The plasma-soluble CSF1R level is a promising prognostic indicator for pediatric Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a rare hematologic neoplasm characterized by the clonal proliferation of Langerhans-like cells. Colony-stimulating factor 1 receptor (CSF1R) is a membrane-bound receptor that is highly expressed in LCH cells and tumor-associated macrophages. In this study, a soluble form of CSF1R protein (sCSF1R) was identified by plasma proteome profiling, and its role in evaluating LCH prognosis was explored. We prospectively measured plasma sCSF1R levels in 104 LCH patients and 10 healthy children using ELISA. Plasma sCSF1R levels were greater in LCH patients than in healthy controls (p < .001) and significantly differed among the three disease extents, with the highest level in MS RO+ LCH patients (p < .001). Accordingly, immunofluorescence showed the highest level of membrane-bound CSF1R in MS RO+ patients. Furthermore, the plasma sCSF1R concentration at diagnosis could efficiently predict the prognosis of LCH patients treated with standard first-line treatment (AUC = 0.782, p < .001). Notably, dynamic monitoring of sCSF1R levels could predict relapse early in patients receiving BRAF inhibitor treatment. In vitro drug sensitivity data showed that sCSF1R increased resistance to Ara-C in THP-1 cells expressing ectopic BRAF-V600E. Overall, the plasma sCSF1R level at diagnosis and during follow-up is of great clinical importance in pediatric LCH patients.

[L-DEP regimen salvage therapy for refractory primary hemophagocytic lymphohistiocytosis triggered by Epstein-Barr virus infection in 4 children]

Objective: To analyze the efficacy and safety of the L-DEP regimen (asparaginase, liposome doxorubicin, etoposide and methylprednisolone) as a salvage therapy for the refractory primary hemophagocytic lymphohistocytosis triggered by Epstein-Barr virus infection (EBV-pHLH) in children. Methods: In this retrospective case study, clinical and laboratory data before and after L-DEP regimen of 4 children diagnosed with EBV-pHLH in Beijing Children's hospital between January 2016 and June 2022 were collected, and the efficacy and safety of L-DEP regimen for the treatment of EBV-pHLH were analyzed. Results: Among 4 patients, there were 3 females and 1 male with the age ranged from 0.8 to 7.0 years. Two of them showed compound heterozygous mutations of PRF1, one with a heterozygous mutation of UNC13D, one homozygous mutation of ITK. Before the L-DEP therapy, all of them had anemia and a soaring level of soluble CD25, 3 patients had neutropenia and thrombopenia, 3 patients had a high level of ferritin, 3 patients had hypofibrinogenemia and 1 patient had hypertriglyceridemia. After receiving 1 or 2 cycles of L-DEP treatment, three achieved remission, including complete remission (1 case) and partial remission (2 cases), and the other one had no remission. The levels of blood cell counts, soluble CD25, triglyceride, fibrinogen and albumin were recovered gradually in 3 patients who got remission. All four patients underwent hematopoietic stem cell transplantation (HSCT) after L-DEP regimen, and three survived. All patients had no severe chemotherapy related complications. The main side effects were bone marrow suppression, infection and pancreatitis, which recovered after appropriate treatments, apart from one who died from severe infection after urgent HSCT. Conclusion: L-DEP regimen could be served as an effective and safe salvage treatment for refractory pediatric EBV-pHLH, and also provide an opportunity for patients to receive HSCT.

[Analysis of 9 cases of drug induced hypersensitivity syndrome related hemophagocytic lymphohistiocytosis]

Objective: To analyze the clinical features,treatment and prognosis of drug induced hypersensitivity syndrome related hemophagocytic lymphohistiocytosis (DIHS-HLH). Methods: This was a retrospective case study. Clinical characteristics, laboratory results, treatment and prognosis of 9 patients diagnosed with DIHS-HLH in Beijing Children's hospital between January 2020 and December 2022 were summarized. Kaplan-Meier survival analysis was used to calculate the overall survival rate. Results: Among all 9 cases, there were 6 males and 3 females, with the age ranged from 0.8 to 3.1 years. All patients had fever, rash, hepatomegaly and multiple lymph node enlargement. Other manifestations included splenomegaly (4 cases), pulmonary imaging abnormalities (6 cases), central nervous system symptoms (3 cases), and watery diarrhea (3 cases). Most patients showed high levels of soluble-CD25 (8 cases), hepatic dysfunction (7 cases) and hyperferritinemia (7 cases). Other laboratory abnormalities included hemophagocytosis in bone marrow (5 cases), hypofibrinogenemia (3 cases) and hypertriglyceridemia (2 cases). Ascending levels of interleukin (IL) 5, IL-8 and interferon-γ (IFN-γ) were detected in more than 6 patients. All patients received high dose intravenous immunoglobulin, corticosteroid and ruxolitinib, among which 4 patients were also treated with high dose methylprednisolone, 2 patients with etoposide and 2 patients with cyclosporin A. After following up for 0.2-38.6 months, 7 patients survived, and the 1-year overall survival rate was (78±14)%. Two patients who had no response to high dose immunoglobulin, methylprednisolone 2 mg/(kg·d) and ruxolitinib died. Watery diarrhea, increased levels of IL-5 and IL-8 and decreased IgM were more frequently in patients who did not survive. Conclusions: For children with fever, rash and a suspicious medication history, when complicated with hepatomegaly, impaired liver function and high levels of IL-5 and IL-8, DIHS-HLH should be considered. Once diagnosed with DIHS-HLH, suspicious drugs should be stopped immediately, and high dose intravenous immunoglobulin, corticosteroid and ruxolitinib could be used to control disease.

[Efficacy and safety of intermediate-dose cytarabine in the treatment of children with refractory high risk Langerhans cell histiocytosis]

Objective: To analyze the efficacy, safety, and long-term prognosis of intermediate-dose cytarabine (Ara-c) regimen in the treatment of children with refractory risk organ involvement Langerhans cell histiocytosis (LCH). Methods: Clinical data of 17 children with multisystem and risk organ involvement LCH who failed the first-line therapy and were treated with intermediate-dose Ara-c (250 mg/m2, twice daily) regimen in the Hematology Center, Beijing Children's Hospital from January 2013 to December 2016 were analyzed retrospectively. In addition to the basic treatment of vindesine and dexamethasone, the patients received two regimens: regimen A: the intermediate-dose Ara-c combined with cladribine and regimen B: the intermediate-dose Ara-c alone. The efficacy, safety and prognosis of the two regimens were analyzed. Results: Among all 17 patients, there were 11 males and 6 females, with the diagnosis age of 2.1 (1.6, 2.7) years. Ten children received regimen A, all of them achieved active disease-better (AD-B) after 8 courses of induction therapy. The disease activity scores (DAS) decreased from 5.5 (3.0, 9.0) to 1.0 (0, 2.3). Seven children received regimen B, and 6 of them achieved AD-B after 8 courses of induction therapy. The DAS decreased from 4.0 (2.0, 4.0) to 1.0 (0, 2.0). The follow-up time was 6.2 (4.9,7.2) and 5.2 (3.7,5.8) years in group A and B. The 5-year overall survival rate was 100.0% in both groups, and the 5-year event free survival rate was (88.9±10.5)% and (85.7±13.2)% in group A and B. Grade 3 or 4 myelosuppression was observed in 8 patients in group A and 2 patients in group B. Conclusions: The intermediate-dose Ara-c regimen (with or without cladribine) is effective and safe for patients with refractory high-risk LCH, with a good long-term prognosis.

