Bartłomiej Tomasik

Dr. Bartłomiej Tomasik

Department of Oncology and Radiotherapy, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland
orcid

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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6 March 2023 in EP Europace
Verified
Journal Article
Open access
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MGMelanie Grehn
Melanie Grehn
SMStefano Mandija
Stefano Mandija
MMMarcin Miszczyk
Marcin Miszczyk
DKDavid Krug
David Krug
Bartłomiej TomasikBartłomiej Tomasik
Bartłomiej Tomasik
JVJoost J C Verhoeff
Joost J C Verhoeff
The EU Horizon 2020 Framework-funded Standardized Treatment and Outcome Platform for Stereotactic Therapy Of Re-entrant tachycardia by a Multidisciplinary (STOPSTORM) consortium has been established as a large research network for investigating STereotactic Arrhythmia Radioablation (STAR) for ventricular tachycardia (VT). The aim is to provide a pooled treatment database to evaluate patterns of practice and outcomes of STAR and finally to harmonize STAR within Europe. The consortium comprises 31 clinical and research institutions. The project is divided into nine work packages (WPs): (i) observational cohort; (ii) standardization and harmonization of target delineation; (iii) harmonized prospective cohort; (iv) quality assurance (QA); (v) analysis and evaluation; (vi, ix) ethics and regulations; and (vii, viii) project coordination and dissemination. To provide a review of current clinical STAR practice in Europe, a comprehensive questionnaire was performed at project start. The STOPSTORM Institutions’ experience in VT catheter ablation (83% ≥ 20 ann.) and stereotactic body radiotherapy (59% > 200 ann.) was adequate, and 84 STAR treatments were performed until project launch, while 8/22 centres already recruited VT patients in national clinical trials. The majority currently base their target definition on mapping during VT (96%) and/or pace mapping (75%), reduced voltage areas (63%), or late ventricular potentials (75%) during sinus rhythm. The majority currently apply a single-fraction dose of 25 Gy while planning techniques and dose prescription methods vary greatly. The current clinical STAR practice in the STOPSTORM consortium highlights potential areas of optimization and harmonization for substrate mapping, target delineation, motion management, dosimetry, and QA, which will be addressed in the various WPs.

1 February 2020 in International Journal of Radiation Oncology, Biology, Physics
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Journal Article
Open access
BMBeata Malachowska
Beata Malachowska
Bartłomiej TomasikBartłomiej Tomasik
Bartłomiej Tomasik
Konrad StawiskiKonrad Stawiski
Konrad Stawiski
SKShilpa Kulkarni
Shilpa Kulkarni
CGChandan Guha
Chandan Guha
WFWojciech Fendler
Wojciech Fendler
MicroRNAs (miRNAs) were hypothesized to be robust and easily measured biomarkers of radiation exposure, which has led to multiple studies in various clinical and experimental scenarios. We sought to identify evolutionary conserved, radiation-induced circulating miRNAs through a multispecies, integrative systematic review and meta-analysis of miRNAs in radiation. The systematic review was registered in the PROSPERO database (ID: 81701). We downloaded a list of studies with the query: (circulating OR plasma OR serum) AND (miRNA or microRNA) AND (radiat* OR radiotherapy OR irradiati*) from MEDLINE (103 studies), EMBASE (364 studies), and Cochrane Database of Systematic Reviews (0 studies). After deleting 116 duplicates, the remaining 351 abstracts were reviewed. Inclusion criteria were experimental study; human, mice, rat or nonhuman primate study; and serum or plasma miRNA expression measured before and after radiation exposure. The screening procedure yielded 62 research studies. After verification, 30 articles contained data on miRNA expression change after irradiation. Thus, we obtained a database of 131 miRNAs from 96 pairwise post-/preirradiation comparisons reporting 2508 fold changes (FCs) of circulating miRNAs. The meta-analysis showed 28 miRNAs with significant radiation-induced change of their expression in the serum. In metaregression analysis, 7 miRNAs-miR-150 (FC = 0.40; 95% confidence interval [CI], 0.35-0.45), miR-29a (FC = 0.87; 95% CI, 0.79-0.96), miR-29b (FC = 0.85; 95% CI, 0.76-0.96), miR-30c (FC = 1.19; 95% CI, 1.09-1.30), miR-200b (FC = 1.34; 95% CI, 1.21-1.48), miR-320a (FC = 1.13; 95% CI, 1.05-1.23), and miR-30a (FC = 1.18; 95% CI, 1.07-1.30)-significantly correlated with either total or fraction dose of radiation. Additionally, miR-150, miR-320a, miR-200b, and miR-30c correlated significantly with time elapsed since irradiation. Circulating miRNAs reflect the impact of ionizing radiation irrespective of the studied species, often in a dose-dependent manner. This makes circulating miRNAs promising biomarkers of radiation exposure.

