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This study proposes a novel methodology for directly training response surfaces of torque and magnet flux density distributions of interior permanent magnet synchronous motors (IPMSMs) under specified input conditions and predicting the speed-torque characteristics or torque wave. Existing models have low prediction accuracy when simultaneously integrating shape information and current conditions. To overcome this challenge and improve the prediction of motor characteristics, a new deep learning (DL) model that combines deep operator networks and convolutional neural networks is proposed. This advanced approach greatly improves the accuracy of motor characteristic predictions across varying current levels and rotational angles, achieving an 89.6% increase in accuracy compared to comparative methods. The model is successfully applied to parameter and topology optimization (TO), effectively maximizing the speed-torque characteristics of IPMSMs.

This study proposes a novel methodology for topology optimization, employing an explainable deep neural network (XDNN). This innovative approach utilizes Shapley additive explanations (SHAPs), a tool designed to elucidate the predictive reasoning of convolutional neural networks (CNNs). The contributing regions to the characteristics are revealed by SHAP and topology optimization is performed in restricted regions to reduce the computational cost during the search while ensuring an efficient search. As a practical demonstration of the efficacy of the proposed method, it is applied to an interior permanent magnet synchronous motor. The results comprehensively demonstrate the effectiveness and potential implications of the novel methodology.

This study proposes a novel approach using convolutional neural networks (CNNs) to predict the torque characteristics of an interior permanent magnet (IPM) motor. The proposed method allows CNNs to predict the average torque and torque amplitude under various magnet configurations using the magnetic flux density distribution of the stator core. The proposed method, compared with methods trained only on the magnetic flux density distributions of the rotor core, improves the generalization performance in predicting torque characteristics. This significantly reduces the training data. In addition, the topology optimization (TO) time using the proposed method is reduced by 45% compared with the conventional method that only utilizes the finite element method (FEM).

Monitoring of Immune Responses Following Mogamulizumab-Containing Treatment in Patients with Adult T-Cell Leukemia-Lymphoma (ATL) (MIMOGA) is a multicenter prospective observational study to establish the most effective and safe treatment strategy using mogamulizumab for ATL patients (UMIN000008696). Mogamulizumab-naive patients were enrolled (n = 102), of whom 101 received mogamulizumab-containing treatment (68 acute, 18 lymphoma, 12 chronic, and 3 smoldering subtypes). At enrollment, there was a significant inverse correlation between serum soluble interleukin-2 receptor (sIL-2R) levels and percentages of Tax-specific cytotoxic T lymphocytes (Tax-CTLs) in the entire lymphocyte population or in the CD8+ T cell subset, but there was not a correlation with cytomegalovirus pp65–specific cytotoxic T lymphocytes (CMV-CTLs). The overall response rate was 65%, and median progression-free survival and overall survival (OS) were 7.4 and 16.0 months, respectively. A higher percentage of Tax-CTLs, but not CMV-CTLs, within the entire lymphocyte population or in the CD8+ T cell subset was significantly associated with longer survival. Multivariate analysis identified the clinical subtype (acute or lymphoma type), a higher sIL-2R level, and a lower percentage of CD2−CD19+ B cells in peripheral blood mononuclear cells as significant independent unfavorable prognostic factors for OS. This indicates that a higher percentage of B cells might reflect some aspect of a favorable immune status leading to a good outcome with mogamulizumab treatment. In conclusion, the MIMOGA study has demonstrated that mogamulizumab exerts clinically meaningful antitumor activity in ATL. The patient’s immunological status before mogamulizumab was significantly associated with treatment outcome. Further time series immunological analyses, in addition to comprehensive genomic analyses, are warranted.

