Activity of venetoclax in patients with relapsed or refractory chronic lymphocytic leukaemia: analysis of the VENICE-1 multicentre, open-label, single-arm, phase 3b trial

BACKGROUND

Most patients with chronic lymphocytic leukaemia progress after treatment or retreatment with targeted therapy or chemoimmunotherapy and have limited subsequent treatment options. Response levels to the single-agent venetoclax in the relapsed setting is unknown. We aimed to assess venetoclax activity in patients with or without previous B-cell receptor-associated kinase inhibitor (BCRi) treatment.

METHODS

This multicentre, open-label, single-arm, phase 3b trial (VENICE-1) assessed activity and safety of venetoclax monotherapy in adults with relapsed or refractory chronic lymphocytic leukaemia, stratified by previous exposure to a BCRi. Eligible participants were aged 18 years or older with previously treated relapsed or refractory chronic lymphocytic leukaemia. Presence of del(17p) or TP53 aberrations and previous BCRi treatment were permitted. Patients received 5-week ramp-up to 400 mg of oral venetoclax once daily and were treated for up to 108 weeks, with 2 years follow-up after discontinuation, or optional extended access. The primary activity endpoint was complete remission rate (complete remission or complete remission with incomplete marrow recovery) in BCRi-naive patients. Analyses used the intent-to-treat (ie, all enrolled patients, which coincided with those who received at least one dose of venetoclax). This study was registered with ClinicalTrials.gov, NCT02756611, and is complete.

FINDINGS

Between June 22, 2016, and March 11, 2022, we enrolled 258 patients with relapsed or refractory chronic lymphocytic leukaemia (180 [70%] were male; 252 [98%] were White; 191 were BCRi-naive and 67 were BCRi-pretreated). Median follow-up in the overall cohort was 49·5 months (IQR 47·2-54·1), 49·2 months (47·2-53·2) in the BCRi-naive group, and 49·7 months (47·4-54·3) in the BCRi-pretreated group. Of 191 BCRi-naive patients, 66 (35%; 95% CI 27·8-41·8) had complete remission or complete remission with incomplete marrow recovery. 18 (27%; 95% CI 16·8-39·1) of 67 patients in the BCRi-pretreated group had complete remission or complete remission with incomplete marrow recovery. Grade 3 or worse treatment-emergent adverse events were reported in 203 (79%) and serious adverse events were reported in 136 (53%) of 258 patients in the overall cohort. The most common treatment-emergent adverse event was neutropenia (96 [37%]) and the most common and serious adverse event was pneumonia (21 [8%]). There were 13 (5%) deaths reported due to adverse events; one of these deaths (autoimmune haemolytic anaemia) was possibly related to venetoclax. No new safety signals were identified.

INTERPRETATION

These data demonstrate deep and durable responses with venetoclax monotherapy in patients with relapsed or refractory chronic lymphocytic leukaemia, including BCRi-pretreated patients, suggesting that venetoclax monotherapy is an effective strategy for treating BCRi-naive and BCRi-pretreated patients.

FUNDING

AbbVie.

Eltrombopag for the Treatment of Poor Graft Function Following Haematopoietic Cell Transplantation: Real-Life Data

Background

Eltrombopag has an off-label indication for haematopoietic cell transplantation in patients experiencing delayed thrombocyte recovery and/or thrombocytopaenia.

Aims

To present our centre’s experience of using this agent not only for post- haematopoietic cell transplantation thrombocytopaenia but also for poor graft functioning in the post-haematopoietic cell transplantation setting.

Study Design

Retrospective cross-sectional study.

Methods

Thirty-nine patients who had persistent cytopaenia following haematopoietic cell transplantation and treated with eltrombopag at our centre between October 2011 and December 2021 were retrospectively identified. During this period, 9 (23.1%) and 30 (76.9%) patients who underwent allogeneic transplantations, respectively, received eltrombopag.

