“…Cobalt-60 ( 60 Co) is a radioactive form of cobalt used in radiotherapy for targeting inoperable tumours. 3 The concept of 60 Co radiotherapy was developed in the 1950s by scientists at the University of Saskatchewan in Canada Morrison et al, 1952). Although cobalt therapy has partly been replaced by linear accelerator radiation therapy (the electron beam), which can generate higher energy radiation, cobalt treatment still has a useful role in radiotherapy.…”