Advances in Bone Marrow Evaluation.

Evaluation of bone marrow aspirate smear and trephine biopsy specimens is critical to the diagnosis of benign and malignant hematologic conditions. Digital pathology has the potential to revolutionize bone marrow assessment through implementation of artificial intelligence for assisted and automated evaluation, but there remain many barriers toward this implementation. This article reviews the current state of digital evaluation of bone marrow aspirate smears and trephine biopsies, recent research using machine learning models for automated specimen analysis, an outline of the advantages and barriers facing clinical implementation of artificial intelligence, and a potential vision of artificial intelligence-associated bone marrow evaluation.

High ferritin is associated with liver and bone marrow iron accumulation: Effects of 1-year deferoxamine treatment in hemodialysis-associated iron overload.

BACKGROUND: Iron (Fe) supplementation is a critical component of anemia therapy for patients with chronic kidney disease (CKD). However, serum Fe, ferritin, and transferrin saturation, used to guide Fe replacement, are far from optimal, as they can be influenced by malnutrition and inflammation. Currently, there is a trend of increasing Fe supplementation to target high ferritin levels, although the long-term risk has been overlooked. METHODS: We prospectively enrolled 28 patients with CKD on hemodialysis with high serum ferritin (> 1000 ng/ml) and tested the effects of 1-year deferoxamine treatment, accompanied by withdrawal of Fe administration, on laboratory parameters (Fe status, inflammatory and CKD-MBD markers), heart, liver, and iliac crest Fe deposition (quantitative magnetic resonance imaging [MRI]), and bone biopsy (histomorphometry and counting of the number of Fe positive cells in the bone marrow). RESULTS: MRI parameters showed that none of the patients had heart iron overload, but they all presented iron overload in the liver and bone marrow, which was confirmed by bone histology. After therapy, ferritin levels decreased, although neither hemoglobin levels nor erythropoietin dose was changed. A significant decrease in hepcidin and FGF-23 levels was observed. Fe accumulation was improved in the liver and bone marrow, reaching normal values only in the bone marrow. No significant changes in turnover, mineralization or volume were observed. CONCLUSIONS: Our data suggest that treatment with deferoxamine was safe and could improve Fe accumulation, as measured by MRI and histomorphometry. Whether MRI is considered a standard tool for investigating bone marrow Fe accumulation requires further investigation. Registry and the registration number of clinical trial: ReBEC (Registro Brasileiro de Ensaios Clinicos) under the identification RBR-3rnskcj available at: https://ensaiosclinicos.gov.br/pesquisador.

Study of long-term effects of pelvic radiotherapy on the function of bone marrow in recurrent cervical cancer patients.

Purpose: To study the effects of prior pelvic radiotherapy on bone marrow suppression in recurrent cervical cancer patients during chemotherapy. Methods and materials: The cases of 129 patients with recurrent cervical cancer were reviewed, of which 77 patients had pelvic radiotherapy history and another 52 patients with no pelvic radiotherapy history were used as control group. All patients received a chemotherapy regimen of paclitaxel combined with carboplatin (TC) per 21 days for 5-6 times. Hematologic toxicity, including count of red blood cell, white blood cell and neutrophil cell and platelet, was defined by using Common Terminology Criteria for Adverse Events (version 4.0). The relationship between age, body mass index, disease free survival, pathological types, FIGO stages, radiotherapy methods and the degree of bone marrow suppression during chemotherapy was statistically analyzed, respectively, for all recurrent cervical cancer patients. Results: Among 77 patients with previous radiotherapy history, 73 recurrent patients (94.8%) had bone marrow suppression followed by chemotherapy. Recurrent cervical cancer patients without prior radiotherapy (n=52) showed a lower risk of bone marrow suppression followed by chemotherapy (n=39, 75.0%, P < 0.05). The probability of severe bone marrow suppression (grade III-IV) after chemotherapy in recurrent cervical patients with or without history of radiotherapy was 41.6% and 13.5%, respectively (P < 0.05). In univariate analysis, radiotherapy methods were associated with the incidence of grade III-IV bone marrow suppression in recurrent cervical cancer patients (P=0.005). In multivariate analysis, radiotherapy methods and extended-field radiotherapy were the risk factor of grade III-IV bone marrow suppression (χ2=16.975, P=0.001). No significant differences in the counts of white blood cell, hemoglobin and platelet were observed before chemotherapy at relapse between patients with and without prior radiotherapy. Reduction of white blood cell counts, absolute value of neutrophil cell and platelet counts composited majority type of grade III and IV bone marrow suppression. Conclusions: The prior pelvic radiotherapy significantly increased the incidence of bone marrow suppression during chemotherapy in recurrent cervical cancer patients. When treating recurrent cervical cancer patients with chemotherapy who had prior radiotherapy, especially for those experienced external beam radiation therapy, essential attention and timely intervention are recommended to ensure completion of chemotherapy and clinical efficacy.