1 August 2021 in Lung Cancer
Verified
Journal Article
Open access
Bartłomiej TomasikBartłomiej Tomasik
Bartłomiej Tomasik
MBMichał Bieńkowski
Michał Bieńkowski
MBMarcin Braun
Marcin Braun
SPSanjay Popat
Sanjay Popat
RDRafal Dziadziuszko
Rafal Dziadziuszko
Immune checkpoint inhibitors (ICIs) are standard of care in advanced non-small cell lung cancer (NSCLC), however their status in patients with poor performance status (PS) is poorly defined. We aimed to evaluate the efficacy and safety of ICIs in NSCLC patients with PS ≥ 2. We conducted a systematic review and meta-analysis of interventional and observational studies, which reported efficacy and safety data on ICIs in PS ≥ 2 comparing to PS ≤ 1 NSCLC patients. Efficacy endpoints included: Objective Response Rate (ORR), Disease-Control Rate (DCR), Overall Survival (OS), Progression-Free Survival (PFS). Safety endpoint was the incidence of severe (grade≥3) Adverse Events (AE). Random-effects model was applied for meta-analysis. Heterogeneity was assessed using I2. The review is registered on PROSPERO (CRD42020162668). Sixty-seven studies (n = 26,442 patients) were included. In PS ≥ 2 vs. PS ≤ 1 patients, the pooled odds ratios were: for ORR 0.46 (95 %CI: 0.39-0.54, I2:0 %); for DCR 0.39 (95 %CI: 0.33-0.48, I2:50 %) and for AEs 1.12 (95 %CI: 0.84-1.48, I2:39 %). The pooled hazard ratio for PFS was 2.17 (95 %CI: 1.96-2.39, I2:65 %) and for OS was 2.76 (95 %CI: 2.43-3.14, I2:76 %). The safety profile was comparable regardless of the PS status. Patients with impaired PS status are, on average, twice less likely to achieve a response when exposed to ICIs when compared with representative PS ≤ 1 population. For lung cancer patients treated with ICIs, the impaired PS is not only prognostic, but also predictive for response, while the safety profile is not affected. Prospective randomized studies are indispensable to determine whether poor PS patients derive benefit from ICIs.

18 October 2016 in Leukemia & Lymphoma
Verified
Journal Article
Closed access
MBMarcin Braun
Marcin Braun
APAgata Pastorczak
Agata Pastorczak
WFWojciech Fendler
Wojciech Fendler
JMJoanna Madzio
Joanna Madzio
Bartłomiej TomasikBartłomiej Tomasik
Bartłomiej Tomasik
OGon behalf of the Polish Pediatric Leukemia/Lymphoma Study Group
on behalf of the Polish Pediatric Leukemia/Lymphoma Study Group
The inactivation of tumor suppressor genes located within 9p21 locus (CDKN2A, CDKN2B) occurs in up to 30% of children with B-cell precursor acute lymphoblastic leukemia (BCP-ALL), but its independent prognostic significance remains controversial. In order to investigate the prognostic impact of deletions and promoter methylation within 9p21, 641 children with newly diagnosed BCP-ALL using methylation specific multiplex ligation-dependent probe amplification (MS-MLPA) were investigated. A total of 169 (26.4%) microdeletions in 9p21 were detected, of which 71 were homozygous. Patients with CDKN2A homozygous deletions were older at diagnosis (p < .001), more frequently steroid resistant (p = .049), had higher WBC count (p < .001), higher MRD at Day 15 (p = .013) and lower relapse-free survival [p = .028, hazard ratio: 2.28 (95% confidence interval: 1.09–4.76)] than patients without these alterations. CDKN2A homozygous deletions coexisted with IKZF1 and PAX5 deletions (p < .001). In conclusion, CDKN2A homozygous deletions, but not promoter methylation, are associated with poor response to treatment and increased relapse risk of pediatric BCP-ALL.

