A graduate of the University of Melbourne, Dr Sikaris trained at the Royal Melbourne, Queen Victoria, and Prince Henry's Heidelberg Repatriation Hospitals. He obtained fellowships from the Royal College of Pathologists of Australasia and the Australasian Association of Clinical Biochemists in 1992 and 1997 respectively.

Dr Sikaris was Director of Chemical Pathology at St Vincent's Hospital in Melbourne between 1993 and 1996. A NATA-accredited laboratory assessor, Dr Sikaris specialises in Prostate Specific Antigen, cholesterol and quality assurance and is currently chair of the International Federation of Clinical Chemistry Committee on Analytical Quality. His expertise is highly sought and he has presented extensively at national and international symposiums.