Duodenal Papillary Metastasis of Lung Cancer with Bleeding Controlled by Endoscopic Treatment and Systemic Osimertinib Therapy: Case Report.

Introduction: Solid organ malignancies rarely metastasize to the duodenal papilla. We describe a case of primary lung cancer with duodenal papillary metastasis in a patient who presented with melena. To the best of our knowledge, this is only the second report of duodenal papillary metastasis from lung cancer. Case Presentation: A 65-year-old woman presented with complaints of anorexia, weight loss, and black stool. Imaging studies led to a clinical diagnosis of stage IVB lung cancer, and anticoagulants were initiated to treat pulmonary artery thrombosis. However, endoscopic hemostasis was challenging because of bleeding from a duodenal papillary tumor. Fortunately, the patient was positive for the plasma epidermal growth factor receptor (EGFR) gene mutation, and osimertinib, an EGFR tyrosine kinase inhibitor, was administered, successfully achieving hemostasis. Subsequently, endoscopic ultrasonography-guided transbronchial needle aspiration of an enlarged mediastinal lymph node and duodenal papillary tumor biopsy confirmed duodenal papillary metastasis of the primary lung adenocarcinoma. Conclusion: Although duodenal papillary metastasis is extremely rare, a good clinical outcome was achieved in this case by considering duodenal papillary metastasis from lung cancer as the differential diagnosis and administering systemic osimertinib therapy.

Safety and efficacy of atezolizumab plus bevacizumab combination therapy in patients with unresectable hepatocellular carcinoma undergoing dialysis: a case series.

Three patients aged 79, 75, and 81 years with unresectable hepatocellular carcinoma (HCC) and undergoing maintenance hemodialysis were treated with a combination of atezolizumab and bevacizumab. The patients, respectively, received their 22nd, 2nd, and 4th treatment cycles, and one achieved long-term stable disease. No serious adverse events, including immune-related adverse events, were observed in any patient. Remarkable progress has been made in chemotherapy for cancer; however, the efficacy and safety of chemotherapy in patients undergoing hemodialysis have not been adequately elucidated. This report provides novel insights into the feasibility and outcomes of atezolizumab and bevacizumab combination therapy in patients with HCC undergoing hemodialysis, highlighting its potential as a viable treatment option with manageable side effects.

Extranodal NK/T-cell lymphoma with localized relapse in bone marrow of lower leg detected using PET-CT.

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is a rare subtype of non-Hodgkin lymphoma (NHL) with poor prognosis, particularly in relapsed or refractory patients. Thus, timely detection of relapse and appropriate disease management are crucial. We present two patients with ENKTL, wherein positron emission tomography-computed tomography (PET-CT) with total-body coverage after induction therapy, detected newly relapsed regions in the bone marrow of the lower leg prior to progression. Case 1: A 47-year-old woman with nasal obstruction, showing 18F-fluoro-deoxyglucose (FDG) uptake in the nasal cavity (Lugano stage IE). After induction therapy (RT-2/3 DeVIC), PET-CT revealed abnormal uptake only in the right fibula. Case 2: A 68-year-old man with a skin nodule/ulcer and an enlarged right inguinal lymph node was diagnosed with advanced ENKTL. A PET-CT scan revealed abnormal uptake in the subcutaneous mass of the right medial thigh, lymph nodes, and descending colon (Lugano stage IV). After induction therapy, PET-CT revealed new abnormal uptake only in the left tibia. In both patients, CT-guided biopsy confirmed ENKTL recurrence. Moreover, PET-CT with whole-body coverage was useful for the timely assessment of relapse and detection of asymptomatic bone involvement. This approach allowed for modifications to treatment strategies in certain patients.

Prospective study on planned biliary stent placement to treat small common bile duct stones.

