved products was lower than the number of CD34+ stem cells received by patients receiving fresh products. No significant difference was found between the cryopreserved and fresh product groups in terms of platelet and neutrophil engraftment time, engraftment failure rate, cytomegalovirus reactivation/infection rate in the first 100 days after HCT, development of graft versus host disease, transplant-related death, disease-free survival and overall survival. Conclusions: Cryopreservation and cell storage is very important in order to prevent complications such as delays in the patient's transplantation process due to donor-related problems, prolonged hospital stay, and related complications. When done properly, cryopreservation can produce HCT outcomes similar to those obtained with fresh products.

Background/Objectives: Hematopoietic stem cell (HSCs) mobilization from the bone marrow to the peripheral blood (PB) is a critical step in stem cell transplantation. Although some experimental studies have suggested that cholesterol levels may affect this process, the clinical relevance of lipid profiles in healthy donors remains unclear. This study aimed to investigate whether serum cholesterol parameters are associated with peripheral blood CD34+ HSC mobilization in healthy stem cell donors. Methods: A total of 251 healthy donors who underwent granulocyte colony-stimulating factor (G-CSF)-based mobilization were retrospectively analyzed. Peripheral blood CD34+ cell counts and yields (×106/kg) were recorded. Laboratory parameters, including total cholesterol, HDL-C, LDL-C, and triglyceride levels were evaluated. Correlations between mobilization outcomes and donor characteristics or laboratory findings were also assessed. Results: No significant association was found between serum lipid parameters (total cholesterol, LDL-C, HDL-C, triglycerides) and CD34+ cell mobilization or yield. However, white blood cell count, hemoglobin level, platelet count, absolute neutrophil count, and lymphocyte count showed significant positive associations with mobilization efficacy. In contrast, body mass index (BMI) was inversely correlated with CD34+ cell yield. Conclusions: Serum cholesterol levels do not appear to influence stem cell mobilization outcomes in healthy donors. Classical hematologic parameters remain reliable predictors of CD34+ cell yield. These findings suggest that cholesterol is not a suitable biomarker for predicting mobilization efficiency in this population group.