Flessas Ioannis MD, PhD, MSc, FEBS, FACS is a Mastologist and Doctor of Medicine at the National and Kapodistrian University of Athens Medical School, with private practices in Vrilissia and Ampelokipoi. He studied at the National and Kapodistrian University of Athens Medical School and completed postgraduate studies at the Medical School of Democritus University of Thrace, Alexandroupolis. He specialized in General Surgery at the First Propaedeutic Surgical Clinic of the Medical School of the University of Athens at Hippokration Hospital of Athens and further specialized in Oncoplastic and Reconstructive Breast Surgery, sentinel lymph node technique, intraoperative radiotherapy, and electrochemotherapy at Royal Free Hospital NHS Trust in the United Kingdom. After completing his postgraduate training, he served as a Senior Registrar in the First Surgical Clinic - Breast Department of the General University Hospital "Elena Venizelou." Finally, he is the author of numerous books and scientific articles in the international medical literature and has participated in and attended numerous Greek and international conferences.