Yeung-Chul Mun

Pancreatic leak after left pancreatectomy is reduced following main pancreatic duct ligation

Although much is known about the long‐term outcome of patients undergoing left (distal) pancreatectomy for malignancy, comparatively little is known about the optimal management strategy for the residual transected pancreatic parenchyma and the divided pancreatic duct. Clinicopathological and operative factors that may contribute to postoperative pancreatic leak were evaluated.

Transepithelial Migration of Neutrophils in Response to Leukotriene B4 Is Mediated by a Reactive Oxygen Species-Extracellular Signal-Regulated Kinase-Linked Cascade

The epithelial cells that form a barrier lining the lung airway are key regulators of neutrophil trafficking into the airway lumen in a variety of lung inflammatory diseases. Although the lipid mediator leukotriene B4 (LTB4) is known to be a principal chemoattractant for recruiting neutrophils to inflamed sites across the airway epithelium, the precise signaling mechanism involved remains largely unknown. In the present study, therefore, we investigated the signaling pathway through which LTB4 induces transepithelial migration of neutrophils. We found that LTB4 induces concentration-dependent transmigration of DMSO-differentiated HL-60 neutrophils and human polymorphonuclear neutrophils across A549 human lung epithelium. This effect was mediated via specific LTB4 receptors and was inhibited by pretreating the cells with N-acetylcysteine (NAC), an oxygen free radical scavenger, with diphenylene iodonium (DPI), an inhibitor of NADPH oxidase-like flavoproteins, or with PD98059, an extracellular signal-regulated kinase (ERK) inhibitor. Consistent with those findings, LTB4-induced ERK phosphorylation was completely blocked by pretreating cells with NAC or DPI. Taken together, our observations suggest LTB4 signaling to transepithelial migration is mediated via generation of reactive oxygen species, which leads to downstream activation of ERK. The physiological relevance of this signaling pathway was demonstrated in BALB/c mice, in which intratracheal instillation of LTB4 led to acute recruitment of neutrophils into the airway across the lung epithelium. Notably, the response to LTB4 was blocked by NAC, DPI, PD98059, or CP105696, a specific LTB4 receptor antagonist.

Comparison of treatment strategies for patients with intestinal diffuse large B-cell lymphoma: Surgical resection followed by chemotherapy versus chemotherapy alone

The aim of this retrospective cohort study was to analyze the impact of surgery on the outcomes and qualities of life (QOL) in patients with intestinal diffuse large B-cell lymphoma (DLBCL). We assessed 345 patients with either localized or disseminated intestinal DLBCL and compared them according to treatment: surgical resection followed by chemotherapy versus chemotherapy alone. In patients with localized disease (Lugano stage I/II), surgery plus chemotherapy yielded a lower relapse rate (15.3%) than did chemotherapy alone (36.8%, P < .001). The 3-year overall survival rate was 91% in the surgery plus chemotherapy group and 62% in the chemotherapy-alone group (P < .001). The predominant pattern in the chemotherapy group was local relapse (27.6%). When rituximab was used with cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP), there was no improvement of the outcomes in patients treated with primary surgical resection. The QOL of patients who underwent surgery and chemotherapy was lower than chemotherapy alone, but its difference was acceptable. Multivariate analysis showed that surgical resection plus chemotherapy was an independent prognostic factor for overall survival. Surgical resection followed by chemotherapy might be an effective treatment strategy with acceptable QOL deterioration for localized intestinal DLBCL. This study was registered at www.clinicaltrials.gov as #NCT01043302.

Nilotinib combined with multiagent chemotherapy for newly diagnosed Philadelphia-positive acute lymphoblastic leukemia

We investigated the effects of nilotinib plus multiagent chemotherapy, followed by consolidation/maintenance or allogeneic hematopoietic cell transplantation (allo-HCT) for adult patients with newly diagnosed Philadelphia-positive (Ph-pos) acute lymphoblastic leukemia (ALL). Study subjects received induction treatment that comprised concurrent vincristine, daunorubicin, prednisolone, and nilotinib. After achieving complete hematologic remission (HCR), subjects received either 5 courses of consolidation, followed by 2-year maintenance with nilotinib, or allo-HCT. Minimal residual disease (MRD) was assessed at HCR, and every 3 months thereafter. The molecular responses (MRs) were defined as MR3 for BCR-ABL1/G6PDH ratios ≤10(-3) and MR5 for ratios <10(-5). Ninety evaluable subjects, ages 17 to 71 years, were enrolled in 17 centers. The HCR rate was 91%; 57 subjects received allo-HCT. The cumulative MR5 rate was 94%; the 2-year hematologic relapse-free survival (HRFS) rate was 72% for 82 subjects that achieved HCR, and the 2-year overall survival rate was 72%. Subjects that failed to achieve MR3 or MR5 were 9.1 times (P = .004) or 6.3 times (P = .001) more prone to hematologic relapse, respectively, than those that achieved MR3 or MR5. MRD statuses just before allo-HCT and at 3 months after allo-HCT were predictive of 2-year HRFS. Adverse events occurred mainly during induction, and most were reversible with dose reduction or transient interruption of nilotinib. The combination of nilotinib with high-dose cytotoxic drugs was feasible, and it effectively achieved high cumulative complete molecular remission and HRFS rates. The MRD status at early postremission time was predictive of the HRFS. This trial was registered at www.clinicaltrials.gov as #NCT00844298.

