Over the years HDR brachytherapy is replacing conventional LDR treatment which is evident by the reduction in manufacturing of LDR equipment. The decision to select HDR brachytherapy is also influenced by the versatility of the machine. Although cervical cancer is the most common tumour site treated by HDR in developing countries, it is also possible to treat a wide variety of other tumours such as lung, oesophagus, breast, bile duct, endometrium, nasopharynx, prostate, rectum, head and neck and soft tissue tumours.
192Ir is the most commonly used radio-isotope for HDR brachytherapy. However, a major drawback is the short half-life of 74 days which requires a frequent source change every 3 to 4 months. Recently, machines using miniaturized. 60Co source are also available with a half-life of 5.26 years, which is a major advantage, but experience with this HDR system is still limited.
The initial cost of HDR equipment is high. However, the capacity to treat more patients with HDR with little incremental cost, coupled with the versatility of the HDR machine, can overcome the higher cost and demonstrate an economic advantage.