Undergoing Bone Marrow Transplantation Research Articles

Evaluation of hypersensitivity reactions to cancer chemotherapeutic agents in pediatric patients

BackgroundHypersensitivity reactions (HSRs) to chemotherapeutic agents have been increasingly documented. ObjectiveThe aim of this study was to investigate HSRs due to chemotherapeutics agents in childhood. MethodsFrom January 2007 to June 2019, the patients who were treated for neoplastic diseases in our hospital were evaluated. Patients who developed a HSR to a chemotherapeutic agent were included. ResultsFifty-seven patients with 65 reactions (60% anaphylaxis) were evaluated. Escherichia coli asparaginase was responsible for 38 (58.5%) of these 65 reactions. The other agents were polyethylene glycol (PEG)–asparaginase (n = 11), etoposide (n = 7), methotrexate (n = 4), carboplatin (n = 4), and procarbazine (n = 1). Of the 38 patients who had a reaction to E coli–asparaginase, 33 patients received alternative treatment (PEG-asparaginase or Erwinia asparaginase), 3 patients continued with desensitization, and 2 patients underwent bone marrow transplantation. Five patients who had an initial reaction to PEG-asparaginase continued their treatment with Erwinia asparaginase or E coli asparaginase uneventfully. Of 7 patients who had a reaction to etoposide (4 had anaphylaxis), 3 patients continued with desensitization, and 2 patients used the drug with premedication and prolonged infusion. Two patients had anaphylaxis with methotrexate. Treatment was continued with desensitization in 1 patient and methotrexate treatment was discontinued in the other patient. Of the 4 patients with carboplatin hypersensitivity, 2 had anaphylaxis. Desensitization was performed in 2 patients. One patient had procarbazine HSR, drug was given with premedication. ConclusionAmong all chemotherapeutic agents reviewed in our study that caused HSRs, asparaginase was the most common culprit agent in children. Most of reactions are immediate type. Many of the patients can take their treatment by drug replacement or desensitization.

Assessing Physical Function and Fatigue in Patients Selected to Undergo Bone Marrow Transplant.

Introduction The assessment of baseline physical function should be an important and integral component in the selection of patients to undergo a bone marrow transplant. This assessment can establish a baseline level of function that can be tracked as the person undergoes cancer treatment as well as during the survivorship period. It can also be used to identify physical impairments early that can subsequently be treated rehabilitative interventions to minimize activity limitations and participation restrictions. Simple tests are available and can be useful in clinical settings. Objectives The aim of this work is to share one center's experience in the collection and analysis of data pertinent to physical function in patients referred for pre-bone marrow transplant evaluation. Methods Retrospective chart review of patients referred for an initial consultation in a cancer rehabilitation clinic in a cancer institute. The medical charts of 29 patients selected to undergo bone marrow transplant (AML/ALL-4, Lymphoma-11 and myeloma 14) were reviewed. Mean age was 55. Gender: 12 female and 17 male. The following information was reviewed: a) Patient Reported Outcome Measure Information System (PROMIS) Physical Function Short form and Fatigue short form b) Timed up and Go (TUG) test c) Sit to stand in 30 seconds test (STS-30) d) Grip Strength (in Kg)using a hand held dynamometer and e) 4 stage balance test. Values obtained during clinic visits were compared to available normative data for factors such as age and gender. These tools were selected because they are validated instruments that are easily collected in a physician's clinic. Results Based on the PROMIS Physical Function score results, 9/28 pre-BMT (32%) had an impaired physical function. Based on the PROMIS-Fatigue score results, 6/28 pre-BMT patients (21%) complained of significant fatigue. STS-30 results: 13/28 (46.4%) patients had normal scores for age and gender; 15/28 (53.6%) participants had abnormal scores for age and gender. Score for 1 participant was not available. Grip strength results: 17/27 (63%) patients had normal values for age and gender, 10/27 (37%) patients had normal values for age and gender. Scores for 2 participants were not available. 4 stage balance test: 28/29 (96.6%) participants had a normal balance and 1/29 (3.4%) participants had an impaired balance. Conclusion Assessment of physical function should be an integral part of the evaluation of patients prior to bone marrow transplant. Several instruments can be easily incorporated into a clinical setting and the information gathered can be very useful in directing need for additional interventions and can also serve as a baseline. Grip strength and sit to stand tests are easy to perform and can be very useful in assessment of physical function.

Reduction in Routine Labs in the Inpatient BMT Setting: A Quality Improvement Initiative

<h3>Introduction</h3> Common labs, such as a daily complete blood count (CBC) or a daily basic metabolic panel (BMP), represent possible healthcare waste. The Global Aim of this quality improvement initiative was to reduce lab draws and overall healthcare costs through implementation of routine standardized lab practices for patients undergoing bone marrow transplant (BMT). Our Smart Aim was to decrease the median number of labs per hospitalized BMT patient per week by 10%. <h3>Methods</h3> Using the Model for Improvement, we identified several opportunities to decrease the frequency of routine labs. This included: 1) daily CBC and BMP were obtained on all patients from the start of the preparative regimen through discharge; 2) daily CBC and BMP were obtained on all patients upon readmission; 3) there was no standardized process to clinically evaluate lab frequency. We addressed these opportunities through Plan-Do-Study-Act (PDSA) testing. Interventions included: 1) implementing a mindful mechanism to determine lab frequency prior to the start of chemotherapy; 2) weekly scheduled assessment and discussion of lab frequency during rounds; 3) implementation of a readmission order set with decreased frequency of lab monitoring. Finally, we used standardized run charts to measure the impact of the interventions. <h3>Results</h3> From January 2019 to June 2019, the median number of weekly labs for patients admitted to the BMT unit decreased from 54 to 49. These gains have been sustained for an additional four months. <h3>Discussion</h3> Using standardized processes, we demonstrated a substantial decrease in the number of weekly labs obtained on patients admitted to the BMT unit. We believe these interventions and measurements can be used in all transplant centers and can influence outcomes.