Prognostic Factors and Clinical Outcomes of High-Dose Chemotherapy followed by Autologous Stem Cell Transplantation in Patients with Peripheral T Cell Lymphoma, Unspecified: Complete Remission at Transplantation and the Prognostic Index of Peripheral T Cell Lymphoma Are the Major Factors Predictive of Outcome

High-dose chemotherapy followed by autologous stem cell transplantation (HDT/ASCT) offers a rescue option for T cell lymphoma patients with poor prognosis. However, the effectiveness of HDT/ASCT in patients with various peripheral T cell subtypes, optimal transplant timing, and the prognostic factors that predict better outcomes, have not been identified. We retrospectively investigated the clinical outcomes and prognostic factors for HDT/ASCT in 64 Korean patients with peripheral T cell lymphoma, unspecified (PTCL-U) between March 1995 and February 2007. The median age at transplantation was 44 years (range: 15-63 years). According to the age-adjusted International Prognostic Index (a-IPI) and the prognostic index of PTCL (PIT), 8 patients (12.5%) were in the high-risk group and 16 (26.6%) had the 2-3 PIT factors, respectively. After a median follow-up of 29.7 months, the 3-year overall survival (OS) and progression-free survival (PFS) rates were 53.0% +/- 7.5% and 44.3% +/- 7.0%, respectively. Univariate analysis showed that poor performance status, high lactate dehydrogenase (LDH) levels, high a-IPI score, high PIT classes, failure to achieve complete response (CR) at transplantation, and nonfrontline transplantation were associated with poor OS. Multivariate analysis showed that failure to achieve CR at transplantation (hazard ratio [HR] 2.23; 95% confidence interval [CI] 1.78-7.93) and 2-3 PIT factors (HR 3.76; 95% CI 1.02-5.42) were independent prognostic factors for OS. Failure to achieve CR at transplantation and high PIT are negative predictable factors for survival following HDT/ASCT in patients with PTCL-U.

Comparative analysis between azacitidine and decitabine for the treatment of myelodysplastic syndromes

The present study aimed to directly compare the efficacy and safety of azacitidine and decitabine in patients with myelodysplastic syndromes (MDS). We compared the overall response rate (ORR) (complete responses, partial responses, marrow complete responses, and haematological improvements), overall survival (OS), event‐free survival (EFS), time to leukaemic transformation, and adverse outcomes between azacitidine and decitabine. To minimize the effects of treatment selection bias in this observational study, adjustments were made using the propensity‐score matching method. Among 300 patients, 203 were treated with azacitidine and 97 with decitabine. Propensity‐score matching yielded 97 patient pairs. In the propensity‐matched cohort, there were no significant differences between the azacitidine and decitabine groups regarding ORR (44% vs. 52%), OS (26 vs. 22·9 months), EFS (7·7 vs. 7·0 months), and rate of leukaemic transformation (16% vs. 22% at 1 year). In patients ≥65 years of age, survival was significantly better in the azacitidine group (P = 0·017). Patients who received decitabine experienced more frequent episodes of grade 3 or 4 cytopenia and infectious episodes. We found that azacitidine and decitabine showed comparable efficacy. Among patients ≥65 years of age, survival was significantly better in the azacitidine group (ClinicalTrials.gov Identifier: NCT01409070).