[Chinese expert consensus on minimal residual disease detection in multiple myeloma based on bone marrow samples (2024)].

Multiple myeloma (MM) is the second most common hematologic malignant tumor. Standard holistic treatment model and new drug-based regimens have greatly improved the survival of patients with MM; however, minimal residual disease (MRD) causes relapse in most patients. Therefore, combining MRD testing on the basis of traditional serological efficacy evaluation is necessary to achieve a more accurate assessment of the patient's disease status. At present, next-generation flow cytometry (NGF) and next-generation sequencing (NGS) are the mainstream technologies for detecting MRD based on bone marrow samples. To standardize and normalize MRD detection, the expert group discussed and formulated Chinese expert consensus on the application of NGF and NGS technology for bone marrow MRD detection in patients with MM.

[Homing and characteristic analysis of macrophage in immune-mediated aplastic anemia model mice].

To investigate the dynamic homing process and characteristics of macrophages in different organs of immune-mediated aplastic anemia (AA) model mice. Macrophages in donor lymph nodes were sorted by magnetic beads and labeled with PKH67. After modeling according to the preparation method of the AA model, peripheral blood rountine analysis, bone marrow biopsy and HE staining results were analyzed to verify the modeling effect. On days 4, 8, and 12 of modeling, the bone marrow, spleen, and lymph node mononuclear cells were collected, and dynamic changes of PKH67-labeled macrophages in donor mice were analyzed by flow cytometry. In this study, dynamic changes in PKH67-labeled macrophages in the pathogenesis of AA model mice were explored. Macrophages in donor mice homed to the lymph nodes, expanding and differentiating in the lymph nodes, and finally transported to the bone marrow and spleen. Through proteomics mass spectrometry analysis, the related immune inflammatory response pathway of macrophages involved in the activation of the AA bone marrow microenvironment was preliminarily revealed, which provides a basis for the pathological macrophages involved in the pathogenesis of AA model mice.

Exploring the bone marrow micro environment in thalassemia patients: potential therapeutic alternatives.

Genetic mutations in the ß-globin gene lead to a decrease or removal of the ß-globin chain, causing the build-up of unstable alpha-hemoglobin. This condition is referred to as beta-thalassemia (BT). The present treatment strategies primarily target the correction of defective erythropoiesis, with a particular emphasis on gene therapy and hematopoietic stem cell transplantation. However, the presence of inefficient erythropoiesis in BT bone marrow (BM) is likely to disturb the previously functioning BM microenvironment. This includes accumulation of various macromolecules, damage to hematopoietic function, destruction of bone cell production and damage to osteoblast(OBs), and so on. In addition, the changes of BT BM microenvironment may have a certain correlation with the occurrence of hematological malignancies. Correction of the microenvironment can be achieved through treatments such as iron chelation, antioxidants, hypoglycemia, and biologics. Hence, This review describes damage in the BT BM microenvironment and some potential remedies.

C-Mannosyl tryptophan is a novel biomarker for thrombocytosis of myeloproliferative neoplasms.

C-Mannosyl tryptophan (CMW), a unique glycosylated amino acid, is considered to be produced by degradation of C-mannosylated proteins in living organism. Although protein C-mannosylation is involved in the folding and secretion of substrate proteins, the pathophysiological function in the hematological system is still unclear. This study aimed to assess CMW in the human hematological disorders. The serum CMW levels of 94 healthy Japanese workers were quantified using hydrophilic interaction liquid chromatography. Platelet count was positively correlated with serum CMW levels. The clinical significance of CMW in thrombocytosis of myeloproliferative neoplasms (T-MPN) including essential thrombocythemia (ET) were investigated. The serum CMW levels of the 34 patients with T-MPN who presented with thrombocytosis were significantly higher than those of the 52 patients with control who had other hematological disorders. In patients with T-MPN, serum CMW levels were inversely correlated with anemia, which was related to myelofibrosis (MF). Bone marrow biopsy samples were obtained from 18 patients with ET, and serum CMW levels were simultaneously measured. Twelve patients with bone marrow fibrosis had significantly higher CMW levels than 6 patients without bone marrow fibrosis. Collectively, these results suggested that CMW could be a novel biomarker to predict MF progression in T-MPN.

