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1.
PLoS One ; 12(10): e0185198, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29016627

RESUMO

Hepatocellular carcinoma (HCC) presentation is heterogeneous necessitating a variety of therapeutic interventions with varying efficacies and associated prognoses. Poor prognostic patients often undergo non-curative palliative interventions including transarterial chemoembolization (TACE), sorafenib, chemotherapy, or purely supportive care. The decision to pursue one of many palliative interventions for HCC is complex and an economic evaluation comparing these interventions has not been done. This study evaluates the cost-effectiveness of non-curative palliative treatment strategies such as TACE alone or TACE+sorafenib, sorafenib alone, and non-sorafenib chemotherapy compared with no treatment or best supportive care (BSC) among patients diagnosed with HCC between 2007 and 2010 in a Canadian setting. Using person-level data, we estimated effectiveness in life years and quality-adjusted life years (QALYs) along with total health care costs (2013 US dollars) from the health care payer's perspective (3% annual discount). A net benefit regression approach accounting for baseline covariates with propensity score adjustment was used to calculate incremental net benefit to generate incremental cost-effectiveness ratio (ICER) and uncertainty measures. Among 1,172 identified patients diagnosed with HCC, 4.5%, 7.9%, and 5.6%, received TACE alone or TACE+sorafenib, sorafenib, and non-sorafenib chemotherapy clone, respectively. Compared with no treatment or BSC (81.9%), ICER estimates for TACE alone or TACE+sorafenib was $6,665/QALY (additional QALY: 0.47, additional cost: $3,120; 95% CI: -$18,800-$34,500/QALY). The cost-effectiveness acceptability curve demonstrated that if the relevant threshold was $50,000/QALY, TACE alone or TACE+sorafenib, non-sorafenib chemotherapy, and sorafenib alone, would have a cost-effectiveness probability of 99.7%, 46.6%, and 5.5%, respectively. Covariates associated with the incremental net benefit of treatments are age, sex, comorbidity, and cancer stage. Findings suggest that TACE with or without sorafenib is currently the most cost-effective active non-curative palliative treatment approach to HCC. Further research into new combination treatment strategies that afford the best tumor response is needed.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Análise Custo-Benefício , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/economia , Quimioembolização Terapêutica/economia , Quimioembolização Terapêutica/métodos , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/economia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Niacinamida/análogos & derivados , Niacinamida/economia , Niacinamida/uso terapêutico , Cuidados Paliativos/economia , Compostos de Fenilureia/economia , Compostos de Fenilureia/uso terapêutico , Sorafenibe , Resultado do Tratamento
3.
BMJ Case Rep ; 20152015 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-26611482

RESUMO

A 74-year-old man presented with a 2-month history of watery diarrhoea. His complete blood count showed lymphopaenia and marked eosinophilia. Investigations for common infectious causes including Clostridium difficile toxin, stool culture, ova and parasites were negative. Endoscopy revealed extensive colitis and a CT of the abdomen identified numerous large abdominal lymph nodes suspicious for lymphoma. Multiple tissue samples were obtained; colon, mesenteric lymph node and bone marrow biopsy, as well as pleural fluid from a rapidly developing effusion, confirmed the presence of metastatic lymphoma with an immunophenotype most consistent with an aggressive variant of Epstein-Barr virus (EBV)-negative natural killer (NK)-cell lymphoma. The patient's clinical condition rapidly deteriorated and he died shortly following diagnosis. To the best of our knowledge, this is the first case report of a primary gastrointestinal EBV-negative NK-cell lymphoma, and its clinical presentation highlights the importance of a broad differential in the management of chronic diarrhoea.


Assuntos
Diarreia/etiologia , Eosinofilia/etiologia , Neoplasias Gastrointestinais/imunologia , Células Matadoras Naturais , Linfoma/imunologia , Idoso , Doença Crônica , Colonoscopia , Diagnóstico Diferencial , Evolução Fatal , Neoplasias Gastrointestinais/diagnóstico , Herpesvirus Humano 4 , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfoma/diagnóstico , Masculino , Tomografia Computadorizada por Raios X
4.
PLoS One ; 10(9): e0138907, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26398404

