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Syrbu, Sergei

https://orcid.org/0000-0003-4620-7923

Mayo Clinic

University of Iowa

Citations 60

Diagnosis-to-Treatment Interval Is an Important Clinical Factor in Newly Diagnosed Diffuse Large B-Cell Lymphoma and Has Implication for Bias in Clinical Trials
Maurer, Matthew J. , Ghesquières, Hervé , Link, Brian K. , Jais, Jean‐Philippe, Thompson, Carrie A. , Haïoun, Corinne , Allmer, Cristine, Johnston, Patrick B. , Delarue, Richard, Micallef, Ivana N. , Peyrade, Frédéric, Inwards, David J. , Ketterer, Nicolas , Farooq, Umar , Fitoussi, Olivier , Macon, William R. , Molina, Thierry Jo , Syrbu, Sergei , Weiner, George J. , Ansell, Stephen M. , Salles, Gilles , Tilly, Hervé , Nowakowski, Grzegorz S. , Molina, Thierry J, Salles, Gilles A, Maurer, Matthew , Link, Brian K , Farooq, Umar , Salles, Gilles A , Weiner, George , Jaïs, Jean‐Philippe , Habermann, Thomas M. , Feldman, Andrew L. , Slager, Susan L. , Cerhan, James R. , Witzig, Thomas E. , Syrbu, Sergei

Journal of Clinical Oncology | April 19, 2018 | Volume: 36 | Issue: 16 | Pages: 1603-1610

10.1200/jco.2017.76.5198 Get It

Purpose Selection bias in clinical trials has consequences for scientific validity and applicability of study results to the general population. There is concern that patients with clinically aggressive disease may not have enrolled in recent diffuse large B-cell lymphoma (DLBCL) trials due to the consent process and the inability to delay therapy for eligibility evaluation. We have examined the diagnosis-to-treatment interval (DTI) and its association with clinical factors and outcome in a clinic-based observational cohort of patients with DLBCL from the United States. Validation of results was performed in an independent, clinical trial-based cohort from Europe. Patients and Methods Patients were prospectively enrolled in the University of Iowa and Mayo Clinic Specialized Programs of Research Excellence Molecular Epidemiology Resource (MER; N = 986) or the Lymphoma Study Association (LYSA) LNH-2003 clinical trials program (N = 1,444). All patients received anthracycline-based immunochemotherapy at initial diagnosis. Associations of DTI with clinical factors and outcome were examined. Outcome was assessed using event-free survival at 24 months from diagnosis (EFS24). Results Median (range) DTI was 15 days (0 to 155 days in the MER and 23 days (0 to 215 days) in LYSA. Shorter DTI was strongly associated with adverse clinical factors, including elevated lactate dehydrogenase levels, poor performance status, B symptoms, and higher International Prognostic Index in both cohorts (all P < .001). Longer DTI was associated with improved EFS24 in both the MER (per-week odds ratio, 0.80; 95% CI, 0.74 to .0.87) and LYSA (per-week odds ratio, 0.90; 95% CI, 0.86 to 0.94); association with EFS24 remained significant after adjustment for International Prognostic Index. Conclusion DTI is strongly associated with prognostic clinical factors and outcome in newly diagnosed DLBCL. DTI should be reported in all clinical trials of newly diagnosed DLBCL and future trials should take steps to avoid selection bias due to treatment delay.
Event‐free survival at 24 months captures central nervous system relapse of systemic diffuse large B‐cell lymphoma in the immunochemotherapy era
Thanarajasingam, Gita , Maurer, Matthew J. , Farooq, Umar , Johnston, Patrick B., Thompson, Carrie A. , Bennani, Nabila Nora, Ansell, Stephen M. , Porrata, Luis F. , Macon, William R. , Syrbu, Sergei , Link, Brian K. , Nowakowski, Grzegorz S. , Bennani, Nabila N, Maurer, Matthew , Link, Brian K , Farooq, Umar , Johnston, Patrick B. , Cerhan, James R. , Habermann, Thomas M. , Witzig, Thomas E. , Syrbu, Sergei

British Journal of Haematology | September 29, 2017 | Volume: 183 | Issue: 1 | Pages: 149-152

