Research Interest

Pelvic Lymph Node Irradiation for prostate cancer

The role of pelvic lymph-node irradiation in prostate cancer remains controversial particularly following the recent results of two phase III trials.  Nevertheless it is argued that for ‘high-risk’ disease standard therapy should remain prostate and pelvic radiotherapy with three years of androgen suppression, as this has been the treatment used in phase III trials assessing the duration of hormonal therapy.  In the UK there is some reluctance to using pelvic irradiation due to the risk of acute and late bowel morbidity.

We have completed recruitment (N= 206) to a dose-escalation study using IMRT to deliver doses of 50Gy, 55Gy, and 60Gy to pelvic lymph nodes in sequential cohorts of patients. Toxicity in the first two cohorts is low (Grade 2, 8.8%) and related to bowel volume treated.  Late side-effect data (follow-up 1-4 years) from the 60Gy pelvic dose group (N=124) Shows a Grade 2 toxicity rate of 12% and we will refine dose volume constraints. A further hypofractionated cohort (N=124) using a four to five week schedule completed recruitment during 2010 and recruitment for patients with radiologically positive LN is ongoing.

We have designed and will start a CR-UK supported phase III multicentre trial for patients with high/very high-risk disease randomising between prostate and seminal vesicle or prostate and full pelvic IMRT in 2011. Dose-constraints derived from our phase I/II study results will be used and we will consider hypofractionated schedules depending on results from the CHHiP and hypofractionated phase II pelvic studies.

Schema for dose escalation and hypofractionation in phase 1/2 prostate and pelvic lymph node IMRT study.