Monitoring of Immune Responses Following Mogamulizumab-Containing Treatment in Patients with Adult T-Cell Leukemia-Lymphoma (ATL) (MIMOGA) is a multicenter prospective observational study to establish the most effective and safe treatment strategy using mogamulizumab for ATL patients (UMIN000008696). Mogamulizumab-naive patients were enrolled (n = 102), of whom 101 received mogamulizumab-containing treatment (68 acute, 18 lymphoma, 12 chronic, and 3 smoldering subtypes). At enrollment, there was a significant inverse correlation between serum soluble interleukin-2 receptor (sIL-2R) levels and percentages of Tax-specific cytotoxic T lymphocytes (Tax-CTLs) in the entire lymphocyte population or in the CD8+T cell subset, but there was not a correlation with cytomegalovirus pp65–specific cytotoxic T lymphocytes (CMV-CTLs). The overall response rate was 65%, and median progression-free survival and overall survival (OS) were 7.4 and 16.0 months, respectively. A higher percentage of Tax-CTLs, but not CMV-CTLs, within the entire lymphocyte population or in the CD8+T cell subset was significantly associated with longer survival. Multivariate analysis identified the clinical subtype (acute or lymphoma type), a higher sIL-2R level, and a lower percentage of CD2−CD19+B cells in peripheral blood mononuclear cells as significant independent unfavorable prognostic factors for OS. This indicates that a higher percentage of B cells might reflect some aspect of a favorable immune status leading to a good outcome with mogamulizumab treatment. In conclusion, the MIMOGA study has demonstrated that mogamulizumab exerts clinically meaningful antitumor activity in ATL. The patient's immunological status before mogamulizumab was significantly associated with treatment outcome. Further time series immunological analyses, in addition to comprehensive genomic analyses, are warranted.

Adult T-cell leukemia/lymphoma (ATL) is a human T-cell leukemia virus 1 (HTLV-1)-induced malignancy of mature T lymphocytes with poor outcomes. Brentuximab vedotin (BV), which is an anti-CD30 antibody conjugated with monomethyl auristatin E, is included in the treatment of CD30-positive ATL, but there is no useful therapeutic marker for BV. Soluble CD30 (sCD30) in serum is increased in aggressive-type ATL at diagnosis, but the effects of extracellular CD30 on BV-induced cell death in ATL remain unclear. Similarly, a disintegrin and metalloproteinase (ADAM) 10 and 17 have CD30 sheddase activity in anaplastic large cell lymphoma, but this activity is unknown in ATL. The present study showed that sCD30 concentrations were related to BV activity in ATL-related cell lines. Extracellular vesicles (EVs) such as exosomes containing CD30 also inhibited BV activity. Additionally, the knockdown of ADAM10/17 significantly reduced sCD30 concentrations with increased cell death by BV. Our results suggest that ADAM10/17 are involved in sCD30 production in ATL. Moreover, endogenous extracellular CD30, such as sCD30 shed by ADAM10/17, and CD30-positive EVs may be responsible for the BV-induced cell death. Correctively, extracellular CD30 concentrations, including EV, may be useful as biomarkers for BV therapy in ATL.