10.1111/bjh.14922 Get It

Clinical heterogeneity of diffuse large B cell lymphoma following failure of front‐line immunochemotherapy
Farooq, Umar , Maurer, Matthew J. , Thompson, Carrie A. , Thanarajasingam, Gita , Inwards, David J. , Micallef, Ivana N. , Macon, William R. , Syrbu, Sergei , Lin, Tasha , Lin, Yi , Ansell, Stephen M. , Nowakowski, Grzegorz S. , Link, Brian K. , Micallef, Ivana, Macon, William, Farooq, Umar , Habermann, Thomas M. , Cerhan, James R. , Maurer, Matthew , Link, Brian K , Lin, Yi , Syrbu, Sergei

British Journal of Haematology | June 27, 2017 | Volume: 179 | Issue: 1 | Pages: 50-60

10.1111/bjh.14813 Get It

Summary This study aimed to describe the patterns of care and outcomes of diffuse large B cell lymphoma ( DLBCL ) after failure of front line anthracycline‐based immunochemotherapy ( IC ). Patients with newly diagnosed lymphoma were prospectively enrolled in Molecular Epidemiology Resource ( MER ) of the University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellzence. All DLBCL and primary mediastinal B‐cell lymphoma ( PMBL ) patients treated with front‐line anthracycline‐based IC were followed for relapse. Patients with relapse on follow‐up and subsequently retreated were included in this analysis. 1039 patients received anthracycline‐based IC between 2002 and 2012, of which 244 relapsed and were subsequently retreated. Across all therapies, overall survival at 4 years ( OS 4) from relapse was 28% and 103 patients ultimately underwent autologous haematopoietic cell transplant (auto HCT ) with OS 4 from auto HCT of 51%. Patients relapsing after 12 months from initial diagnosis had OS 4 of 47% but those with a transient or no response to initial therapy had OS 4 of only 13%. Outcomes of relapsed or refractory DLBCL differ substantially when categorized by response to initial therapy, timing of relapse and opportunity to undergo auto HCT . The design and interpretation of uncontrolled trials should account for this heterogeneity in patients with relapsed DLBCL .
Cohort Profile: The Lymphoma Specialized Program of Research Excellence (SPORE) Molecular Epidemiology Resource (MER) Cohort Study
Link, Brian K. , Syrbu, Sergei , Thompson, Carrie A. , Farooq, Umar , Novak, Anne J. , Allmer, Cristine, Lunde, Julianne J. , Macon, William R. , Inwards, David J. , Johnston, Patrick B. , Micallef, Ivana N. , Nowakowski, Grzegorz S. , Ansell, Stephen M. , Weiner, George J. , Cerhan, James R. , Habermann, Thomas M. , Maurer, Matthew J. , Feldman, Andrew L. , Farooq, Umar , Slager, Susan L. , Kay, Neil E. , Witzig, Thomas E. , Link, Brian K , Weiner, George , Syrbu, Sergei

International Journal of Epidemiology | June 12, 2017 | Volume: 46 | Issue: 6 | Pages: 1753-1754i

10.1093/ije/dyx119 Get It

Early event status informs subsequent outcome in newly diagnosed follicular lymphoma
Bachy, Emmanuel , Ghesquières, Hervé , Ansell, Stephen M. , Nowakowski, Grzegorz S. , Thompson, Carrie A. , Inwards, David J. , Allmer, Cristine, Chassagne‐Clément, Catherine, Nicolas‐Virelizier, Emmanuelle , Sebban, Catherine, Lebras, Laure , Macon, William R. , Feldman, Andrew L. , Syrbu, Sergei , Traverse‐Glehan, Alexandra, Coiffier, Bertrand , Weiner, George J. , Salles, Gilles , Link, Brian K. , Maurer, Matthew J. , Sarkozy, Clémentine , Slager, Susan L. , Witzig, Thomas E. , Habermann, Thomas M. , Cerhan, James R. , Feldman, Andrew L , Link, Brian K , Salles, Gilles A , Weiner, George , Bachy, Emmanuel , Syrbu, Sergei

American Journal of Hematology | July 28, 2016 | Volume: 91 | Issue: 11 | Pages: 1096-1101

