Dacomitinib in EGFR-mutant non-small-cell lung cancer with brain metastasis: a single-arm, phase II study.

INTRODUCTION: Dacomitinib showed superior progression-free survival (PFS) and overall survival compared to gefitinib in patients with advanced non-small-cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations in the ARCHER1050 study. However, because that study did not include patients with brain metastases, the efficacy of dacomitinib in patients with brain metastases has not been clarified. PATIENTS AND METHODS: This single-arm phase II study enrolled 30 patients with treatment-naïve advanced NSCLC harboring activating EGFR mutations from January 2021 to June 2021 and started them on dacomitinib (45 mg/day). All patients had non-irradiated brain metastases with a diameter of ≥5 mm. The primary endpoint was confirmed intracranial objective response rate (iORR). RESULTS: Patients had exon 19 deletions (46.7%) and L858R mutations in exon 21 (55.3%). The confirmed iORR was 96.7% (29/30), with an intracranial complete response of 63.3%. Median intracranial PFS (iPFS) was not reached, with 12- and 18-month iPFS rates of 78.6% [95% confidence interval (CI) 64.8% to 95.4%] and 70.4% (95% CI 54.9% to 90.1%), respectively. In the competing risk analysis, the 12-month cumulative incidence of intracranial progression was 16.7%. Regarding the overall efficacy for intracranial and extracranial lesions, the overall ORR was 96.7%, and the median PFS was 17.5 months (95% CI 15.2 months-not reached). Grade 3 or higher treatment-related adverse events were reported in 16.7% of patients, and 83.3% required a reduced dacomitinib dose to manage adverse events. However, none permanently discontinued dacomitinib treatment due to treatment-related adverse events. CONCLUSIONS: Dacomitinib has outstanding intracranial efficacy in patients with EGFR-mutant NSCLC with brain metastases.

Validation study of machine-learning chest radiograph software in primary and emergency medicine.

AIM: To evaluate the performance of a machine learning based algorithm tool for chest radiographs (CXRs), applied to a consecutive cohort of historical clinical cases, in comparison to expert chest radiologists. MATERIALS AND METHODS: The study comprised 1,960 consecutive CXR from primary care referrals and the emergency department (992 and 968 cases respectively), obtained in 2015 at a UK hospital. Two chest radiologists, each with >20 years of experience independently read all studies in consensus to serve as a reference standard. A chest artificial intelligence (AI) algorithm, Lunit INSIGHT CXR, was run on the CXRs, and results were correlated with those by the expert readers. The area under the receiver operating characteristic curve (AUROC) was calculated for the normal and 10 common findings: atelectasis, fibrosis, calcification, consolidation, lung nodules, cardiomegaly, mediastinal widening, pleural effusion, pneumothorax, and pneumoperitoneum. RESULTS: The ground truth annotation identified 398 primary care and 578 emergency department datasets containing pathologies. The AI algorithm showed AUROC of 0.881-0.999 in the emergency department dataset and 0.881-0.998 in the primary care dataset. The AUROC for each of the findings between the primary care and emergency department datasets did not differ, except for pleural effusion (0.954 versus 0.988, p<0.001). CONCLUSIONS: The AI algorithm can accurately and consistently differentiate normal from major thoracic abnormalities in both acute and non-acute settings, and can serve as a triage tool.

Coagulopathy after snake envenomation in South Korea.

OBJECTIVE: This retrospective study investigated the nature and severity of venom-induced consumption coagulopathy (VICC) and determined the clotting factors involved in VICC in patients after envenomation by South Korea's snakes. Additionally, we studied the effectiveness of antivenom for the treatment of VICC after envenomation. METHODS: Included patients were divided into three groups according to the severity of VICC (no VICC, partial VICC, and complete VICC). Data, including changes in coagulation parameters during hospitalization and clotting factors at presentation, were collected and analyzed. RESULTS: One hundred nineteen patients who presented at our emergency department within 3 h after snake envenomation were included. VICC developed in 34 patients (27 patients with partial VICC and 7 patients with complete VICC). Two of 34 patients with VICC required blood transfusions. Five patients with complete VICC had an undetectable fibrinogen concentration at presentation. Three patients with complete VICC had an unmeasurable INR and aPTT within 24 h. The median times of the most extreme values were 10 h for INR, 12 h for aPTT, and 16 h for fibrinogen after presentation in the VICC group. The D-dimer concentration peaked at a median of 63.5 h after presentation. The activities of factors II and X were significantly reduced in the complete VICC group (factor II: 88 (84-99.3)% in the non-VICC group vs. 69 (49.5-83.5)% in the complete VICC group; factor X:94 (83-102) in the non-VICC group vs. 70 (66.5-79.8)% in the complete VICC group), while there was no difference in factor V activity at presentation. The time from bite to first antivenom administration did not correlate with the time course and most extreme concentrations for fibrinogen and D-dimer within the VICC groups. DISCUSSION AND CONCLUSION: VICC occurs in approximately one-quarter of snakebite patients in South Korea; however, VICC itself does not appear to lead to clinical deterioration. Fibrinogen is an early diagnostic maker for complete VICC. Clotting factors II and X are involved in VICC. Future investigations should explore the mechanism of VICC from Korean snakebites and the effect of antivenom on VICC.

