Tibor A. Zwimpfer

Dr. Tibor A. Zwimpfer


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 November 2025 in JAMA Network Open
Verified
Journal Article
Open access
SPStamatios Petousis
Stamatios Petousis
IKIlker Kahramanoglu
Ilker Kahramanoglu
CAChristian Appenzeller-Herzog
Christian Appenzeller-Herzog
MAMartina A. Angeles
Martina A. Angeles
CMChrysoula Margioula-Siarkou
Chrysoula Margioula-Siarkou
TZTibor A. Zwimpfer
Tibor A. Zwimpfer
Importance: First-line maintenance therapy with poly(adenosine diphosphate-ribose) polymerase inhibitors (PARP inhibitors) after platinum-based chemotherapy improves progression-free survival (PFS) in advanced epithelial ovarian cancer (EOC), particularly in patients with BRCA -variant or homologous recombination-deficient tumors. However, overall survival (OS) benefits remain uncertain, and toxic effect profiles emphasize the need for optimized patient and agent selection. Objective: To evaluate the efficacy and safety of first-line PARP inhibitor maintenance therapy compared with chemotherapy alone in advanced-stage EOC, with subgroup analyses by BRCA and HRD status, up-front or interval surgery, chemotherapy response, and residual disease. Data sources: Medline, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched from database inception to August 19, 2024. Study Selection: Randomized clinical trials and prospective 2-arm studies evaluating PARP inhibitor maintenance therapy in patients with advanced-stage EOC responding to first-line platinum-based chemotherapy were included. Data Extraction and Synthesis: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline was followed in reporting this study. Data were independently extracted by 2 reviewers. Random-effects models were used for meta-analysis. Risk of bias was assessed with Cochrane risk of bias and certainty of evidence with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Main Outcomes and Measures: Primary outcomes were PFS and OS; secondary outcomes included high-grade adverse events. Results: A total of 7 randomized clinical trials with 4013 patients with advanced-stage epithelial ovarian cancer responding to first-line platinum-based chemotherapy were included. PARP inhibitor maintenance was associated with improved PFS in the overall population (hazard ratio [HR], 0.57; 95% CI, 0.46-0.70; high certainty) and in all molecular subgroups except the homologous recombination proficient group ( BRCA variant: HR, 0.40; 95% CI, 0.35-0.45; BRCA wild type: HR, 0.62; 95% CI, 0.44-0.86; homologous recombination deficient: HR, 0.44; 95% CI, 0.39-0.50; all high certainty). PFS benefits were consistent across surgical timing, chemotherapy responses, and residual disease; for example, surgical timing had HRs of 0.51 (95% CI, 0.31-0.84) for neoadjuvant chemotherapy and 0.54 (95% CI, 0.36-0.81) for primary cytoreductive surgery (all high certainty). No molecular subgroup showed a statistically significant OS improvement (high to low certainty). High-grade adverse events were more common in the PARP inhibitor group (HR, 2.40; 95% CI, 1.16-4.93; high certainty). Observed treatment efficacy and toxic effects varied across PARP inhibitor regimens; for example, the risk ratio for any recurrence or death in the overall study group ranged from 0.53 (95% CI, 0.40-0.70) for senaparib to 0.83 (95% CI, 0.68-1.00) for olaparib, while the risk ratio for high-grade adverse events ranged from 1.15 (95% CI, 0.64-2.06) for veliparib to 4.73 (95% CI, 2.77-8.07) for niraparib. Conclusions and Relevance: In this study, no subgroup showed an association between first-line PARP inhibitor maintenance therapy in advanced-stage EOC and improved OS, and findings suggest that the consistency of associated PFS benefits may vary, particularly in homologous recombination proficient and BRCA wild type tumors. Variability in efficacy and toxic effects across subgroups and PARP inhibitor regimens underscores the importance of individualized treatment decisions.