Reactivation of hepatitis B virus (HBV) infection is a potentially lethal complication, but may be preventable in patients with chronic HBV infection or resolved HBV infection who receive systemic chemotherapy.The risk of HBV reactivation (HBVR) depends on not only HBV infectious status but also type of systemic chemotherapy. An anti-CCR4 antibody, mogamulizumab (Moga), has been developed for the treatment of peripheral T-cell lymphomas. Moga is known to suppress CCR4-positive regulatory T cells and helper T cells, which can lead to immunological dysfunction. However, there is little evidence regarding the risk of HBVR in patients with chronic HBV infection or resolved HBV infection who receive Moga-containing systemic chemotherapy. We conducted a retrospective observational study to evaluate the risk of HBVR and clinical outcome in those patients. METHODS & MATERIALS: Patients treated with Moga-containing chemotherapy for T-cell lymphoma between May 2012 and March 2021, who were chronic HBV infection (defined as seropositive for HBsAg) or resolved HBV infection (defined as seronegative for HBsAg, but seropositive for anti-HBc or anti-HBs), were included. The primary endpoint was the rate of HBVR; HBVR in HBsAg-positive patients was defined as any of the following three criteria: 1) 2 log or more increase in HBV DNA from baseline, 2) 3.0 Log IU/ml or more of HBV DNA in patients with undetectable HBV DNA at baseline, 3) 4.0 Log IU/ml or more of HBV DNA in patients not available for HBV DNA at baseline. HBVR in HBsAg-negative patients was defined as any of following three criteria: 1) detectable for HBV DNA in patients with undetectable HBV DNA at baseline, 2) 1.3 Log IU/mL or more of HBV DNA in patients not available for HBV DNA at baseline, 3) seroconversion of HBsAg. RESULTS: A total of 23 HBsAg-positive patients and 246 resolved HBV-infected patients were retrospectively reviewed. Among the 23 HBsAg-positive patients, the median age was 65 years (interquartile range [IQR], 63-73) and 19 patients (82%) had adult T-cell leukemia-lymphoma (ATL). Baseline HBV DNA was undetectable level, detectable not quantifiable, and detectable in 9 (39%), 2 (9%), and 12 (52%) patients, respectively. All 23 HBsAg-positive patients received anti-HBV prophylaxis prior to Moga treatment. One of 23 (4.3%) patients experienced HBVR who led to HBV-related hepatitis. Among the 241 patients with resolved HBV infection, the median age was 65 years (IQR, 63-73) and 223 patients (91%) had ATL. Baseline serostatus of anti-HBc and anti-HBs were as follows: anti-HBc positive and anti-HBs positive in 177 patients (72%), anti-HBc-positive but anti-HBs negative in 50 (20%), the remaining 9 were anti-HBc negative but anti-HBs positive. Baseline HBV DNA was undetectable in 233 (95%), detectable not quantifiable in 5 (2%), and the remaining 3 were detectable for HBV DNA. Only 3 patients received anti-HBV prophylaxis. HBVR occurred in 11 patients, and the 2-year cumulative HBVR rate was 3.5% (95% CI, 1.6-16.5). Among the 11 patients with HBVR, the median peak HBV DNA level was 2.1 Log IU/mL (IQR, 1.7-5.0), the median time from first dose of Moga to HBVR was 140 days (IQR, 82-765) and 2 had HBV-related hepatitis. CONCLUSION: Our current study showed that the risk of HBVR was 4.3% (1 of 23) among HBsAg-positive patients with antiviral prophylaxis and 4.6% (11 of 238) among resolved HBV-infected patients without antiviral prophylaxis following Moga-containing chemotherapy. Anti-HBV prophylaxis and HBV DNA monitoring guided preemptive anti-HBV therapy are recommended to prevent HBV-related hepatitis for HBsAg-positive and resolve HBV-infected patients, respectively.

Standard treatment for untreated advanced-stage follicular lymphoma is rituximab plus chemotherapy. The incidence of histological transformation of follicular lymphoma has been reported only in heterogeneously treated populations and rarely with long-term follow-up. Additionally, the incidence of secondary malignancies after treatment, without high-dose therapy for follicular lymphoma, is largely unknown. The aim of our study was to assess progression-free survival, overall survival, incidence of secondary malignancies, and incidence of histological transformation in a 10-year follow-up analysis of the JCOG0203 trial.

Adult T-cell leukemia (ATL) caused by human T-cell leukemia virus type 1 (HTLV-1) infection, occurs in 2% to 4% of the HTLV-1 carriers with a long latent period, suggesting that additional alterations participate in the development of ATL. To characterize and identify novel markers of ATL, we examined the expression profiles of more than 12 000 genes in 8 cases of acute-type ATL using microarray. One hundred ninety-two genes containing interleukin 2 (IL-2) receptor α were up-regulated more than 2-fold compared with CD4+and CD4+CD45RO+T cells, and tumor suppressor in lung cancer 1 (TSLC1), caveolin 1, and prostaglandin D2 synthase showed increased expression of more than 30-fold. TSLC1 is a cell adhesion molecule originally identified as a tumor suppressor in the lung but lacks its expression in normal or activated T cells. We confirmed ectopic expression of the TSLC1 in all acute-type ATL cells and in 7 of 10 ATL- or HTLV-1–infected T-cell lines. Introduction of TSLC1 into a human ATL cell line ED enhanced both self-aggregation and adhesion ability to vascular endothelial cells. These results suggested that the ectopic expression of TSLC1 could provide a novel marker for acute-type ATL and may participate in tissue invasion, a characteristic feature of the malignant ATL cells.