Efficacy of ruxolitinib for HAVCR2 mutation-associated hemophagocytic lymphohistiocytosis and panniculitis manifestations in children

Frequent germline mutations of HAVCR2, recently identified in subcutaneous panniculitis-like T-cell lymphoma (SPTCL), are associated with an increased risk of hemophagocytic lymphohistiocytosis (HLH). However, SPTCL-HLH represents a challenge because of the difficulties in treatment with poor survival. Its malignant nature, specifically harbouring HAVCR2 mutations, has also been questioned. To better understand its pathology and treatment, we analysed the clinical data of six patients diagnosed at our centre. The median age at onset was 10.5 years (range, 0.8-12.4). Five patients presented with skin lesions of subcutaneous nodules/plaques and/or ulceration. All patients developed HLH; notably, one infant only had HLH without skin involvement. Histopathologically, only two patients were diagnosed with SPTCL and three were reported as panniculitis with no sufficient evidence of lymphoma. Genetically, germline homozygous mutation of HAVCR2 (p.Y82C) was identified in all patients, with a median diagnosis time of 4.6 months. All patients initially received corticosteroids, immunosuppressants or chemotherapy, achieving unfavourable responses. Strikingly, they responded well to ruxolitinib targeting inflammatory cytokines, allowing rapid disease resolution and/or long-term maintenance of remission. The excellent efficacy of ruxolitinib highlights this disease as an inflammatory condition instead of neoplastic nature and indicates novel agents targeting key inflammatory pathways as an encouraging approach for this disease entity.

Clinical outcomes and prognostic risk factors of Langerhans cell histiocytosis in children: Results from the BCH-LCH 2014 protocol study

Langerhans cell histiocytosis (LCH) is a rare myeloid neoplasm mainly affecting young children. This study aimed to evaluate the outcomes of 449 pediatric patients enrolled in the BCH-LCH 2014 study. 52.6% of patients were classified with single-system (SS) LCH, 28.1% with multisystem (MS) risk organ negative (RO-) LCH, and 19.4% with MS RO+ LCH. Three hundred ninety-six patients (88.2%) were initially treated with first-line therapy based on the vindesine-prednisone combination. One hundred thirty-nine patients who lacked a response to initial treatment were shifted to second-line therapy, 72 to intensive treatment Arm S1 (a combination of cytarabine, cladribine, vindesine, and dexamethasone), and 67 to Arm S2 (without cladribine). The 5-year overall survival (OS), progression-free survival (PFS), and relapse rates were 98.2% (median: 97.6 months), 54.6% (median: 58.3 months), and 29.9%, respectively. MS RO+ patients had the worst prognosis among the three clinical subtypes. For the patients initially treated with first-line therapy, the 5-year OS, PFS, and relapse rates were 99.2%, 54.5%, and 29.3%, respectively. Patients in Arm S1 had a significantly better prognosis than patients in Arm S2 (5-year PFS: 69.2% vs. 46.5%, p = .042; relapse rate: 23.4% vs. 44.2%, p = .031). Multivariate analysis revealed that early treatment response, the involvement of RO, skin, and oral mucosa, as well as laboratory parameters, including CRP and γ-GT, were independent risk factors for the PFS of LCH. Thus, the prognosis of LCH in children has been improved significantly with stratified chemotherapy, and progression and relapse remained the challenges, especially for RO+ patients.

[Interleukin-9 promotes the activation of hepatic stellate cells in mice infected with Schistosoma japonicum]

OBJECTIVE

To investigate the effects of interleukin-9 (IL-9) in the activation of hepatic stellate cells (HSCs) in mice infected with Schistosoma japonicum.

METHODS

Primary HSCs were isolated from mice 7 weeks post-infection with S. japonicum using the in situ liver perfusion and density gradient centrifugation, and cultured in vitro. HSCs were randomly assigned to the PBS control group and IL-9 stimulation group (stimulation with 20 ng/mL IL-9). HSCs were harvested 48 h and 72 h poststimulation, and the expression of α-smooth muscle actin (α-SMA), type I collagen (Col I) and type III collagen (Col III) was determined in HSCs using Western blotting.

RESULTS

Following stimulation with 20 ng/mL IL-9 for 48 h, the expression of α-SMA [(0.87 ± 0.02) vs. (0.69 ± 0.01); t = 17.39, P < 0.01], Col I [(0.74 ± 0.02) vs. (0.65 ± 0.01); t = 9.56, P < 0.01] and Col III [(0.94 ±0.04) vs. (0.75 ± 0.03); t = 6.15, P < 0.01] was significantly greater in HSCs in the IL-9 stimulation group than in the PBS control group. Following stimulation with 20 ng/mL IL-9 for 72 h, the expression of α-SMA was significantly greater in HSCs in the IL-9 stimulation group than in the PBS control group[(0.76 ± 0.02) vs. (0.58 ± 0.02); t = 12.52, P < 0.01]; however, there were no significant differences between the two groups in terms of Col I [(0.68 ± 0.02) vs. (0.66 ± 0.02); t = 1.15, P > 0.05] or Col III expression [(0.75 ± 0.01) vs. (0.72 ± 0.02); t = 2.22, P > 0.05].

CONCLUSIONS

IL-9 promotes the activation of HSCs in mice infected with S. japonicum.

[Efficacy and safety of modified hemophagocytic lymphohistiocytosis 04 regimen in Beijing Children's Hospital]

Objective: To evaluate the efficacy and safety of Beijing Children's Hospital (BCH) modified hemophagocytic lymphohistiocytosis (HLH) 04 regimen in the treatment of childhood HLH. Methods: A retrospective cohort study was conducted. From January 2016 to December 2017, 110 children with HLH who were treated with the modified HLH-04 regimen (replacing dexamethasone with methylprednisolone during the induction period, reducing the dose and frequency of etoposide, and not using cyclosporine except for autoimmune-related HLH) at the Hematology Oncology Center of Beijing Children's Hospital were selected as the modified group, while 102 children treated with the standard HLH-04 regimen from January 2012 to December 2015 were selected as the control group. The early remission rate, survival rate and adverse reactions of two groups were compared. Rank sum test and chi square test were used for comparison between groups. Results: The age of onset in the modified group was 1.9 (1.1, 3.5) years, with 65 males and 45 females. The age of onset in the control group was 2.0 (1.2, 4.6) years, with 47 males and 55 females. No significant difference was found in age and gender between 2 groups (both P>0.05). Except for fibrinogen (1.3 (1.0, 1.7) vs. 1.1 (0.8, 1.4) g/L, Z=-2.67, P=0.008) and natural killer cell activity (13.9 (13.4, 16.3) % vs.14.9 (12.0, 16.1) %, Z=-2.34, P=0.028), there were no statistically significant differences in etiology, disease duration, first clinical presentation, or laboratory tests between 2 groups (all P>0.05). At 2 months and 3 years, there were no statistically significant differences in overall survival between 2 groups (84.5% (93/110) vs.76.5% (78/102), 78.2% (86/110) vs. 67.6% (69/102), χ²=2.28, 3.07, P=0.131, 0.080). The first 3 weeks were the most common time for bone marrow suppression in the modified group, with a lower incidence than in the control group (47.3% (52/110) vs. 62.7% (64/102), χ²=5.11, P=0.024). The modified group had a lower rate of fungal infections than the control group (3.6% (4/110) vs. 13.7% (14/102), χ²=6.93, P=0.008). Compared with the control group, fewer children in the modified group died as a result of side effects from chemotherapy (8.0% (2/25) vs.30.3% (10/33), χ²=4.31, P=0.038). Conclusion: The BCH modified HLH-04 regimen reduced the intensity of chemotherapy, with overall efficacy no worse than the standard HLH-04 regimen, and significantly reduced the rate of chemotherapy-related myelosuppression, fungal infection and mortality.