The crosstalk between lung cancer and the bone marrow niche fuels emergency myelopoiesis.

Modest response rates to immunotherapy observed in advanced lung cancer patients underscore the need to identify reliable biomarkers and targets, enhancing both treatment decision-making and efficacy. Factors such as PD-L1 expression, tumor mutation burden, and a 'hot' tumor microenvironment with heightened effector T cell infiltration have consistently been associated with positive responses. In contrast, the predictive role of the abundantly present tumor-infiltrating myeloid cell (TIMs) fraction remains somewhat uncertain, partly explained by their towering variety in terms of ontogeny, phenotype, location, and function. Nevertheless, numerous preclinical and clinical studies established a clear link between lung cancer progression and alterations in intra- and extramedullary hematopoiesis, leading to emergency myelopoiesis at the expense of megakaryocyte/erythroid and lymphoid differentiation. These observations affirm that a continuous crosstalk between solid cancers such as lung cancer and the bone marrow niche (BMN) must take place. However, the BMN, encompassing hematopoietic stem and progenitor cells, differentiated immune and stromal cells, remains inadequately explored in solid cancer patients. Subsequently, no clear consensus has been reached on the exact breadth of tumor installed hematopoiesis perturbing cues nor their predictive power for immunotherapy. As the current era of single-cell omics is reshaping our understanding of the hematopoietic process and the subcluster landscape of lung TIMs, we aim to present an updated overview of the hierarchical differentiation process of TIMs within the BMN of solid cancer bearing subjects. Our comprehensive overview underscores that lung cancer should be regarded as a systemic disease in which the cues governing the lung tumor-BMN crosstalk might bolster the definition of new biomarkers and druggable targets, potentially mitigating the high attrition rate of leading immunotherapies for NSCLC.

Tuberculosis of the bone marrow with secondary hemophagocytic lympho-histiocytosis presenting as obstructive jaundice: A clinician's challenge for the ages.

Tuberculosis. a disease of great public concern, is spread through inhalation of micro-droplets from an infected person. Despite lungs being the primary site, there may be multisystemic involvement, very rarely involving bone marrow, a dreaded manifestation of disseminated tuberculosis, associated with high mortality and morbidity. We report a case of tuberculosis of bone marrow with concomitant secondary hemophagocytic lympho-histiocytosis, bringing into light the importance of clinical suspicion and evaluation of bone marrow being a primary site of involvement in patients of disseminated tuberculosis.

CT guided versus non-image guided bone marrow aspiration and biopsy: Comparison of indications, specimen quality and cost.

PURPOSE: To compare the indications, specimen quality, and cost of CT versus non-image guided bone marrow aspirate and biopsy (BMAB). METHODS: All CT and non-image guided BMAB performed from January 2013-July 2022 were studied. Body-mass-index (BMI), skin-to-bone distance, aspirate, and core specimen quality, and core sample length were documented. Indications for CT guided BMAB were recorded. Categorical variables were compared using chi-squared test and continuous variables using Mann-Whitney test. Analysis of per-biopsy factors used linear mixed-effect models to adjust for clustering. Cost of CT and non-image guided BMAB was taken from patient billing data. RESULTS: There were 301 CT and 6535 non-image guided BMABs studied. All CT guided BMAB were studied. A subset of 317 non-image guided BMAB was selected randomly from the top ten CT BMAB referrers. BMI (kg/m2) and skin-to-bone distance (cm) was higher in the CT versus the non-image guided group; 34.4 v 26.8, p < 0.0001; 4.8 v 2.5, p < 0.0001, respectively. Aspirate and core sample quality were not different between groups, p = 0.21 and p = 0.12, respectively. CT guided core marrow samples were longer, p < 0.0001. The most common CT BMAB referral indications were large body habitus (47.7 %), failed attempt (18.8 %) and not stated (17.4 %). Cost of a CT guided BMAB with conscious sedation was $3945 USD versus $310 USD for non-image guided. CONCLUSION: CT guided BMAB are commonly performed in patients with large body habitus and failed attempt. However, the cost is 12.7 fold higher with no increase in specimen quality. These findings can help referrers be cost conscious.