Results

The female-to-male ratio was 12:27, and the median transplant age was 49 (18-70) years. Eight (20.5%) patients had isolated thrombocytopaenia, 19 (49.4%) had bi-lineage cytopaenia and 12 (30.1%) had pancytopaenia. Patients received a median of 50 mg/day (25-150 mg/day) of eltrombopagfor a median duration of 82 (24-386) days. Nine (23.1%) patients had autologous haematopoietic cell transplantation, and 30 (76.9%) had allogeneic haematopoietic cell transplantation (14 unrelated, 9 sibling and 7 haploidentical). The median donor age was 32 (20-67) years. The median follow-up was 16.4 (1.8-84.3) months. The median pre-treatment platelet count was 11x10⁹/l (1-23), which increased to 41x10⁹/l (6-150). The median platelet count increment was 29.5x10⁹/l (p = 0.001). The pre-treatment median neutrophil count was 1.19x10⁹/l (0.39-5.1), which increased to 2.35 x10⁹/l (0.1-5.33) (p = 0.05), and the pre-treatment median haemoglobin was 8.3 (6.2-14) g/dl, which increased to 10 (6.2-14) g/dl (p = 0.001) with eltrombopag. No eltrombopag-related hepatotoxicity occurred; however, 1 (2.6%) patient failed to continue treatment because of two consecutive episodes of deep venous thrombosis. Six (15.4%) patients were unresponsive to eltrombopag and dependent on blood product transfusions. After a median time of 82 days, 61.5% of the patients discontinued eltrombopag successfully.

Conclusion

The results confirmed that eltrombopag could provide a rapid, sustained response in patients with poor graft functioning after haematopoietic cell transplantation. This finding is essential given the high rate of non-relapse mortality caused by poor graft functioning after haematopoietic cell transplantation.

Highlighting the Prognostic Importance of Measurable Residual Disease Among Acute Myeloid Leukemia Risk Factors

Objective:

The optimal timing of measurable residual disease (MRD) evaluation in acute myeloid leukemia (AML) patients has not been well defined yet. We aimed to investigate the impact of MRD in pre- and post-allogeneic hematopoietic stem cell transplantation (AHSCT) periods on prognostic parameters.

Materials and Methods:

Seventy-seven AML patients who underwent AHSCT in complete morphological remission were included. MRD analyses were performed by 10-color MFC and 10^-4 was defined as positive. Relapse risk and survival outcomes were assessed based on pre- and post-AHSCT MRD positivity.

Results:

The median age of the patients was 46 (range: 18-71) years, and 41 (53.2%) were male while 36 (46.8%) were female. The median follow-up after AHSCT was 12.2 months (range: 0.2-73.0). The 2-year overall survival (OS) in the entire cohort was 37.0%, with a significant difference between patients who were MRD-negative and MRD-positive before AHSCT, estimated as 63.0% versus 16.0%, respectively (p=0.005). MRD positivity at +28 days after AHSCT was also associated with significantly inferior 2-year OS when compared to MRD negativity (p=0.03). The risk of relapse at 1 year was 2.4 times higher (95% confidence interval: 1.1-5.6; p=0.04) in the pre-AHSCT MRD-positive group when compared to the MRD-negative group regardless of other transplant-related factors, including pre-AHSCT disease status (i.e., complete remission 1 and 2). Event-free survival (EFS) was significantly shorter in patients who were pre-AHSCT MRD-positive (p=0.016). Post-AHSCT MRD positivity was also related to an increased relapse risk. OS and EFS were significantly inferior among MRD-positive patients at +28 days after AHSCT (p=0.03 and p=0.019).

Conclusion:

Our results indicate the importance of MRD before and after AHSCT independently of other factors.

HEV seroprevalence in blood donors in Turkey by two commercial total anti-HEV Ab ELISA kits

Previous hepatitis E virus (HEV) seroprevalence studies in Turkey have shown high variabilities, leading to conflicting results. We aimed to re-evaluate HEV seroprevalence among blood donors in Turkey using the Wantai (Beijing, China) and the Dia.Pro (Milan, Italy) total anti-HEV antibody (Ab) enzyme-linked immunosorbent assay (ELISA) kits and compare their performances and to investigate the presence of HEV RNA in blood donors. Serum total anti-HEV antibodies were determined in a total of 2011 volunteer blood donor samples collected from different regions of Turkey (807 from Ankara, 243 from Kayseri, 284 from İzmir, 200 from Malatya, 200 from Kahramanmaraş, and 277 from Van). HEV RNA was evaluated by a real-time polymerase chain reaction in a total of 272 anti-HEV seropositive samples. The country-wide HEV seroprevalence was calculated as 11.5% (Dia.Pro) and 12.2% (Wantai) with seropositivity rates of 12.0%-12.5% in Ankara, 7.4%-8.2% in Kayseri, 14.5%-15.5% in Malatya, 8.1%-8.8% in İzmir, 15.0%-16.0% in Kahramanmaraş, and 12.6%-13.4% in Van by Dia.Pro and Wantai kits, respectively. The lowest detectable Ab concentrations were 0.16 and 0.14 units/mL WHO, for the Dia.Pro and the Wantai assays, respectively, showing no significant difference between assays. HEV RNA was not detected in any of the anti-HEV seropositive samples. Compared with previous studies, HEV was shown to have a higher overall seroprevalence in Turkey. Despite its limitation, the current study represents the most comprehensive HEV seroprevalence study in Turkey performed with two different commercial ELISA assays with high sensitivities so far. Further investigation is required to determine HEV genotypes in Turkey.

