Ioannis Chatzidakis BSc, MSc, PhD is an Oncologist who maintains a private practice in Marousi. After graduating from the Hellenic-German High School of Athens, he completed his studies at the Department of Biology of the Faculty of Sciences at the National and Kapodistrian University of Athens in 2006. Subsequently, he earned his Interdepartmental Master's Degree in Molecular Medicine with excellence ("Excellent") in 2009. Simultaneously, he was admitted to the Medical School of the University of Thessaly (from which he graduated in 2013). Continuing his postgraduate studies, he completed his doctoral dissertation titled "Molecular Prognostic Markers (predictive - prognostic) in Gastric Cancer" with an "Excellent" grade at the 2nd University Preparatory Clinic of the National and Kapodistrian University of Athens. Since 2022, he has completed his specialty training in Medical Oncology at the 2nd University Preparatory Clinic at the General University Hospital "Attikon" and currently works permanently as a Medical Oncology Consultant at the 4th Oncology Clinic of IASO General Clinic. His specialization includes neoplasms of the gastrointestinal system. Finally, the physician is a member of the Athens Medical Association, the Hellenic Society of Medical Oncologists (HSO), and the European Society For Medical Oncology (ESMO).