METHODS OF MULTICLASSICATION OF BONE MARROW CELLS FOR THE DIAGNOSIS OF ACUTE LEUKEMIA AND MINIMAL RESIDUAL DISEASE (ON THE MATERIALS OF THE LABORATORY OF HEMATOPOIESIS OF N. N. BLOKHIN NATIONAL MEDICAL RESEARCH CENTER OF ONCOLOGY)

Author(s):  
Валентина Викторовна Дмитриева ◽  
Николай Николаевич Тупицын ◽  
Евгений Валерьевич Поляков ◽  
Софья Сергеевна Денисюк

Применение методов и средств цифровой обработки изображений при распознавании типов клеток крови и костного мозга для повышения качества диагностики острых лейкозов является актуальной научно-технической задачей, отвечающей стратегии развития технологий искусственного интеллекта в медицине. В работе предложен подход к мультиклассификации клеток костного мозга при диагностике острых лейкозов и минимальной остаточной болезни. Для проведения экспериментальных исследований сформирована выборка из 3284 изображений клеток, представленных Лабораторией гемопоэза Национального медицинского исследовательского центра онкологии им. Н.Н. Блохина. Предложенный подход к мультиклассификации клеток костного мозга основан на бинарной модели классификации для каждого из исследуемых классов относительно остальных. В рассматриваемой работе бинарная классификация выполняется методом опорных векторов. Метод мультиклассификации был программно реализован с применением интерпретатора Python 3.6.9. Входными данными программы служат файлы формата *.csv с таблицами морфологических, цветовых, текстурных признаков для каждой из клеток используемой выборки. В выборке представлено девять типов клеток костного мозга. Выходными данными программы мультиклассификации являются значения точности классификации на тестовой выборке, которые отражают совпадение прогнозируемого класса клетки с фактическим (верифицированным) классом клетки. “Эксперимент показал следующие результаты: точность мультиклассификации рассматриваемых типов клеток в среднем составила: 87% на тестовом наборе, 88% на обучающем наборе данных. Проведенное исследование является предварительным. В дальнейшем планируется увеличить число классов клеток, объем выборок различных типов клеток и с уточнением результатов мультиклассификации The use of methods and means of digital image processing in the recognition of types of blood cells and bone marrow to improve the quality of diagnosis of acute leukemia is an urgent scientific and technical task that meets the strategy for the development of artificial intelligence technologies in medicine. The paper proposes an approach to the multiclassification of bone marrow cells in the diagnosis of acute leukemia and minimal residual disease. For experimental studies, a sample of 3284 images of cells was formed, submitted by the Hematopoiesis Laboratory of the National Medical Research Center of Oncology named after V.I. N.N. Blokhin. The proposed approach to the multiclassification of bone marrow cells is based on a binary classification model for each of the studied classes relative to the others. In the work under consideration, binary classification is performed by the support vector machine. The multiclassification method was implemented programmatically using the Python 3.6.9 interpreter. The input data of the program are * .csv files with tables of morphological, color, texture features for each of the cells of the sample used. The sample contains nine types of bone marrow cells. The output data of the multiclassification program are the classification accuracy values on the test sample, which reflect the coincidence of the predicted cell class with the actual (verified) cell class. “The experiment showed the following results: the accuracy of multiclassification of the considered types of cells on average was: 87% on the test set, 88% on the training data set. This study is preliminary. In the future, it is planned to increase the number of classes of cells, the volume of samples of various types of cells and with the refinement of the results of multiclassification

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 400-400 ◽  
Author(s):  
Wolfgang Kern ◽  
Daniela Voskova ◽  
Claudia Schoch ◽  
Wolfgang Hiddemann ◽  
Susanne Schnittger ◽  
...  