Incomplete Antibodies May Reduce ABO Cross-Match Incompatibility: A Pilot Study

OBJECTIVE

Any erythrocyte transfusion among humans having type A or B blood groups is impossible due to antibodies causing fatal transfusion complications. A cross-match test is performed to prevent immune transfusion complications before transfusion. Our hypothesis is that the fragment antibody (Fab) part of the antibody (incomplete antibody) may be used to prevent an immune stimulus related to the complete antibody. Therefore, we designed a pilot study to evaluate the effectiveness of these incomplete antibodies using cross-match tests.

MATERIALS AND METHODS

Pepsin enzyme and staphylococcal protein A columns were used to cut anti-A and anti-B monoclonal antibodies and purify their Fab (2) fragments, respectively. An Rh-positive erythrocyte suspension with purified anti-A Fab (2) solution and B Rh-positive erythrocyte suspension with purified anti-B Fab (2) solution were combined correspondingly. Cross-match tests were performed by tube and gel centrifugation methods. The agglutination levels due to the anti-A and anti-B Fab (2) antibodies and their effects on the agglutination normally observed with complete antibodies were then measured.

RESULTS

No agglutination for the purified incomplete anti-A Fab (2) with A Rh+ erythrocyte and anti-B Fab (2) with B Rh+ erythrocyte combinations was observed in the tube cross-match tests. These agglutination levels were 1+ in two wells in the gel centrifugation cross-match tests. Fab (2)-treated erythrocytes were also resistant to the agglutination that normally occurs with complete antibodies.

CONCLUSION

We determined that the Fab (2) fragments of antibodies may not only be used to obtain a mild or negative reaction when compared to complete antibodies, but they might also be used for decreasing ABO incompatibility. Incomplete antibodies might be a therapeutic option in autoimmune hemolytic anemia and they may also be used in solid organ or hematopoietic stem cell transplantation. Therefore, we have planned an in vivo study to prove these in vitro findings.

Investigation of an algorithm for anti HCV EIA reactivity in blood donor screening in Turkey in the absence of nucleic acid amplification screening

PURPOSE

In this study we aimed to propose an algorithm for initial anti HCV EIA reactive blood donations in Turkey where nucleic acid amplification tests are not yet obligatory for donor screening.

METHODS

A total of 416 anti HCV screening test reactive donor samples collected from 13 blood centers from three cities in Turkey were tested in duplicate by Ortho HCV Ab Version 3.0 and Radim HCV Ab. All the repeat reactive samples were tested by INNO-LIA HCV Ab 3.0 or Chiron RIBA HCV 3.0 and Abbott Real Time HCV. Intra-assay correlations were calculated with Pearson r test. ROC analysis was used to study the relationship between EIA tests and the confirmatory tests.

RESULTS

The number of repeat reactive results with Ortho EIA were 221 (53.1%) whereas that of microEIA, 62 (14.9%). Confirmed positivity rate was 14.6% (33/226) by RIBA and 10.6% (24/226) by NAT. Reactive PCR results were predicted with 100% sensitivity and 95% specificity with S/CO levels of 8.1 with Ortho EIA and 3.4 with microEIA.

CONCLUSIONS

Repeat reactivity rates declined with a second HCV antibody assay. Samples repeat reactive with one HCV antibody test and negative with the other were all NAT negative. All the NAT reactive samples were RIBA positive. None of the RIBA indeterminate or negative samples were NAT reactive. Considering the threshold values for EIA kits determined by ROC analysis NAT was decided to be performed for the samples above the threshold value and a validated supplemental HCV antibody test for the samples below.