4 June 2024 in Frontiers in Oncology
Verified
Journal Article
Open access
PDF file
NSNadja Stiegeler
Nadja Stiegeler
DGDale W. Garsed
Dale W. Garsed
GAGeorge Au-Yeung
George Au-Yeung
DBDavid D. L. Bowtell
David D. L. Bowtell
VHViola Heinzelmann-Schwarz
Viola Heinzelmann-Schwarz
TZTibor A. Zwimpfer
Tibor A. Zwimpfer
Approximately 50% of tubo-ovarian high-grade serous carcinomas (HGSCs) have functional homologous recombination-mediated (HR) DNA repair, so-called HR-proficient tumors, which are often associated with primary platinum resistance (relapse within six months after completion of first-line therapy), minimal benefit from poly(ADP‐ribose) polymerase (PARP) inhibitors, and shorter survival. HR-proficient tumors comprise multiple molecular subtypes including cases with CCNE1 amplification, AKT2 amplification or CDK12 alteration, and are often characterized as “cold” tumors with fewer infiltrating lymphocytes and decreased expression of PD-1/PD-L1. Several new treatment approaches aim to manipulate these negative prognostic features and render HR-proficient tumors more susceptible to treatment. Alterations in multiple different molecules and pathways in the DNA damage response are driving new drug development to target HR-proficient cancer cells, such as inhibitors of the CDK or P13K/AKT pathways, as well as ATR inhibitors. Treatment combinations with chemotherapy or PARP inhibitors and agents targeting DNA replication stress have shown promising preclinical and clinical results. New approaches in immunotherapy are also being explored, including vaccines or antibody drug conjugates. Many approaches are still in the early stages of development and further clinical trials will determine their clinical relevance. There is a need to include HR-proficient tumors in ovarian cancer trials and to analyze them in a more targeted manner to provide further evidence for their specific therapy, as this will be crucial in improving the overall prognosis of HGSC and ovarian cancer in general.

6 May 2022 in BMC Cancer
Verified
Journal Article
Open access
PDF file
PMPamela M. J. McLaughlin
Pamela M. J. McLaughlin
MKMaximilian Klar
Maximilian Klar
TZTibor A. Zwimpfer
Tibor A. Zwimpfer
GDGilles Dutilh
Gilles Dutilh
MVMarcus Vetter
Marcus Vetter
VHViola Heinzelmann-Schwarz
Viola Heinzelmann-Schwarz
Background: A high percentage of epithelial ovarian cancers (EOC) express the estrogen receptor (ER), which is an ideal target for endocrine therapy. Letrozole is a proven, potent aromatase inhibitor, extensively tested and used in the treatment of ER positive breast cancer. In addition, it seems a potent drug for patients with heavily pre-treated OC as demonstrated in several distinctive settings. However, it has never been evaluated prospectively in a maintenance setting for ovarian cancer after standard of care. The here proposed trial aims to define a population of EOC patients, who would benefit from the effectiveness of the generic agent letrozole, with little expected toxicity and thus beneficial impact on overall quality of life (QoL). Methods: In this international multicenter randomized, placebo-controlled phase III trial at clinical centers in Switzerland, Germany and Austria, we plan to include 540 patients with primary, newly diagnosed FIGO Stage II to IV and histologically confirmed low- or high-grade serous or endometrioid epithelial ovarian/fallopian tube/peritoneal cancer. Patients are randomized in a 1:1 ratio into two groups: receiving blinded study treatment (letrozole or placebo tablets). When assuming a HR of 0.7, a median PFS of 18 months in the control arm and a median PFS of 25.7 months in the treatment arm, a two-sided alpha level of 5%, 3.5 years recruitment and 1.5 years observation time, we expect 330 events to have occurred within these 5 years in the total cohort yielding a power of 90%. Follow-up data for the whole cohort will be collected for up to 10 years and for the low-grade cancer for up to 12 years. Discussion: The here proposed randomized phase III trial aims to identify patients with EOC in the maintenance setting, who benefit from the effectiveness of the letrozole, by proving its efficacy whilst maintaining a high standard of QoL due to the limited toxicity expected in comparison to the current alternative drugs on the market for this treatment phase. Trial registration: This trial is registered at clinicaltrials.gov under the identifier NCT04111978. Registered 02 October 2019.