A phase II, multicenter, two cohort study of 160 mg osimertinib in EGFR T790M-positive non-small-cell lung cancer patients with brain metastases or leptomeningeal disease who progressed on prior EGFR TKI therapy.

BACKGROUND: Up to 40% of patients with non-small-cell lung cancer (NSCLC) and epidermal growth factor receptor (EGFR) mutations treated with EGFR tyrosine kinase inhibitors (TKIs) present with disease progression in the central nervous system (CNS), either as brain metastases (BM) or leptomeningeal metastases (LM). Osimertinib (80 mg), a third-generation, irreversible, oral EGFR TKI, has shown efficacy in active CNS metastases. However, efficacy of osimertinib 160 mg in BM or LM is unclear. PATIENTS AND METHODS: This prospective, single-arm, two cohort study evaluated the efficacy of osimertinib 160 mg in T790M-positive BM or LM NSCLC patients who progressed on prior EGFR TKI (NCT03257124) treatment. The primary end points were objective response rate (ORR) (H1 = 30%) for the BM cohort and overall survival (OS) (H1 = 5 months) for the LM cohort. RESULTS: The median follow-up duration was 10.1 months and 9.6 months for the BM and LM cohorts, respectively. In the BM cohort, intracranial ORR and disease control rate were 55.0% and 77.5%, respectively. The median progression-free survival (PFS) was 7.6 months [95% confidence interval (CI) 5.0-16.6]; the median OS was 16.9 months [95% CI 7.9-not reached (NR)]. In the LM cohort, intracranial disease control rate was 92.5% and complete response rate was 12.5%. The median OS was 13.3 months (95% CI 9.1-NR); the median PFS was 8.0 months (95% CI 7.2-NR). Subgroup analyses based on previous exposure to T790M-targeting agents, including osimertinib 80 mg or other third-generation EGFR TKIs, showed no difference in PFS in both the BM (n = 18, P = 0.39) and LM (n = 17, P = 0.85) cohorts. Previous radiotherapy favored PFS in the BM cohort (hazard ratio 0.42, P = 0.04). The most common adverse events were decreased appetite, diarrhea, and skin rash; however, most were grade 1-2. CONCLUSION: Thus, osimertinib 160 mg demonstrated promising ORR and survival benefit with a tolerable safety profile in EGFR T790M-positive NSCLC patients with CNS metastasis who progressed on prior EGFR TKIs.

Updated overall survival and final progression-free survival data for patients with treatment-naive advanced ALK-positive non-small-cell lung cancer in the ALEX study.