Comparison of Function, Fatigue, Frailty in Patients with Malignant Hematology, Pre-Bone Marrow Transplant and Solid Tumors.

Introduction Impaired physical function, fatigue and frailty are commonly seen in patients undergoing cancer treatment as well as in cancer survivors. These can have a significant adverse effect on the quality of life of the affected individuals. Objectives To compare the prevalence of impairment of physical function, fatigue and frailty in three populations of cancer patients-malignant hematology, patients with malignant hematology (MH) selected to undergo bone marrow transplant (pre-BMT) and patients with solid tumors (ST). Methods Retrospective chart review of patients referred to a cancer rehabilitation clinic in a cancer institute. The medical charts of 355 patients with ST (Breast-264; prostate-20; lung- 34 and GI- 37), 48 patients with MH (AML/ALL-5, Lymphoma-23, Myeloma-18, other:2) and 29 patients pre-BMT (AML/ALL-4, Lymphoma-11 and myeloma 14) were reviewed. Mean age: ST-67, MH-67 and Pre-BMT-55. Gender: ST-305 female; 50male; MH-25 female and 23 male; Pre-BMT-12 female and 17 male. Information reviewed: a) Patient Reported Outcome Measure Information System (PROMIS) Physical Function short form and Fatigue short form b) Timed Up and Go (TUG) test c) Sit to stand in 30 seconds test d) Grip Strength (in Kg), e) weight loss. Frailty or pre-frailty was determined by using modified Fried frailty criteria. Elements included: a) exhaustion (PROMIS-Fatigue score) b) low physical activity (PROMIS-Physical Function score) c) slowness (TUG) d) weakness (Grip strength) and e) weight loss. If person had 3/5 elements present, they were considered and if 1-2/5 elements were present, they were considered pre-frail. Results Impaired physical function: 198/348 of ST patients (57% ), 35/48 of MH patients (72.9% ) and 9/28 pre-BMT ( 32% ). Significant Fatigue: 122/349 ST patients (35%), 24/46 of MH patients (52%) and 6/28 pre-BMT patients (21%). Frail and Pre-frail: 137/315 (44%) of ST patients met pre-frail criteria and 143/315 (45%) ST patients met frail criteria. 14/43 (33%) of MH patients were pre-frail and 27/43 (63%) MH patients were frail. 16/28 ( 57% ) of pre-BMT patients were pre-frail and 7/28 ( 25% ) pre-BMT patients were frail. Conclusion Malignant hematology patients are more likely to have impaired self-reported physical function, significant fatigue and be frail compared to patients selected to undergo BMT and those with solid tumors at time of initial presentation to a cancer rehabilitation clinic. Physical impairments, fatigue and frailty should be identified early at time of diagnosis, during active treatment and during survivorship period and appropriate rehabilitation interventions initiated to maximize function and quality of life.

Female reproductive potential after oncological treatment: a rare case report of acute myeloid leukemia in monozygotic twin sisters with literature review

BackgroundAcute myeloid leukemia (AML) in monozygotic twins is a rare event and, until now, only a few cases have been reported. Due to improved oncological treatment and cancer survival rates, quality of life considerations post-treatment have become an important aspect in the treatment regime. The ability to have their own biological children is considered one of the most important indicators of quality of life by cancer survivors. As fertility following oncological treatment is often impaired, fertility preservation methods should be offered to these patients prior to the treatment. Here, we present a very rare case in which we can in vivo observe the impact of oncological treatment on female fertility when applied before and after puberty.Case presentationThis is a very rare case of concordant AML in monozygotic twin sisters. Twin A became sick at the age of 21 months. She was treated with cytostatic medications and then underwent bone marrow transplantation (BMT), the donor being her twin sister B. After 27 years, she is disease free and has regular periods. After trying to conceive for 4 years, she was seen by an infertility specialist. She underwent hysteroscopic uterine septum removal and laparoscopic enucleation of bilateral paraovarian cysts. Following those procedures, she immediately conceived naturally. Twin B became sick at 15 years of age. She was treated with chemotherapy and cranial radiation and relapsed after 10 years. She then received chemotherapy and had a BMT. Until relapse, she had normal menstrual cycles. After the second treatment she became amenorrhoeic and is now part of an oocyte donation program.ConclusionsThis is a case of AML in monozygotic twins who, after treatment, have completely different reproductive potential. They both received oncological treatment, and one of them conceived conceived naturally while the other suffered premature ovarian failure and is not able to have a biological child. Based on the outcome of this case, it appears that the pre-pubertal state truly serves as protection against ovarian failure.

Resiliency in Older Adults Undergoing Bone Marrow Transplant

Resiliency in Older Adults Undergoing Bone Marrow Transplant

Metcalf Lecture Award: Applying niche biology to engineer T-cell regenerative therapies

The processes generating cells of adaptive immunity render them less amenable to the single cytokine signals used so effectively to regenerate myeloid cells. T-cell neogenesis begins in the bone marrow, where specific sets of late osteolineage cells govern the specification of hematopoietic cells capable of migrating to the thymus where differentiation is completed. Osteocalcin-expressing bone marrow stromal cells producing Dll4 serve as a progenitor niche enabling this T-competent cell production. Biocompatible alginate-based cryogels containing bone morphogenetic proteins (BMP-2) and the Notch ligand Dll4 were engineered to recapitulate the endogenous niche. These cryogels are highly pliable and can be injected under the skin of animals undergoing bone marrow transplantation. The result in mice is an ectopic niche fostering T-competent progenitor generation that results in improved T-cell numbers and receptor diversity. The recipients can generate neoantigen vaccine responses while having improved tolerance manifest by reduced graft-versus-host disease upon allogeneic transplant. Through emerging details of niches in the bone marrow, therapeutics more complex than those necessary for myeloid reconstitution are possible. Niche biology-guided bioengineered design offers the possibility of regenerative therapies for T lymphoid cells.