10.1002/ajh.24492 Get It

Recent advances in follicular lymphoma (FL) have resulted in prolongation of overall survival (OS). Here we assessed if early events as defined by event‐free survival (EFS) at 12 and 24 months from diagnosis (EFS12/EFS24) can inform subsequent OS in FL. 920 newly diagnosed grade 1‐3A FL patients enrolled on the University of Iowa/Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource (MER) from 2002‐2012 were initially evaluated. EFS was defined as time from diagnosis to progression, relapse, re‐treatment, or death due to any cause. OS was compared to age‐and‐sex‐matched survival in the general US population using standardized mortality ratios (SMR) and 95% confidence intervals (CI). We used a cohort of 412 FL patients from two Lyon, France hospital registries for independent replication. Patients who failed to achieve EFS12 had poor subsequent OS (MER SMR = 3.72, 95%CI: 2.78‐4.88; Lyon SMR = 8.74, 95%CI: 5.41‐13.36). Conversely, patients achieving EFS12 had no added mortality beyond the background population (MER SMR = 0.73, 95%CI: 0.56‐0.94, Lyon SMR = 1.02, 95%CI: 0.58‐1.65). Patients with early events after immunochemotherapy had especially poor outcomes (EFS12 failure: MER SMR = 17.63, 95%CI:11.97‐25.02, Lyon SMR = 19.10, 95%CI:9.86‐33.36; EFS24 failure: MER SMR = 13.02, 95%CI:9.31‐17.74, Lyon SMR = 7.22, 95%CI:4.13‐11.74). In a combined dataset of all patients from both cohorts, baseline FLIPI was no longer informative in EFS12 achievers. Reassessment of patient status at 12 months from diagnosis in follicular lymphoma patients, or at 24 months in patients treated with immunochemotherapy, is a strong predictor of subsequent overall survival in FL. Early event status provides a simple, clinically relevant endpoint for studies assessing outcome in FL. Am. J. Hematol. 91:1096–1101, 2016. © 2016 Wiley Periodicals, Inc.
Personalized risk prediction for event‐free survival at 24 months in patients with diffuse large B‐cell lymphoma
Jaïs, Jean‐Philippe , Ghesquières, Hervé , Thompson, Carrie A. , Thiéblemont, Catherine , Micallef, Ivana N. , Porrata, Luis F. , Nowakowski, G. S., Casasnovas, Olivier , Bologna, Serge, Morrison, Vicki A., Macon, William R. , Copie‐Bergman, Christiane , Feldman, Andrew L. , Syrbu, Sergei , Kurtin, Paul J. , Gascoyne, Randy D. , Li, Hailun , Allmer, Cristine, Ansell, Stephen M. , Link, Brian K. , Salles, Gilles , Tilly, Hervé , Nowakowski, Gregorz S, Maurer, Matthew J. , Witzig, Thomas E. , Hong, Fangxin , Haïoun, Corinne , Ribrag, Vincent , Morschhauser, Franck , Peterson, Bruce A. , Kahl, Brad S. , Slager, Susan L. , Habermann, Thomas M. , Cerhan, James R. , Feldman, Andrew L , Link, Brian K , Salles, Gilles A , Syrbu, Sergei , Casasnovas, René-Olivier

American Journal of Hematology | October 22, 2015 | Volume: 91 | Issue: 2 | Pages: 179-184

10.1002/ajh.24223 Get It

We recently defined event‐free survival at 24 months (EFS24) as a clinically relevant outcome for patients with DLBCL. Patients who fail EFS24 have very poor overall survival, while those who achieve EFS24 have a subsequent overall survival equivalent to that of the age‐ and sex‐matched general population. Here, we develop and validate a clinical risk calculator (IPI24) for EFS24. Model building was performed on a discovery dataset of 1,348 patients with DLBCL and treated with anthracycline‐based immunochemotherapy. A multivariable model containing age, Ann Arbor stage, normalized serum LDH, ALC, ECOG performance status, bulky disease, and sex was identified. The model was then applied to an independent validation dataset of 1,177 DLBCL patients. The IPI24 score estimates the probability of failing to achieve the EFS24 endpoint for an individual patient. The IPI24 model showed superior discriminatory ability (c‐statistic = 0.671) in the validation dataset compared to the IPI (c‐statistic = 0.649) or the NCCN‐IPI (c‐statistic = 0.657). After recalibration of the model on the combined dataset, the median predicted probability of failing to achieve EFS24 was 36% (range, 12–88%), and the IPI24 showed an EFS24 gradient in all IPI groups. The IPI24 also identified a significant percentage of patients with high risk disease, with over 20% of patients having a 50% or higher risk of failing to achieve EFS24. The IPI24 provides an individual patient level probability of achieving the clinically relevant EFS24 endpoint. It can be used via electronic apps. Am. J. Hematol. 91:179–184, 2016. © 2015 Wiley Periodicals, Inc.
Elevated serum levels of IL-2R, IL-1RA, and CXCL9 are associated with a poor prognosis in follicular lymphoma
Mir, Muhammad A. , Maurer, Matthew J. , Ziesmer, Steven C., Macon, William R. , Link, Brian K. , Syrbu, Sergei , Friedberg, Jonathan W. , Press, Oliver W. , Novak, Anne J. , Ansell, Stephen M. , Slager, Susan L. , Habermann, Thomas M. , Witzig, Thomas E. , LeBlanc, Michael , Cerhan, James R. , Maurer, Matthew , Press, Oliver , Link, Brian K , Syrbu, Sergei

