FACTORS AFFECTING THE SET UP TIME DURING RADIOTHERAPY

Purpose: To assess the factors affecting the set up and treatment time during radiotherapy and use this information to provide guidelines for patients appointment time. Material and Methods: During March 1998, 466 set up times in 104 patients treated at Dokuz Eylül Radiation Oncology Department were recorded and analysed. Diagnosis, treatment machine, number of fields, aim of treatment, performance status of patients, presence of shielding blocks, immobilization devices, wedges, individual shielding trays, number of radiographers, actual treatment time (ATT) and the total treatment time (TTT) from patient entry and exit from the treatment room in minutes was recorded. Setup times (ST) was calculated by substracting ATT from TTT and the relationship to different treatment factors (patients, machine, technical details) were investigated. Results: ST for each field in lineer accelerators is 4.8, where as in Co 60 it was 3.5 minutes. The average ST for different diagnosis and field numbers were as follows: In adjuvant breast irradiation 2, 3, 4, 5 fields 10.8, 9.3, 12.3, 15.2 respectively; lung two fields 10.1; pelvic box 16.3; head and neck 1, 2, 3, 4 fields 6.2, 7.9, 9.6, 18 respectively; two fields brain 8.2 and two fields lymphomas 13.2 minutes. In palliative 3 fields treatment for patients who were mobile, in a wheel chair or brought in a stretcher ST were 8, 14.4 and 24 minutes respectively. Conclusion: To improve and provide realistic appointment times factors affecting ST (patients performance status, number of fields) should be taken in to account. Using this approach a protocol for patient appointment times can be devised.