Persistence of PNH Clones over Time: Insights from the Mid-Term Analysis of the French Nation-Wide Multicenter Prospective Observational Study

Introduction: Since the publication of the International Guidelines (Borowitz, 2010; Illingworth, 2018), no study has assessed the long-term evolution of paroxysmal nocturnal hemoglobinuria (PNH) clones using high-resolution flow cytometry. The sole evaluation, performed by Sugimori et al, using a 2-color flow cytometry test, showed the disappearance of PNH clones in 24% of patients with bone marrow (BM) failure over 5 years (Sugimori, 2009). A diagnostic practice harmonization using high-resolution flow cytometry has spread in France since 2013 through an on-going inter-laboratory comparison program (Debliquis, 2015). Thus, our HPNAFC group has been able to initiate a French nation-wide multicenter prospective observational study. Objective: We aimed to assess the evolution of PNH clones over a long term period using mostly high sensitivity test, which is required for minor clone assessment, with validated flow cytometry data. Methods: All patients of any age with a PNH clone or GPI-deficient cells ≥0.01%, newly- or previously-diagnosed, detected in France from February 29th 2016, could be included in this Observatory, provided that the center had validated a PNH flow cytometry quality control. For each patient, the baseline assessment was always considered as the initial PNH clone detection, even if it occurred before the initiation of the Observatory. Thus, this strategy allowed the collection of cases with long-term follow-up. Referent cytometrist of each center included patients in the e-CRF available on the HPNAFC website providing clinical and biological information as well as flow cytometry raw data files. This study was approved by the national research ethics board. Results: As of July 15th 2019, 48 participating flow cytometry laboratories across France have enrolled 356 patients with a PNH clone or GPI-deficient cells ≥ 0.01%. All cases have been carefully reviewed by the 2 principal investigators, who both thoroughly re-examined flow cytometry data and the e-CRF filling that led to the update of roughly one third of the submitted files. This enabled the validation of 200 patients at diagnosis, the remaining 156 being ongoing. One hundred and three of the 200 validated patients displayed at least one follow-up point (more than 3 months apart from the diagnosis) with a clone size determined at diagnosis (see flow chart figure 1A). For 8/103 patients, exchanges with centers are still ongoing. Thus, we were able to assess the evolution of PNH clones of 95 patients with 2 [range: 1-8] follow-up points over a period of 4.1 [0.3-14.2] years, corresponding to 200 validated follow-up points. The patient median age at diagnosis was 40 years old [10-85] with 3 pediatric cases (&lt;18y) and a M/F sex ratio of 0.86. Diagnoses were made between 2003 and 2018 with clinical information available in 97% of cases: 19 patients (20%) had hemolytic anemia and most patients (n=73, 77%) displayed BM failure including aplastic anemia (n=62), myelodysplastic syndrome (n=7) and unexplained cytopenia(s) (n=4). No case of thrombosis was included. All patients with hemolytic anemia showed an increasing clone size over time including the two who were not treated with eculizumab (Figure 1B; median size at diagnosis on neutrophils: 81.3% vs median size over 5 years: 96.3%). The median clone size at diagnosis for patients with BM failure was 1.5% on neutrophils with a very wide range [0.01-97.87], almost half of them being less than 1%. When comparing the diagnosis point with the latest follow-up point, PNH clone size increased in 37 patients, decreased in 16 of them and remained stable in 20 cases (Figure 1C, D). Nine of the 37 patients reached a PNH clone size above 50% and 4 of them received a treatment by eculizumab in a median delay of 5 years [1.5-6.0]. Interestingly, no patient showed spontaneous disappearance of PNH clones, pending the use of a high-resolution flow cytometry test. The only five patients with undetectable PNH clones (Figure 1D, red lines) were those who underwent BM transplantation. Conclusion: This multicenter study based on robust flow cytometry analysis showed no disappearance of PNH clones, including minor ones, over a long period of time, regardless of the clinical manifestations, except for patients who underwent BM transplantation. Moreover, PNH clone size increased in half of patients with BM failure, justifying a long term PNH clone size monitoring, even in these patients. Figure 1 Disclosures Le Garff-Tavernier: Alexion: Consultancy, Honoraria. Pruvot Debliquis:Alexion: Honoraria; Takeda: Honoraria; Pfizer: Honoraria; Gilead: Honoraria; Genzyme: Honoraria. Socie:Alexion: Consultancy. Peffault de Latour:Alexion: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Amgen: Research Funding. Drenou:Alexion: Consultancy, Honoraria. Wagner Ballon:Alexion: Consultancy, Honoraria.

Transformation from Indolent Primary Cutaneous Marginal Zone Lymphoma to Aggressive Primary Cutaneous Diffuse Large B-Cell Lymphoma: A Rare Case and Review of the Literature