Blood | November 24, 2014 | Volume: 125 | Issue: 6 | Pages: 992-998

10.1182/blood-2014-06-583369 Get It

Key Points Elevated IL-2R, IL-1RA, and CXCL9 are associated with shorter event-free survival in newly diagnosed FL, treated with chemoimmunotherapy. Increased serum IL-12 and IL-1RA is associated with shorter event-free survival in patients who were observed or treated with rituximab alone.
Event-Free Survival at 24 Months Is a Robust End Point for Disease-Related Outcome in Diffuse Large B-Cell Lymphoma Treated With Immunochemotherapy
Maurer, Matthew J. , Ghesquières, Hervé , Jais, Jean‐Philippe, Haïoun, Corinne , Thompson, Carrie A. , Delarue, Richard, Micallef, Ivana N. , Peyrade, Frédéric, Macon, William R. , Molina, Thierry Jo , Ketterer, Nicolas , Syrbu, Sergei , Fitoussi, Olivier , Kurtin, Paul J. , Allmer, Cristine, Nicolas‐Virelizier, Emmanuelle , Link, Brian K. , Salles, Gilles , Tilly, Hervé , Cerhan, James R. , Jaïs, Jean‐Philippe , Witzig, Thomas E. , Slager, Susan L. , Habermann, Thomas M. , Maurer, Matthew , Cerhan, James R , Link, Brian K , Salles, Gilles A , Syrbu, Sergei

Journal of Clinical Oncology | February 19, 2014 | Volume: 32 | Issue: 10 | Pages: 1066-1073

10.1200/jco.2013.51.5866 Get It

Purpose Studies of diffuse large B-cell lymphoma (DLBCL) are typically evaluated by using a time-to-event approach with relapse, re-treatment, and death commonly used as the events. We evaluated the timing and type of events in newly diagnosed DLBCL and compared patient outcome with reference population data. Patients and Methods Patients with newly diagnosed DLBCL treated with immunochemotherapy were prospectively enrolled onto the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource (MER) and the North Central Cancer Treatment Group NCCTG-N0489 clinical trial from 2002 to 2009. Patient outcomes were evaluated at diagnosis and in the subsets of patients achieving event-free status at 12 months (EFS12) and 24 months (EFS24) from diagnosis. Overall survival was compared with age- and sex-matched population data. Results were replicated in an external validation cohort from the Groupe d'Etude des Lymphomes de l'Adulte (GELA) Lymphome Non Hodgkinien 2003 (LNH2003) program and a registry based in Lyon, France. Results In all, 767 patients with newly diagnosed DLBCL who had a median age of 63 years were enrolled onto the MER and NCCTG studies. At a median follow-up of 60 months (range, 8 to 116 months), 299 patients had an event and 210 patients had died. Patients achieving EFS24 had an overall survival equivalent to that of the age- and sex-matched general population (standardized mortality ratio [SMR], 1.18; P = .25). This result was confirmed in 820 patients from the GELA study and registry in Lyon (SMR, 1.09; P = .71). Simulation studies showed that EFS24 has comparable power to continuous EFS when evaluating clinical trials in DLBCL. Conclusion Patients with DLBCL who achieve EFS24 have a subsequent overall survival equivalent to that of the age- and sex-matched general population. EFS24 will be useful in patient counseling and should be considered as an end point for future studies of newly diagnosed DLBCL.
Rates and Outcomes of Follicular Lymphoma Transformation in the Immunochemotherapy Era: A Report From the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource
Link, Brian K. , Maurer, Matthew J. , Nowakowski, Grzegorz S. , Ansell, Stephen M. , Macon, William R. , Syrbu, Sergei , Thompson, Carrie A. , Inwards, David J. , Johnston, Patrick B. , Cerhan, James R. , Slager, Susan L. , Colgan, Joseph P. , Witzig, Thomas E. , Habermann, Thomas M. , Maurer, Matthew , Cerhan, James R , Link, Brian K , Syrbu, Sergei