DCE-MRI to distinguish all monoclonal plasma cell disease stages and correlation with diffusion-weighted MRI/PET-based biomarkers in a hybrid simultaneous whole body-2-[18F]FDG-PET/MRI imaging approach.

BACKGROUND: Dynamic contrast-enhanced-MRI (DCE-MRI) is able to study bone marrow angiogenesis in patients with multiple myeloma (MM) and asymptomatic precursor diseases but its role in the management of MM has not yet been established. The aims of this prospective study was to compare DCE-MRI-based parameters between all monoclonal plasma cell disease stages in order to find out discriminatory parameters and to seek correlations with other diffusion-weighted MRI and positron emission tomography (PET)-based biomarkers in a hybrid simultaneous whole-body-2-[18F]fluorodeoxyglucose (FDG)-PET/MRI (WB-2-[18F]FDG-PET/MRI) imaging approach. METHODS: Patients with newly diagnosed Monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM) or symptomatic MM according to international myeloma working group and underwent WB-2-[18F]FDG-PET/MRI imaging including bone marrow DCE sequences at the Nantes University Hospital were prospectively enrolled in this study before receiving treatment. RESULTS: One hundred and sixty-seven patients (N = 167, mean age: 64 years ± 11 [Standard deviation], 66 males) were considered for the analysis. DCE-MRI-based Peak Enhancement Intensity (PEI), Time to PEI (TPEI) and their maximum intensity time ratio (MITR: PEI/TPEI) values were significantly different between the different monoclonal plasma cell disease stages, PEI values increasing and TPEI values decreasing progressively along the spectrum of plasma cell disorders, from MGUS stage to symptomatic multiple myeloma. PEI values were significantly higher in patients with diffuse bone marrow involvement (either in PET or in MRI images) than in those without diffuse bone marrow involvement, unlike TPEI values. PEI and TPEI values were not significantly different between patients with or without focal bone lesions. CONCLUSION: Different DCE-MRI-based parameters (PEI, TPEI, MITR) could significantly differentiate all monoclonal plasma cell disease stages and complemented conventional MRI and PET-based biomarkers.

Flow cytometry in the differential diagnosis of myelodysplastic neoplasm with low blasts and cytopenia of other causes.

Background: Myelodysplastic neoplasms (MDS) are characterized by cytopenia, morphologic dysplasia, and genetic abnormalities. Multiparameter flow cytometry (FCM) is recommended in the diagnostic work-up of suspected MDS, but alone is not sufficient to establish the diagnosis. Our aim was to investigate the diagnostic power of FCM in a heterogeneous population of patients with cytopenia, excluding cases with increased blast count. Methods: We analyzed bone marrow samples from 179 patients with cytopenia (58 MDS, 121 non-MDS) using a standardized 8-color FCM method. We evaluated the sensitivity, specificity, and accuracy of several simple diagnostic approaches, including Ogata score, extended Ogata score, the WHO and ELN iMDSFlow recommended "3 aberrations in two cell compartments method," and the combination of the Ogata score and "3 aberrations in two cell compartments method." The patients were followed until the diagnosis was confirmed, with a median follow-up of 2 months (range 0.2-27). Results: The combination of Ogata score and "3 aberrations in two cell compartments method" achieved the highest diagnostic accuracy (78%) with sensitivity and specificity 61% and 86%, respectively. When using only the "3 aberrations in two cell compartments method," the accuracy was 77% with a sensitivity of 72% and a specificity of 79%. The most frequently observed etiologies among the false positive cases were substrate deficiencies, inflammation/infection, or toxic effects. MDS can be excluded in all these cases after a thorough clinical evaluation and a relatively short follow-up. Conclusion: FCM remains an important but supplementary part in an integrated diagnostic process of MDS with low blasts. The combination of the Ogata score and the "3 aberrations in two cell compartments method" slightly improves accuracy compared to the detection of "3 aberrations in two cell compartments method" alone.

Immune infiltration-related genes regulate the progression of AML by invading the bone marrow microenvironment.