Adult T-cell leukemia (ATL) caused by human T-cell leukemia virus type 1 (HTLV-1) infection, occurs in 2% to 4% of the HTLV-1 carriers with a long latent period, suggesting that additional alterations participate in the development of ATL. To characterize and identify novel markers of ATL, we examined the expression profiles of more than 12 000 genes in 8 cases of acute-type ATL using microarray. One hundred ninety-two genes containing interleukin 2 (IL-2) receptor α were up-regulated more than 2-fold compared with CD4+ and CD4+CD45RO+ T cells, and tumor suppressor in lung cancer 1 (TSLC1), caveolin 1, and prostaglandin D2 synthase showed increased expression of more than 30-fold. TSLC1 is a cell adhesion molecule originally identified as a tumor suppressor in the lung but lacks its expression in normal or activated T cells. We confirmed ectopic expression of the TSLC1 in all acute-type ATL cells and in 7 of 10 ATL- or HTLV-1–infected T-cell lines. Introduction of TSLC1 into a human ATL cell line ED enhanced both self-aggregation and adhesion ability to vascular endothelial cells. These results suggested that the ectopic expression of TSLC1 could provide a novel marker for acute-type ATL and may participate in tissue invasion, a characteristic feature of the malignant ATL cells.

We have identified a novel gene MEL1(MDS1/EVI1-like gene 1) encoding a zinc finger protein near the breakpoint of t(1; 3)(p36;q21)-positive human acute myeloid leukemia (AML) cells. Here, we studied the structure, expression pattern, and function of MEL1in leukemia cells. In this study, we have identified 3 transcription start sites, 1 in exon 1 and 2 in exon 2, and 2 kinds of translation products, 170 kDa (MEL1) and 150 kDa (MEL1S). Notably, the 150-kDa band of MEL1S was detected mainly in the t(1;3)(p36;q21)-positive AML cells. By immunoblot analysis and proteolytic mapping, it is suggested that the 150-kDa band of MEL1S in the leukemia cells is translated from the internal initiation codon ATG597 in exon 4 and is mostly lacking the amino-terminal PR domain of MEL1. By the cyclic amplification and selection of targets (CASTing) method for identifying consensus sequences, it was shown that the consensus sequences of MEL1 were included in 2 different consensus sequences for DNA-binding domain 1 and 2 (D1-CONS and D2-CONS) of EVI1. In reporter gene assays, MEL1S activated transcription via binding to D2-CONS; however, the fusion of MEL1 or MEL1S to GAL4 DNA-binding domain (DBD) made them GAL4 binding site–dependent transcriptional repressors. Moreover, overexpression of MEL1Sblocked granulocytic differentiation induced by granulocyte colony-stimulating factor (G-CSF) in interleukin-3 (IL-3)–dependent murine myeloid L-G3 cells, while MEL1could not block the differentiation. Thus, it is likely that overexpression of the zinc finger protein lacking the PR domain (EVI1and MEL1S)in the leukemia cells is one of the causative factors in the pathogenesis of myeloid leukemia.

We have identified a novel gene MEL1 (MDS1/EVI1-like gene 1) encoding a zinc finger protein near the breakpoint of t(1; 3)(p36;q21)-positive human acute myeloid leukemia (AML) cells. Here, we studied the structure, expression pattern, and function of MEL1 in leukemia cells. In this study, we have identified 3 transcription start sites, 1 in exon 1 and 2 in exon 2, and 2 kinds of translation products, 170 kDa (MEL1) and 150 kDa (MEL1S). Notably, the 150-kDa band of MEL1S was detected mainly in the t(1;3)(p36;q21)-positive AML cells. By immunoblot analysis and proteolytic mapping, it is suggested that the 150-kDa band of MEL1S in the leukemia cells is translated from the internal initiation codon ATG597 in exon 4 and is mostly lacking the amino-terminal PR domain of MEL1. By the cyclic amplification and selection of targets (CASTing) method for identifying consensus sequences, it was shown that the consensus sequences of MEL1 were included in 2 different consensus sequences for DNA-binding domain 1 and 2 (D1-CONS and D2-CONS) of EVI1. In reporter gene assays, MEL1S activated transcription via binding to D2-CONS; however, the fusion of MEL1 or MEL1S to GAL4 DNA-binding domain (DBD) made them GAL4 binding site–dependent transcriptional repressors. Moreover, overexpression of MEL1S blocked granulocytic differentiation induced by granulocyte colony-stimulating factor (G-CSF) in interleukin-3 (IL-3)–dependent murine myeloid L-G3 cells, while MEL1 could not block the differentiation. Thus, it is likely that overexpression of the zinc finger protein lacking the PR domain (EVI1 and MEL1S) in the leukemia cells is one of the causative factors in the pathogenesis of myeloid leukemia.

