Marcus Skribek

Marcus Skribek

PhD Student

Primary research focus is on improving the efficacy of immune checkpoint inhibitors through translational research in patients with advanced non-small cell lung cancer.

About me

As a dedicated clinician and researcher, I hold a dual role:

  • Serving as a Resident Oncologist at Theme Cancer, Karolinska University Hospital, I am deeply committed to providing compassionate and cutting-edge care to individuals battling cancer.

  • Concurrently, I am pursuing my PhD at the Department of Oncology-Pathology, Karolinska Institutet, delving into the complex realm of non-small cell lung cancer (NSCLC) treatment. Specifically, I focus on the remarkable potential of immune checkpoint inhibitors (ICIs) in eliciting substantial responses and extending survival in select NSCLC patients. Yet, the persistent challenge of treatment resistance poses a significant hurdle to prolonged patient survival.

My research endeavors center around the identification of crucial clinical factors and biomarkers that dictate treatment response and resistance. By unraveling these key insights, I aspire to not only enhance survival rates but also elevate the overall quality of life for this patient demographic. Furthermore, these discoveries may pave the way for groundbreaking therapeutic approaches, ultimately reshaping the landscape of NSCLC treatment.


  • International Association for the Study of Lung Cancer (IASLC)
  • Swedish Society of Oncology (SOF)
  • European Society for Medical Oncology (ESMO)
  • American Society of Clinical Oncology (ASCO)


  • Medical Aid & Teaching in Ghana

Research description

In recent years, there has been a noticeable decline in lung cancer fatality rates, particularly in advanced non-small cell lung cancer (NSCLC). This shift is attributed to significant progress in understanding the molecular underpinnings of cancer, leading to the emergence of innovative therapies, including immune checkpoint inhibitors (ICIs). ICIs have achieved unprecedented five-year overall survival rates in NSCLC, a milestone previously unimaginable. However, lung cancer remains the leading cause of cancer-related mortality across genders, imposing a substantial societal and economic burden.

While ICIs have revolutionized treatment, they have also introduced a new frontier of treatment toxicities, impacting patients' quality of life. The mechanisms behind these immune-related adverse events (irAEs) remain elusive, leaving researchers puzzled about why some individuals exhibit heightened sensitivity to such toxicities.

Our previous studies have explored clinical factors relevant to ICIs. Notably, concurrent corticosteroid administration during ICI therapy can adversely affect overall survival. Our findings emphasize that the underlying indication for corticosteroid use is pivotal; patients with more advanced cancer face poorer outcomes, irrespective of corticosteroid administration. Conversely, those receiving corticosteroids due to irAEs appear to exhibit improved survival, underscoring the importance of timely irAE management without undue concern for ICI efficacy.

Additionally, the presence of brain metastases (BM) in NSCLC patients serves as an adverse prognostic factor. The debate surrounding the use of ICIs in this context persists, given limited data and concerns over ICI effectiveness in the distinct central nervous system tumor microenvironment.

While ICIs have undeniably transformed advanced NSCLC into a manageable chronic condition, durable remissions are still experienced by only a fraction of patients. Currently, the biomarker which has persistently proven to be the most clinically robust with the highest predictive value is programmed death-ligand 1 (PD-L1). Exploratory analyses of increasing PD-L1 expression have been correlated with incremental improvements in outcome measures. However, the role of PD-L1 as a predictive biomarker remains debated, as cases with low or negative PD-L1 expression have demonstrated clinical response to ICIs. This further underscores that PD-L1 is an imperfect biomarker and needs to be further explored.

Our research strives to advance patient-tailored ICIs and advocates for a comprehensive approach to advanced NSCLC management. By deepening our understanding of the tumor microenvironment and clinical factors associated with ICIs, our study aims to unearth more robust prognostic and predictive biomarkers. This endeavor seeks to bridge current knowledge gaps, ultimately translating into clinically significant improvements in patient survival and quality of life, with direct societal and economic implications.

Therefore, there is a clear need to further investigate the effects of ICIs at both the molecular level as well as in the clinical setting to improve our understanding in this area.

Teaching portfolio

  • Seminar supervisor in cancer biology (i.e. targeted therapy), courses in oncology
  • Clinical supervisor for medical students
  • Junior supervisor in Ekman's research group
  • Responsible for organizing educational seminars for residents in oncology
  • Created local guidelines for the use of hematopoietic stimulating factors in cancer care.


Doctor of Philosophy (Ph.D.), Karolinska Institutet - Ongoing

  • Research School for Clinicians in Epidemiology

Doctor of Medicine (M.D.), Semmelweis University, Faculty of Medicine

Elective clinical placements (2013-2018):

  • Karolinska University Hospital, Stockholm - Medical Oncology
  • Prince of Wales Hospital, University of New South Wales, Sydney - Surgical Oncology, Vascular Surgery, and Traumatology
  • The Royal Infirmary, University of Edinburgh, Edinburgh - Orthopaedic Surgery
  • Semmelweis University, Budapest - Endocrinology, Obstetrics & Gynecology

Academic honours, awards and prizes

Peer reviewer for several eminent international scientific journals.


  • Cum Laude in Doctor of Medicine (M.D.)
  • Award for Outstanding Presentation
  • Academic Award
  • High Honor Roll for Outstanding Performance
  • Duke of Edinburgh's Award


  • Research grant from one of Sweden's most prestigious foundations, Radiumhemmets Forskningsfonder