Prostate cancer is the most common male cancer in the UK with 35,000 cases diagnosed annually. 35% of these are locally advanced disease. These patients have a high chance of pelvic lymph node involvement and have relatively poor prostate cancer survival rates of 22.5% at 10 years.

One of the standard treatments for these patients is radiotherapy to the prostate. PIVOTAL is a multi-centre phase II non-comparative randomised feasibility trial, in which patients with a high chance of pelvic lymph node involvement are randomised between prostate radiotherapy alone and prostate + pelvic radiotherapy.

Both groups will receive radiotherapy called Intensity Modulated Radiation Therapy (IMRT). This is a relatively new method of shaping radiotherapy treatment beams which allows the tumour to be treated more precisely, whilst avoiding more of the surrounding normal, healthy tissues (particularly the rectum, bladder and bowel). Using IMRT, it is possible to deliver higher doses of radiotherapy to the pelvis than with previous radiotherapy methods - this has been tested in a single hospital, single group setting and levels of side effects (toxicity) were acceptable.

PIVOTAL aims to find out whether toxicity levels at 18 weeks from the start of radiotherapy remain acceptable when treatment is given in multiple cancer centres across the UK. It is randomised to ensure unbiased collection of acute toxicity data and to provide information on patients' willingness to participate in a randomised study. Should the phase II study be successful, the investigators would develop a phase III trial to compare treatment effectiveness (disease control).

Patients who enter PIVOTAL will be followed up for two years from the start of radiotherapy and data relating to toxicity will be collected. They will also be asked to complete patient related symptoms questionnaires. Data related to disease recurrence will then be collected annually from patients' standard hospital visits.

Inclusion Criteria:

1. Histologically confirmed, non-metastatic adenocarcinoma of the prostate, previously untreated (other than by neoadjuvant hormonal treatment)

2. National Collaborative Cancer Network locally advanced disease (T3b± or T4)43 or:

   • Estimated risk of pelvic lymph node involvement ≥30% * and either:

   • Gleason 9 or 10 or
   • Gleason 8 and one other high risk feature (T3± disease or PSA >20) or
   • Gleason 7 and 2 high risk features (T3± disease and PSA ≥30)

3. WHO performance status 0 or 1

4. Normal blood count (Hb > 11g/dl, WBC >4000/mm3, platelets >100,000/mm3)

5. LHRH analogue therapy for 6-9 months duration prior to proposed radiotherapy treatment and PSA < 4ng/ml prior to randomisation.

6. Age ≥ 18 years

7. Patients must be prepared to attend follow up. All patients participating in the Patient Reported Outcomes (PRO) Study must have adequate cognitive ability to complete the PRO questionnaires.

8. Written informed consent

   • T3a disease should be demonstrated convincingly, either clinically or by MRI. T3b disease (seminal vesicle involvement) must be convincingly demonstrated on MR.

     • Risk of pelvic lymph node involvement = (Gleason score - 6) x 10 + 2/3 PSA

Exclusion criteria:

1. Prior pelvic radiotherapy

2. Prior major pelvic surgery (e.g. colectomy, colostomy, cystectomy, prostatectomy)*

3. Radiologically suspicious (short axis diameter ≥1.0cm unless biopsied and negative) or pathologically confirmed lymph node involvement

4. Life expectancy < 5 years

5. Castrate resistant prostate cancer (rising PSA after LHRHa and anti-androgen)

6. Previous active malignancy within the last 5 years other than basal cell carcinoma

7. Co-morbid conditions likely to impact on the decision to treat with radiotherapy (e.g. previous inflammatory bowel disease, previous colo-rectal surgery, significant bladder instability or urinary incontinence)

8. Bilateral hip prosthesis or fixation which would interfere with standard radiation beam configuration

   • Patients who have undergone minor pelvic surgery will be eligible (eg appendicectomy, trans urethral resection of prostate (TURP), exploratory laparoscopy, haemorrhoidectomy, inguinal/femoral hernia repair)