Adult T-cell leukemia/lymphoma (ATL) is a peripheral T-cell malignancy caused by human T-lymphotropic virus type I (HTLV-1). HTLV-1 is endemic to the southwestern region of Japan, Caribbean basin, Central and South America, and western Africa. A previous report by the Japan Clinical Oncology Group-Lymphoma Study Group (JCOG-LSG) identified five prognostic factors: advanced performance status (PS), high lactic dehydrogenase (LDH), age of 40 years or older, total involved lesions, and hypercalcemia, based on an analysis of 854 patients with newly diagnosed ATL registered between 1983 and 1987. The JCOG-LSG then proposed 4 clinical subtypes: acute, lymphoma, chronic, and smoldering types. In general, the prognosis of acute and lymphoma type ATL is similarly very poor, whereas that of the chronic and smouldering types is better. It has come to the attention of clinicians that there are diverse clinical courses and treatment outcomes among patients with acute and lymphoma type ATL. Therefore, it is necessary to establish a prognostic index (PI) for a risk-adapted approach and improving the quality of clinical trials. The aim of this study was to develop the first PI for acute and lymphoma type ATL (ATL-PI).We conducted a nationwide retrospective survey of ATL patients who were newly diagnosed between January 2000 and December 2009, and 1,270 patients with acute and lymphoma type were registered. Fully eligible 807 individuals excluding patients who have received allogeneic hematopoietic stem cell transplantation were used for this analysis, and randomly split the dataset into training (n=404) and validation (n=403) samples. We applied a multivariable fractional polynomial model using continuous variables, and then developed the simplified one using dichotomizing variables.The overall median survival time (MST) for 807 patients was 7.7 months. The Ann Arbor stage (I - II vs. III - IV), performance status (0–1 vs. 2–4), and the three continuous variables of age, serum albumin, and soluble interleukin-2 receptor (sIL-2R) were identified as independent prognostic factors in the training sample. Using these variables, a prognostic model was devised to identify three groups at different levels of risk. In the validation sample, MSTs were 3.6, 7.3, and 16.2 months for patients at high, intermediate, and low risk, respectively (p<0.0001).ATL-PI = 0.65 (if Stage = III or IV) + 0.35 (if PS > 1) + 0.016 × Age (years) − 0.36 × Albumin (g/dL) + 0.37 × log10 (sIL2R (U/mL))To make the scoring system simpler and clinically practicable, we also simplified the original ATL-PI by dichotomizing age at 70 years, serum albumin at 3.5 g/dL, and sIL-2R at 20,000 U/mL and subsequently fitted a multivariate Cox model based on these dichotomizations in the training sample. Then, we derived a simplified ATL-PI as follows:Simplified ATL-PI = 2 (if Stage = III or IV) + 1 (if PS > 1) + 1 (if Age > 70) + 1 (if Albmin < 3.5) + 1 (if sIL2R > 20,000)The scores from 0 to 2 were categorized into low risk group, 3 and 4 into intermediate risk, and from 5 to 6 into high risk group. This classification yielded a good separation of OS curves (p<0.0001), and high concordance to the original ATL-PI in the validation sample.We identified 5 prognostic factors in acute and lymphoma type ATL using a multivariable fractional polynomial model, and further simplified it with minimal loss of the original index. The ATL-PI enables us to distinguish 3 different groups by predicting OS at the time of diagnosis. The ATL-PI, the first PI for acute and lymphoma type ATL, may be a promising platform in consideration of the choice of optimal treatment by risk-stratification and for well-controlled clinical trials.No relevant conflicts of interest to declare.