BACKGROUND: The ALEX study demonstrated significantly improved progression-free survival (PFS) with alectinib versus crizotinib in treatment-naive ALK-positive non-small-cell lung cancer (NSCLC) at the primary data cut-off (9 February 2017). We report mature PFS (cut-off: 30 November 2018) and overall survival (OS) data up to 5 years (cut-off: 29 November 2019). PATIENTS AND METHODS: Patients with stage III/IV ALK-positive NSCLC were randomized to receive twice-daily alectinib 600 mg (n = 152) or crizotinib 250 mg (n = 151) until disease progression, toxicity, withdrawal or death. Primary end point: investigator-assessed PFS. Secondary end points included objective response rate, OS and safety. RESULTS: Mature PFS data showed significantly prolonged investigator-assessed PFS with alectinib [hazard ratio (HR) 0.43, 95% confidence interval (CI) 0.32-0.58; median PFS 34.8 versus 10.9 months crizotinib]. Median duration of OS follow-up: 48.2 months alectinib, 23.3 months crizotinib. OS data remain immature (37% of events). Median OS was not reached with alectinib versus 57.4 months with crizotinib (stratified HR 0.67, 95% CI 0.46-0.98). The 5-year OS rate was 62.5% (95% CI 54.3-70.8) with alectinib and 45.5% (95% CI 33.6-57.4) with crizotinib, with 34.9% and 8.6% of patients still on study treatment, respectively. The OS benefit of alectinib was seen in patients with central nervous system metastases at baseline [HR 0.58 (95% CI 0.34-1.00)] and those without [HR 0.76 (95% CI 0.45-1.26)]. Median treatment duration was longer with alectinib (28.1 versus 10.8 months), and no new safety signals were observed. CONCLUSIONS: Mature PFS data from ALEX confirmed significant improvement in PFS for alectinib over crizotinib in ALK-positive NSCLC. OS data remain immature, with a higher 5-year OS rate with alectinib versus crizotinib. This is the first global randomized study to show clinically meaningful improvement in OS for a next-generation tyrosine kinase inhibitor versus crizotinib in treatment-naive ALK-positive NSCLC. CLINICAL TRIALS NUMBER: NCT02075840.

HLA-corrected tumor mutation burden and homologous recombination deficiency for the prediction of response to PD-(L)1 blockade in advanced non-small-cell lung cancer patients.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have been shown to be beneficial for some patients with advanced non-small-cell lung cancer (NSCLC). However, the underlying mechanisms mediating the limited response to ICIs remain unclear. PATIENTS AND METHODS: We carried out whole-exome sequencing on 198 advanced NSCLC tumors that had been sampled before anti-programmed cell death 1 (anti-PD-1)/programmed death-ligand 1 (PD-L1) therapy. Detailed clinical characteristics were collected on these patients. We designed a new method to estimate human leukocyte antigen (HLA)-corrected tumor mutation burden (TMB), a modification which considers the loss of heterozygosity of HLA from conventional TMB. We carried out external validation of our findings utilizing 89 NSCLC samples and 110 melanoma samples from two independent cohorts of immunotherapy-treated patients. RESULTS: Homology-dependent recombination deficiency was identified in 37 patients (18.7%) and was associated with longer progression-free survival (PFS; P = 0.049). Using the HLA-corrected TMB, non-responders to ICIs were identified, despite having a high TMB (top 25%). Ten patients (21.3% of the high TMB group) were reclassified from the high TMB group into the low TMB group. The objective response rate (ORR), PFS, and overall survival (OS) were all lower in these patients compared with those of the high TMB group (ORR: 20% versus 59%, P = 0.0363; PFS: hazard ratio = 2.91, P = 0.007; OS: hazard ratio = 3.43, P = 0.004). Multivariate analyses showed that high HLA-corrected TMB was associated with a significant survival advantage (hazard ratio = 0.44, P = 0.015), whereas high conventional TMB was not associated with a survival advantage (hazard ratio = 0.63, P = 0.118). Applying this approach to the independent cohorts of 89 NSCLC patients and 110 melanoma patients, TMB-based survival prediction was significantly improved. CONCLUSION: HLA-corrected TMB can reconcile the observed disparity in relationships between TMB and ICI responses, and is of predictive and prognostic value for ICI therapies.

Role of thymoglobulin in matched sibling allogeneic hematopoietic stem cell transplantation with busulfan and fludarabine conditioning in myeloid malignanicies.

In vivo T-cell depletion using anti-thymocyte globulin (ATG) is widely used in allogeneic hematopoietic stem cell transplantation (HSCT) for prophylaxis of GvHD. We investigated the influence of thymoglobulin dose (an ATG) on GvHD following matched sibling donor (MSD) HSCT with a busulfan and fludarabine preparative regimen. Medical records of 180 patients who received MSD HSCT with a conditioning regimen of busulfan, fludarabine, and ATG (BuFluATG) were reviewed retrospectively. The median age was 53 years (range 18-68). Initial diagnoses were acute myeloid leukemia (73.3%) and myelodysplastic syndrome (26.7%). Forty-four and 68 patients (24.4 and 37.7%) experienced acute and chronic GvHD of any grade, respectively. High-dose (⩾4.5 mg/kg) ATG was independently associated with decreased risk of acute GvHD (hazard ratio=0.36, 95% confidence interval (CI): 0.15-0.84, P=0.019) compared to low-dose ATG (<4.5 mg/kg). Although ATG dose was associated with the risk of acute GvHD, it was not associated with the risk of chronic GvHD in our study. A higher dose (⩾4.5 mg/kg) of ATG decreases the risk of acute GvHD but had no significant impact on disease-free survival in MSD HSCT patients conditioned with BuFluATG. The optimal dose of ATG should be further investigated in a large prospective study context.