[Ruxolitinib combined with liposomal doxorubicin, etoposide, methylprednisolone+/-PEG-asparaginase in treatment of relapsed/refractory pediatric hemophagocytic lymphohistiocytosis]

Objective: To investigate the efficacy and safety of ruxolitinib, liposomal doxorubicin, etoposide, methylprednisolone+/-PEG-asparaginase (RU-DEP+/-L) in the treatment of relapsed/refractory (R/R) pediatric hemophagocytic lymphohistiocytosis (HLH). Methods: The clinical data of R/R pediatric HLH, who accepted the RU-DEP+/-L regimen at Beijing Children's Hospital from January 2018 to December 2019 was retrospectively analyzed. Results: A total of 16 patients were included in this study, including 13 males and 3 females, aged[M(Q₁,Q₃)] 1 (1, 2) years at diagnosis. Thirteen patients were diagnosed with Epstein-Barr virus (EBV)-HLH, 2 with EBV-induced primary HLH, and 1 with unclear etiology, among which 3 patients were co-infected with CMV. After the first-line treatment, 11 patients had no response, and 5 patients relapsed after complete response. Nine patients received the RU-L-DEP regimen, and 7 patients received the RU-DEP regimen. The overall response rate and complete response of RU-DEP+/-L treatment were 10/16 and 3/16, respectively. The negative conversion rate of plasma EBV-DNA was 7/15. The median follow-up time was 35.1 (2.4, 40.7) months, and 9/16 patients were survival. The 3-year overall survival rate after RU-DEP+/-L treatment in response and accepted hematopoietic stem cell transplantation (HSCT) was higher than that without response and did not receive HSCT (P=0.048). Among the 16 patients, 9 had varying degrees of myelosuppression, and 13 had an infection. Conclusions: RU-DEP+/-L can be used as a salvage treatment in R/R pediatric HLH, which can provide a bridge to HSCT and play an important role in the control of HLH. The main adverse reactions are myelosuppression and infection, which can be tolerated.

Development and application of an LC-MS/MS method for pharmacokinetic study of ruxolitinib in children with hemophagocytic lymphohistiocytosis

Ruxolitinib (RUX), a small molecule inhibitor of JAK1/JAK2, has been identified as the possible novel targeted agent for the treatment of hemophagocytic lymphohistiocytosis (HLH). However, due to the lack of randomized clinical trials (RCTs), it is extremely difficult to determine the effective therapeutic dose for RUX in HLH patients, especially in pediatric patients. At the same time, the clinical response of pediatric patients to RUX varies greatly among individuals according to several case reports. Therefore, it is imperative to investigate the pharmacokinetic and pharmacodynamic characteristics of RUX in HLH children, and this must be based on a satisfactory method to determine the concentration of RUX. Owing to several limits of published analytical methods, herein, we describe a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) method for monitoring RUX in children's plasma samples. The protein precipitation method using methanol was used for sample cleanup. The analytes were separated by gradient elution in which 2.0 mM ammonium acetate in distilled water and acetonitrile were used as mobile phases. In the positive electrospray ionization (ESI+) mode, the m/z 307.1 → 186.0 and 316.1 → 185.9 ion pair transitions of RUX and RUX-d9 were used for the qualitative and quantitative analysis, respectively. The calibration curves of RUX were linear in the concentration range from 0.5 to 400 ng mL^-1. The intra- and inter-batch precision, accuracy, recovery, dilution completeness, and stability of this method were all within acceptable standards, and no matrix effects or residues were found. This method was successfully applied to the clinical pharmacokinetic study of RUX in 32 children with HLH. The pharmacokinetic parameters of HLH children after a single dose of RUX and the steady state plasma concentration after multiple administrations were proposed through this method. Most importantly, it was found that the age and serum creatinine (SCr) of children with HLH had a significant and complex impact on the in vivo process of RUX after the single as well as multiple administrations of RUX.

Characteristics and Treatment Outcomes of Pediatric Langerhans Cell Histiocytosis with Thymic Involvement

OBJECTIVE

To evaluate the characteristics and treatment outcomes of patients with pediatric Langerhans cell histiocytosis (LCH) with thymic involvement.

STUDY DESIGN

We retrospectively described the clinical, biological, and imaging characteristics of a series of 19 patients with pediatric LCH with thymic involvement in our center between September 2016 and December 2019. We further analyzed the treatment response and outcomes of patients treated with chemotherapy or targeted therapy.

RESULTS

Thymic involvement was found in 4.4% of a 433-consecutive pediatric LCH cohort; all LCH-thymic involvement presented with multisystem disease. Patients with thymic involvement were typically younger, harboring more lung and thyroid involvement and less bone involvement than those without thymic involvement. Most patients with thymic involvement had alteration of immunocompetence with decreased numbers of T-lymphocyte subsets and immunoglobulin G levels. Overall, 47.1% of patients demonstrated a response after 6 weeks of induction therapy, and 92.3% of the patients who did not respond to the first-line treatment had resolution of thymus after the second-line and/or targeted therapy. The progression/relapse rate showed no difference between patients who shifted to second-line therapy and those to dabrafenib (33.3% vs 25%, P = 1.000). The survival for patients with thymic involvement did not differ from those without thymic involvement. More patients treated with second-line chemotherapy had severe adverse events than those given dabrafenib (88.9% vs 0, P < .001).

CONCLUSIONS

Thymic involvement was observed rarely in LCH and had specific clinical characteristics. Chemotherapy could resolve most thymic lesions, and BRAF inhibitors might provide a promising treatment option with less toxicity for infants with BRAF-V600E mutation.

TRIAL REGISTRATION

http://www.chictr.org.cn, identifier: ChiCTR2000030457 (BCH-LCH 2014 study); ChiCTR2000032844 (dabrafenib study).

Clinical features and treatment outcomes of pediatric Langerhans cell histiocytosis with macrophage activation syndrome-hemophagocytic lymphohistiocytosis

Background

Langerhans cell histiocytosis (LCH) is a rare myeloid neoplasm. A few LCH patients had Macrophage activation syndrome-hemophagocytic lymphohistiocytosis (MAS-HLH), a life-threatening, hyper-inflammatory syndrome. We retrospectively described the clinical-biological characteristics of a series of 28 pediatric LCH patients with MAS-HLH in a single center. We further analyzed the difference in treatment outcomes between second-line chemotherapy (cytarabine and cladribine) and targeted therapy (dabrafenib) for BRAF-V600E-positive patients.

Results

LCH patients with MAS-HLH were aged < 2 years, harbored high frequencies of risk organ, skin, or lymph nodes involvement, and most of them carried BRAF-V600E mutation in lesions (88.0%) or plasma (90.5%). Patients were firstly treated with the initial induction first-line therapy (vindesine-steroid combination), and most of them (26/28) failed to control the active MAS-HLH after one six-week course of induction treatment. Then they were shifted to second-line chemotherapy or targeted therapy dabrafenib. BRAF-V600E-mutant patients treated with dabrafenib had prompt resolution of MAS-HLH signs and symptoms with less toxicity than second-line chemotherapy. Moreover, the progression-free survival (PFS) rate for patients given dabrafenib was much higher than those treated with chemotherapy (4 year-PFS: 75% vs. 14.6%, P = 0.034).

Conclusions

LCH patients with MAS-HLH harbored specific clinical-biology characteristics compared to the multisystem LCH without MAS-HLH. The BRAF inhibitor dabrafenib provides a promising treatment option for LCH with MAS-HLH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02276-y.