Subsequent malignancies after allogeneic hematopoietic stem cell transplantation

We evaluated 979 patients for the development of post-transplant lymphoproliferative disease (PTLD) and solid malignancies after allogeneic hematopoietic stem cell transplantations (allo-HSCT) as a late complication. We found 15 (1.5%) subsequent malignancies; three of these malignancies were PTLD, and twelve were solid tumors. The median time from allo-HSCT to the development of PTLD was 9 (3-20) months and that from allo-HSCT to the development of solid tumors was 93 (6-316) months. The cumulative incidence of evolving subsequent malignancy in patients was 1.3% (±0.5 SE) at 5 years and 3.9% (±1.2 SE) at 10 years. The cumulative incidence of developing subsequent malignancy in patients with benign hematological diseases as the transplant indication was 7.4%±4.2 SE at 5 years. More subsequent malignancy developed in patients having ≥1 year chronic graft-vs-host disease (GVHD; 3.7% in ≥1 year chronic GVHD and 0.7% in <1 year chronic GVHD patient groups, P=.002). Subsequent epithelial tumor risk was higher in ≥1 year chronic GVHD patients than <1 year (3.7% vs 0.1%, P<.001). In multivariate analysis, benign hematological diseases as transplant indication (RR: 5.6, CI 95%: 1.4-22.3, P=.015) and ≥1 year chronic GVHD (RR: 7.1, 95% CI: 2.3-22.5, P=.001) were associated with the development of subsequent malignancy.

Blinatumomab versus Chemotherapy for Advanced Acute Lymphoblastic Leukemia

BACKGROUND

Blinatumomab, a bispecific monoclonal antibody construct that enables CD3-positive T cells to recognize and eliminate CD19-positive acute lymphoblastic leukemia (ALL) blasts, was approved for use in patients with relapsed or refractory B-cell precursor ALL on the basis of single-group trials that showed efficacy and manageable toxic effects.

METHODS

In this multi-institutional phase 3 trial, we randomly assigned adults with heavily pretreated B-cell precursor ALL, in a 2:1 ratio, to receive either blinatumomab or standard-of-care chemotherapy. The primary end point was overall survival.

RESULTS

Of the 405 patients who were randomly assigned to receive blinatumomab (271 patients) or chemotherapy (134 patients), 376 patients received at least one dose. Overall survival was significantly longer in the blinatumomab group than in the chemotherapy group. The median overall survival was 7.7 months in the blinatumomab group and 4.0 months in the chemotherapy group (hazard ratio for death with blinatumomab vs. chemotherapy, 0.71; 95% confidence interval [CI], 0.55 to 0.93; P=0.01). Remission rates within 12 weeks after treatment initiation were significantly higher in the blinatumomab group than in the chemotherapy group, both with respect to complete remission with full hematologic recovery (34% vs. 16%, P<0.001) and with respect to complete remission with full, partial, or incomplete hematologic recovery (44% vs. 25%, P<0.001). Treatment with blinatumomab resulted in a higher rate of event-free survival than that with chemotherapy (6-month estimates, 31% vs. 12%; hazard ratio for an event of relapse after achieving a complete remission with full, partial, or incomplete hematologic recovery, or death, 0.55; 95% CI, 0.43 to 0.71; P<0.001), as well as a longer median duration of remission (7.3 vs. 4.6 months). A total of 24% of the patients in each treatment group underwent allogeneic stem-cell transplantation. Adverse events of grade 3 or higher were reported in 87% of the patients in the blinatumomab group and in 92% of the patients in the chemotherapy group.

CONCLUSIONS

Treatment with blinatumomab resulted in significantly longer overall survival than chemotherapy among adult patients with relapsed or refractory B-cell precursor ALL. (Funded by Amgen; TOWER ClinicalTrials.gov number, NCT02013167 .).

Allogeneic Transplantation in Chronic Myeloid Leukemia and the Effect of Tyrosine Kinase Inhibitors on Survival: A Quasi-Experimental Study

Objective:

Tyrosine kinase inhibitors (TKIs) have changed the indications for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in chronic myeloid leukemia (CML). Therefore, we aimed to evaluate the effect of TKIs on allo-HSCT in CML.

Materials and Methods:

In this quasi-experimental study, we compared patient, disease, and transplantation characteristics as well as allo-HSCT outcomes between the pre-TKI era (before 2002) and the post-TKI era (2002 and later) in patients with CML. A total of 193 allo-HSCTs were performed between 1989 and 2012.

