Target volume delineation guidelines in bladder cancer

Abstract

The use of radiotherapy (RT) in the treatment of bladder cancer has been decreasing through the years. There is no role of RT in carcinoma in situ and Ta and Tl tumors. However, irradiation may have a role in high-grade or recurrent T1 lesions. There is no prospective randomized trial comparing surgery with RT in muscle-invasive bladder cancer. In T2-T4a disease without lymph node (LN) involvement, RT can be combined with concurrent chemotherapy in medically fit patients. However, there is no rationale of RT in patients with LN or distant metastasis except for palliative reasons. The gross tumor volume (GTV), clinical target volume (CTV), planning target volume (PTV), and organs at risk (OAR) should be delineated separately in each slice based on the recommendations in the International Commission on Radiation Units and Measurements (ICRU) reports 50 and 62. The only delineation guideline for the RT in bladder cancer has been reported by the Australian and New Zealand Faculty of Radiation Oncology Genito-Urinary Group.