[Anaplastic lymphoma kinase-translocation renal cell carcinoma: clinical and pathological analysis]

Objective: To investigate the clinicopathological features, molecular characteristics, differential diagnosis and prognosis of anaplastic lymphoma kinase (ALK)-translocation renal cell carcinoma. Methods: Two cases of ALK-translocation renal cell carcinoma diagnosed from January 2011 to December 2020 were retrospectively analyzed to characterize their morphological features, immunohistochemical expression and prognosis. Multiple molecular studies including fluorescence in situ hybridization (FISH), reverse transcriptase-polymerase chain reaction (RT-PCR), and next-generation sequencing were performed to characterize the genetic alterations. Results: Two patients included one male and one female, with 59 and 57 years old, respectively. Morphologically, case 1 resembled collecting duct carcinoma or renal medullary carcinoma, which demonstrated tubular, microcapsule and reticular structures, with a remarkable myxoid background and lymphocytes infiltration; case 2 resembled Xp11.2 translocation renal cell carcinoma or type 2 papillary renal cell carcinoma, which demonstrated tubular papillary and focal solid structures, with flocculent cytoplasm and many foamy histiocytes, but without myxoid background and lymphocytes infiltration. Immunohistochemistry showed strongly positive expression of ALK. CK7, E-cadherin, vimentin, PAX8 and CD10 showed various degrees of expression, and other antibodies were nonreactive. A variety of molecular assays showed definite ALK gene translocation, with rare VCL-ALK gene fusion (VCL exon and 16-ALK exon 20) in case 1, and EML4-ALK gene fusion (EML4 exon and 2-ALK exon 20) in case 2. Conclusions: ALK-translocation renal cell carcinoma is rare with various morphological features, and is easy to miss and misdiagnose. The characteristic ALK expression and molecular detection of ALK translocation are helpful for diagnosing this type of renal cell carcinoma.

[Papillary renal neoplasm with reverse polarity: a clinicopathological analysis]

Objective: To study the clinical pathological characteristics, immunophenotype, molecular changes and prognosis of the papillary renal neoplasm with reverse polarity (PRNRP). Methods: Nine cases of PRNRP, diagnosed from 2013 to 2019, were retrieved from the Department of Pathology of Nanjing Jinling Hospital, Nanjing University School of Medicine. Histomorphology, immunophenotype and molecular genetics were analyzed with review of the literatures. Results: There were five male and four female patients, aged from 49 to 70 years, with an average age of 60.1 years. During a mean follow-up of 29 months, one patient died for other cause, and the others survived without disease. Microscopically, the tumor cells arranged in papillary structure with a fibrovascular core, the surface of which was covered with a single layer of cuboidal or columnar cells. The most prominent feature was that the tumor nuclei located at the top of the cytoplasm far from the basement membrane, and they were monotonous in size and arranged neatly with no or few nucleoli. Immunohistochemically, all nine cases of PRNRP showed diffuse positive expression of CK7 and E-cadherin, various degrees of P504s expression, and no expression of CD10 and CD117, with a Ki-67 index of 1%-3%. Unlike other papillary renal cell carcinoma, the nine cases of PRNRP all showed characteristic positive expression of GATA3. The fluorescence in situ hybridization assay showed that the majority of PRNRPs (8/9) did not have triploids on chromosomes 7 and 17. The sequencing of the KRAS gene confirmed the presence of a nonsense KRAS mutation in 8 of the 9 cases. Conclusions: PRNRP is a subtype of papillary renal cell carcinoma with characteristic morphological, immunophenotypic and molecular features, and indolent behaviors. More data are needed to define PRNRP as "carcinoma", and a definitive diagnosis of PRNRP is of great significance for proper treatment choice and accurate prognostication.

A pilot study of ruxolitinib as a front-line therapy for 12 children with secondary hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is an immune-regulatory disorder characterized by excessive production of inflammatory cytokines. The treatment recommendations of the HLH-1994 and HLH-2004 protocols have long been used in HLH therapy, but some patients still do not respond well to or have unacceptable side effects from conventional therapies. It is believed that cytokine-targeted strategies that directly target disease-driving pathways will be promising options for HLH. This prospective study aimed to investigate the efficacy and safety of ruxolitinib, a Janus kinase (JAK) 1/2 inhibitor, as a front-line therapy in children with secondary HLH. Twelve newly diagnosed patients without previous treatment were enrolled in this study with a median follow-up of 8.2 (7.1-12.0) months, including 8 cases of Epstein-Barr virus associated HLH (EBV-HLH), 2 cases of autoinflammatory disorder (AID)- associated HLH, and 2 cases of unknown etiology. Patients received oral ruxolitinib dosed on 2.5 mg, 5 mg or 10 mg twice daily depending on the body weight for 28 consecutive days. The overall response rate at the end of treatment (day 28) was 83.3% (10/12), with 66.7% (8/12) in complete response (CR), 8.3% (1/12) in partial response (PR), and 8.3% (1/12) in HLH improvement. Among the patients achieving CR, 87.5% (7/8) maintained CR condition for>6 months, and one patient with EBV-HLH relapsed following CR. For the EBV-HLH subgroup, all 8 patients responded to ruxolitinib, with a CR rate of 75% and a PR rate of 25%. Two patients with AID-associated HLH had quite different responses, with one showing reversal of the HLH abnormalities soon and the other showing no improvement, as did the two cases of unknown etiology. Patients who had no response or discontinued ruxolitinib all responded well to the subsequent HLH-1994 regimen. The expected 6-month event-free survival (EFS) rate was 58.3%±10.2%. No serious adverse effects were reported. Our study provides further support for the possibility of ruxolitinib targeted therapy for secondary HLH in children. This study was registered in the Chinese Clinical Trials Registry Platform (http://www.chictr.org.cn/) as ChiCTR2000029977.

Successful rescue of a lethal Griscelli syndrome type 2 presenting with neurological involvement and hemophagocytic lymphohistiocytosis: a case report

BACKGROUND

Griscelli syndrome type 2 (GS2) is a rare autosomal recessive disease caused by mutations in RAB27A gene. It is primarily characterized by a combination of partial albinism, hemophagocytic lymphohistiocytosis (HLH) or other immunodeficiency. However, neurological involvement at onset in GS2 and treatment has rarely been described.

CASE PRESENTATION

We describe a 3-year-old boy with GS2 in an Asian Chinese family. He presented with progressive neurological abnormalities following unremitting fever at onset. He developed HLH during the clinical course. A novel homozygous mutation (c.1 A > G) in RAB27A gene was subsequently identified. He was then treated by HLH-1994 protocol combined with ruxolitinib and experienced a dramatic remission. He subsequently underwent a successful haploidentical hematopoietic stem cell transplantation and stayed at a good condition.

CONCLUSIONS

We reported an atypical form of GS2 manifesting as severe central nervous system involvement at onset and subsequent HLH, which was successfully rescued in time. This case also highlights the need for early consideration of immunologic and genetic evaluation for HLH in unexplained neuroinflammation in the diagnostic work up.