Aims: Small common bile duct stones are known to occasionally clear spontaneously. This study aimed to prospectively assess the role of biliary stent placement in promoting the spontaneous clearance of small common bile duct stones. Methods and Results: We analyzed patients presenting with common bile duct stones of ≤5 mm diameter between June 2020 and May 2022. The exclusion criteria included asymptomatic patients, biliary pancreatitis, altered gastrointestinal anatomy, bile duct strictures (malignant or benign), and a history of EST. The biliary stents were inserted without stone removal. Stone clearance was assessed using endoscopic ultrasonography or endoscopic retrograde cholangiopancreatography after 3 months. Our primary endpoint was the clearance rate of common bile duct stones over 6 months, targeting a lower limit for the 95% confidence interval (CI) exceeding 25%. Of the 32 enrolled patients, 18 (56.3%; 95% CI: 37.7-73.6%) exhibited stone clearance. Early complications occurred in 11 patients (34.4%), totaling 12 incidents: acute cholecystitis in four, acute pancreatitis in three, biliary pain in three, and cholangitis in two patients. No severe complications occurred. Six (18.8%) patients experienced asymptomatic stent migration. Following stone clearance, four (12.5%) patients experienced stone recurrence, with an average duration of 256 ± 164 days. Conclusion: Biliary stenting appeared to effectively promote the clearance of small common bile duct stones in approximately half of the patients. However, the potential complications and risks of stone recurrence warrant close monitoring.This trial was registered in the Japan Registry of Clinical Trials (jRCT1042200020).

[Successful portal vein stent placement for chronic portal vein stenosis 5 years after pancreatoduodenectomy:a case report].

A 73-year-old man underwent pancreatoduodenectomy 5 years previously, and portal vein stenosis was observed immediately after surgery. A collateral vein with varices around the hepaticojejunostomy gradually developed. The patient experienced repeated episodes of melena that required transfusion. Enteroscopy confirmed varices around the hepaticojejunostomy, caused by portal vein stenosis, which was the source of intestinal bleeding. Varices were treated by placing an expandable metallic stent in the stenotic portal vein through a percutaneous transhepatic route. Although the portal vein stenosis was severe, the guidewire was successfully maneuvered into the superior mesenteric vein and stent placement was successful. Subsequently, the collateral vein disappeared and no further melena was observed.

Comparison of Diagnostic Yield and Safety of Serial Pancreatic Juice Aspiration Cytologic Examination (SPACE) with Different Indications.

We assessed whether there are differences in the diagnostic yield and safety of serial pancreatic juice aspiration cytologic examination (SPACE) among different indications. We retrospectively analyzed 226 patients who underwent SPACE. They were classified into group A (patients with pancreatic masses, including advanced adenocarcinoma, sclerosing pancreatitis, or autoimmune pancreatitis), group B (suspicious pancreatic carcinoma patients without obvious pancreatic masses, including small pancreatic carcinoma, carcinoma in situ, or benign pancreatic duct stenosis), and group C (intraductal papillary mucinous neoplasm, IPMN). There were 41, 66, and 119 patients, with malignancy diagnosed in 29, 14, and 22 patients, in groups A, B, and C, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 69%, 100%, 100%, 57%, and 78% in group A; 79%, 98%, 92%, 94%, and 94% in group B; and 27%, 87%, 32%, 84%, and 76% in group C, respectively. PEP was observed in three (7.3%), three (4.5%), and fifteen (13%) patients in group A, B, and C, respectively (p = 0.20). SPACE is useful and safe in patients with suspicious small pancreatic carcinoma. However, it has limited efficacy and might not be recommended in patients with IPMN because of the high frequency of PEP.

Extracorporeal shock wave lithotripsy and endoscopic pancreatic stenting without pancreatic sphincterotomy for the treatment of pancreatolithiasis: a case series.

Endoscopic therapy and extracorporeal shock wave lithotripsy (ESWL) are recommended as the first choice in treating pancreatolithiasis. Endoscopic therapy is generally performed using endoscopic pancreatic sphincterotomy (EPST). Herein, we report our experience implementing a treatment protocol, combining endoscopic therapy and ESWL without EPST, for pancreatolithiasis. The inpatient treatment plan was performed every 3 months with a set number of sessions of ESWL with endoscopic pancreatic stenting (EPS) implanted or replaced. Finally, treatment was terminated when the stone was removed after implantation of a 10-Fr stent and crushed to approximately 3 mm or after spontaneous stone discharge. Eight patients were included in this study; the median time to stone disappearance was 208.5 days. The median number of inpatient treatment cycles, endoscopic retrograde cholangiopancreatography, and ESWL sessions was 2.5, 3, and 3, respectively. No serious adverse events were observed in all patients. Therefore, combining ESWL and EPS without EPST can safely treat pancreatolithiasis.

Intratumoral Air Bubbles and Hematemesis As Predictors of Pseudoaneurysm Rupture in Unresected Pancreatic Cancer.