Abstract 1582This icon denotes a clinically relevant abstract

Cytogenetic analyses and their correlation with clinical features are still limited in mature T-cell malignancies. The cytogenetics of adult T-cell leukemia/lymphoma (ATLL) is complicated by many structural and numerical abnormalities of chromosomes. Thus, it is occasionally difficult to define karyotype of ATLL only by chromosomal banding method. Using multicolor spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH), we performed molecular-cytogenetic studies on 38 patients with adult T-cell leukemia/lymphoma (ATLL) and 7 established cell lines. In SKY analysis, chromosomal bands involved in rearrangements were identified based on the inverted images of DAPI staining. Chromosome no.7 (25 cases) and no.14 (30) were frequently involved in structural rearrangements including translocations, inversions, insertions, isochromosomes, and deletions. Breakages frequently occurred at 10p11-13 (21 cases, 46.6%), and 14q11.2 (16, 35.6%), 14q32 (12, 26.7%), 7q22 (10, 22.2%), 9q22 (10, 22.2%), 13q14 (9, 20.0%), 22p11 (8, 17.7%), 8p11 (7, 15.5%), 18p11 (7, 15.5%), 21q22 (7, 15.5%) and 19q13 (6, 13.3%). Recurrent partners associated with 10p11.2-13 rearrangements were 21q22 (3 cases), 13q14 (2) and 14q32.1 (2). Partner chromosomal breakpoints involving 14q11.2 rearrangements were 14q32 (3 cases), 8p11.2-21 (3), and 11q13.3 (2), while those involved in 14q32 rearrangements were 14q11 (3) and 10p11-13 (2). Using FISH with 37 bacterial artificial chromosome clones, we analyzed breakpoints at 10p11.2-13 in two cell lines KOB4 and KK1 and one patient (HH) by walking a segment ranging from 10p13 to 10p11.2. Among 37 BAC clones used as FISH probes, 9 were assigned to 10p15, 3 to 10p14-13, and the remaining 25 to 10p11.2-12. Large genomic deletions were detected at 10p11.2 on der(10) in two cell lines. In patient HH, a homozygous deletion was identified at 10p11.2, spanning the region of 1 Mb in size. Chromosome 14q32 translocation was associated with shorter survival (median survival time; 4.2 months vs. 8.0 months), although statistically not significant. As for 10p11.2-13 and 14q11.2 rearrangements, there was no significant difference of survival between patients with and without respective abnormalities. In conclusion, SKY and FISH analysis identified recurrent chromosomal rearrangements and a homozygous deletion at 10p11.2 in ATLL. Our molecular analysis is now focusing on this genomic region to clone genes associated with development of ATLL.

Cytogenetic analyses and their correlation with clinical features are still limited in mature T-cell malignancies. The cytogenetics of adult T-cell leukemia/lymphoma (ATLL) is complicated by many structural and numerical abnormalities of chromosomes. Thus, it is occasionally difficult to define karyotype of ATLL only by chromosomal banding method. Using multicolor spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH), we performed molecular-cytogenetic studies on 38 patients with adult T-cell leukemia/lymphoma (ATLL) and 7 established cell lines. In SKY analysis, chromosomal bands involved in rearrangements were identified based on the inverted images of DAPI staining. Chromosome no.7 (25 cases) and no.14 (30) were frequently involved in structural rearrangements including translocations, inversions, insertions, isochromosomes, and deletions. Breakages frequently occurred at 10p11-13 (21 cases, 46.6%), and 14q11.2 (16, 35.6%), 14q32 (12, 26.7%), 7q22 (10, 22.2%), 9q22 (10, 22.2%), 13q14 (9, 20.0%), 22p11 (8, 17.7%), 8p11 (7, 15.5%), 18p11 (7, 15.5%), 21q22 (7, 15.5%) and 19q13 (6, 13.3%). Recurrent partners associated with 10p11.2-13 rearrangements were 21q22 (3 cases), 13q14 (2) and 14q32.1 (2). Partner chromosomal breakpoints involving 14q11.2 rearrangements were 14q32 (3 cases), 8p11.2-21 (3), and 11q13.3 (2), while those involved in 14q32 rearrangements were 14q11 (3) and 10p11-13 (2). Using FISH with 37 bacterial artificial chromosome clones, we analyzed breakpoints at 10p11.2-13 in two cell lines KOB4 and KK1 and one patient (HH) by walking a segment ranging from 10p13 to 10p11.2. Among 37 BAC clones used as FISH probes, 9 were assigned to 10p15, 3 to 10p14-13, and the remaining 25 to 10p11.2-12. Large genomic deletions were detected at 10p11.2 on der(10) in two cell lines. In patient HH, a homozygous deletion was identified at 10p11.2, spanning the region of 1 Mb in size. Chromosome 14q32 translocation was associated with shorter survival (median survival time; 4.2 months vs. 8.0 months), although statistically not significant. As for 10p11.2-13 and 14q11.2 rearrangements, there was no significant difference of survival between patients with and without respective abnormalities. In conclusion, SKY and FISH analysis identified recurrent chromosomal rearrangements and a homozygous deletion at 10p11.2 in ATLL. Our molecular analysis is now focusing on this genomic region to clone genes associated with development of ATLL.