BRAF V600E Mutation in Cell-Free DNA, Rather than in Lesion Tissues, at Diagnosis Is An Independent Prognostic Factor in Children with Langerhans Cell Histiocytosis

The aim of this study was to investigate the prognostic significance of BRAF^V600E in cell-free (cf) DNA (cfBRAF^V600E) and lesion tissues (ltBRAF^V600E) in pediatric Langerhans cell histiocytosis (LCH). This study included a total of 140 patients with successfully detected cfBRAF^V600E and ltBRAF^V600E at diagnosis. Treatment response at week 6 was correlated with both cfBRAF^V600E and ltBRAF^V600E Moreover, the patients with positive cfBRAF^V600E had a much lower 3-year progression-free survival (PFS) rate and a higher progression/reactivation rate than those with negative cfBRAF^V600E (47.1% ± 7.6% vs. 78.4% ± 5.1%, P < 0.0001; 44.6% vs. 19.0%, P = 0.001, respectively). However, no significant difference was found in the 3-year PFS rate or progression/reactivation rate between patients with positive and negative ltBRAF^V600E (P = 0.348 and 0.596, respectively). In addition, after patients were divided into group A (both cfBRAF^V600E and ltBRAF^V600E positive, n = 56), group B (ltBRAF^V600E positive and cfBRAF^V600E negative, n = 28), and group C (both cfBRAF^V600E and ltBRAF^V600E negative, n = 56), there was a significant difference in the 3-year PFS rate and progression/reactivation rate among the three groups (47.1% ± 7.6%, 92.9% ± 6.1%, and 72.2% ± 6.1%, P < 0.001; 44.6%, 3.6%, and 26.8%, P < 0.001, respectively). In the multivariate analysis, cfBRAF^V600E and age at diagnosis remained independent prognostic factors for 3-year PFS in childhood LCH. Therefore, cfBRAF^V600E was more closely associated with important clinical characteristics, treatment response at week 6, and prognosis than ltBRAF^V600E.

Associations between PRF1 Ala91Val polymorphism and risk of hemophagocytic lymphohistiocytosis: a meta-analysis based on 1366 subjects

BACKGROUND

Perforin (PRF1) gene mutation can cause the onset of hemophagocytic lymphohistiocytosis (HLH). It has reported that PRF1 Ala91Val polymorphism was related with HLH risk. In the meta-analysis, we aim to evaluate the association between PRF1 Ala91Val polymorphism and HLH risk.

METHODS

We accomplished a meta-analysis of six published case-control studies including 391 patients with HLH and 975 controls. We evaluated the quality of each study through Newcastle-Ottawa Scale (NOS). Data analysis was performed with Stata software.

RESULTS

In general, all studies were of high quality (NOS score higher than 7). There were statistically significant between the PRF1 Ala91Val polymorphism and HLH risk though the pooled analysis [for Ala/Val vs. Ala/Ala: pooled odds ratio (OR) = 3.22, 95% confidence interval (CI) 1.08-9.56, P = 0.035, random model; for Ala/Val + Val/Val vs. Ala/Ala: pooled OR = 2.96, 95% CI 1.14-7.69, P = 0.025, random model]. Furthermore, sensitivity analysis also revealed a relationship between PRF1 Ala91Val polymorphism and HLH risk (for Ala/Val vs. Ala/Ala: pooled OR = 5.236, 95% CI 2.72-10.08, P < 0.000, I² = 12.1%, P_{heterogeneity} = 0.332; for Ala/Val + Val/Val vs. Ala/Ala, pooled OR = 4.856, 95% CI 2.66-8.85, P < 0.000, I² = 5.9%, P_{heterogeneity} = 0.373). Funnel plot and Egger's test did not indicate obvious published bias (P = 0.841 for Ala/Val vs. Ala/Ala; P = 0.284 for Ala/Val + Val/Val vs. Ala/Ala).

CONCLUSION

This meta-analysis indicated that PRF1 Ala91Val polymorphism affects the factor for developing HLH and future studies of PRF1 Ala91Val on the onset of HLH will be guaranteed.

Effectiveness and Safety of Dabrafenib in the Treatment of 20 Chinese Children with BRAFV600E-Mutated Langerhans Cell Histiocytosis

Purpose

We sought to investigate the effectiveness and safety of dabrafenib in children with BRAF^V600E-mutated Langerhans cell histiocytosis (LCH).

Materials and Methods

A retrospective analysis was performed on 20 children with BRAF^V600E-mutated LCH who were treated with dabrafenib.

Results

The median age at which the patients started taking dabrafenib was 2.3 years old (range, 0.6 to 6.5 years). The ratio of boys to girls was 2.3:1. The median follow-up time was 30.8 months (range, 18.9 to 43.6 months). There were 14 patients (70%) in the risk organ (RO)⁺ group and six patients (30%) in the RO⁻ group. All patients were initially treated with traditional chemotherapy and then shifted to targeted therapy due to poor control of LCH or intolerance to chemotherapy. The overall objective response rate and the overall disease control rate were 65% and 75%, respectively. During treatment, circulating levels of cell-free BRAF^V600E (cfBRAF^V600E) became negative in 60% of the patients within a median period of 3.0 months (range, 1.0 to 9.0 months). Grade 2 or 3 adverse effects occurred in five patients.

Conclusion

Some children with BRAF^V600E-mutated LCH may benefit from monotherapy with dabrafenib, especially high-risk patients with concomitant hemophagocytic lymphohistiocytosis and intolerance to chemotherapy. The safety of dabrafenib is notable. A prospective study with a larger sample size is required to determine the optimal dosage and treatment duration.

Haploidentical Hematopoietic Stem Cell Transplantation for XIAP Deficiency: a Single-Center Report

PURPOSE

X-linked inhibitor of apoptosis (XIAP) deficiency caused by mutations in the XIAP/BIRC4 gene is a rare inherited primary immunodeficiency also known as X-linked lymphoproliferative syndrome type 2 (XLP2). Hematopoietic stem cell transplantation (HSCT) is currently the only curative strategy available. However, few studies of haploidentical HSCT have been published regarding the outcomes in patients with this syndrome.

METHODS

We evaluated the XIAP gene analysis and clinical characteristics of four Chinese patients with XIAP who underwent haploidentical HSCT.

RESULTS

The mutations in the two of four patients had not yet been reported in the literature. All of the patients had recurrent hemophagocytic lymphohistiocytosis but did not have a good matched donor and underwent haploidentical HSCT at BCH in China between September 2016 and December 2018. All four patients received antithymocyte globulin with fludarabine-based regimens. Two patients underwent reduced intensity conditioning (RIC), and the other two received modified myeloablative conditioning (MAC) regimens. Three of the four patients survived. Three patients experienced complications with mixed chimerism. One of the four patients who underwent RIC had early graft loss and then developed grade IV acute graft-versus-host disease (GVHD) after donor lymphocyte infusion with bone marrow. The two patients who received MAC survived with no or mild GVHD, even though one of them developed hepatic veno-occlusive disease in the early stage of transplantation.

CONCLUSIONS

Haploidentical HSCT may be a treatment option for patients with XIAP deficiency who lack a good matched donor. More studies are needed to determine whether modified MAC with reduced toxicity is more suitable for haploidentical transplantation.