The clonal origins of leukemic progression of myelodysplasia.

The genetics behind the progression of myelodysplasia to secondary acute myeloid leukemia (sAML) is poorly understood. In this study, we profiled somatic mutations and their dynamics using next generation sequencing on serial samples from a total of 124 patients, consisting of a 31 patient discovery cohort and 93 patients from two validation cohorts. Whole-exome analysis on the discovery cohort revealed that 29 of 31 patients carry mutations related to at least one of eight commonly mutated pathways in AML. Mutations in genes related to DNA methylation and splicing machinery were found in T-cell samples, which expand at the initial diagnosis of the myelodysplasia, suggesting their importance as early disease events. On the other hand, somatic variants associated with signaling pathways arise or their allelic burdens expand significantly during progression. Our results indicate a strong association between mutations in activated signaling pathways and sAML progression. Overall, we demonstrate that distinct categories of genetic lesions play roles at different stages of sAML in a generally fixed order.

Non-alcoholic fatty liver diseases and risk of colorectal neoplasia.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is associated with colorectal neoplasia. Yet, NAFLD ranges from simple steatosis to steatohepatitis with advanced fibrosis. AIM: To investigate the risk of colorectal neoplasia according to the presence and severity of NAFLD. METHODS: A total of 26 540 asymptomatic adults who underwent same day first-time colonoscopy and abdominal ultrasonography as a health check-up programme were analysed. NAFLD was diagnosed by ultrasonography. Advanced colorectal neoplasia was defined as an invasive cancer or adenoma that was at least 10 mm in diameter, had high-grade dysplasia, or had villous histological characteristics or any combination thereof. RESULTS: NAFLD patients had a higher prevalence of any colorectal neoplasia (38.0% vs. 28.9%) and advanced colorectal neoplasia (2.8% vs. 1.9%) compared to those without NAFLD. In a multivariable model adjusted for age, sex, smoking, alcohol, body mass index, first-degree family history of colorectal cancer, aspirin use and metabolic factors, the odd ratios comparing patients with NAFLD to those without were 1.10 [95% confidence interval (CI): 1.03-1.17] for any colorectal neoplasia and 1.21 (95% CI: 0.99-1.47) for advanced colorectal neoplasia. When NAFLD patients were further stratified according to the non-invasive parameters of liver disease severity, the risk of any colorectal neoplasia or advanced colorectal neoplasia was higher for those with severe liver diseases than those with mild liver diseases. CONCLUSIONS: The presence and severity of NAFLD were closely associated with any colorectal neoplasia and advanced colorectal neoplasia, suggesting that clinicians should be aware of the increased risk of colorectal neoplasia in patients with NAFLD.

Vandetanib in pretreated patients with advanced non-small cell lung cancer-harboring RET rearrangement: a phase II clinical trial.

Background: Chromosomal rearrangements involving RET, which are found in about 1% of non-small cell lung cancer (NSCLC), define a unique molecular subset. We performed this study to examine the efficacy and safety of vandetanib 300 mg daily in this patient population. Patients and methods: This study was a multi-center, open-label, phase II clinical trial. Patients were enrolled if they had metastatic or recurrent NSCLC with a RET rearrangement, which was confirmed by fluorescence in situ hybridization, had progressive disease against platinum-based doublet chemotherapy, and had a performance status of 0-2. The primary endpoint was the objective response rate. Results: A total of 18 patients were enrolled in this study between July 2013 and October 2015. Patients were aged 35-71 years; three had a performance status of 2, and the majority were a heavily pretreated population (≥ two different previous chemotherapy regimens in 72% of the patients). Among the 17 evaluable patients, three had a partial response (objective response rate = 18%) and eight had a stable disease (disease control rate = 65%). Among these patients, the partial response or disease stabilization was durable for more than 6 months in eight patients. Vandetanib also showed a progression-free survival of 4.5 months, and an overall survival of 11.6 months during a median follow-up duration of 14 months. The safety profile was comparable with previous studies of vandetanib. Most vandetanib-related adverse events were mild with prevalent hypertension and rash (in >70% of patients). Grade 3 toxicity included hypertension (n = 3), QT prolongation (2), and elevation of aminotransferases (1), and as a consequence the dose was reduced in four patients. There were no adverse events associated with grade 4 or 5 toxicity. Conclusion: Vandetanib is moderately active in pretreated patients with advanced NSCLC-harboring RET rearrangements.