RESUMO

The optimal schedule for ultrasonographic surveillance of patients with viral hepatitis for the detection of hepatocellular carcinoma (HCC) remains unclear owing to a lack of reliable studies. We examined the timing of ultrasonography in patients with viral hepatitis-induced HCC and its impact on survival and mortality risk while determining predictors of receiving surveillance before HCC diagnosis. A population-based retrospective cohort analysis of patients with viral hepatitis-induced HCC in Ontario between 2000 and 2010 was performed using data from the Ontario Cancer Registry linked health administrative data. HCC surveillance for 2 years preceding diagnosis was assigned as: i) ≥ 2 abdominal ultrasound screens annually; ii) 1 screen annually; iii) inconsistent screening; and iv) no screening. Survival rates were estimated using the Kaplan-Meier method and parametric models to correct for lead-time bias. Associations between HCC surveillance and the risk of mortality after diagnosis were examined using proportional-hazards regression adjusting for confounding factors. Overall, 1,483 patients with viral hepatitis-induced HCC were identified during the study period; 20.2% received ≥ 1 ultrasound screen annually (routine surveillance) for the 2 years preceding diagnosis. The 5-year survival of those receiving routine surveillance was 31.93% (95% CI: 25.77-38.24%) and 31.84% (95% CI: 25.69-38.14%) when corrected for lead-time bias (HCC sojourn time 70 days and 140 days, respectively). This is contrasted with 20.67% (95% CI: 16.86-24.74%) 5-year survival in those who did not undergo screening. In the fully adjusted model, compared to unscreened patients, routine surveillance was associated with a lower mortality risk and a hazard ratio of 0.76 (95% CI: 0.64-0.91) and 0.81 (95% CI: 0.68-0.97), corrected for the respective lead-time bias. Our findings suggest that routine ultrasonography in patients with viral hepatitis is associated with improved survival and reduced mortality risk in a population-based setting. The data emphasizes the importance of surveillance for timely intervention in HCC-diagnosed patients.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Hepatite B Crônica/diagnóstico por imagem , Hepatite C Crônica/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Detecção Precoce de Câncer , Monitoramento Epidemiológico , Feminino , Hepatite B Crônica/complicações , Hepatite B Crônica/mortalidade , Hepatite C Crônica/complicações , Hepatite C Crônica/mortalidade , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Ontário , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Ultrassonografia
5.
CMAJ Open ; 3(2): E208-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26389099

RESUMO

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) is increasing and survival rates are poor. Our objectives were to estimate the relative survival over time in patients with HCC in Ontario and to examine potential factors associated with excess mortality risk. METHODS: We performed a population-based retrospective cohort analysis involving patients with a diagnosis of HCC in Ontario between 1990 and 2009 using data extracted from the Ontario Cancer Registry. Relative survival was estimated by controlling for background mortality using expected mortality from Ontario life tables. A generalized linear model was used to estimate the excess mortality risk for important factors. RESULTS: A total of 5645 patients had HCC diagnosed during the study period; 4412 (78.2%) of these patients were male. Improvements in 1-year relative survival were observed across all age groups over time: the highest was among those patients less than 60 years of age who had a diagnosis of HCC during 2005-2009, with 1-year survival exceeding 50% for both sexes. However, the overall 5-year relative survival did not exceed 28%. The excess mortality risk decreased with increased years of follow-up, recent diagnosis, and curative or noncurative treatments for HCC, whereas excess mortality risk increased with age. INTERPRETATION: Although improving, the prognosis for HCC remains poor. Our findings highlight the importance of effective prevention and treatment for HCC to reduce the burden of disease and improve health care systems.

6.
J Immunol ; 191(12): 5840-7, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24244021

RESUMO

Germinal centers (GCs) are clusters of activated B cells that form in secondary lymphoid organs during a T-dependent immune response. B cells enter GCs and become rapidly proliferating centroblasts that express the enzyme activation-induced deaminase (AID) to undergo somatic hypermutation and class-switch recombination. Centroblasts then mature into centrocytes to undergo clonal selection. Within the GC, the highest affinity B cell clones are selected to mature into memory or plasma cells while lower affinity clones undergo apoptosis. We reported previously that murine Aicda(-/-) GC B cells have enhanced viability and accumulate in GCs. We now show that murine Aicda(-/-) GC B cells accumulate as centrocytes and inefficiently generate plasma cells. The reduced rate of plasma cell formation was not due to an absence of AID-induced DNA lesions. In addition, we show that the deletion of caspase 8 specifically in murine GC-B cells results in larger GCs and a delay in affinity maturation, demonstrating the importance of apoptosis in GC homeostasis and clonal selection.


Assuntos
Apoptose/fisiologia , Síndrome Linfoproliferativa Autoimune/imunologia , Subpopulações de Linfócitos B/imunologia , Caspase 8/fisiologia , Seleção Clonal Mediada por Antígeno , Citidina Desaminase/fisiologia , Centro Germinativo/imunologia , Síndromes de Imunodeficiência/patologia , Transferência Adotiva , Animais , Antígenos/imunologia , Subpopulações de Linfócitos B/patologia , Caspase 8/genética , Divisão Celular , Citidina Desaminase/deficiência , Citidina Desaminase/genética , Quebras de DNA de Cadeia Dupla , Centro Germinativo/patologia , Imunização , Switching de Imunoglobulina , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmócitos/patologia , Quimera por Radiação , Receptores de Antígenos de Linfócitos B/imunologia , Hipermutação Somática de Imunoglobulina
7.
Proc Natl Acad Sci U S A ; 107(2): 809-14, 2010 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-20080757