[Analysis of five cases of hepatitis associated aplastic anemia presenting with hemophagocytic lymphohistiocytosis at onset]

Objective: To discuss the clinical characteristics and management approaches to hepatitis associated aplastic anemia (HAAA) presenting as hemophagocytic lymphohistiocytosis (HLH) at onset. Methods: The clinical data and laboratory results of hospitalized 5 HAAA patients presenting as HLH at onset in Beijing Children's Hospital from January 2017 to May 2019 were analyzed retrospectively. Results: Among 5 cases, there were 4 males and 1 female. The age of onset was 6.0 (2.7-12.7) years. All patients presented with high fever, hepatomegaly, hepatic dysfunction (aspartate aminotransferase 1 716 (1 409-2 570) U/L, alanine aminotransferase 1 699 (937-2 540) U/L) at onset. After admission, the laboratory results showed pancytopenia (white blood cell 1.2 (0.6-6.7) ×10(9)/L, haemoglobin 94 (65-111) g/L, blood platelet 29 (10-41) ×10(9)/L), decreased fibrinogen (1.3 (1.1-2.5) g/L), significantly elevated triglyceride (4.0 (2.8-5.1) mmol/L), ferritin (1 766 (399-5 253) μg/L) and soluble CD25 (27 457 (9 625-44 000) ng/L). Hemophagocytosis was found in the bone marrow smears of all 5 patients. The diagnosis of acute hepatitis and HLH was confirmed. During the treatment of HLH, the blood cells remain below normal level and the further biopsy of bone marrow (iliac bone) indicated low myeloproliferation. After exclusion of congenital bone marrow failure syndromes and other pancytopenic diseases, HAAA was confirmed. After the diagnosis of HAAA, 1 patient received antithymocyte globulin (ATG) and cyclosporin treatment in our hospital, 1 patient received allogeneic stem cell transplantation (HSCT) in other hospital, 2 patients received ATG in other hospitals. Only 1 patient died of severe infection. Conclusions: HAAA can present as HLH at onset. It is mainly manifested by high fever, acute severe hepatitis, pancytopenia, elevated ferritin and hemophagocytosis in the bone marrow. The diagnosis of HAAA should be considered whenever cytopenia could not completely corrected while apparent improvement of HLH and hepatitis related complications were improved after immunosuppressive therapy. ATG or HSCT treatment should be performed as soon as the diagnosis of severe or transfusion dependent aplastic anemia is confirmed.

[Expression of H3.3 G34W mutant-specific antibody in giant cell tumors of bone and its diagnostic value]

Objective: To investigate the expression of H3.3 G34W mutant-specific antibody in giant cell tumors of bone (GCTB), and its value in the diagnosis of GCTB. Methods: Immunohistochemical (IHC) EnVision method was used to detect the expression of H3.3 G34W mutant-specific antibody and p63 in 83 GCTBs, 18 aneurysmal bone cysts, 23 chondroblastomas and 28 osteosarcomas diagnosed at Nanjing Jinling Hospital from June 2001 to April 2019. Results: Among the 83 cases of GCTB, 69 cases (69/83, 83.1%) expressed H3.3 G34W. H3.3 G34W expression was found exclusively in the mononuclear cell population with strong and diffuse nuclear staining. H3.3 G34W was expressed in 55 of 57 (96.5%) cases of GCTB in long bones, but only 14 of 26 (53.8%) cases of non-long bone GCTB. All recurrent (9/9)/metastatic GCTB (2/2), post-denosumab GCTB (3/3), primary malignant GCTB (3/3) and secondary malignant GCTB (5/5) also expressed H3.3 G34W. H3.3 G34W was negative in all aneurysmal bone cysts and chondroblastomas. H3.3 G34W was positive in 3 of 28(10.7%) cases of osteosarcomas, and giant cell-rich osteosarcoma(GCRO) was the only histological subtype of osteosarcoma that expressed H3.3 G34W. p63 was expressed in 71.1%(59/83) of GCTB, while the positive rates of p63 in aneurysmal bone cysts,chondroblastomas and osteosarcomas were 3/18, 43.5% (10/23) and 21.4% (6/28) respectively. The sensitivity and specificity of H3.3 G34W mutant-specific antibody in the diagnosis of GCTB were 83.1% and 95.7%. Conclusions: H3.3 G34W mutant-specific antibody is a highly sensitive and specific marker for GCTB and helpful for the diagnosis of GCTB and its variants. The limitation of this antibody is that as a mall number of GCTB harbor G34 mutation other than G34W, and thus that cannot be detected. The incidental expression of H3.3 G34W mutant protein in osteosarcoma could be a potential diagnostic dilemma, and the results of H3.3 G34W IHC staining needs careful interpretation.

[Eosinophilic solid and cystic renal cell carcinoma: clinicopathological analysis and molecular characterization]

Objective: To study the clinicopathological features, immunohistochemical phenotype, molecular changes, differential diagnosis and prognosis of eosinophilic solid and cystic renal cell carcinoma (ESC RCC). Methods: A total of 15 cases were selected from 2005 to 2019 at Nanjing Jinling Hospital,Nanjing University School of Medicine for clinicopathological and immunohistochemical analysis, 10 of which were subject to cancer-associated mutation analysis using targeted next-generation sequencing (NGS) panel. A literature review was also performed. Results: The patients' ages ranged from 15 to 68 years (mean, 33 years). The male-to-female ratio was 1.1∶1.0. During a mean follow-up of 22 months, none of the patients developed tumor recurrence, progression or metastasis. Histologically, the tumors typically demonstrated solid and cystic architectures and the neoplastic cells contained voluminous eosinophilic cytoplasm with prominent granular cytoplasmic stippling. Immunohistochemically, tumor cells in all cases were immunoreactive for CK20. Signal pathway related protein mTOR and S6 were positive in 14/15 and 6/15 cases, respectively. Cathepsin K, Melan A and HMB45 were at least focally positive in 12/15, 6/15 and 2/15 cases, respectively. CK7 and CD10 showed focal immunostain positivity in some cases, while TFE3, TFEB, CA9 and CD117 were negative in all cases. NGS demonstrated TSC1/TSC2 mutations in all tested cases (10/10). Conclusions: ESC RCC is a rare tumor that tends to occur in young patients with an indolent behavior. Diagnosis can be established by its distinct clinical and histopathologic findings, immunohistochemical phenotype and molecular genetics. The tumor may be considered as a new subtype of RCC.

Significance of serum ferritin level in hemophagocytic lymphohistiocytosis diagnosis

INTRODUCTION

The threshold of serum ferritin (SF) level listed in diagnostic guidelines for hemophagocytic lymphohistiocytosis (HLH) of HLH-2004 has a low specificity. The goal of this research was to evaluate the role of admission SF in HLH diagnostic procedure and to find an appropriate threshold for a HLH suspected cohort with fever.

METHODS

All patients admitted to Beijing Children's Hospital during the period of September 1, 2015 and July 31, 2016 with fever and SF tested at admission were included in this study. The significance of SF in HLH diagnosis and its relationships with HLH-relevant clinical characteristics were studied.

RESULTS

Among 357 patients, 39 HLH cases were diagnosed (24 EBV-related HLH, 13 unknown etiologies triggered HLH, and two familial HLH). The best cutoff value of admission SF was 934 ng/mL, with sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) being 87.2%, 88.4%, 47.9%, and 98.3%, respectively. Compared to 500 ng/mL, specificity and PPV of the new SF standard in HLH diagnose increased by 11.7% and 14.0%, which indicated improvements in diagnostic ability of "non-HLH" and in veracity of "HLH" identification. Among four HLH patients whose admission SF was between 500 ng/mL and 934 ng/mL, HLH diagnosis was guaranteed by other laboratory results in two patients; however, possible misdiagnosis was made in the rest two patients.

CONCLUSION

Elevated cutoff value of admission SF level seems to be more appropriate for distinguishing HLH in patients with fever. The exact cutoff value of SF level at diagnosis needs to be determined.

Clinical Research of Pulmonary Langerhans Cell Histiocytosis in Children

Background:

Pulmonary Langerhans cell histiocytosis (PLCH) is an interstitial primary pulmonary disease, characterized by Langerhans cell proliferation. It is easily misdiagnosed in children. This study aimed to characterize the clinical manifestations and features of PLCH by retrospective analysis.