10 December 2014 in Journal of Molecular Neuroscience
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Journal Article
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MKMagdalena Justyna Kacperska
Magdalena Justyna Kacperska
KJKarol Jastrzebski
Karol Jastrzebski
Bartłomiej TomasikBartłomiej Tomasik
Bartłomiej Tomasik
JWJakub Walenczak
Jakub Walenczak
MKMaria Konarska-Krol
Maria Konarska-Krol
AGAndrzej Glabinski
Andrzej Glabinski
Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS). Four distinct disease courses are known, although approximately 90 % of patients are diagnosed with the relapsing-remitting form (RRMS). The name “multiple sclerosis” pertains to the underlying pathology: the presence of demyelinating plaques in the CNS, in particular in the periventricular region, corpus callosum, cervical spine, and the cerebellum. There are ongoing efforts to discover biomarkers that would allow for an unequivocal diagnosis, assess the activity of inflammatory and neurodegenerative processes, or warn of disease progression. At present, small noncoding RNA particles-microRNA (miRNA, miR) seem to be particularly noteworthy, as they take part in posttranscriptional regulation of expression of various genes. Changes in composition as well as function of miRNA found in body fluids of MS patients are subjects of research, in the hope they prove accurate markers of MS activity. This preliminary study aims to evaluate the expression of selected extracellular microRNA particles (miRNA-let-7a, miRNA-92a, miRNA-684a) in patients experiencing MS relapse and remission, with healthy volunteers serving as a control group and to evaluate the correlation between miRNA expression and selected clinical parameters of those patients. Thirty-seven patients suffering from MS formed two examined groups: 20 patients undergoing relapse and 17 in remission. Thirty healthy volunteers formed the control group. All patients who were subjects to peripheral blood sampling had been hospitalized in the Department of Neurology and Stroke1. Four milliliters of venous whole blood had been collected into EDTA tubes. The basis for the selection of the three particular miRNA investigated in this study (miRNA-let-7a, miRNA-92a, miRNA-684a) was a preliminary bioinformatic analysis of data compiled from several medical databases, including Ovid MEDLINE®, Embase, Cochrane Database of Systematic Reviews (CDSR), miRWalk, and miRBase. The isolation of extracellular microRNA from plasma was carried out using miRNeasy Mini Kit (Qiagen) reagents. The reverse transcription was carried out with TaqMan® MicroRNA Reverse Transcription Kit (Applied Biosystems), as per manufacturers’ instructions. Standard microRNA TaqMan® tests (Applied Biosystems) were used for miRNA quantification. The qPCR were performed on a 7900 HT Fast Real-Time PCR System (Applied Biosystems) and analyzed using Sequence Detection System 2.3 software. In addition, all patients at the Department of Neurology and Stroke undergo a routine complete blood count with differential. The main objective of this study was to evaluate the expression of selected microRNA (has-miR-let-7a, miR-92a, and miR-648a) in the plasma of patients with MS during a relapse as well as in remission and attempt to correlate the acquired data with clinically relevant parameters of the disease. Finding such correlations may potentially lead to the use of miRNA as a biomarker of MS, which could help diagnose the disease and assess its severity and the efficacy of treatment. The difference in the expression of has-miR-let-7a in the remission group and the control group was statistically significant (p = 0.002). Similarly, the expression of miRNA-648a in patients in remission was significantly different from the expression in the control group (p = 0.02). Analysis of the correlation between the expression of miRNA-92a and the severity of the disease as measured by the EDSS scale in patients undergoing relapse showed significant negative linear correlation (r = −0.54, p = 0.01). Higher miR-648a expression correlated with more frequent flare-ups in the joint group of patients in remission and relapse (p = 0.03). This study is one of the few that demonstrate significantly changed expression of selected extracellular miRNA in plasma of MS patients and correlate those findings with clinical parameters. These observations may suggest that some miRNA subsets may be potential biomarkers for MS activity.

1 November 2018 in Translational Research
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Journal Article
Closed access
Bartłomiej TomasikBartłomiej Tomasik
Bartłomiej Tomasik
JCJustyna Chałubińska-Fendler
Justyna Chałubińska-Fendler
DCDipanjan Chowdhury
Dipanjan Chowdhury
WFWojciech Fendler
Wojciech Fendler