Objective Pseudoaneurysm rupture associated with unresected pancreatic cancer can cause rare but fatal hemobilia and gastrointestinal bleeding. This study aimed to identify factors predicting pseudoaneurysm rupture. Methods We conducted a single-center case-control study of unresected pancreatic cancer patients treated at Shizuoka General Hospital between January 2011 and July 2020 using a retrospective cancer registry database. Included in the study were 611 consecutive patients with unresected pancreatic cancer, of whom 55 developed overt upper gastrointestinal bleeding or hemobilia. Twenty patients were excluded, as they had not undergone contrast-enhanced computed tomography (CT) or angiography. Patients were classified into pseudoaneurysm and non-pseudoaneurysm groups. One patient with arterial bleeding but without obvious pseudoaneurysm was included in the pseudoaneurysm group. Factors predicting pseudoaneurysm rupture at the onset of overt gastrointestinal bleeding were investigated using a logistic regression analysis. CT findings revealing air bubbles inside the tumor were described as intratumoral air bubbles. Results Thirty-five patients were included (15 in the pseudoaneurysm group, 20 in the non-pseudoaneurysm group). In the multivariate analysis, intratumoral air bubbles [odds ratio (OR), 12.9; 95% confidence interval (CI), 2.14-77.9; p=0.005] and hematemesis (OR, 6.30; 95% CI, 1.03-38.6; p=0.047) were independent predictors of pseudoaneurysm rupture. In addition, patients who experienced successful hemostasis and were re-administered chemotherapy survived more than six months. Conclusion This study reveals that intratumoral air bubbles and hematemesis may predict pseudoaneurysm rupture at the onset of overt gastrointestinal bleeding. For patients presenting these findings, an examination with conventional or CT angiography may lead to an early diagnosis and improve the patient prognosis.

Eosinophilic pancreatitis with serum IgG4-positivity, potentially associated with autoimmune pancreatitis.

A 70-year-old man presented with unprovoked weight loss and intermittent left upper quadrant tenderness for one-and-a-half month. Computed tomography revealed irregular cystic lesions in the pancreatic tail. Endoscopic ultrasonography (EUS) revealed pancreatic tail enlargement and giant, thick-walled cysts surrounding the pancreatic tail with no connection with the pancreatic duct. Endoscopic ultrasonography-guided fine-needle aspiration was performed on the enlarged pancreatic parenchyma and thickened cyst wall. Both biopsies showed hyper eosinophilia and few plasma cells. Endoscopic retrograde pancreatography revealed an irregular narrowing of the main pancreatic duct. Pancreatic juice cytology revealed substantial eosinophilia. Blood sampling showed an elevated eosinophil count and immunoglobulin G4 (IgG4) and immunoglobulin E (IgE) levels at the initial examination. We considered the patient to have eosinophilic pancreatitis (EP) with autoimmune pancreatitis, or alternately, EP with IgG4-related retroperitoneal fibrosis (RPF). Upon prednisolone administration, the abdominal pain improved, the peripheral blood eosinophil count decreased to zero, IgG4 and IgE levels decreased, pancreatic enlargement improved, and the cystic lesions disappeared. The condition did not recur within the following 3 years. Both EP and EP with IgG4-related RPF are rare etiologies of pancreatitis, and this case is very instructive.

An adult female case of autoimmune pancreatitis with gastric outlet obstruction complicated by annular pancreas.

A 65-year-old woman presented with epigastric pain persisting for more than 3 months. She was diagnosed with autoimmune pancreatitis (AIP), based on high serum IgG4 levels (981 mg/dL) and diffuse pancreatic enlargement with a capsule-like rim on computed tomography (CT). Additionally, the main pancreatic duct was indistinct on magnetic resonance cholangiopancreatography. CT, esophagogastroduodenoscopy, and upper gastrointestinal radiography revealed stenosis with gastric outlet obstruction (GOO) in the second part of the duodenum. Prednisolone administration was initiated as treatment; on day 3 of treatment, the patient's symptoms improved. After 2 weeks, CT and endoscopic ultrasonography of the duodenal bulbs revealed improvement of the enlarged pancreas. The second part of the duodenum ran into the pancreatic head, and no malignant lesions were observed. Based on the above findings, we suspect that she developed AIP in the annular pancreas (AnnP), where duodenal stenosis worsened with diffuse pancreatic enlargement, resulting in GOO. She is currently under careful observation with tapering of prednisolone-without surgical treatment for AnnP. The pathogenesis of GOO caused by AIP without malignancy is rare. One case of GOO caused by AIP, wherein AIP developed in the AnnP (similar to the present case), has been reported, highlighting the novelty of our report.