Introduction Primary cutaneous B-cell lymphomas (PCBCLs) arise within the skin without evidence of extracutaneous involvement at the time of diagnosis. The incidence of PCBCL is rare, and PCBCLs are less common than primary cutaneous T-cell lymphomas. There are three subgroups of PCBCL: primary cutaneous marginal zone lymphoma (PCMZL), primary cutaneous follicle-cell lymphoma (PCFCL), and primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT). The 5-year survival rates of the former two subtypes exceed 90%, whereas PCDLBCL-LT is approximately 50% (Wilcox 2015). We describe a rare case of indolent PCMZL transforming into the more aggressive PCDLBCL-LT as well as a review of literature and case series. Case A 62-year-old man with history of PCMZL refractory to external beam radiation and rituximab chemotherapy presented with a two-month history of an enlarging rash and three nodules on his left leg. On physical exam, two violaceous, infiltrative plaques with distinct borders were present on the left leg, resembling his past PCMZL. Three new lesions were described as deep-seated 2 cm erythematous nodules (Fig 1). Histologic review of the new nodules revealed a diffuse, dermal-based atypical lymphoid infiltrate extending from the papillary dermis into the subcutis. The atypical lymphoid cells contained mostly round nuclei, vesicular chromatin, and prominent nucleoli consistent with an immunoblastic and centroblastic morphology (Fig 2). They expressed B-cell markers such as CD79a and CD19, and were negative for CD20 most likely due to prior treatment with rituximab. Immunohistochemistry demonstrated positivity for Bcl-2 and MUM1. Discussion Primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT) is a rare and aggressive B-cell lymphoma. This subtype is positive for CD20 and CD79, negative for CD5 and CD10, and strongly positive for Bcl-2 and MUM1. It has the gene expression profile of the ABC subtype. A nodule on the lower leg is an ominous sign given this subtype's predilection for lower extremities. This subtype affects the elderly as opposed to the indolent subtypes that arise in middle age (Willemze 2005). Prognosticating PCDLBCL-LT is challenging, as survival rates vary from 40 to 70% (Willemze 2005). Additionally, the aggressive nature of PCDLBCL-LT confers use of more aggressive, systemic chemotherapy regimens. Rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (R-CHOP) chemotherapy followed by external beam irradiation is recommended, though no large prospective clinical trials have been performed to date. If lesions remain refractory to R-CHOP, the treatment goal should be redirected to treat as a refractory systemic diffuse large B-cell lymphoma which may require bone marrow transplant or targeted agents with known activity in the ABC subtype such as lenalidomide or ibrutinib. Transformation from PCMZL to PCDLBCL-LT is a rare event and has only been described in 2 case series (Table 1). In our review of the prior cases, the age group was heterogenous ranging from 29 years-old to 80 years-old. There was no consensus treatment, however, the majority of patients did receive at least CHOP-based regimen. Survival ranged from 24 months to 180 months, showing the heterogeneity of the disease process. In our patient, he underwent R-CHOP but progressed and then received salvage R-ICE with CR. He then underwent bone marrow transplantation but unfortunately had recurrence 36 days post-transplantation, proven PCDLBCL-LT, and he died 161 days following his allogeneic transplant. Conclusion Although PCMZL and PCFCL frequently recur despite treatment, transformation to PCDLBCL-LT is unusual. To date, transformation from PCMZL to PCDLBCL-LT has been described rarely in the literature (Table 1). PCMZL is indolent and is treated with external beam radiation therapy or surgical excision with excellent prognosis, the aggressive PCDLBCL-LT subtype has a poor outcome and requires systemic chemotherapy. Because of the vast difference in prognosis and treatment between PCMZL and PCDLBCL-LT, early recognition and exhaustive work-up is beneficial to the patient. Considering this transformation is both rare and diagnostically challenging, clinicians should have heightened concern for new nodular lesions in the setting of recurrent indolent primary cutaneous B-cell lymphomas. Disclosures Yazbeck: Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead Sciences: Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees.

Impact of Different Doses of Fludarabine in Fludarabine-Based Conditioning Regimen for Unrelated Bone Marrow Transplantation

Background: The purine analog fludarabine (Flu) is recognized as an agent having strong immunosuppressive effects and plays a central role in reduced-intensity conditioning (RIC) and myeloablative reduced-toxicity conditioning (RTC) regimens because of limited nonhematologic toxicities. Combinations of Flu and busulfan (Bu) (FB group) or melphalan (Mel) (FM group) are the commonly used as RIC and RTC regimens. Flu inhibits lymphocyte proliferation, induces apoptosis of hematologic malignant cells and has a synergistic tumor-killing effect with alkylating agents such as Bu and Mel. Few reports assess the impact of different dose of Flu on the clinical outcome. In this study, to compare the impact of Flu doses in RIC or RTC, we retrospectively analyzed clinical outcomes in patients who received FB or FM conditioning by using nationwide registration data of Japan Society for Hematopoietic Cell Transplantation. Method: Patients aged 16 years of older with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, chronic myeloid leukemia and malignant lymphoma, who received FB or FM conditioning regimen, and who underwent bone marrow transplantation from an unrelated donor between 2007 and 2016 were included in this study. We excluded patients who received oral Bu. Also, patients who had renal dysfunction in Hematopoietic Cell Transplantation-Comorbidity Index was excluded because Flu dose needs an adjustment due to renal function. As a result, 2809 patients were included in this study. All transplantation data in the present study were obtained from the Transplant Registry Unified Management Program (TRUMP), which included clinical data of hematopoietic cell transplantation performed in Japan. Result: In the FB group (n=1647), high-dose Flu (180 mg/m2; HFB) and low-dose Flu (150/125 mg/m2; LFB) were used in 1334 and 313 patients, respectively. The probabilities of 3-year OS and PFS in the HFB group were significantly higher than that in the LFB group (49% vs 38%, P&lt;0.001; 44% vs 35%, P=0.007). The cumulative incidences of relapse at 3 years were 30.4% and 36.6% (P=0.058), and NRM at 3 years were 25.1% and 28.1% (P=0.24) in the HFB and LFB groups, respectively. In multivariate analysis for OS and relapse, Flu doses was identified as an independent prognostic factor (HR 0.82, P=0.03; HR 0.8, P=0.043). In the FM group (n=1162), high-dose Flu (180 mg/m2; HFM) and low-dose Flu (150/125 mg/m2; LFM) were used in 118 and 1044 patients, respectively. There was no significant difference in the OS, relapse and NRM rates between HFM and LFM (at 3 years, 51.4% vs 48.5%, P=0.596; 22.4% vs 27.0%, P=0.362; 30.7% vs 30.3%, P=0.783). Conclusion: In this large study, we suggested that high-dose Flu was associated with favorable outcome in the FB group, but not in the FM group. Prospective studies and further investigations are needed to clarify the benefit of high-dose Flu in the setting of FB regimen. Disclosures Ozawa: Kyowa-Hakko Kirin: Honoraria; Astellas Pharma Inc.: Honoraria; Pfizer Japan Inc.: Honoraria; Novartis: Honoraria. Kanda:Daiichi Sankyo Company: Honoraria; Bristol-Meyers Squib: Honoraria; Celgene: Honoraria; MSD: Honoraria; JCR Pharmaceuticals: Honoraria; Takeda: Honoraria; Otsuka: Honoraria; Kyowa Hakko Kirin: Honoraria; Chugai: Honoraria; Astellas: Honoraria; Novartis: Honoraria; NextGeM Incorporation: Patents &amp; Royalties: 2019-011392. Atsuta:Kyowa Kirin Co., Ltd: Honoraria; CHUGAI PHARMACEUTICAL CO., LTD.: Honoraria.