Minimal residual disease-based effect and long-term outcome of first-line dasatinib combined with chemotherapy for adult Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: The use of imatinib combined with chemotherapy has demonstrated improved outcome in adults with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL). However, a substantial proportion of patients continue to die as a result of disease progression. PATIENTS AND METHODS: We assessed the minimal residual disease (MRD)-based effect and long-term outcome of first-line incorporation of dasatinib (100 mg once daily) into chemotherapy alternatively for adults with Ph-positive ALL. The primary end point was the major molecular response (MMR) rate by the end of the second dasatinib cycle. Patients with a donor proceeded to allogeneic stem cell transplantation (SCT) as early as possible. MRD monitoring was centrally evaluated by real-time quantitative polymerase chain reaction (4.5-log sensitivity) using bone marrow samples. RESULTS: Fifty-one patients (median age, 46 years) were enrolled and treated with this strategy. After the first dasatinib cycle, 50 patients (98.0%) achieved complete remission (CR). By the end of the second dasatinib cycle, 46 (93.9%) of 49 assessable patients had persistent CR, and 38 (77.6%) had MMR (32.7%) or undetectable MRD (44.9%). On the basis of the MRD kinetics by this time point, the numbers of early-stable, late, and poor molecular responders were 23 (46.9%), 15 (30.7%), and 11 (22.4%), respectively. Thirty-nine patients (76.5%) underwent allogeneic SCT in CR1. After a median follow-up of 54 months, the 4-year cumulative incidence of relapse and disease-free survival (DFS) rate for all patients were 30.0% and 52.0%, respectively, and the corresponding outcomes among those receiving allogeneic SCT in CR1 were 20.5% and 64.1%, respectively. Poor molecular responders had a higher risk of relapse and DFS than those of early-stable molecular responders. CONCLUSION: This dasatinib-based protocol was effective for achieving a good quality molecular response and durable DFS in adults with Ph-positive ALL. TRIAL REGISTRATION: clinicaltrials.gov, NCT01004497.

Clonal dynamics in a single AML case tracked for 9 years reveals the complexity of leukemia progression.

Most types of cancers are made up of heterogeneous mixtures of genetically distinct subclones. In particular, acute myeloid leukemia (AML) has been shown to undergo substantial clonal evolution over the course of the disease. AML tends to harbor fewer mutations than solid tumors, making it challenging to infer clonal structure. Here, we present a 9-year, whole-exome sequencing study of a single case at 12 time points, from the initial diagnosis until a fourth relapse, including 6 remission samples in between. To the best of our knowledge, it covers the longest time span of any data set of its kind. We used these time series data to track the hierarchy and order of variant acquisition, and subsequently analyzed the evolution of somatic variants to infer clonal structure. From this, we postulate the development and extinction of subclones, as well as their anticorrelated expansion via varying drug responses. In particular, we show that new subclones started appearing after the first complete remission. The presence and absence of different subclones during remission and relapses implies differing drug responses among subclones. Our study shows that time series analysis contrasting remission and relapse periods provides a much more comprehensive view of clonal structure and evolution.

JAK2V617F mediates resistance to DNA damage-induced apoptosis by modulating FOXO3A localization and Bcl-xL deamidation.

The JAK2V617F mutation is found in most patients with a myeloproliferative neoplasm (MPN). This gain-of-function mutation dysregulates cytokine signaling and is associated with increased accumulation of DNA damage, a process likely to drive disease evolution. JAK2V617F inhibits NHE-1 upregulation in response to DNA damage and consequently represses Bcl-xL deamidation and apoptosis, thus giving rise to inappropriate cell survival. However, the mechanism whereby NHE-1 expression is inhibited by JAK2V617F is unknown. In this study, we demonstrate that the accumulation of reactive oxygen species (ROS) in cells expressing JAK2V617F compromises the NHE-1/Bcl-xL deamidation pathway by repressing NHE-1 upregulation in response to DNA damage. In JAK2V617F-positive cells, increased ROS levels results from aberrant PI3K signaling, which decreases nuclear localization of FOXO3A and decreases catalase expression. Furthermore, when compared with autologous control erythroblasts, clonally derived JAK2V617F-positive erythroblasts from MPN patients displayed increased ROS levels and reduced nuclear FOXO3A. However, in hematopoietic stem cells (HSCs), FOXO3A is largely localized within the nuclei despite the presence of JAK2V617F mutation, suggesting that JAK2-FOXO signaling has a different effect on progenitors compared with stem cells. Inactivation of FOXO proteins and elevation of intracellular ROS are characteristics common to many cancers, and hence these findings are likely to be of relevance beyond the MPN field.

