Thomson qualified from the University of Sydney in 1928 and worked at Sydney Hospital as resident medical officer 1928-29 and surgical registrar 1929-30. He was in England during 1932-33 when he obtained the Membership of the Royal College of Physicians of London and the Fellowship of the Royal College of Surgeons of England. He returned to Australia and practised for two or three years at Mosman, Sydney. He came back to England about 1938 and practised at Esher, Surrey and was for a time surgeon to Salisbury Infirmary. He later returned again to Australia and died there shortly before May 1968, in his early sixties.