Beneficial impact of first-line mogamulizumab-containing chemotherapy in adult T-cell leukaemia-lymphoma.

Chemotherapy in combination with mogamulizumab (Mog) was approved in Japan in 2014 for untreated aggressive adult T-cell leukaemia-lymphoma (ATL), but the survival benefit remains unclear. Therefore, we retrospectively analysed clinical outcomes in 39 transplant-ineligible patients with untreated aggressive ATL at Kumamoto University Hospital between 2010 and 2021. The probability of four-year overall survival was 46.3% in the first-line Mog-containing treatment group compared to 20.6% in the chemotherapy-alone group (p = 0.033). Furthermore, this survival benefit was observed even in the elderly. In conclusion, first-line Mog-containing treatment can be a promising strategy for transplant-ineligible patients with ATL, especially in the elderly.

Diagnostic ability of pancreatic juice cytology via the minor papilla in patients with pancreas divisum.

Background and study aim: Endoscopic retrograde cholangiopancreatography (ERCP) is generally performed via the major papilla when evaluating patients with pancreatic disease. However, in patients with pancreas divisum (PD) or distortion of the main pancreatic duct, endoscopic retrograde pancreatography (ERP) should be performed via the minor papilla (MP). Our aim was to evaluate the efficacy and safety of endoscopic pancreatic juice cytology (PJC), performed via the MP, in patients with PD. Patients and methods: Patients with PD who underwent diagnostic ERP via the MP, between January 2010 and February 2021, were identified retrospectively from our hospital's ERCP database. Twenty-two patients contributing to 24 ERCPs were included in the analysis. Results: MP cannulation was successful in 23 of 24 ERCPs (96%). In one patient, successful cannulation was achieved on the second attempt and the procedure was performed twice in another. Serial pancreatic juice aspiration cytologic examination (SPACE) was performed in 17 patients, with a single aspiration of pancreatic juice performed in the other five. The sensitivity, specificity, and accuracy rates of ERCP diagnosis, overall, were 56%, 100%, and 80%, respectively. When diagnosis only based on SPACE was considered, the accuracy rate was even higher at 87%. Three patients (13%) developed mild pancreatitis as an adverse event. Conclusions: The diagnostic ability of endoscopic PJC, via the MP in patients with PD was technically feasible and relatively effective under experienced pancreatobiliary endoscopists, however, requiring careful attention to post-ERCP pancreatitis when performed.

Retrospective multicentre study on the effectiveness of first-line direct-acting antivirals against hepatitis C virus genotype-1.

WHAT IS KNOWN AND OBJECTIVE: In Japan, ledipasvir/sofosbuvir, elbasvir/grazoprevir and glecaprevir/pibrentasvir are recommended as first-line treatments for patients with untreated hepatitis C virus genotype 1. Although they have demonstrated a high efficacy in clinical trials, there are no direct comparative studies. Clarification of their effectiveness and safety in real-world clinical practice is required. Therefore, we conducted a retrospective multicentre study on the effectiveness of these direct-acting antivirals in real-world clinical practice. METHODS: We retrospectively evaluated the clinical data of untreated patients with persistent HCV genotype 1 infection who started first-line treatment with ledipasvir/sofosbuvir, elbasvir/grazoprevir or glecaprevir/pibrentasvir between September 2015 and January 2019 at 11 medical institutions in Japan. The primary efficacy endpoint was a sustained virologic response after 12 weeks of treatment. The secondary endpoints included sustained virologic response after 24 weeks of treatment and end of treatment response. The safety endpoint was treatment completion rate. RESULTS AND DISCUSSION: During the study, 420 patients (median age, 70 years; 181 males) received ledipasvir/sofosbuvir, 48 (median age 72, years; 29 males) received elbasvir/grazoprevir and 63 (median age 66, years; 35 males) received glecaprevir/pibrentasvir. For ledipasvir/sofosbuvir, elbasvir/grazoprevir and glecaprevir/pibrentasvir, the sustained virologic response after 12 weeks of treatment was 98.6%, 97.9% and 100%; the sustained virologic response after 24 weeks of treatment was 99.0%, 97.7% and 100%; the end of treatment response was 99.8%, 97.9% and 98.4%; and the treatment completion rate was 98.3%, 91.7% and 100% respectively. WHAT IS NEW AND CONCLUSION: In real-world clinical practice, hepatitis C virus treatment with ledipasvir/sofosbuvir, elbasvir/grazoprevir and glecaprevir/pibrentasvir was effective with safety.