Clinical and microbiological effects of a subantimicrobial dose of oral doxycycline on periodontitis in dogs.

Doxycycline is regarded as an effective treatment for periodontal inflammation. In humans, it has been shown that the long-term administration of a subantimicrobial dose of doxycycline (SDD) does not induce antimicrobial effects on the subgingival microflora and furthermore does not affect antimicrobial susceptibility. The present study was designed to evaluate the influence of oral administration of SDD on normal periodontal microflora and antimicrobial susceptibility in dogs. Experimental periodontitis was induced in 12 experimental dogs using a silk and wire-twisted ligature for 60 days. After the periodontitis induction period, the ligature was removed, and dental cleaning (subgingival and supragingival ultrasonic scaling) was performed. The dogs were randomly assigned to one of two groups: an SDD group with six dogs receiving 2 mg/kg PO once daily and a control group with six dogs receiving a placebo. At weeks 0, 4 and 8, clinical periodontal parameters were evaluated. After the clinical assessments, subgingival plaque was sampled and then cultured in an anaerobic system for one week, and the total anaerobes, Porphyromonas spp., Bacteroides spp. and Pasteurella spp. counts were investigated. Using the agar dilution method, the minimum bactericidal concentration of doxycycline was evaluated and the resistance for doxycycline was monitored during this experimental phase. The clinical periodontal status of the SDD group was significantly improved compared to the control group (P <0.05). Bacterial counts were not significantly different between the two experimental groups (P > 0.05), and antibacterial resistance was not established in the SDD group during the experimental periods (P <0.05). These results suggest that the once daily oral regimen of 2 mg/kg of doxycycline could serve as a SDD in dogs.

Bleaching Effects on Color, Chemical, and Mechanical Properties of White Spot Lesions.

OBJECTIVE: The purpose of the study was to evaluate the effect of bleaching on teeth with white spot lesions. METHODS AND MATERIALS: Carious lesions with standardized whiteness were produced on the buccal and lingual surfaces of human premolars by pH cycling. Specimens were subjected to four experimental conditions (n=20/group) as follows: group 1, control; group 2, caries formation followed by remineralization using fluoride-containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP; Tooth Mousse Plus, GC, Tokyo, Japan); group 3, caries formation followed by bleaching using 10% carbamide peroxide; and group 4, caries formation followed by both bleaching and remineralization. The CIE L(*)a(*)b(*) color values were measured with a spectroradiometer, the mineral content was measured with electron probe microanalysis (EPMA) on the cross-sectional surface of each specimen, and the Knoop hardness test was carried out along the EPMA scan line. Two-way analysis of variance was performed with Tukey post hoc comparison. RESULTS: The change in the CIE color values was not significantly different between the caries-formed (ΔE(*)=7.03) and the bleached enamel (ΔE(*)=7.60). Bleaching of the carious enamel extended the whiteness (ΔE(*)=3.38) without additional mineral loss (p<0.05). The remineralization treatment significantly increased the calcium (Ca), phosphate (P), and fluoride content of the subsurface lesion area (p<0.05). The cross-sectional microhardness values correlated well with the Ca and P content (R>0.80). CONCLUSIONS: Bleaching reduced the color disparities between sound and carious enamel without deteriorating the chemical and mechanical properties. The application of CPP-ACP paste enhanced mineral deposition in the subsurface lesion area of carious enamel.

Single monosomy as a relatively better survival factor in acute myeloid leukemia patients with monosomal karyotype.