Abstract Guiding antileukemic treatment in patients with acute myeloid leukemia (AML) is increasingly based on levels of minimal residual disease (MRD) which can be quantified with high sensitivity by multiparameter flow cytometry (MFC). The optimum checkpoint for determination of MRD during the course of therapy, however, has not yet been determined. We applied MFC using a comprehensive panel of antibodies to identify leukemia-associated aberrant immunophenotypes (LAIPs) at diagnosis and to quantify MRD by individually selected antibody combinations. The prognostic impact of MRD levels was assessed in comparison to cytogenetics and age. Patients received double induction, consolidation, and maintenance therapies and underwent allogeneic stem cell transplantation if they were younger than 60 years and had a matched related donor. In 286 patients with newly diagnosed and untreated AML MFC-based assessment for the presence of LAIP has been performed. The median percentage of LAIP-positive bone marrow cells at diagnosis was 16.04% (range, 2.54%–76.14%). All individual LAIPs were applied to 26 normal bone marrow samples to estimate sensitivity based on the median percentages of LAIP-positive normal bone marrow cells which ranged from 0.00% to 1.01% (median, 0.02%). A total of 550 follow-up samples has been analyzed in these patients at different checkpoints (CP1, up to day 21 after start of therapy, n=85; CP2, day 22–60, n=122; CP3, day 61–120, n=158; CP4, day 121–365, n=137; CP5, after day 365, n=48). In order to adjust for differences in the percentages of LAIP-positive bone marrow cells at diagnosis the logarithmic difference (LD) between diagnosis and follow-up was calculated for each follow-up sample. The median LDs at the respective checkpoints were: CP1, 2.02; CP2, 2.29; CP3, 2.39; CP4, 2.53; and CP5, 2.81. Separation of patients according to the respective median LDs resulted in differences in event-free survival (EFS; CP1: 21.1 vs. 9.1 months, p=0.0711; CP2: 14.2 vs. 9.3 months, p=0.0095; CP3: 30.9 vs. 13.5 months, p=0.0055; CP4: median not reached vs. 14.1 months, p<0.0001; CP5: median not reached vs. 22.5 months, p=0.0001) and overall survival (OS; CP3: median not reached vs. 21.6 months, p=0.0332; CP4: 90% vs. 53% at 2 years, p=0.0058). Cox analysis using the LDs at the different checkpoints as continuous variables confirmed the prognostic impact on EFS (CP2, p=0.002; CP3, p=0.0003; CP4, p<0.0001; CP5, p<0.0001) and revealed an impact also on OS (CP3, p=0.003; CP4, p=0.001; CP5, p=0.029). Cox regression analysis taking into consideration cytogenetics and age as covariates proved the independent prognostic impact of LD at checkpoints 2 to 5 on both EFS and OS with the exception of LD at checkpoint 2 and OS. In fact, LD at checkpoint 5 was the only parameter independently related to EFS and OS. These data suggest that quantification of MRD by MFC in AML results in powerful and independent prognostic parameters. In particular during the first year of treatment MRD levels provide important prognostic information. Clincal trials should use MRD-based stratification in order to assess the efficacy of early treatment intensification in high-risk AML patients.


2021 ◽  
Vol 2058 (1) ◽  
pp. 012033
Author(s):  
V G Nikitayev ◽  
A N Pronichev ◽  
N N Tupitsin ◽  
V Yu Selchuk ◽  
V V Dmitrieva ◽  
...  

Abstract The article considers a new integrated information and measurement system for the diagnosis of acute leukemia and minimal residual disease based on computer microscopy and flow laser cytometry. The system is based on combining the results of computer microscopy in the analysis of bone marrow preparations and the results of flow laser cytofluorimetry. A special feature of the system is the use of artificial intelligence technologies in the recognition of images of bone marrow cells in the computer microscopy subsystem. The work was the result of joint work of the Department of Computer Medical Systems of the National Research Nuclear University "MEPhI" and the Laboratory of Hematopoietic Immunology of the National Medical Research Center of Oncology named after N. N. Blokhin.


2020 ◽  
Vol 169 ◽  
pp. 353-358 ◽  
Author(s):  
Valentin Nikitaev ◽  
Alexander Pronichev ◽  
Evgeney Polyakov ◽  
Olga Chernysheva ◽  
Irina Serebryakova ◽  
...  

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4260-4260
Author(s):  
Alexander Popov ◽  
Tatiana Verzhbitskaya ◽  
Grigory Tsaur ◽  
Egor Shorikov ◽  
Leonid Saveliev ◽  
...  