5 June 2024 in Clinical Cancer Research
Verified
Journal Article
Open access
PDF file
FSFlurina Annacarina Maria Saner
Flurina Annacarina Maria Saner
KTKazuaki Takahashi
Kazuaki Takahashi
TBTimothy Budden
Timothy Budden
APAhwan Pandey
Ahwan Pandey
DADinuka Ariyaratne
Dinuka Ariyaratne
DGDale W. Garsed
Dale W. Garsed
Purpose: The purpose of this study was to evaluate RB1 expression and survival across ovarian carcinoma histotypes and how co-occurrence of BRCA1 or BRCA2 (BRCA) alterations and RB1 loss influences survival in tubo-ovarian high-grade serous carcinoma (HGSC). Experimental Design: RB1 protein expression was classified by immunohistochemistry in ovarian carcinomas of 7,436 patients from the Ovarian Tumor Tissue Analysis consortium. We examined RB1 expression and germline BRCA status in a subset of 1,134 HGSC, and related genotype to overall survival (OS), tumor-infiltrating CD8+ lymphocytes, and transcriptomic subtypes. Using CRISPR-Cas9, we deleted RB1 in HGSC cells with and without BRCA1 alterations to model co-loss with treatment response. We performed whole-genome and transcriptome data analyses on 126 patients with primary HGSC to characterize tumors with concurrent BRCA deficiency and RB1 loss. Results: RB1 loss was associated with longer OS in HGSC but with poorer prognosis in endometrioid ovarian carcinoma. Patients with HGSC harboring both RB1 loss and pathogenic germline BRCA variants had superior OS compared with patients with either alteration alone, and their median OS was three times longer than those without pathogenic BRCA variants and retained RB1 expression (9.3 vs. 3.1 years). Enhanced sensitivity to cisplatin and paclitaxel was seen in BRCA1-altered cells with RB1 knockout. Combined RB1 loss and BRCA deficiency correlated with transcriptional markers of enhanced IFN response, cell-cycle deregulation, and reduced epithelial–mesenchymal transition. CD8+ lymphocytes were most prevalent in BRCA-deficient HGSC with co-loss of RB1. Conclusions: Co-occurrence of RB1 loss and BRCA deficiency was associated with exceptionally long survival in patients with HGSC, potentially due to better treatment response and immune stimulation.

9 April 2021 in BMC Pregnancy and Childbirth
Verified
Journal Article
Open access
PDF file
TZTibor A. Zwimpfer
Tibor A. Zwimpfer
CMCécile Monod
Cécile Monod
KRKatharina Redling
Katharina Redling
HWHeike Willi
Heike Willi
MTMartin Takes
Martin Takes
IHIrene Hösli
Irene Hösli
Background: Pseudoaneurysm of the uterine artery (UPA) is a rare cause of potentially life-threatening hemorrhage during pregnancy and puerperium. It is an uncommon condition that mainly occurs after traumatic injury to a vessel following pelvic surgical intervention, but also has been reported based on underlying endometriosis. There is an increased risk of developing UPA during pregnancy. Diagnosis includes clinical symptoms, with severe abdominal pain and is confirmed by sonographic or magnetic resonance imaging (MRI). Due to its potential risk of rupture, with a subsequent hypovolemic maternal shock and high fetal mortality, an interdisciplinary treatment should be considered expeditiously. Case presentation: We present the case of a 34-year old pregnant symptomatic patient, where a large UPA was detected at 26 weeks, based on deep infiltrating endometriosis (DIE). The UPA was successfully treated by selective arterial embolization. After embolization, the pain decreased but the woman still required intravenous analgesics during follow-up. At 37 weeks she developed a sepsis from the intravenous catheter which led to a cesarean section and delivery of a healthy boy. She was discharged 10 days postpartum. Conclusions: UPA should be considered in pregnant women with severe abdominal and pelvic pain, once other obstetrical factors have been excluded. DIE might be the underlying diagnosis. It is a rare but potentially life-threatening condition for mother and fetus.

9 November 2020 in BMC Surgery
Verified
Journal Article
Open access
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TZTibor A. Zwimpfer
Tibor A. Zwimpfer
DLDominik Lacher
Dominik Lacher
BFBernhard Fellmann-Fischer
Bernhard Fellmann-Fischer
MMMichael Mueller
Michael Mueller
Background: Vision is an essential element of laparoscopic surgery that defines the outcome of an operation in regards to time, mistakes and precision. A 3-dimensional (3D) perspective may improve vision during an operation. Therefore, this study was designed to compare 3D versus 2-dimensional (2D) perspectives using a pelvitrainer model. Methods: Fifty candidates were divided into 3 categories based on different experience levels. The candidates were randomised into two groups, with each group performing the same 4 standardised tasks. Group A approached the tasks first with 3D high definition and in a second turn with 2D high definition. Group B carried out the tasks with the systems in reverse order. Task completion time and the number of mistakes made for each task were recorded. After completing the tasks, participants answered questions concerning the two systems. Results: Group A was, on average, 20% faster at all four tasks and made approximately 18% fewer mistakes in two of the tasks in comparison to group B. The experts significantly benefited from the 3D system in terms of accuracy compared to non-experts and students. The students demonstrated a significantly greater benefit from the 3D system when performing non-linear, continuous movements. Loss of concentration occurred at the same rate for subjects using the 2D and 3D systems. Nausea and dizziness were reported only when working with the 3D system. 91% found the 3D system advantageous for accomplishing the tasks. Conclusions: Irrespective of experience level, 3D laparoscopy shows advantages in saving time, increasing accuracy and reducing mistakes. These benefits were also accompanied by subjective advantages that were noted by the participants. However, the more complex the task, the less significant the benefit of the 3D system and some people feel handicapped by the eyewear.