Multicenter retrospective analysis of 581 patients with primary intestinal non-hodgkin lymphoma from the Consortium for Improving Survival of Lymphoma (CISL)

BackgroundPrimary intestinal non-Hodgkin lymphoma (NHL) is a heterogeneous disease with regard to anatomic and histologic distribution. Thus, analyses focusing on primary intestinal NHL with large number of patients are warranted.MethodsWe retrospectively analyzed 581 patients from 16 hospitals in Korea for primary intestinal NHL in this retrospective analysis. We compared clinical features and treatment outcomes according to the anatomic site of involvement and histologic subtypes.ResultsB-cell lymphoma (n = 504, 86.7%) was more frequent than T-cell lymphoma (n = 77, 13.3%). Diffuse large B-cell lymphoma (DLBCL) was the most common subtype (n = 386, 66.4%), and extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) was the second most common subtype (n = 61, 10.5%). B-cell lymphoma mainly presented as localized disease (Lugano stage I/II) while T-cell lymphomas involved multiple intestinal sites. Thus, T-cell lymphoma had more unfavourable characteristics such as advanced stage at diagnosis, and the 5-year overall survival (OS) rate was significantly lower than B-cell lymphoma (28% versus 71%, P < 0.001). B symptoms were relatively uncommon (20.7%), and bone marrow invasion was a rare event (7.4%). The ileocecal region was the most commonly involved site (39.8%), followed by the small (27.9%) and large intestines (21.5%). Patients underwent surgery showed better OS than patients did not (5-year OS rate 77% versus 57%, P < 0.001). However, this beneficial effect of surgery was only statistically significant in patients with B-cell lymphomas (P < 0.001) not in T-cell lymphomas (P = 0.460). The comparison of survival based on the anatomic site of involvement showed that ileocecal regions had a better 5-year overall survival rate (72%) than other sites in consistent with that ileocecal region had higher proportion of patients with DLBCL who underwent surgery. Age > 60 years, performance status ≥ 2, elevated serum lactate dehydrogenase, Lugano stage IV, presence of B symptoms, and T-cell phenotype were independent prognostic factors for survival.ConclusionsThe survival of patients with ileocecal region involvement was better than that of patients with involvement at other sites, which might be related to histologic distribution, the proportion of tumor stage, and need for surgical resection.

Acute Fibrinous and Organizing Pneumonia Following Hematopoietic Stem Cell Transplantation

A 60-year-old man presented with cough, sputum, and dyspnea. He had a history of acute myeloid leukemia and hematopoietic stem cell transplantation with chronic renal failure. Chest CT scans showed miliary nodules and patchy consolidations. Histological examination revealed numerous fibrin balls within the alveoli and thickening of the alveolar septum, both of which are typical pathological features of acute fibrinous and organizing pneumonia (AFOP). We report the first case of AFOP following allogeneic hematopoietic stem cell transplantation.

Early Imatinib Mesylate-Induced Hepatotoxicity in Chronic Myelogenous Leukaemia

Imatinib mesylate is the first molecule of targeted therapy in chronic myelogenous leukaemia inhibiting constitutively activated BCR-ABL kinase. There are no long-term follow-up studies of large sample sizes to assess the toxicity of the use of imatinib mesylate over 10 years. Several cases of hepatotoxicity, including fatal liver failure, have been associated with the long-term use of imatinib mesylate. We report here on a patient who experienced immediate dominant cholestatic damage of the liver and mild hepatocyte damage during imatinib mesylate therapy. This differs from most reports showing dominantly acute hepatitis with necrosis associated with the use of imatinib mesylate.

Imatinib withdrawal syndrome and longer duration of imatinib have a close association with a lower molecular relapse after treatment discontinuation: the KID study.

The aim of the Korean Imatinib Discontinuation Study was to identify predictors for safe and successful imatinib discontinuation. A total of 90 patients with a follow-up of ≥12 months were analyzed. After a median follow-up of 26.6 months after imatinib discontinuation, 37 patients lost the major molecular response. The probability of sustained major molecular response at 12 months and 24 months was 62.2% and 58.5%, respectively. All 37 patients who lost major molecular response were retreated with imatinib therapy for a median of 16.9 months, and all achieved major molecular response again at a median of 3.9 months after resuming imatinib therapy. We observed newly developed or worsened musculoskeletal pain and pruritus in 27 (30%) patients after imatinib discontinuation. Imatinib withdrawal syndrome was associated with a higher probability of sustained major molecular response (P=0.003) and showed a trend for a longer time to major molecular response loss (P=0.098). Positivity (defined as ≥ 17 positive chambers) of digital polymerase chain reaction at screening and longer imatinib duration before imatinib discontinuation were associated with a higher probability of sustained major molecular response. Our data demonstrated that the occurrence of imatinib withdrawal syndrome after imatinib discontinuation and longer duration of imatinib were associated with a lower rate of molecular relapse. In addition, minimal residual leukemia measured by digital polymerase chain reaction had a trend for a higher molecular relapse. (Trial registered at ClinicalTrials.gov: NCT01564836).