1987 - 1997  Studium der Humanmedizin, Heinrich-Heine Universität Düsseldorf
 
1997 Staatsexamen
 
1999 Approbation

1997 - 1998  AIP, Rheinische Kliniken Essen, Klinik für Psychiatrie, Universitätsklinikum Essen
 
1999 - 2002  Assistenzarzt, Westf. Zentrum für Psychiatrie, Psychotherapie und Psychosomatik Dortmund, Universitätsklinikum Ruhr-Universität Bochum
 
2003  Assistenzart der Neurologischen Universitätsklinik, Knappschaftskrankenhaus Bochum
 
2004  Facharzt für Psychiatrie und Psychotherapie
 
2004  Abgeschlossene Ausbildung zum Systemischen Familentherapeuten, Institut für Familientherapie Weinheim
 
2007  Facharzt für Neurologie
 
Seit 2010  Oberarzt der Neurologischen Universitätsklinik, Knappschaft Kliniken Universitätsklinikum Bochum

Seidel S, Margold M, Kowalski T, Baraniskin A, Schroers R, Korfel A, Thiel E, Weller M, Martus P, Schlegel U. Patients with primary central nervous system lymphoma not eligible for clinical trials: prognostic factors, treatment and outcome. Cancers (Basel) 2021:13: 2934

Margold M, Seidel S, Kowalski T, Ladigan S, Baraniskin A, Schroers R, Frey AV, Schmidt-Wolf IGH, Herrlinger U, Korferl A, Schlegel U. The value of bone marrow biopsy for staging of patients with primary CNS lymphoma. Neuro Oncol. 2021;noab 109. doi: 10.1093/neuonc/noab106. Online ehead of print

Pertz M, Kowalski T, Schlegel U, Thoma P. Mental time travel in patients "cured" from primary central nervous system lymphoma. Journal of clinical and experimental Neuropsychology, 1 - 12. 2021;Advanced online publication. doi.org/10.1080/13803395.2021.1912299

Anton S, Margold M, Kowalski T, Miller D, Schmieder K, Schlegel U, Seidel S. Complications of intracerebroventricular chemotherapy via subgaleal reservoir in primary central nervous system lymphoma: a single-institution experience on 1247 installations in 94 consecutive patients. Hematol Oncol. 2020;PMID:33316084

Pertz M, Kowalski T, Thoma P, Schlegel U. What is on your mind? Impaired social cognition in primary central nervous system lymphoma despite ongoing complete remission. Cancers (Basel) 2021;13: 943

Seidel S, Kowalski T, Margold M, Baraniskin A, Schroers R, Martus P, Schlegel U. HDMTX-based polychemotherapy including intraventricular therapy in elderly patients with primaryCNS lymphoma: A single center series. 2020 Therapeutic Advances in Neurological Disorders; accepted 26.07.2020.

Waldera-Lupa DM, Poschmann G, Kirchgaessler N, Etemad-Parishanzadeh O, Baberg F, Brocksieper M, Seidel S, Kowalski T, Brunn A, Haghikia A, Gold R, Stefanski A, Deckert M, Schlegel U, Stühler K. A multiplex assay for the stratification of patients with primary Central Nervous System Lymphoma using targeted mass spectrometry. Cancers (Basel) 2020;12: E1732,doi:

Wiemann G, Pertz M, Kowalski T, Seidel S, Schlegel U, Thoma P. Complete response to therapy: why do primary central nervous system lymphoma patients not return to work? Journal of Neuro-Oncology 2020;Accepted

Seidel S, Korfel A, Kowalski T, Margold M, Ismail F, Schroers R, Baraniskin A, Pels H, Martus P, Schlegel U. HDMTX-based induction therapy followed by consolidation with conventional systemic chemotherapy and intraventricular therapy (modified Bonn protocol) in primary CNS lymphoma: a monocentric retrospective analysis. Neurol. Res. Pract. 2019;1:17

Herrlinger U, Tzaridis T, Mack F, Steinbach JP, Schlegel U, Sabel M, Hau P, Kortmann RD, Krex D, Grauer O, Goldbrunner R, Schnell O, Bähr O, Uhl M, Seidel C, Tabatabai G, Kowalski T, Ringel F, Schmidt-Graf F, Suchorska B, Brehmer S, Weyenbrock A, Renovanz M, Bullinger L, Galldiks N, Vajkoczy P, Misch M, Vatter H, Stuplich M, Schäfer N, Kebir S, Weller J, Schaub C, Stummer W, Tonn JC, Simon M, Keil VC, Nelles M, Urbach H, Coenen M, Wick W, Weller M, Fimmers R, Schmid M, Hattingen E, Pietsch T, Coch C, Glas M, Neurooncology Working Group of the Cancer Society. Lomustine-temozolomide combination therapy versus standard temozolomide therapy in patients with newly diagnosed glioblastoma with methylated MGMT promotor (CeTeG/NOA 09): a randomised,open-label, phase 3 trial. Lancet 2019;393: 678 - 688

Waldera-Lupa DM, Etemad-Parishanzadeh O, Brocksieper M, Kirchgaessler N, Seidel S, Kowalski T, Montesinos-Rongen M, Deckert M, Schlegel U, Stühler K. Proteomic changes in cerebrospinal fluid from primary central nervous system lymphoma patients are associated with protein ectodomain shedding. Oncotarget 2017;8

Popkirov S, Kowalski T, Schlegel U, Skodda S. Immunoglobulin-G4-related hypertrophic pachymeningitis with antineutrophil cytoplasmatic antibodies effectively treated with rituximab. J Clin Neurosci. 2015;22: 1038 - 1040

Kuhnhenn J, Kowalski T., Steenken S, Ostermann K, Schlegel U. Procarbazine, carmustine, and vincristine (PBV) for chemotherapy pre-treated patients with recurrent glioblastoma: a single-institution analysis. J Neurooncol.2012; 109: 433 - 438

Kowalski T, Maier C, Reinacher-Schick A, Schlegel U. Painful hyperexcitability syndrome with oxaliplatin containing chemotherapy. Clinical features, pathophysiology and therapeutic options. Schmerz 2008;22: 16 - 23

Bonnert U, Banger M, Leweke FM, Maschke M, Kowalski T, Gastpar M. Treatment of alcohol withdrawal syndrome with gabapentin. Pharmacopsychiatry 1999;32: 107 - 109