Methods:

A retrospective analysis was performed in 117 PLCH patients out of 338 LCH patients who were admitted in our center from November 2006 to October 2013. Variables between two groups were compared by Mann-Whitney U-test and Chi-square test. Kaplan-Meier curves were constructed to compare the survival rates and Cox regression to evaluate the effect of risk factors.

Results:

The median age of PLCH group was significantly lower than that of non-PLCH group (18.63 months vs. 43.4 months, P < 0.001). All PLCH children had other organ involvement and only 11 cases (9.4%) had respiratory symptoms. The most common radiologic finding was cystic lesions (29 cases, 24.8%). Pulmonary function abnormalities were dominated by obstructive ventilatory dysfunction (63 cases, 82.9%). The 5-year overall survival (OS) of PLCH children was 93.6% ± 2.3% and the event-free survival (EFS) was 55.7% ± 5.2%. Among the 38 cases with progressed or relapsed disease, five cases (13.2%) were due to progression or recurrence of lung damage. The 5-year OS of PLCH children with “risk organ” involvement was significantly lower than those without “risk organ” involvement (86.0% ± 4.9% vs. 100%, χ² = 8.793, P = 0.003). The difference of EFS between two groups was also significant (43.7% ± 7.7% vs. 66.3% ± 6.5%, χ² = 5.399, P = 0.020). The “risk organ” involvement had a significant impact on survival (hazard ratio = 1.9, P = 0.039).

Conclusions:

PLCH mainly occurs in young children, and only a small percentage of patients have respiratory symptoms. They generally have other organ involvement. Most of PLCH children have a good prognosis and most lung lesions could have improved or stabilized. Management of “risk organ” involvement is the key point to improving EFS.

Central Nervous System Involvement in 179 Chinese Children with Hemophagocytic Lymphohistiocytosis

Background:

Central nervous system (CNS) involvement is found in many patients with hemophagocytic lymphohistiocytosis (HLH). In this study, we mainly analyzed neurological symptoms, imaging findings, cerebrospinal fluid (CSF), and their relationship with outcomes of HLH children.

Methods:

Related data of 179 Chinese pediatric patients with HLH admitted to our center from January 2010 to December 2015 were analyzed retrospectively. Diagnosis and treatment were based on the HLH-2004 protocol. Two-tailed Chi-squared test was used to compare between different groups, and Kaplan-Meier survival curves were used to analyze the overall survival (OS) of patients with HLH.

Results:

In the present study, 21.2% (38/179) of total patients had neurological symptoms including seizure, irritability, somnolence, and unconsciousness. There were 80 (50.0%, excluding 19 patients without imaging data) patients with cranial imaging abnormalities. There were 14.7% (17/116, excluding 63 patients who did not accept lumbar puncture) of patients with abnormal CSF results. CNS involvement is defined as abnormalities in one or more of CNS symptoms, radiological findings, and CSF. Thus, 60.3% of them had CNS involvement. As for the prognosis, the median follow-up time was 3.2 years (17 lost to follow-up). The probable 3-year OS of children was higher without CNS involvement (86.0% ± 4.6%) than those with CNS involvement (68.9% ± 4.9%, hazard ratio [HR] = 2.286, P = 0.019). Among them, the probable 3-year OS of children without CNS symptoms was 76.0% ± 3.8%, higher than with CNS symptoms (59.5% ± 8.1%, HR = 2.147, P = 0.047). The 3-year OS of children with abnormal CSF was 64.7% ± 11.6%, compared with normal CSF (85.1% ± 3.7%, HR = 0.255, P = 0.038).

Conclusions:

HLH patients with CNS involvement might have worse outcomes compared with those without CNS involvement, and CNS symptoms and CSF changes are more important to access the prognosis than imaging abnormality.

[Primary mediastinal large B-cell lymphoma: a clinicopathologic study of 27 cases]

Objective: To study the clinicopathologic characteristics and diagnostic criteria of primary mediastinal B-cell lymphoma (PMBL), and to distinguish PMBL from classic Hodgkin lymphoma(CHL) and systemic diffuse large B-cell lymphoma(DLBCL). Methods: The clinical features, histologic findings, results of immunohistochemical study and prgnosis in 27 PMBL cases were analyzed, with review of literature. Results: The age of patients ranged from 19 to 82 years (median age 34 years). All cases were located in the mediastinum and frequently accompanied by superior vein cava syndrome. Histologically, the tumor cells were pleomorphic and diffusely distributed. Clear cytoplasm and spindle tumor cells were seen in some cases. Varying amount of sclerosing stroma with collagen deposition was seen.Immunohistochemical study showed that the tumor cells were positive for CD20(100%, 27/27), CD30 (64.0%, 16/25), CD23 (77.3%, 17/22) and p63 (16/19). Clonal B cell gene rearrangement was seen. Conclusions: PMBL is a subtype of diffuse large B-cell lymphoma with various histomorphology. Immunohistochemistry can help to confirm the diagnosis, and the prognosis is better than diffuse large B cell lymphoma, not otherwise specified.

[Molecular features of metanephric adenoma and their values in differential diagnosis]

Objective: To study the molecular features of metanephric adenoma (MA) and discuss their values in differential diagnosis. Methods: BRAF V600E immunohistochemistry (IHC) using the mutation-specific VE1 monoclonal antibody and Sanger sequencing of BRAF mutations were performed on 21 MAs, 16 epithelial-predominant Wilms tumors (e-WT) and 20 the solid variant of papillary renal cell carcinomas (s-PRCC) respectively. p16 protein was detected by IHC also. Fluorescence in situ hybridization (FISH) analyses using centromeric probes for chromosome 7 and 17 were performed on the three renal tumors in parallel. Results: Fourteen (14/21, 66.7%) of 21 MA cases demonstrated diffuse, moderate to strong cytoplasmic BRAF V600E IHC staining and the BRAF V600E protein expression was detected in 2 (2/16) of 16 e-WT cases for the first time, whereas all s-PRCCs were negative (P<0.05). All cases (including 14 MAs and 2 e-WTs) with diffuse, moderate to strong cytoplasmic BRAF V600E IHC staining were confirmed to harbor BRAF V600E missense mutations using Sanger sequencing, and no BRAF mutations were detected in cases with negative BRAF V600E protein expression. One case (1/21, 4.8%) showed trisomy of chromosome 7 alone, and another one (1/21, 4.8%) showed trisomy of chromosome 17 alone in 21 MAs. Two cases (2/16) of 16 e-WTs showed trisomy of chromosome 17 alone. In 20 s-PRCCs, trisomy of chromosomes 7 alone was reported in 2 cases (2/20), trisomy of chromosome 17 alone in 3 cases (3/20) and trisomy of chromosome 7 and 17 in 14 cases (14/20). The total positive rates of trisomy of chromosome 7 and/or 17 in MAs, e-WTs and s-PRCCs were 9.6% (2/21), 2/16 and 95.0% (19/20). p16 protein was positive in 81.0% (17/21) MAs, whereas the positive rates in e-WTs and s-PRCCs were 2/16 and 5.0% (1/20). Conclusions: Most MAs harbor BRAF V600E mutations, and MAs lack the gains of chromosome 7 and 17 that are characteristic of papillary renal cell carcinoma. These molecular features can be used to distinguish MA from its mimics. BRAF V600E IHC using the mutation-specific VE1 monoclonal antibody provides an effective method in BRAF V600E mutations detection of renal tumors. p16 is overexpressed in MA, and the finding suggests that the low proliferative rate of the tumor might be attributed to BRAF V600E-induced senescence mediated by p16.