Abstract Minimal Residual Disease (MRD) monitoring is essential to predict early outcome and further optimize treatment, especially when new approaches to therapy are used. A promising new treatment is the combination of chemotherapy with all trans-retinoic acid (ATRA) for infant acute leukemias. ATRA-mediated maturation of bone marrow cells can lead to the appearance of unusual undifferentiated cells with new immunological characteristics. We investigated the immunophenotypic features of bone marrow cells in infant acute leukemias treated with traditional chemotherapy combined with ATRA. From May 2006 to July 2007, we performed initial and consecutive multicolor flow cytometry assays of bone marrow samples from 4 infants with primary ALL or AML (except M3) treated at our institution. Patient I had BII-ALL, co-expressing CD15, but the majority of his blast cells were CD10(-). Conventional cytogenetics revealed t(4;11) and MLL/AF4 was detected. Early after ATRA administration, we detected MPO(+)TdT(+)-cells and subsequently, CD19, CD10, CD34, CD99 positive cells were found. Moreover, those cells occupied the “blast region” (SSC(low)CD45(dim)) and were seen as an autonomous population on the FSC/SSC dot plot. There was no correlation with the number of CD19(+)MPO(+)-cells and either MRD, measured by multicolor flow cytometry, or the level of the fusion gene transcript performed by the quantitative real-time polymerase chain reaction. In patient II with primary AML-M2, the cells with the same phenotype were also detected after several ATRA courses. Patient III, with primary biphenotypic leukemia, demonstrated total clearance of tumor blasts after the beginning of ATRA treatment with the later appearance of two cells populations: one similar to the phenotype previously described in patients I and II, but additionally expressing CD79a. The second cell population was positive for the cortical thymocytes markers CD7, CD5, CD2, CD4, CD8 and CD1a. This phenotype was observed shortly after ATRA initiation and disappeared with further chemotherapy. Patient IV with primary AML-M7 was switched to BII-ALL after the 3rd ATRA course. Simultaneously, a minor population of biphenotypic cells was observed and later comprised 2 groups: TdT(−)CD99(−)CD45(bright) and TdT(+)CD99(+)CD45(dim) cells. We infer from this observation that the biphenotypic cells had matured. Cortical thymocytes were also detected in this patient for a short period. In all 4 patients we observed an equal distribution of biphenotypic cells on dot plots despite the differences in the primary leukemia phenotypes. This raises the question of a tumor versus an ATRA-mediated origin of the biphenotypic cells that requires further investigation in the patients treated with ATRA. Moreover, we conclude that a more extensive and specific panel of monoclonal antibodies is also required for the full immunophenotypic characterization of infant leukemia.


2021 ◽  
Vol 2058 (1) ◽  
pp. 012043
Author(s):  
V G Nikitayev ◽  
A N Pronichev ◽  
N N Tupitsin ◽  
V Yu Selchuk ◽  
V V Dmitrieva ◽  
...  

Abstract The paper presents approaches to automated classification of bone marrow cells in the diagnosis of acute lymphoblastic leukemia and minimal residual disease using image recognition procedures. The classification methods that show the best accuracy in the recognition of eight types of bone marrow cells were experimentally determined. Recommendations for their use are given.


Author(s):  
Ольга Александровна Медведева ◽  
Святослав Николаевич Простаков ◽  
Николай Николаевич Тупицын ◽  
Александра Дмитриевна Палладина