Retrospective Analysis of Autologous Stem Cell Transplantation for AL Amyloidosis: A Study from the Multiple Myeloma Working Group of the Japan Society for Hematopoietic Cell Transplantation.

Autologous stem cell transplantation (ASCT) is the standard of care for eligible patients with light-chain (AL) amyloidosis, but little is known about it in Asian populations. To investigate the outcome of and prognostic factors for ASCT, we retrospectively analyzed ASCT cases registered to the Transplant Registry Unified Management Program between December 1999 and December 2015, with extra clinical information collected through a secondary survey. The primary endpoint was overall survival (OS). Hematologic response, organ response, and transplantation-related mortality were analyzed as secondary endpoints. The database search identified 330 patients (median age, 57 years; range, 31 to 74), and the secondary survey provided details for the 110 patients (33.3%) included in the study cohort. Fewer than 3 organs were involved in 56.4% of the patients, with cardiac involvement in 57.3%. Performance status (PS) was 0 to 1 in 83.6%. The conditioning melphalan dose was reduced in 54.6%. Overall hematologic response was a partial response or better in 77.6% of the patients and a complete response in 49.3%. The 5-year OS was 70.1%. A PS of 0 to 1 was associated with a significantly better prognosis in terms of OS. Although survival after ASCT for AL amyloidosis improved over time, poor PS and cardiac involvement had negative impacts on prognosis. The early mortality after ASCT was 6.4%. Poor PS and cardiac involvement led to high early mortality. A brain natriuretic peptide (BNP) level of 400 pg/mL was associated with worse OS. Our study has several limitations inherent to a retrospective analysis using a questionnaire. The depth of response and biomarker responses were significantly limited by the degree of missing data. Nonetheless, our data support the importance of careful patient selection for good outcomes of ASCT in patients with AL amyloidosis. In our cohort, poor PS and cardiac involvement had a negative impact on prognosis, and BNP level was a useful prognostic factor.

A case of primary nonleukemic myeloid sarcoma of the spleen, successfully treated by surgery and hematopoietic stem cell transplantation.

BACKGROUND: Myeloid sarcoma (MS) is a rare disease, mostly found in conjunction with acute myelogenous leukemia or other diseases, and primary nonleukemic MS of the spleen is particularly rare. CASE PRESENTATION: We report a 57-year-old male who presented with a spleen mass that was found incidentally, and was enlarged. As a result of various examinations, he was diagnosed with primary MS of the spleen with suspected involvement of the transverse colon, left kidney, pancreatic tail, and left diaphragm. He underwent a total splenectomy, partial pancreatectomy, partial colectomy, left nephrectomy, and left diaphragm partial resection. Histological examination revealed splenic primary MS. Bone marrow biopsy and immunophenotypic flow cytometry revealed no evidence of myeloid leukemia. He underwent umbilical cord blood transplantation, and he is currently living without a sign of recurrence at 10 months after surgery. CONCLUSIONS: We experienced a very rare case of primary spleen MS that was discovered without a hematologic malignancy. Two cases of surgically resected primary splenic MS have been reported, including the present case.

Successful endoscopic submucosal dissection of early gastric cancer located on gastric varices after treatment with balloon-occluded retrograde transvenous obliteration.

Gastric varices occur in patients with liver cirrhosis and cause major bleeding when they rupture. We report a case of an 80-year-old man with liver cirrhosis and chronic renal failure who was diagnosed with a gastric tumor located on gastric varices that had increased in size. The patient underwent balloon-occluded retrograde transvenous obliteration (BRTO) to control bleeding, and the gastric varices were eradicated. Two months after BRTO, endoscopic submucosal dissection (ESD) was performed, and en bloc resection was accomplished without severe intraoperative bleeding or complications during or after ESD. To our knowledge, this is the first report of successful treatment of early gastric cancer located on gastric varices by ESD in a patient with liver cirrhosis. Early gastric cancer located on gastric varices can be safely resected by performing BRTO prior to ESD.

[A case of poorly differentiated pancreatic adenocarcinoma with spontaneous regression wherein retrospective rim enhancement findings were important for diagnosis].