In this study, we try to find the pathogenic role of immune-related genes in the bone marrow microenvironment of AML. Through WGCNA, seven modules were obtained, among which the turquoise module containing 1793 genes was highly correlated with the immune infiltration score. By unsupervised clustering, the turquoise module was divided into two clusters: the intersection of clinically significant genes in the TCGA and DEGs to obtain 178 genes for mutation analysis, followed by obtaining 17 genes with high mutation frequency. Subsequently, these 17 genes were subjected to LASSO regression analysis to construct a riskscore model of 8 hub genes. The TIMER database, ImmuCellAI portal website, and ssGSEA elucidate that the hub genes and risk scores are closely related to immune cell infiltration into the bone marrow microenvironment. In addition, we also validated the relative expression levels of hub genes using the TCGA database and GSE114868, and additional expression levels of hub genes in AML cell lines in vitro. Therefore, we constructed an immune infiltration-related gene model that identify 8 hub genes with good risk stratification and predictive prognosis for AML.

Value and limitations of targeted next-generation sequencing in idiopathic hypereosinophilia: an integrative diagnostic tool in challenging cases.

Here, we reviewed clinical-morphological data and investigated mutational profiles by NGS in a single-center series of 28 consecutive patients admitted to our hospital between September 2011 and November 2021 for idiopathic hypereosinophilia (HE).Bone marrow (BM) morphology was evaluated in 22 patients: while in six subjects BM was unremarkable, in the remaining cases an increase in BM eosinophils was observed, together with a slight increase in BM fibrosis (MF-1) in 5/22 patients.A total of 4/28 patients had at least one genetic lesion by targeted NGS. In particular, the genes involved were: two each of TET2 and DNMT3A; and one each of JAK2V617F, ASXL1, PPM1D, and ZBTB33. Notably, JAK2V617F and TET2 mutations co-occurred, with the JAK2V617F-mutated sample also carrying TET2 lesions. Median VAF was 21%, with the exception of the oncodriver JAK2V617F, which showed a VAF > 50% in the reported case. Of note, of the four cases bearing lesions, 2/4 had multiple hits in different genes.While in recent years mutational analysis using NGS has proven to be able to differentiate clonal hematopoietic neoplasms from reactive processes in diagnostically difficult cases, we found somatic mutations in only 14.3% of patients who acceded to our hospital for idiopathic HE. More importantly, excluding the JAK2V617F-mutated case with an underlying MPN-Eo diagnosis, NGS was able to identify somatic mutations in only three cases, all older than 70 years. Consequently, the detection of these mutations in idiopathic HE patients should be interpreted with caution and only in the context of other supportive clinical-pathological findings.

Multi-omics differences in the bone marrow between essential thrombocythemia and prefibrotic primary myelofibrosis.

Essential thrombocythemia (ET) and prefibrotic primary myelofibrosis (pre-PMF) are Philadelphia chromosome-negative myeloproliferative neoplasms. These conditions share overlapping clinical presentations; however, their prognoses differ significantly. Current morphological diagnostic methods lack reliability in subtype differentiation, underlining the need for improved diagnostics. The aim of this study was to investigate the multi-omics alterations in bone marrow biopsies of patients with ET and pre-PMF to improve our understanding of the nuanced diagnostic characteristics of both diseases. We performed proteomic analysis with 4D direct data-independent acquisition and microbiome analysis with 2bRAD-M sequencing technology to identify differential protein and microbe levels between untreated patients with ET and pre-PMF. Laboratory and multi-omics differences were observed between ET and pre-PMF, encompassing diverse pathways, such as lipid metabolism and immune response. The pre-PMF group showed an increased neutrophil-to-lymphocyte ratio and decreased high-density lipoprotein and cholesterol levels. Protein analysis revealed significantly higher CXCR2, CXCR4, and MX1 levels in pre-PMF, while APOC3, APOA4, FABP4, C5, and CFB levels were elevated in ET, with diagnostic accuracy indicated by AUC values ranging from 0.786 to 0.881. Microbiome assessment identified increased levels of Mycobacterium, Xanthobacter, and L1I39 in pre-PMF, whereas Sphingomonas, Brevibacillus, and Pseudomonas_E were significantly decreased, with AUCs for these genera ranging from 0.833 to 0.929. Our study provides preliminary insights into the proteomic and microbiome variations in the bone marrow of patients with ET and pre-PMF, identifying specific proteins and bacterial genera that warrant further investigation as potential diagnostic indicators. These observations contribute to our evolving understanding of the multi-omics variations and possible mechanisms underlying ET and pre-PMF.