В статье представлено описание факторов, влияющих на качество формирования базы эталонных изображений клеток костного мозга для диагностики острых лейкозов с применением методов компьютерной микроскопии. Отмечена важность контроля качества подготовки препаратов и микроскопа для применения в автоматизированных системах анализа изображений. Рассмотрены особенности регистрации цифровых микроскопических изображений клеток костного мозга в системах компьютерной микроскопии. Исследовано влияние фокусировки оптической системы микроскопа и уровня освещения препарата на формирование цифровых изображений клеток костного мозга. Установлены требования к условиям регистрации цифровых изображений, используемых в автоматизированных системах микроскопического анализа препаратов костного мозга. Предложена концептуальная модель базы эталонных изображений костного мозга, являющаяся основой для разработки инструментов эффективного распознавания клеток костного мозга в системах компьютерной микроскопии. Следование указанным требованиям к регистрации изображений призвано обеспечить надлежащее качество эталонной базы, что имеет непосредственной влияние на повышение точности и достоверности медицинской диагностики с применением методов компьютерной микроскопии. Результаты работы могут быть использованы в системах поддержки принятия врачебных решений при диагностике острых лейкозов The article describes the factors affecting the quality of the formation of a database of reference images of bone marrow cells for the diagnosis of acute leukemia using computer microscopy methods. The importance of quality control of specimen and microscope preparation for use in automated image analysis systems is noted. The features of registration of digital microscopic images of bone marrow cells in computer microscopy systems are considered. The effect of focusing of the optical system of the microscope and the level of illumination of the specimen on the formation of digital images of bone marrow cells is investigated. The requirements for the conditions of registration of digital images used in automated systems of microscopic analysis of bone marrow preparations have been established. A conceptual model of the base of reference images of bone marrow is proposed. It is the basis for the development of tools for effective recognition of bone marrow cells in computer microscopy systems. Following the specified requirements for image registration is designed to ensure the proper quality of the reference base of images, which has a direct impact on improving the accuracy and reliability of medical diagnostics using computer microscopy. The results of the work can be used in medical decision support systems for the diagnosis of acute leukemia


1989 ◽  
Vol 7 (3) ◽  
pp. 338-343 ◽  
Author(s):  
M Bregni ◽  
S Siena ◽  
A Neri ◽  
R Bassan ◽  
T Barbui ◽  
...  

We have developed an assay for the detection of malignant residual cells in the bone marrow from patients with B- or T-lineage acute lymphoblastic leukemia (ALL) in clinical remission. This assay involves an immune selection step followed by immunoglobulin or T-cell receptor gene rearrangement analysis and allows the detection of one contaminating tumor cell out of 1,000 normal bone marrow cells. We have examined the bone marrow of 11 patients with adult ALL in remission over a 24-month period. Five patients relapsed in the bone marrow and one in the CNS. The assay allowed the detection of minimal residual disease in four of five patients that subsequently relapsed in the bone marrow, 1.5 to 9 months before the relapse became morphologically and clinically manifest. Residual disease was not found in the bone marrow from patients in continuous remission and from the single patient who relapsed in the CNS. We conclude that the ability of the assay described here to detect minimal residual disease with high specificity can provide information for further understanding of the biology of ALL and hopefully for the clinical management of patients with this disease.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2025-2025
Author(s):  
Wolfgang Kern ◽  
Daniela Voskova ◽  
Claudia Schoch ◽  
Wolfgang Hiddemann ◽  
Susanne Schnittger ◽  
...  

Abstract The quantification of minimal residual disease (MRD) by multiparameter flow cytometry (MFC) using triple staining has been shown to yield prognostic information independent of other parameters in patients with acute myeloid leukemia (AML). Due to the immunophenotypic heterogeneity of AML the application of 5-fold staining may result in a better characterization of the leukemia-associated aberrant immunophenotype (LAIP) and thus in an improved sensitivity of the method as compared to triple staining. We analyzed bone marrow samples from 114 patients with newly diagnosed and untreated AML by MFC using a comprehensive antibody panel with 5-fold combinations. Sensitivity was estimated by quantification of LAIP-positive cells for each LAIP in 18 normal bone marrow samples. In each patient at least one LAIP was identified (total, 203 LAIPs). The LAIPs were present on a median of 15.88% of the bone marrow cells at diagnosis (range, 2.11% to 79.64%). The median number of normal bone marrow cells displaying the LAIPs ranged from 0.001% to 0.065% (median, 0.010%). As a result, the logarithmic difference (LD) in LAIP-positive cells between leukemic and normal bone marrow amounted to a median of 3.33 (range, 1.96 to 4.88). Similarly, if only the most sensitive LAIP was considered for each patient the median frequencies of LAIP-positive cells were 14.07% (range, 2.11% to 77.57%) in leukemic bone marrow and 0.010% (range, 0.001% to 0.065%) in normal bone marrow. Importantly, however, in this setting the resulting LD amounted to a median of 3.45 (range, 1.96 to 4.88). In order to estimate the impact of applying 5-fold staining on the sensitivity the information of each of the applied colors was skipped once while the results of the other four colors, respectively, were used. Skipping one color resulted in an increase of LAIP-positive normal bone marrow cells (median, 0.050%; range, 0.001% to 3.6%) while the percentages of LAIP-positive leukemic cells changed only marginally (median, 22.65%; range, 2.25% to 90.06%). The gain in LD by applying 5-fold staining in comparison to 4-fold staining amounted to a median of 0.58 (maximum gain, 3.14). In 32 patients a total of 120 follow-up samples have been analyzed appyling the combination of antibodies that allowed the best LAIP definition. The LD from diagnosis to follow-up amounted to a median of 2.82 (range, 0.77 to 4.82). Clinical follow-up data is available in 26 of these 32 patients. MRD assessment after completion of consolidation therapy has been performed in 15 patients. The median LD between diagnosis and follow-up assessment is 2.84 (range, 1.07 to 4.33). Separating patients according to this median LD identified a group of patients with no relapses yet (LD >2.84) while patients with an LD <2.84 had an event-free survival of only 50% at one year (p=0.075). These data confirm that flow cytometrically-based assessment of MRD is feasible in AML and results in prognostic information. It is suggested that the application of 5-fold staining significantly improves the sensitivity and thereby the overall accuracy of the method.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 933-933
Author(s):  
Guido Tricot ◽  
Matteo Carrabba ◽  
Bart Barlogie ◽  
Joshua Epstein ◽  
John Shaughnessy ◽  
...  