A Unique Crosstalk between Tumor Cells and Hematopoietic Stem Cells Reveals a Myeloid Differentiation Pattern Signature Contributing to Metastasis

Metastasis is the major cause of death in cancer patients. Recent studies have demonstrated that the crosstalk between different host and tumor cells in the tumor microenvironment regulates tumor progression and metastasis. Specifically, immune cell myeloid skewing is a prominent promoter of metastasis. While previous studies have demonstrated that the recruitment of myeloid cells to tumors is a critical step in dictating tumor fate, the reservoir of these cells in the bone marrow (BM) compartment and their differentiation pattern has not been explored. Here we utilized a unique model system consisting of tumor cell clones with low and high metastatic potential (met-low and met-high, respectively) derived from melanoma and breast carcinoma cell lines. Hematopoietic stem cells (HSCs) and their early progenitor subset were defined as Lin-/Sca1+/CD117+, representing LSK cells. BM transplantation experiments using GFP-positive LSK cells derived from met-low and met-high tumor bearing mice were carried out to study lineage differentiation. The genetic signatures of LSK cells were analyzed by single cell RNA-sequencing (scRNA-seq). This analysis included unbiased automated annotation of individual cell types by correlating single-cell gene expression with reference transcriptomic data sets (SingleR algorithm) in order to evaluate the proportions of cell types in BM and reveal cell type-specific differentially expressed genes. Expression patterns of proteins originated from tumor cells were analyzed using a range of multi-omics techniques including nanostring, protein array, and mass spectrometry analysis. Tumor proteomic data was integrated with differential receptor expression patterns in BM cell types to reveal novel crosstalk between tumor cells and HSCs in the BM compartment. Mice bearing met-high tumors exhibited a significant increase in the percentage of LSK cells in the BM in comparison to tumor-free mice or mice bearing met-low tumors. These results were confirmed by functional CFU assays of peripheral blood of met-high compared to met-low tumor bearing mice. In addition, mice that underwent BM transplantation with GFP-positive LSK cells obtained from met-high inoculated donors exhibited an increased percentage of circulating GFP-positive myeloid cells in comparison to counterpart mice transplanted with LSK cells from met-low inoculated donors. Moreover, scRNA-seq analysis of LSK cells obtained from the BM of met-low and met-high tumor bearing mice revealed that met-high tumors induce the enrichment of monocyte-dendritic progenitor population (MDP), confirmed also by flow cytometry. To uncover the possible factors involved in myeloid programming of LSK cells, we performed a proteomic screen of tumor conditioned medium and integrated the results with the scRNA-seq data analysis. This analysis revealed that the IL-6-IL-6R axis is highly active in LSK-derived MDP cells from mice bearing met-high tumors. An adoptive transfer experiment using MDP-GFP+ cells obtained from BM of met-high tumor bearing mice demonstrated that met-high tumors directly dictate HSC fate decision towards myeloid bias, resulting in increased metastasis. Evidently, blocking IL-6 in mice bearing met-high tumors reduced the number of MDP cells, and consequently decreased metastasis. Our study reveals a unique crosstalk between tumor cells and HSCs. It provides new insight into the mechanism by which tumors contribute to the presence of supporting stroma. Specifically, tumors secreting IL-6 dictate a specific genetic signature in HSCs that programs them towards myeloid differentiation, thereby inducing a metastatic switch. Disclosures No relevant conflicts of interest to declare.

Voice of Cancer Patients: Patient Experience Regarding Use of Tyrosine Kinase Inhibitors in Chronic Myeloid Leukemia

Background: Use of Tyrosine Kinase inhibitors (TKIs) have significantly improved the prognosis of Chronic Myelogenous Leukemia (CML). Since the first clinical use of Imatinib 20 years ago, second generation TKIs have been approved for first line treatment, which include Dasatinib (approved in Nov. 2010), Nilotinib (June 2010) and Bosutinib (Dec. 2017). Ponatinib, a third generation TKI (approved for third line treatment in Dec. 2012), is the only effective TKI in patients with t315i mutation in bcr/abl gene. In this study, we analyzed patient experiences and use of various TKIs in CML patients. Method: Many patients share their experiences in online forums that contain clinically relevant information. However, data is unstructured and hence difficult to analyze. We collected 18.2 million messages from 97 different unrestricted cancer forums, including those 44 that were CML related. We created custom ontology for CML and TKIs regarding their efficacy and side effects. We then used our AI-based platform, VoCP, to analyze these messages by using artificial intelligence techniques, e.g., natural language processing, topic modeling and machine learning. Results: VoCP found 87,555 messages regarding CML from 10,605 unique users. Of these, 4,857 users shared 11,017 messages containing experiences with TKIs. 2,164 users mentioned the use of Imatinib, 819 used Dasatinib, 747 used Nilotinib, 97 used Bosutinib and 71 used Ponatinib. 47 patients mentioned undergoing bone marrow transplant. 1,139 patients mentioned being diagnosed before 2010 and at least 938 of them started with Imatinib. 1,082 patients reported diagnosis between 2010-2017; 357 started with Imatinib, 235 with Dasatinib and 236 with Nilotinib. 163 patients reported diagnosis after 2017; 47 started with Imatinib, 51 with Dasatinib, 27 with Nilotinib and 5 with Bosutinib. Imatinib: Switches: 501 patients switched to Dasatinib, 248 to Nilotinib, 14 to Bosutinib and 7 to Ponatinib. Side effects: 2,164 users mentioned 939 messages with side effects, which included pain 220 (23.4%), myelosuppression 154 (16.4%), fatigue 111 (11.7%), Skin rash (11.6%), GI upset 70 (2.4%), edema 84 (8.9%) heart problems 17, DVT/PE 5 and renal dysfunction 5. Dasatinib: Switches: 60 patients switched from Dasatinib to Imatinib, 79 to Nilotinib, 28 to Bosutinib and 9 to Ponatinib. Side effects: 819 patients shared 587 messages with side effects, which included Myelosuppression 113 (9.2%), rash 87 (14%), headache 78 (12.2%), pain 61 (1.7%), edema 30, Pleural effusion 24 and abdominal pain 11. Nilotinib: Switches: 95 patients switched to Dasatinib, 57 to Imantinib, 13 switched to Bosutinib and 5 to Ponatinib. Side effects: 747 users shared 390 messages with side effects, which included rash 135 (34.6%), pain 62 (15.9%), Myelosuppression 43 (11%), edema 16 (4.1%), cardiac issues 8 (2%), GI issues 13 (3.3%) and abdominal pain 2. Bosutinib: Switches: 1 patient switched from Bosutinib to Imatinib, 4 to Dasatinib, 2 to Nilotinib and 1 to Ponatinib. Side effects: 97 patients shared 39 messages with side effects, which included nausea 9 (23%), Myelosuppression 6(15%), edema 5 (12.8%) and diarrhea 4 (1.1%). Ponatinib: Switches: 3 patients mentioned switching from Ponatinib to Dasatinib, 3 patients to Bosutinib, 2 to Nilotinib, and 1 to Imatinib. Side effects: 71 users shared 25 messages with side effects, which included rash 13 (51%), pancreatitis 1 and fatigue 1. Conclusions: Despite the approval of second generation TKIs, Imatinib is most commonly used for treating CML in first line. MMR and CMR are similar for all TKIs. VoCP reliably provides meaningful insights from the patient's point of view and gives insight into unmet needs where more resources and research should be focused. Table Disclosures Aggarwal: Scry Analytics,Inc: Equity Ownership. Aggarwal:Scry Analytics, Inc.: Equity Ownership.

