SBRT is a new technology in radiation oncology which is faster and shorter treatment approach when compared to IMRT. SBRT can finish the treatment in 1 - 2 week while IMRT takes 7-8 weeks. A study published in JCO march 2014 issue revealed that patients treated with SBRT had more urinary symptoms compared to IMRT. This was the retrospective study by Dr Yu and his colleagues. The cohort consisted of 1335 patients treated with SBRT and 2670 matched patients treated with IMRT. At 6 month and 12 month genitourinary complications were more in SBRT group, while gastrointestinal toxicity was also more in SBRT group at 6 month but no difference at 12 month. After one year also this difference was persistent in terms of genitourinary complications.
SBRT is technically a very complex process and there might be a learning curve to its optimal use. This may be one of the reason for increase in toxicity. The other reason may be the limitations of this study as this was non randomise and retrospective study.