Abstract TT-2 represents a very intensive treatment approach for newly diagnosed myeloma patients consisting of hematopoietic growth factor-dependent induction therapy (VAD, DCEP, CAD, DCEP); followed by melphalan 200 mg/m2-based tandem autotransplant; 4 quarterly consolidation chemotherapy cycles with D-PACE; and interferon alpha maintenance with added dexamethasone pulsing during the first year. A stringently defined hematologic CR (immunofixation negative, normal bone marrow aspirate and biopsy, and absence of a light-chain restricted aneuploid population of bone marrow plasma cells by DNA/cIg flow cytometry) was obtained in 48% of the first 446 patients enrolled on TT-2. A CR defined as such probably reflects a detection threshold of 108–109 tumor cells. CDR3-PCR to evaluate minimal residual disease (MRD) in myeloma has revealed m-CR in 50% of 40 reported allotransplant cases compared to approximately 15% among 75 reported autotransplants myeloma. We evaluated the frequency of m-CR in 20 TT-2 patients with a qualitative PCR for CDR3, which can detect 1 myeloma cell in 105–106 normal bone marrow cells (Corradini et al. J Clin Oncol 1999, 17: 208). CDR3 probes were generated from RNA of CD138 immunogenetic bead-purified plasma cells obtained at diagnosis. Light-density (<1.077 g/cm3) bone marrow cells served as the source of DNA post-therapy to assess MRD. The quality of DNA was determined by amplification of the p53 exon 6 sequence on all CDR3-PCR negative cases. At the time of CDR3-PCR analysis, 13 patients were in hematologic CR, 1 in near CR (immunofixation positivity as the only evidence of disease), 4 in partial remission (PR) (bone marrow < 5% plasma cells, decrease in serum M protein ≥ 75% and in urine M protein ≥ 90%) and two had less than a PR. Four patients were tested for MRD prior to the first transplant (2 < PR, 1 PR, 1 CR), two prior to the second transplant (2 PR) and 14 at a median of 21 months (range 6 months to 2 years) after the second transplant (12 CR, 1 near CR, 1 PR). Six of the 13 CR patients had abnormal metaphase cytogenetics at diagnosis, including 5 with deletion of chromosome 13. A m-CR was observed in 10/13 (77%) hematologic CR patients, including 4/6 with abnormal cytogenetics and 6/7 with normal cytogenetics. P53 exon 6 amplification was seen in all patients who were CDR3-PCR negative. Not unexpectedly, all seven patients failing to achieve a stringently defined hematologic CR had persistent disease as assessed by CDR3-PCR. Our results suggest that high intensity therapy as applied in TT-2 can indeed achieve a more marked tumor cytoreduction as reflected by a higher m-CR rate than previously reported with autotransplantation also in patients with baseline abnormal metaphase cytogenetics, and that the m-CR rate appears to be at least equivalent to that observed after allotransplantation. It remains to be shown whether achieving a m-CR will result in prolonged survival and a potential of cure in myeloma as has been shown convincingly for other hematologic malignancies. An additional 35 hematologic CR patients have samples available for CDR3-PCR analysis so that, at the time of presentation, a more definitive assessment of TT-2’s potential to effect a m-CR can be presented.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5097-5097
Author(s):  
Atsushi Marumo ◽  
Hiroki Yamaguchi ◽  
Yuho Najima ◽  
Kensuke Usuki ◽  
Shinichi Kako ◽  
...  