Sickle Cell Disease Burden in North Lebanon

Background: Sickle cell disease (SCD) is one of the most prevalent hemoglobinopathies in Lebanon, where 0.1% of the population are affected by the disease, with the highest prevalence in North Lebanon. SCD burden has not been well characterized in this patient population. Moreover, there is limited understanding of the factors associated with complications of SCD. We hereby report on characteristics, complications, treatments and survival of a SCD cohort treated at a comprehensive SCD referral clinic in North Lebanon. Methods: Data were extracted from the health records and electronic registry of 335 SCD patients treated at the comprehensive SCD clinic of Nini hospital, Tripoli, North Lebanon between 2009 and 2019. The study population consisted of referred and newly diagnosed patients. Patients were considered to be newly diagnosed with SCD if there was a gap of ≤ 60 days between SCD diagnosis date and their first clinic visit date. Patients were regularly seen in the clinic at intervals ranging from every 2 months to 1 year depending on their age and disease severity. Patient characteristics, complications, treatment choices, and mortality were evaluated during follow-up. Follow-up was defined as the time between SCD diagnosis and last visit to the clinic. Complications included vaso-occlusive crisis (VOC), acute splenic sequestration (ASS), stroke, dactylitis, joint necrosis, priapism, leg ulcers, sepsis, iron overload and mortality. VOC events, defined as the composite of pain and/or acute chest syndrome (ACS), were only reported if they resulted in a hospitalization. Since history of VOC events was not well documented among referred patients, VOC events were assessed among patients newly diagnosed at the clinic. Results: The mean age of the study population at SCD diagnosis was 2.9 years (standard deviation [SD]: 4.3), with 73.1% of patients diagnosed within 3 years of age. Mean age at first visit to the clinic was 8.6 years (SD 10.0). 159 (47.5%) patients were female. The most common genotypes were Hemoglobin SS (233 [69.6%]), Hemoglobin Beta-0 Thalassemia (62 [18.5%]), and Hemoglobin Beta + thalassemia (27 [8.1%]). The mean number of follow up years between SCD diagnosis date and latest visit date to the clinic was 13.7 (SD: 10.5). 132 (39.4%) patients were newly diagnosed at the time of their first visit to the clinic. The most frequently encountered SCD clinical events were pain (189 [56.4%]) followed by ACS (135 [40.3%]), ASS (115 [34.3%]) and joint necrosis (55 [16.4%]). The incidence of stroke, pulmonary hypertension, priapism, leg ulcers and sepsis was low (3.3%, 4.2%, 6.0%, 3.0% and 3.9%). Persistent splenomegaly beyond 6 years was seen in 57 (17%) patients, 36 (63.2%) of these patients were of SS genotype. 276 (82.4%) patients required at least one hospitalization during their follow-up. Among newly diagnosed patients, 63% experienced at least one VOC event that led to a hospitalization with a mean of 0.4 (SD: 0.6) hospitalized VOC events per patient per year. 15 (4.5%) patients died during follow-up. The most common cause of death was stroke (3 [20%]). 84 (25.1%) and 76 (22.7%) patients underwent a cholecystectomy and surgical splenectomy respectively, and 30 (9.0%) patients underwent both. 236 (70.5%) patients were treated with Hydroxyurea. The mean age at introduction of Hydroxyurea was 11.5 years (SD: 10.1) and median starting dose was 15.2 mgs/kg/day. 281 (84%) patients received at least one blood transfusion during their follow-up. 37 (11.0%) patients received iron chelation during their follow up. 3 (0.9%) patients underwent bone marrow transplant and were cured of their disease. Conclusion: This first SCD study from North Lebanon demonstrates that SCD burden in North Lebanon is significant. Despite the high disease burden and the low community resources in this region, survival rate of this SCD patient population is relatively high. This can be attributed to the young age at diagnosis, the close comprehensive follow-up and the regular parent/patient education. The low rate of stroke, priapism and leg ulcers in this population warrants further investigation via disease associated markers and genetic determinants. As for priapism, it may be underreported due to social stigma in a conservative country as Lebanon. Noteworthy, Iron overload is under recognized and sub optimally treated. The association between specific risk factors and disease complications will be further addressed. Disclosures Inati: Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novonordisk: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Research Funding; Global Blood Therapeutics: Research Funding. Kanakamedala:Novartis: Consultancy; Genesis Research: Employment. Pilipovic:Novartis Pharma AG: Employment, Equity Ownership. Sabah:Novartis: Employment.