A 66-year-old man with epigastric pain was admitted to our hospital for further evaluation of a pancreatic mass, as indicated on transabdominal ultrasonography performed by his family doctor. Using various imaging modalities, the 22-mm tumor was diagnosed as a cystic tumor with hemorrhagic necrosis. The tumor diameter reduced to 11mm over the course of 1 month. However, the tumor margin was irregular than that at the initial diagnosis, and circumferential rim enhancement was observed in equilibrium phase computed tomography images. Therefore, we diagnosed the patient with pancreatic ductal adenocarcinoma with a necrotic component. Distal pancreatectomy with splenectomy was performed, and the subsequent histological diagnosis was poorly differentiated adenocarcinoma. This case had an interesting course as described by the diagnostic images.

Large Balloon Anchor Technique for Endoscopic Retrograde Cholangiopancreatography Required for Esophagogastroduodenal Deformities.

Objective It is difficult to insert a side-viewing duodenoscope during endoscopic retrograde cholangiopancreatography in patients with esophagogastroduodenal deformities. To evaluate the efficacy and safety of using a large balloon anchor technique for cases in which inserting side-viewing duodenoscopes is difficult. Methods We retrospectively examined patients with endoscopic retrograde cholangiopancreatography who required the large balloon anchor technique between April 2016 and October 2020. Patients with deformed superior duodenal angles, esophagogastric junctions and pyloric rings and those having a shortened lesser curve were included. Results The balloon as an anchor was safely used to insert the duodenoscopes in 17 patients, and this procedure was performed 21 times. The procedure was successful 20 out of 21 times (95.2%), including 12 cases with duodenal deformities, 5 with shortening of the lesser curve, 2 after duodenal stent placement and 1 with a deformity of the esophagogastric junction. In the remaining patient, the first ERCP was successful, but the second was unsuccessful with duodenal deformities. There were no complications throughout the course of the study. Conclusion The large balloon anchor technique is a safe and useful technique for patients when inserting side-viewing duodenoscopes is difficult for various reasons.

Hepatic Arterial Infusion Chemotherapy for Liver Metastases Following Standard Chemotherapy for Pancreatic Cancer.

A 65-year-old man diagnosed with locally advanced pancreatic cancer underwent distal pancreatectomy and combined portal vein resection. One month after surgery, contrast-enhanced magnetic resonance imaging revealed multiple liver metastases. We administered two courses of gemcitabine plus nab-paclitaxel combination therapy followed by 17 modified FOLFIRINOX courses. However, the response was insufficient, and the patient thereafter developed grade 3 neutropenia, which made it difficult to continue the treatment regimen. As a result, we administered hepatic arterial infusion chemotherapy comprising gemcitabine plus 5-fluorouracil because the residual tumor was limited to liver metastases. The progression-free survival period was 7 months, and no drug-related adverse effects were noted during the treatment.

A regulatory element in the 3'-untranslated region of CEBPA is associated with myeloid/NK/T-cell leukemia.

OBJECTIVES: CCAAT/enhancer-binding protein α (CEBPA) is an essential transcription factor for myeloid differentiation. Not only mutation of the CEBPA gene, but also promoter methylation, which results in silencing of CEBPA, contributes to the pathogenesis of acute myeloid leukemia (AML). We sought for another differentially methylated region (DMR) that associates with the CEBPA silencing and disease phenotype. METHODS: Using databases, we identified a conserved DMR in the CEBPA 3'-untranslated region (UTR). RESULTS: Methylation-specific PCR analysis of 231 AML cases showed that hypermethylation of the 3'-UTR was associated with AML that had a myeloid/NK/T-cell phenotype and downregulated CEBPA. Most of these cases were of an immature phenotype with CD7/CD56 positivity. These cases were significantly associated with lower hemoglobin levels than the others. Furthermore, we discovered that the CEBPA 3'-UTR DMR can enhance transcription from the CEBPA native promoter. In vitro experiments identified IKZF1-binding sites in the 3'-UTR that are responsible for this increased transcription of CEBPA. CONCLUSIONS: These results indicate that the CEBPA 3'-UTR DMR is a novel regulatory element of CEBPA related to myeloid/NK/T-cell lineage leukemogenesis. Transcriptional regulation of CEBPA by IKZF1 may provide a clue for understanding the fate determination of myeloid vs. NK/T-lymphoid progenitors.