Insights into ionizing radiation-induced bone marrow hematopoietic stem cell injury.

With the widespread application of nuclear technology across various fields, ionizing radiation-induced injuries are becoming increasingly common. The bone marrow (BM) hematopoietic tissue is a primary target organ of radiation injury. Recent researches have confirmed that ionizing radiation-induced hematopoietic dysfunction mainly results from BM hematopoietic stem cells (HSCs) injury. Additionally, disrupting and reshaping BM microenvironment is a critical factor impacting both the injury and regeneration of HSCs post radiation. However, the regulatory mechanisms of ionizing radiation injury to BM HSCs and their microenvironment remain poorly understood, and prevention and treatment of radiation injury remain the focus and difficulty in radiation medicine research. In this review, we aim to summarize the effects and mechanisms of ionizing radiation-induced injury to BM HSCs and microenvironment, thereby enhancing our understanding of ionizing radiation-induced hematopoietic injury and providing insights for its prevention and treatment in the future.

[Correlation analysis of polyclonal plasma cell proportion in the bone marrow with clinical characteristics of patients with newly diagnosed multiple myeloma].

Objective: To explore the correlation of bone marrow polychonal plasma cell proportion (pPC% ) and clinical features in newly diagnosed multiple myeloma (NDMM) patients. Methods: A retrospective analysis of 317 patients with NDMM admitted to Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2018 to January 2023 was performed. The results of the pPC% in all patients were clear. The relationship between the pPC% and clinical characteristics was analyzed. Results: A total of 317 patients were included, comprising 180 males and 137 females. The median age at diagnosis was 61 (26-91) years, and 55.8% were 60 years or older. The pPC% in the bone marrow of patients with NDMM was different in the DS, International Staging System (ISS), and revised ISS (R-ISS) stages (P=0.002, 0.010, and 0.049, respectively), whereas no statistical difference in pPC% was observed among patients with different FISH risk stratigrams (P=0.971). The correlation coefficient between pPC% and hemoglobin (HGB) at the first diagnosis in patients was 0.211 (P<0.01). The correlation coefficients with serum calcium, serum creatinine, M protein level, and ß(2)-microglobulin were -0.141, -0.120, -0.181, and -0.207, respectively, and the results of the significance test were P=0.012, 0.033, 0.004, and 0.002, respectively, indicating a negative correlation. Compared with the patients with a pPC% of ≥2.5%, the group of patients with a pPC% of <2.5% had significantly higher levels of light chain, serum calcium, serum creatinine, M protein, and ß(2)-microglobulin at the initial diagnosis (P<0.05) ; lower HGB level (P<0.001) ; and a higher proportion of patients in ISS stage Ⅲ (P=0.034) . Conclusion: In this study, the pPC% in patients with NDMM was associated with clinical features of good prognosis, including higher HGB, lower serum calcium, serum creatinine, M protein quantity, ß(2)-microglobulin, light chain involvement, lower proportion of advanced disease (DS stage and ISS stage Ⅲ), and clinical features showing lower tumor burden.

[Introduction of a decalcification method for bone marrow biopsy tissue].

Bone marrow biopsy is one of the important means of hematopathological diagnosis, which has decisive diagnostic significance for various benign and malignant lymphohematopoietic system diseases. Its diagnostic value includes morphological observation, immunohistochemistry, genetics, and molecular biology testing. Owing to the unique nature of bone marrow biopsy, decalcification is an essential step in the pre-treatment process. Its purpose is to remove calcium from bone tissue, preserve intact collagen fiber components, facilitate tissue sectioning, and prevent tissue detachment during staining. If bone marrow biopsy lacks sufficient decalcification, preparing a section is difficult. Conversely, if decalcification is excessive, it can seriously disrupt tissue antigen activity. Therefore, a decalcification method with high decalcification efficiency and mild antigen damage is essential for bone marrow biopsy. This article introduces a bone marrow biopsy tissue decalcification method with high efficiency and less antigen loss: decalcification is performed at room temperature with 12% formic acid and 8% hydrochloric acid decalcification solution on a shaker.