Effects of Combination Hydroxyurea and Chronic Red Blood Cell Transfusion Therapy on the Immune Parameters of Patients with Sickle Cell Disease

Background: Sickle cell disease (SCD) is typically characterized as a red blood cell disorder but our understanding of the effects on the immune system is limited. Patients with sickle cell disease have been shown to have unique inflammatory profiles, immune phenotypes and function. Others have shown that during vaso-occlusive crises patients with SCD have elevated counts of neutrophils, monocytes, and cytokines as well as increased activity of invariant natural killer T cells (iNKT).We have previously shown that hydroxyurea use is associated with a normalization of the increased NK cell number and function. While there are studies that describe on the effects of single therapy, there is little known about combination therapy. Therefore, our study investigated immunological changes in pediatric patients on combination therapy, which was defined as hydroxyurea added to chronic red blood cell transfusion treatment. Methods: Patient data and peripheral blood samples were collected from an ongoing pilot study of combination therapy hydroxyurea and simple chronic transfusion in patients with SCD previously on chronic transfusion for stroke prevention. A total of 11 patients with hemoglobin SS were studied at two time points; baseline (on chronic RBC transfusion only) and 3 months follow up after initiation of hydroxyurea 20 mg/kg/day. Comparisons were performed using paired t-tests with a p-value &lt;0.05 being considered significant. Results: T, B and NK cell percentage was similar between baseline and after 3 months of combination therapy 62.5% (44.3-71.9) vs 67% (17.6-82.7), 16.29%(8.15-30.2) vs. 13.26% (1.07-32.8) and 7.79% (4.16-14.7) vs. 6.88 (1.54-21) (p&gt;0.05). There were no significant differences between markers of NK cell activation between baseline and 3 months as follows: NKG2D 4.89% (0.47-28.4) vs. 24.38% (0.88-63), and NKp30 8.40% (0.81-58.7) vs. 32.42% (0.45-86.9). However there was a significant decrease in the percentage of mature (CD57+) NK cells 33.8% (10.7-67.6) vs. 23.07%(4.23-37), p =0.005. Similar results were also seen when using absolute values of the different lymphocyte subsets. Conclusion: Combination therapy appears to not affect overall percentages of B, T and NK cells but does appear to decrease the percentage of mature CD57+ NK cells that are known to have increased cytolytic activity. We plan to investigate the implications of these findings using NK functional studies such as cytotoxicity assays and cytotoxic granule release to further elucidate if combination therapy can lead to a decrease in NK cell function to normal levels. Additionally we plan to assess the effect on the immune parameters at 1 year as the hydroxyurea effect is likely time-dependent. These findings may have implications for patients on chronic transfusion therapy who plan to undergo bone marrow transplantation where a reduction in the potential for graft rejection by NK cells is desired. Disclosures No relevant conflicts of interest to declare.

Transformed bone marrow cells generate neoplasms of distinct histogenesis. a murine model of cancer transplantation.

The last several years have witnessed renewed interest regarding the contribution of cancer stem cells in tumorigenesis and neoplastic heterogeneity. It has been reported that patients who undergo bone marrow transplantation are more prone to develop a malignancy during their life time; usually hematological tumors, but solid neoplasms may also develop, which in certain instances are donor-derived. It has also been well documented that multipotent bone marrow derived cells can migrate to diverse organs, differentiating into various histological lineages. The present study reports an experimental syngeneic transplantation model, using fluorescently tagged bone marrow cells from p53 null male mice into female wild-type counterparts. We found that transplanted non-neoplastic mutant bone marrow cells can generate tumors of distinct histogenesis, including thymic lymphomas, sarcomas, and carcinomas after carcinogen induction, providing evidence that multipotent cancer-prone stem cells can reside in the bone marrow and are transplantable.

“Can you tell me why you made that choice?”: A qualitative study of the influences on treatment decisions in advance care planning among adolescents and young adults undergoing bone marrow transplant

Background: Adolescent and young adult advance care planning is beneficial in improving communication between patients, surrogates, and clinicians. The influences on treatment decisions among adolescents and young adults are underexplored in the literature. Aim: The aim of this study was to explore and better understand the influences on decision-making for adolescent and young adult bone marrow transplant patients about future medical care. Design: Clinical case studies and qualitative inductive content analysis of treatment decisions made during the Respecting Choices® Next Steps Pediatric Advance Care Planning conversation as a component of the Family-Centered Advance Care Planning Intervention. Settings/participants: A total of 10 adolescent and young adult patients (aged 14–27 years) undergoing bone marrow transplant at an academic Midwest children’s hospital were involved in the study. Results: Influences on participants’ decisions were consideration for family, quality of life, and awareness of self. Desire to avoid suffering and maintain an acceptable quality of life was often in competition with participant’s concern over the perceived negative impact of discontinuing treatment on their families. Conclusion: This study highlights that adolescent and young adult bone marrow transplant patients are capable of meaningful deliberation about future treatment decisions. Influences on decision-making should be incorporated into advance care planning conversations to facilitate communication between patients and their surrogates. Longitudinal research is needed to explore these influences throughout the trajectory of illness.