Journal of Clinical Oncology | July 30, 2013 | Volume: 31 | Issue: 26 | Pages: 3272-3278

10.1200/jco.2012.48.3990 Get It

Purpose This study sought to characterize transformation incidence and outcome for patients with follicular lymphoma (FL) in a prospective observational series begun after diffusion of rituximab use. Patients and Methods Patients with newly diagnosed FL were prospectively enrolled onto the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource from 2002 to 2009. Patients were actively followed for re-treatment, clinical or pathologic transformation, and death. Risk of transformation was analyzed via time to transformation by using death as a competing risk. Results In all, there were 631 patients with newly diagnosed grade 1 to 3a FL who had a median age at enrollment of 60 years. At a median follow-up of 60 months (range, 11 to 110 months), 79 patients had died, and 60 patients developed transformed lymphoma, of which 51 were biopsy proven. The overall transformation rate at 5 years was 10.7%, with an estimated rate of 2% per year. Increased lactate dehydrogenase was associated with increased risk of transformation. Transformation rate at 5 years was highest in patients who were initially observed and lowest in patients who initially received rituximab monotherapy (14.4% v 3.2%; P = .021). Median overall survival following transformation was 50 months and was superior in patients with transformation greater than 18 months after FL diagnosis compared with patients with earlier transformation (5-year overall survival, 66% v 22%; P < .001). Conclusion Follicular transformation rates in the immunochemotherapy era are similar to risk of death without transformation and may be lower than reported in older series. Post-transformation prognosis is substantially better than described in older series. Initial management strategies may influence the risk of transformation.
Elevated Serum Free Light Chains Are Associated With Event-Free and Overall Survival in Two Independent Cohorts of Patients With Diffuse Large B-Cell Lymphoma
Maurer, Matthew J. , Micallef, Ivana N. , Cerhan, James R. , Katzmann, Jerry A., Link, Brian K. , Inwards, David J. , Ansell, Stephen M. , Porrata, Luis F. , Johnston, Patrick B. , Nowakowski, Grzegorz S. , Thompson, Carrie A. , Syrbu, Sergei , Kurtin, Paul J. , Macon, William R. , Nikcevich, Daniel A., Colgan, Joseph P. , Habermann, Thomas M. , Markovic, Svetomir N. , Gupta, Mamta , Witzig, Thomas E. , Maurer, Matthew , Cerhan, James R , Link, Brian K , Syrbu, Sergei

Journal of Clinical Oncology | March 8, 2011 | Volume: 29 | Issue: 12 | Pages: 1620-1626

10.1200/jco.2010.29.4413 Get It

Purpose The serum free light chain (FLC) assay quantitates free kappa (κ) and free lambda (λ) immunoglobulin light chains. This assay has prognostic value in plasma cell proliferative disorders. There are limited data on serum FLC in B-cell malignancies. Patients and Methods The association of pretreatment FLC with event-free survival (EFS) and overall survival (OS) in diffuse large B-cell lymphoma (DLBCL) was evaluated in 76 patients from the North Central Cancer Treatment Group trial N0489 (NCT00301821) and 219 patients from the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource (MER). Published reference ranges were used to define an elevated FLC or an abnormal κ:λ FLC ratio. Results Elevated FLC or abnormal κ:λ FLC ratio was present in 32% and 14% of patients, respectively. Patients with elevated FLC had an inferior OS and EFS in both cohorts compared with patients with normal FLC (N0489: EFS hazard ratio [HR], 3.06; OS HR, 3.16; both P < .02; MER: EFS HR, 2.42; OS HR, 3.40; both P < .001; combined EFS HR, 2.57; OS HR, 3.74; both P < .001). All associations remained significant for EFS and OS after adjusting for the International Prognostic Index (IPI). Abnormal κ:λ FLC ratio was modestly associated with outcome in the combined group (EFS HR, 1.61; OS HR, 1.67; both P = .07), but not in patients without corresponding elevated κ or λ. Elevated FLC was the strongest predictor of outcome in multivariable models with the IPI components. Conclusion Increased serum FLC is an independent, adverse prognostic factor for EFS and OS in DLBCL and warrants further evaluation as a biomarker in DLBCL.