[Application of BRAF V600E mutation-specific immunohistochemistry in diagnosis of gastrointestinal stromal tumors]

OBJECTIVE

To evaluate the utility of BRAF V600E allele-specific antibody in the diagnosis of gastrointestinal stromal tumors (GISTs).

METHODS

BRAF V600E mutation-specific immunohistochemistry and BRAF sequencing were performed in 24 consecutive GISTs, including 14 cases of KIT or PDGFRA mutations and 10 cases of KIT/PDGFRA wild GISTs.

RESULTS

GISTs of 11 men and 13 women with a mean age 54 years(range 29-75 years) were included with tumors arising from stomach (16 cases), small bowel (7 cases), and peritoneal cavity (1 case). Strong and diffuse cytoplasmic BRAF staining was noted in 4 of 24 cases (17%), while 1 of 24 cases (4%) showed weak staining, and 19 of 24 cases (79%) had no staining. The four cases with strong BRAF immunostain were confirmed to have BRAF mutations, including 3 cases in the stomach and 1 case in the small intestine. All tumors showed spindle cell morphology. Only one case had progressive disease. No BRAF mutations were detected in cases with weak or negative BRAF immunostain.

CONCLUSION

BRAF V600E mutation-specific immunohistochemistry is a highly sensitive and specific marker for detecting BRAF-mutated GISTs.

[Expression of cadherin17 in metanephric adenoma and its value in differential diagnosis]

OBJECTIVE

To study the expression of cadherin17(CDH17) in metanephric adenoma (MA), and to explore the value of CDH17 in the diagnosis of metanephric adenoma.

METHODS

Immunohistochemical EnVision method was used to detect the expression of CDH17, WT1, CD57, P504S and EMA in 21 cases of MAs, 16 epithelial-predominant Wilms tumors (e-WT), and 20 solid variant of papillary renal cell carcinomas (s-PRCC). The expression of CDH17 was also examined in other common renal epithelial tumors, including 10 cases of clear cell renal cell carcinomas (CCRCC), 10 chromophobe renal cell carcinomas (CHRCC), and 10 oncocytomas.

RESULTS

Twenty (95.2%) of 21 cases of MAs demonstrated membranous CDH17 immunoreactivity in all components (acinar, tubular, and papillary), whereas only 1 (1/16) e-WT was positive for CDH17 and all s-PRCCs were negative (P<0.05). WT1 was negative in s-PRCC and was positive in all cases of e-WT (16/16) and MA (100%, 21/21). All MAs (100%) were strongly positive for CD57; however, this marker was also positive in 13 (13/16) e-WTs and 9 (45.0%, 9/20) s-PRCCs. P504S was strongly positive in all s-PRCCs (100%), but reactivity was seen in 3 (14.3%, 3/21) MAs and all e-WTs were negative. The positive rates of EMA in MAs, e-WTs and s-PRCCs were 19.0%(4/21), 14/16 and 17/20, respectively. The sensitivity and specificity of CDH17 in the diagnosis of MA were 95% and 97%. CDH17 was negative in all cases of CCRCC, CHRCC and oncocytoma.

CONCLUSIONS

CDH17 is a highly sensitive and specific marker for MA and should be considered in the immunohistochemistry panel for distinguishing MA from its mimics and other common renal epithelial tumors.

Renormalization group invariance and optimal QCD renormalization scale-setting: a key issues review

A valid prediction for a physical observable from quantum field theory should be independent of the choice of renormalization scheme--this is the primary requirement of renormalization group invariance (RGI). Satisfying scheme invariance is a challenging problem for perturbative QCD (pQCD), since a truncated perturbation series does not automatically satisfy the requirements of the renormalization group. In a previous review, we provided a general introduction to the various scale setting approaches suggested in the literature. As a step forward, in the present review, we present a discussion in depth of two well-established scale-setting methods based on RGI. One is the 'principle of maximum conformality' (PMC) in which the terms associated with the β-function are absorbed into the scale of the running coupling at each perturbative order; its predictions are scheme and scale independent at every finite order. The other approach is the 'principle of minimum sensitivity' (PMS), which is based on local RGI; the PMS approach determines the optimal renormalization scale by requiring the slope of the approximant of an observable to vanish. In this paper, we present a detailed comparison of the PMC and PMS procedures by analyzing two physical observables R(e+e-) and [Formula: see text] up to four-loop order in pQCD. At the four-loop level, the PMC and PMS predictions for both observables agree within small errors with those of conventional scale setting assuming a physically-motivated scale, and each prediction shows small scale dependences. However, the convergence of the pQCD series at high orders, behaves quite differently: the PMC displays the best pQCD convergence since it eliminates divergent renormalon terms; in contrast, the convergence of the PMS prediction is questionable, often even worse than the conventional prediction based on an arbitrary guess for the renormalization scale. PMC predictions also have the property that any residual dependence on the choice of initial scale is highly suppressed even for low-order predictions. Thus the PMC, based on the standard RGI, has a rigorous foundation; it eliminates an unnecessary systematic error for high precision pQCD predictions and can be widely applied to virtually all high-energy hadronic processes, including multi-scale problems.

Supercritical water oxidation of acrylic acid production wastewater

Supercritical water oxidation (SCWO) of wastewater from an acrylic acid manufacturing plant has been studied on a continuous flow experimental system, whose reactor was made of Hastelloy C-276. Experimental conditions included a reaction temperature (T) ranging from 673 to 773K, a residence time (t) ranging from 72.7 to 339s, a constant pressure (P) of 25 MPa and a fixed oxidation coefficient (alpha) of 2.0. Experimental results indicated that reaction temperature and residence time had significant influences on the oxidation reaction, and increasing the two operation parameters could improve both degradation of chemical oxygen demand (COD) and ammonia nitrogen (NH3-N). The COD removal efficiency could reach up to 98.73% at 25 MPa, 773 K and 180.1 s, whereas the destruction efficiency of NH3-N was only 43.71%. We further carried out a kinetic analysis considering the induction period through free radical chain mechanism. It confirms that the power-law rate equation for COD removal was 345 exp(-52200/RT)[COD]1.98[O2]0.17 and for NH3-N removal was 500 exp(-64492.19/RT)[NH3-N]1.87 [O2]0.03. Moreover, the induction time formulations for COD and NH3-N were suspected to be exp(38250/RT)/173 and exp(55690/RT)/15231, respectively. Correspondingly, induction time changed from 2.22 to 5.38 s for COD and 0.38 to 1.38 s for NH3-N. Owing to the catalysis of reactor inner wall surface, more than 97% COD removal was achieved in all samples.

Giant enhancement of surface second-harmonic generation using photorefractive surface waves with diffusion and drift nonlinearities

Giant enhancement of second-harmonic generation (SHG) with 83.4%/W coversion efficiency is obtained, taking advantage of photorefractive surface waves with diffusion and drift nonlinearity. In this method, the self-bending induced by diffusion nonlinearity can be utilized at the surface and can solve the phase-mismatch problem in bulk due to beam self-bending. With drift nonlinearity, an applied external electric filed and background illumination can further constringe surface waves to the surface and consequently enhance SHG, which provides the possibility and flexibility of control.

(2+1)D surface solitons in virtue of the cooperation of nonlocal and local nonlinearities

We introduce a type of (2+1)D surface soliton in virtue of the cooperation of nonlocal and local nonlinearities. Furthermore, taking advantage of diffusion and drift nonlinearity this type of surface soliton is demonstrated theoretically and experimentally in a storintium barium nitrate crystal. The dynamics behavior of the excitation and propagation of this type of surface soliton are studied using the beam-propagation method and the nonlinear equation of light rays.