RESUMO

An effective immune response requires B cells to produce several classes of antibodies through the process of class switch recombination (CSR). Activation-induced cytidine deaminase initiates CSR by deaminating deoxycytidines at switch regions within the Ig locus. This activity leads to double-stranded DNA break formation at the donor and recipient switch regions that are subsequently synapsed and ligated in a 53BP1-dependent process that remains poorly understood. The DNA damage response E3 ubiquitin ligases RNF8 and RNF168 were recently shown to facilitate recruitment of 53BP1 to sites of DNA damage. Here we show that the ubiquitination pathway mediated by RNF8 and RNF168 plays an integral part in CSR. Using the CH12F3-2 mouse B cell line that undergoes CSR to IgA at high rates, we demonstrate that knockdown of RNF8, RNF168, and 53BP1 leads to a significant decrease in CSR. We also show that 53BP1-deficient CH12F3-2 cells are protected from apoptosis mediated by the MDM2 inhibitor Nutlin-3. In contrast, deficiency in either E3 ubiquitin ligase does not protect cells from Nutlin-3-mediated apoptosis, indicating that RNF8 and RNF168 do not regulate all functions of 53BP1.


Assuntos
Proteínas de Ligação a DNA/genética , Recombinação Genética , Ubiquitina-Proteína Ligases/genética , Animais , Linhagem Celular , Citidina Desaminase/metabolismo , Humanos , Imunoglobulina A/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína 1 de Ligação à Proteína Supressora de Tumor p53 , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/genética
8.
Blood ; 114(3): 547-54, 2009 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-19478044

RESUMO

The germinal center (GC) is a transient lymphoid tissue microenvironment that fosters T cell-dependent humoral immunity. Within the GC, the B cell-specific enzyme, activation-induced cytidine deaminase (AID), mutates the immunoglobulin locus, thereby altering binding affinity for antigen. In the absence of AID, larger GC structures are observed in both humans and mice, but the reason for this phenomenon is unclear. Because significant apoptosis occurs within the GC niche to cull cells that have acquired nonproductive mutations, we have examined whether a defect in apoptosis could account for the larger GC structures in the absence of AID. In this report, we reveal significantly reduced death of B cells in AID(-/-) mice as well as in B cells derived from AID(-/-) bone marrow in mixed bone marrow chimeric mice. Furthermore, AID-expressing B cells show decreased proliferation and survival compared with AID(-/-) B cells, indicating an AID-mediated effect on cellular viability. The GC is an etiologic site for B-cell autoimmunity and lymphomagenesis, both of which have been linked to aberrant AID activity. We report a link between AID-induced DNA damage and B-cell apoptosis that has implications for the development of B-cell disorders.


Assuntos
Apoptose , Linfócitos B/citologia , Citidina Desaminase/fisiologia , Centro Germinativo/citologia , Animais , Autoimunidade/genética , Medula Óssea , Proliferação de Células , Sobrevivência Celular , Citidina Desaminase/deficiência , Citidina Desaminase/genética , Dano ao DNA , Linfoma de Células B/etiologia , Linfoma de Células B/genética , Camundongos , Camundongos Knockout
9.
Nucleic Acids Res ; 33(21): 6733-42, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16314305

RESUMO

V(D)J recombination and class switch recombination are the two DNA rearrangement events used to diversify the mouse and human antibody repertoires. While their double strand breaks (DSBs) are initiated by different mechanisms, both processes use non-homologous end joining (NHEJ) in the repair phase. DNA mismatch repair elements (MSH2/MSH6) have been implicated in the repair of class switch junctions as well as other DNA DSBs that proceed through NHEJ. MSH2 has also been implicated in the regulation of factors such as ATM and the MRN (Mre11, Rad50, Nbs1) complex, which are involved in V(D)J recombination. These findings led us to examine the role of MSH2 in V(D)J repair. Using MSH2-/- and MSH2+/+ mice and cell lines, we show here that all pathways involving MSH2 are dispensable for the generation of an intact pre-immune repertoire by V(D)J recombination. In contrast to switch junctions and other DSBs, the usage of terminal homology in V(D)J junctions is not influenced by MSH2. Thus, whether the repair complex for V(D)J recombination is of a canonical NHEJ type or a separate microhomology-mediated-end joining (MMEJ) type, it does not involve MSH2. This highlights a distinction between the repair of V(D)J recombination and other NHEJ reactions.


Assuntos
Rearranjo Gênico do Linfócito B , Proteína 2 Homóloga a MutS/fisiologia , Animais , Sequência de Bases , Células da Medula Óssea/imunologia , Linhagem Celular , Reparo do DNA , Fragmentos de Imunoglobulinas/química , Fragmentos de Imunoglobulinas/genética , Região de Junção de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Camundongos , Camundongos Knockout , Proteína 2 Homóloga a MutS/genética , Recombinação Genética
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