1778. Epstein–Barr Virus Genetic Diversity: Evaluation of BZLF1 Variants among Bone Marrow Transplant Patients and Individuals with Infectious Mononucleosis

BackgroundEpstein–Barr virus (EBV) is associated with several diseases, including infectious mononucleosis (IM) and malignant disorders, including post-transplant lymphoproliferative disorder (PTLD). The relationship between strains of the virus and disease manifestations or illness severity is of interest. Such strains have been defined by genetic variations in the major viral genes. Data involving the patterns of genetic diversity of the virus in different populations are required. We examined the genetic diversity of the BZLF1 gene, which is a major lytic gene of the virus.MethodsWe sequenced the BZLF1 gene of EBV following amplification from DNA that was extracted from blood obtained from pediatric bone marrow transplant (BMT) patients and children and young adults with IM. Sequencing was done by Sanger methodology (dideoxy DNA sequencing) and the sequences were aligned with a reference strain of EBV using Geneious software. The variant burden and types of single nucleotide variants (SNV) were compared across the 3 exons of the BZLF1 gene.ResultsWe sequenced the BZLF1 gene using 21 patients with IM (median age 14, age range 2–19 years) and 11 who underwent bone marrow transplantation (median age 6, range 3–13 years). Three of 11 BMT patients developed post-transplant lymphoproliferative disorder (PTLD). Among the 3 exons, exon 1 had the greatest diversity across both study groups. There was a tendency for less diversity among PTLD samples, with no sample containing >1 single nucleotide variant (SNV) in contrast to the other samples. In samples that contained SNVs, there was a non-statistically significant trend for more SNVs to occur among the IM samples compared with PTLD samples (median 4.5 and 0, respectively; P > 0.05). Additionally, 2/11 (18.2%) BMT sequences contained more than 1 SNV compared with 7/21 (33.3%) IM sequences (P > 0.05).ConclusionThere was a tendency for more genetic diversity among samples from patients with IM compared with bone marrow transplant patients, notably those with PTLD. Further studies will determine if this tendency is due to selective pressures in the transplant setting, including but not limited to the use of antiviral agents directed at the lytic phase of EBV.Disclosures All authors: No reported disclosures.

Parenteral Nutrition Complications in Children Undergoing Bone Marrow Transplantation.

Parenteral nutrition (PN) seems to be a practical solution to face the negative nutritional effects of bone marrow transplantation. Report and describe all observed PN-related complications in children undergoing allogenic bone marrow transplantation in a tertiary center and determine the possible risk factors. This was a retrospective and observational study including 51 allografted children 2 to 17 years of age. We collected from medical patient records any noticed PN-related complications using an assessment causality method. The independent risk factors for complications were investigated by multivariate analysis. A total of 92% of patients (n=47) developed a total of 136 complications attributable to PN. The incidence rate of complications was 5 for 100 patient days of PN. Infectious complications (32.3%) and electrolytic disorders (27.9%) were the most common conditions identified during our study. Multivariate analysis showed that the duration of PN exposure, age, and hyperglycemia were the risk factors for the onset of these complications. Although we have noticed multiple complications attributable to PN, a certain causal link is difficult to establish in this particular context. Emphasizing enteral nutrition in bone marrow graft protocols would be the best way to avoid these complications.

P6346Purinergic receptor Y6 (P2Y6) deficiency impairs left ventricular function

Abstract Introduction Cardiomyopathies due to pathological remodelling are the most common myocardial disorders and leading indication for heart transplant in young adults. Cardiomyocytes rely on sessile macrophage phagocytosis for cell homeostasis. Purinergic receptor Y6, selectively binding to UDP, promotes phagocytosis and is involved in several tissue-remodelling processes. We hypothesize a critical role of P2Y6 in the maintenance of cardiac tissue homeostasis in vivo. Methods Echocardiography was performed on male C57Bl6 wild-type (WT) and P2Y6-deficient (KO) mice at different ages up to 20 weeks. In addition, WT and KO mice underwent bone marrow transplantation. For histological analysis, hearts from WT and KO mice were stained with HE, Masson's trichrome, wheat germ agglutinin, CD11b, LC3B and TUNEL. Cardiac ultrastructure of WT and KO hearts was investigated by electron microscopic imaging. Furthermore, uptake of fluorescent pHrodo bioparticles by WT and KO bone marrow derived macrophages (BMDMs), either in presence or absence of specific P2Y6 agonist UDP or full antagonist MRS2578, was measured in vitro. Results KO mice were significantly impaired in their LV function by reduced ejection fraction (WT: 57.37±1.27%, n=13, KO: 44.13±1.09%, n=16, p&lt;0.0001), stroke volume (WT+: 39.25±1.94μl, n=13, KO: 33.57±1.94μL, n=16, p&lt;0.05), and cardiac output (WT: 20.79±1.11 mL/min, n=13, KO: 17.84±0.85 mL/min, n=16, p&lt;0.05). A long-term follow-up revealed progressive impairment of the cardiac function (4 w: WT: 62.07±1.11%, n=5, KO: 48.73±1.03%, n=10, p&lt;0.0001; 6 w: WT: 54.29±1.88%, n=5, KO: 44.61±1.4%, n=10, p&lt;0.01; 8 w: WT: 56.43±1.44%, n=5, KO: 44.72±0.89%, n=10, p&lt;0.0001). Echocardiography 6 weeks after bone marrow transplantation demonstrated convalescence upon reconstitution with WT bone marrow (WT in KO: 46.19±2.68%, n=3 vs KO in WT: 38.40±1.26%, n=3). No major differences with regard to morphology, cell size, collagen deposition, leukocyte infiltration or apoptosis were observed in histology. However, LC3B expression was increased in KO mice (mean fluorescent area: WT: 191.1±19.93μm2, n=5, KO: 261.2±18.34μm2, n=10, p&lt;0.05). Electron microscopic imaging revealed a distinctly impaired ultrastructure with T-tubule remodelling, mitochondrial derangement and abnormal numbers of autophagosomes in KO hearts. In vitro, fluorescent particle phagocytosis by BMDMs was completely blocked after treatment with MRS2578. Conclusion Global P2Y6 deficiency leads to a progressive cardiomyopathy in mice, mainly characterized by an impaired left ventricular function and ultrastructural irregularities. Its exacerbation seems to be prevented by reconstitution with WT bone marrow. For the underlying mechanism, we conclude a deranged cardiomyocyte homeostasis in KO animals due to defective phagocytic activity of resident macrophages. Potential induction of cardiac clearance via P2Y6 signalling could be a promising therapeutic target in the field of cardiomyopathies.

PP-34 - Association of human leukocyte antigen groups with oral mucositis in patients undergoing bone marrow transplantation

PP-34 - Association of human leukocyte antigen groups with oral mucositis in patients undergoing bone marrow transplantation