Background: As recurrence of acute myeloid leukemia (AML) is difficult to predict, it is important to detect it by measuring minimal residual disease (MRD). PML-RARA, RUNX-RUNX1T1, CBFB-MYH11 are regarded as the reliable MRD markers. However, in AML with normal karyotype and many other forms, no MRD markers have been established. NPM1 mutations, occurring in approximately 30% of adult AML cases, and 50-60% of AML cases with normal karyotype, represent one of the most frequent mutations in AML. Recently, NPM1 mutation is reported to be useful in assessing MRD. We undertook a retrospective and prospective investigation of the usefulness of NPM1 mutation as an MRD marker in Japanese patients with AML. Methods: The subjects were 38 NPM1-mutated AML patients with first hematological remission at several hospitals related to our institution between 2001 and 2018. This study was approved by the ethics committee of Nippon Medical School and the informed consents were obtained from all patients, according to the Declaration of Helsinki. We analyzed peripheral blood cells or bone marrow cells at diagnoses, and evaluated only bone marrow cells after diagnoses. Detection of NPM1 mutation was carried out using allele-specific real time PCR following creation of a complementary primer. After dilution of the samples, sensitivity to TCTG, CATG, and CCTG was found to be 0.001%. The NPM1 mutant copies were qualified only at successful amplification of internal control. Results: The median age of the patients was 58 years (18-79 years). There were 32 cases with intermediate cytogenetic prognosis and 6 cases with unclear chromosomal profile. Of the 38 cases, 14 cases (37%) were FLT3-ITD-positive and allogeneic hematopoietic stem cell transplantation was carried out in 14 cases (37%). The base sequence was TCTG in 36 cases and CCTG in 2 cases. Persistence of NPM1-mutatation was present in 25 patients with first hematological remission (66%). Compared with patients with MRD negative, patients with MRD positive were associated with DNMT3A mutation (MRD positive 12/25 vs MRD negative 0/13, p=0.003). The rate of relapse in patients with MRD positive was significantly higher than those of in patients with MRD negative (MRD positive 76% vs MRD negative 23%, p=0.004). The rates of relapse free survival (RFS) and overall survival (OS) in patients with MRD positive were significantly lower than those in patients with MRD negative (RFS at 2 years: MRD positive 14% vs MRD negative 86% p=0.003; Figure 1, OS at 2 years: MRD positive 25% vs MRD negative 93%, p<0.001). In FLT3-ITD negative group, the rates of RFS in patients with MRD positive were significantly lower than those in patients with MRD negative. (RFS at 2 years: MRD positive 21% vs MRD negative 92% p=0.001; Figure 1). Conclusion: The presence of MRD with NPM1 mutation is significantly associated with relapse and it is useful to decide their treatment strategy. Especially, there is the usefulness of NPM1 mutation as an MRD marker in NPM1 positive Flt3-ITD negative AML patients who are generally classified as favorable risk. According to previous reports, it is known that NPM1-mutated AML sometimes relapse with losing NPM1 mutations. However, in this study, all NPM1-mutated AML relapse without losing NPM1 mutations. We need to collect more patients and are going to confirm whether there are patients who relapse with losing NPM1 mutations or not. We plan to analyze the genetic background of MRD positive and negative patients with next-generation sequencing. We are going to announce the genetic characteristics in addition to this result at ASH. Disclosures Usuki: Astellas Pharma Inc: Research Funding, Speakers Bureau; Daiichi Sankyo Co., Ltd.: Research Funding, Speakers Bureau. Kako:Bristol-Myers Squibb: Honoraria; Pfizer Japan Inc.: Honoraria. Inokuchi:Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria; Celgene: Honoraria; Pfizer: Honoraria.


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