Results:

Patients in the post-TKI era had more advanced disease (>chronic phase 1) at the time of transplant and more frequently received reduced-intensity conditioning compared to patients in the pre-TKI era. Relapse/progression occurred more frequently in the year ≥2002 group than in the year <2002 group (48% vs. 32% at 5 years, p=0.01); however, overall survival (OS) was similar in these two groups (5-year survival was 50.8% vs. 59.5%, respectively; p=0.3). TKIs (with donor lymphocyte infusions or alone) for treatment of relapse after allo-HSCT were available in the post-TKI era and were associated with improved OS. While the rates of hematologic remission at 3 months after allo-HSCT were similar between TKI eras, patients having remission had better disease-free survival (DFS) [relative risk (RR): 0.15, confidence interval (CI) 95%: 0.09-0.24, p<0.001] and OS (RR: 0.14, CI 95%: 0.09-0.23, p<0.001). Male allo-HSCT recipients had worse DFS (RR: 1.7, CI 95%: 1.2-2.5, p=0.007) and OS (RR: 1.7, CI 95%: 1.1-2.6, p=0.02) than females.

Conclusion:

TKIs are an effective option for the treatment of relapse after allo-HSCT in CML. Hematologic remission after allo-HSCT is also an important factor for survival in CML patients.

Chimeric Antigen Receptor T Cell Therapy in Hematology

It is well demonstrated that the immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation. Adoptive T cell transfer has been improved to be more specific and potent and to cause less off-target toxicity. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR) and chimeric antigen receptor (CAR) modified T cells. On 1 July 2014, the United States Food and Drug Administration granted ‘breakthrough therapy’ designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the benefits of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical and clinical studies, and the effectiveness and drawbacks of this strategy.

A Randomized Comparison of Hemoglobin Content-Based Versus Standard (Unit-Based) Red Blood Cell Transfusion Policy

Objective:

The hemoglobin (Hb) content of packed red blood cells (pRBCs) differs in standard volume units. The pRBC transfusions are based on the number of units routinely. We aimed to use pRBCs according to total Hb content and compare the rates of achieving the target Hb concentration levels with the current transfusion practice.

Materials and Methods:

Eighty-nine patients (55 males and 34 females) with median age of 46 years (range: 19-75) were enrolled, and of 178 transfusion episodes, 92 were randomized to the Hb content based-study group and 86 to the unit-based control group. Fifty-one patients were evaluated by 1 and rest of the patients by ≥2 episodes (median: 3; range: 1-7). Suitable pRBCs were detected by the Hemosoft Blood Banking Management & Information System. In the Hb content-based study group, to reduce the number of units, the required Hb was calculated by recipients’ height, weight, and Hb levels. When no appropriate units could be found within the inventory, the actual ordered number of units was sent to clinics, as was done for the control group.

Results:

In the study group totally, 38 units of pRBCs were transfused with a reduction of 19.8% (38/192) from the original order. The success of finding the matched Hb content was statistically increased with low weight and height and high pRBC storage. The Hb content of transfused pRBC units was significantly higher in the study group than the control group. The ratio of achieving the target Hb level was statistically similar in the control and study group (p=0.125), the successful and unsuccessful group (p=0.325), and the control and unsuccessful group (p=0.438). The relation between the shelf-life of the pRBC units and the rate of achieving the target Hb level was found to be similar between groups (p=0.782).

Conclusion:

The number of pRBC transfusions can be minimized since we clearly demonstrated that the efficacy of Hb content-based transfusion is similar to that of unit-based transfusion.

A Quasi-Experimental Study Analyzing the Effectiveness of Portable High-Efficiency Particulate Absorption Filters in Preventing Infections in Hematology Patients during Construction

Objective:

The increased risk of infection for patients caused by construction and renovation near hematology inpatient clinics is a major concern. The use of high-efficiency particulate absorption (HEPA) filters can reduce the risk of infection. However, there is no standard protocol indicating the use of HEPA filters for patients with hematological malignancies, except for those who have undergone allogeneic hematopoietic stem cell transplantation. This quasi-experimental study was designed to measure the efficacy of HEPA filters in preventing infections during construction.

Materials and Methods:

Portable HEPA filters were placed in the rooms of patients undergoing treatment for hematological malignancies because of large-scale construction taking place near the hematology clinic. The rates of infection during the 6 months before and after the installation of the portable HEPA filters were compared. A total of 413 patients were treated during this 1-year period.

Results:

There were no significant differences in the antifungal prophylaxis and treatment regimens between the groups. The rates of infections, clinically documented infections, and invasive fungal infections decreased in all of the patients following the installation of the HEPA filters. When analyzed separately, the rates of invasive fungal infections were similar before and after the installation of HEPA filters in patients who had no neutropenia or long neutropenia duration. HEPA filters were significantly protective against infection when installed in the rooms of patients with acute lymphocytic leukemia, patients who were undergoing consolidation treatment, and patients who were neutropenic for 1-14 days.