Monosomal karyotype (MK) defined by either ⩾2 autosomal monosomies or single monosomy with at least one additional structural chromosomal abnormality is associated with a dismal prognosis in patients with acute myeloid leukemia (AML). It was detected in 174 of 3041 AML patients in South Korean Registry. A total of 119 patients who had received induction therapy were finally analyzed to evaluate the predictive factors for a positive prognosis. On multivariate analysis, single monosomy, the absence of abn(17p), ⩾10% of cells with normal metaphase and the achievement of a complete remission (CR) after induction therapy were significant factors for more favorable outcomes. Especially, single monosomy remained as a significantly independent prognostic factor for superior survival in both patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) in CR and who did not. Allo-HSCT in CR improved overall survival significantly only in patients with a single monosomy. Our results suggest that MK-AML may be biologically different according to the karyotypic subtype and that allo-HSCT in CR should be strongly recommended to patients with a single monosomy. For other patients, more prudent treatment strategies should be examined. Furthermore, the biological mechanism by which a single monosomy influences survival should be investigated.

A randomized phase III trial of stereotactic radiosurgery (SRS) versus observation for patients with asymptomatic cerebral oligo-metastases in non-small-cell lung cancer.

BACKGROUND: It is unclear whether treating brain metastasis before starting systemic chemotherapy can improve survival compared with upfront chemotherapy in non-small-cell lung cancer (NSCLC) with asymptomatic cerebral oligo-metastases. PATIENTS AND METHODS: We undertook a randomized, controlled trial of 105 patients with one to four brain metastases, admitted to Samsung Medical Center between 2008 and 2013. Patients were randomly assigned to receive stereotactic radiosurgery (SRS) (49 patients) followed by chemotherapy or upfront chemotherapy (49 patients). The primary end point was overall survival (OS) and secondary end points included central nervous system (CNS) progression-free survival, progression to symptomatic brain metastasis and brain functional outcome. RESULTS: The median age was 58 years (range, 29-85) with ECOG 0-1 performance status, and 40% of patients were never smokers. Most patients had adenocarcinoma, and about half of patients had only one brain metastasis, while the rest had multiple cerebral metastases. The median OS time was 14.6 months [95% confidence interval (CI), 9.2-20.0] in the SRS group and 15.3 months (95% CI, 7.2-23.4) for the upfront chemotherapy group (P = 0.418). There was no significant difference in time to CNS disease progression [median, 9.4 months (SRS) versus 6.6 months (upfront chemotherapy), P = 0.248]. Symptomatic progression of brain metastases was observed more frequently in the upfront chemotherapy group (26.5%) than the SRS group (18.4%) but without statistical significance. CONCLUSIONS: Although this study included smaller sample size than initially anticipated due to early termination, SRS followed by chemotherapy did not improve OS in oligo-brain metastases NSCLC patients compared with upfront chemotherapy. Further study with large number of patients should be needed to confirm the use of upfront chemotherapy alone in this subgroup of patients. CLINICAL TRIALS NUMBER: NCT01301560.

Small-cell lung cancer detection in never-smokers: clinical characteristics and multigene mutation profiling using targeted next-generation sequencing.

BACKGROUND: Once regarded as a smoker's disease, small-cell lung cancer (SCLC) has been occasionally detected in never-smokers as smoking rates decrease worldwide. We investigated the clinical and genetic characteristics of SCLC in never-smokers. PATIENTS AND METHODS: Patients diagnosed with SCLC were grouped into smokers and never-smokers. The clinical outcomes of the two groups were compared. For SCLC in never-smokers, somatic mutation profiling was carried out using the AmpliSeq™ Cancer Hotspot Panel v2 and semiconductor sequencing technology. Epidermal growth factor receptor (EGFR) mutation was confirmed by PNAClamp™. RESULTS: In total, 391 SCLC patients treated over a 5-year period were analyzed. Fifty patients (13%) were never-smokers. The median overall survival was 18.2 months in never-smokers and 13.1 months in smokers (P = 0.054). Never-smoking history was independently a good prognostic factor [hazard ratio = 0.645, 95% confidence interval (CI) 0.456-0.914], as were limited disease (HR = 0.372, 95% CI 0.294-0.471), and lower age (HR = 0.709, 95% CI 0.566-0.888). The objective response rates to first-line etoposide/cisplatin therapy were similar between never-smokers and smokers (75% versus 81%). Of 28 genetically evaluable never-smokers, EGFR mutations were detected in four cases (two L858R, one deletion in exon 19, and one G719A). Other mutations were in TP53 (n = 26), RB1 (n = 7), PTEN (n = 5), MET (n = 4), and SMAD4 (n = 3). CONCLUSIONS: Never-smokers with SCLC are increasingly prevalent and have a better prognosis than smokers with SCLC in Korea. Our study warrants further investigation in this group.