Conclusion:

Despite the advent of construction and the summer season, during which environmental Aspergillus contamination is more prevalent, no patient or patient subgroup experienced an increase in fungal infections following the installation of HEPA filters. The protective effect of HEPA filters against infection was more pronounced in patients with acute lymphocytic leukemia, patients undergoing consolidation therapy, and patients with moderate neutropenia.

Vanishing bile duct syndrome after allogeneic bone marrow transplantation: is it the end of the road?

In this paper, we report the case of a 19-year-old male patient who presented with lymphoblastic phase of chronic myeloid leukemia and received an allogeneic bone marrow transplant from his cousin. The patient experienced severe, steroid-refractory acute graft versus-host disease of skin, gastrointestinal tract and liver that required further immunosuppression. However, hepatic graft-versus-host disease was complicated with vanishing bile duct syndrome, characterized by progressive destruction of small intrahepatic bile ducts, which was refractory to all available therapies and eventually led to end-stage liver disease. The pathogenesis and treatment of graft-versus-host disease after allogeneic hematopoietic cell transplantation is discussed with an emphasis on liver transplantation for intractable hepatic graft-versus-host disease.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) in acute myeloblastic leukemia (AML): A single center experience

OBJECTIVE

We retrospectively analyzed the impact of pre- and post-transplant variables on the outcome of transplanta¬tion in 145 consecutive patients with acute myeloblastic leukemia (AML) allografted from their HLA-identical siblings in our single center cohort.

RESULTS

The stem cell source used was bone marrow (BM) (36.6%) or peripheral blood (PB) (63.4%). Both neutrophil and platelet engraftments were observed on the median 14th day. Engraftment was faster in the PB group than in the BM group (p<0.0001). Severe acute graft versus host disease (aGvHD) was observed in 27.9% of the patients while chronic (c)GvHD developed in 61.2%. The use of PB was associated with more severe aGvHD. Estimated leukemia-free survival (LFS) and overall survival (OS) at 10 years were 43.4%±5.2% and 52.7%±4.6%, respectively.

CONCLUSION

Both in univariate and multivariate analyses for LFS and OS, remission status at transplant and the presence of aGvHD were independent risk factors.

Autologous Platelet Collection and Storage to Support Thrombocytopenia in a Leukemia Patient with Platelet Alloimmunization Undergoing Chemotherapy

Platelet alloimmunization occurs frequently in multitransfused patients. To prevent the posttransfusion complications donor white blood cells (WBCs) must be removed from the platelet concentrates (PC). But sometimes the centrifugation and filtration of WBC is not enough and in such conditions HLA-matched PC are recommended. Cryopreservation of autologous PC offers a potential solution to this problem. We investigated the feasibility of supporting the aplastic period after chemotherapy in a 54-year-old leukemia patient with autologous platelets collected by apheresis and cryopreserved. Our case report demonstrates that autologous apheresis platelet transfusion might be a feasible approach to high risk patients with bleeding tendencies.

The Role of ABO Incompatibility in Allogeneic Peripheral Blood Stem Cell Transplant

ABO incompatibility is not a contraindication for allogeneic bone marrow transplantation, but this procedure requires an extra effort for erythrocyte or plasma depletion in certain well established conditions. Some acute or delayed immunohematological complications such as acute or chronic hemolysis and pure red cell aplasia may be encountered. In this study the outcome and transplant related complications of ABO incompatible and identical cases, who have received allogeneic peripheral blood stem cells from their HLA identical siblings were compared with each other. Ninety-one patients (CML 36, AML 37, other 18) were analyzed retrospectively including 51 (60.4%) ABO identical patients and 36 (39.6%) ABO mismatched (MM) patients, who have a bi-directional MM (n= 5), major MM (n= 16), minor MM (n= 9) and Rh MM (n= 6). Median follow up was 13 (0.5-43.0) months. We did not observed any significant differences between two groups (identical vs non-identical) in terms of acute hemolysis preceding stem cell infusion, peritransplant transfusion demand, acute- and chronic graft versus host disease. There was no change in estimated disease free survival and overall survival durations. We did not observed any influence of ABO/Rh incompatibility on short term outcome in allogeneic peripheral blood stem cell transplantation in our series and did not recommend further manipulation of the infused stem cells.