Radiotherapy of the Prostate and the Pelvic Lymph Nodes After Neoadjuvant Antihormonal Treatment

Prostate and Whole Pelvis Irradiation With Integrated-boost Intensity-modulated Radiotherapy (IMRT) After Neoadjuvant Antihormonal Treatment - a Phase II Trial

For patients with prostate cancer and a high risk of lymph node involvement or confirmed pelvic lymph node metastases, radiotherapy of the whole pelvis is a treatment option. However, conventional radiotherapy of the pelvis has limited by gastrointestinal and urogenital side effects. The PLATIN trial investigates an intensity-modulated radiotherapy of the pelvic lymphatic drainage that spares small bowel, bladder and rectum. A higher dose is given during each session to the prostate or the prostate bed and to confirmed lymph node metastases. Prior to radiotherapy, two months of neoadjuvant antihormonal treatment are required, and continuation during radiotherapy and for a further two years are strongly recommended.

The PLATIN trial is designed as a prospective, non-randomized, five-arm trial. Arm 1: Definitive radiotherapy of the pelvic lymphatic drainage with integrated boost to the prostate.

Arm 2: As arm 1, with additional boost to macroscopic lymph node metastases. Arm 3: Postoperative radiotherapy of the pelvic lymphatic drainage with integrated boost to the prostate bed.

Arm 4: As arm 3, additional boost to macroscopic lymph node metastases. Arm 5: Patients with previous radiotherapy to the prostate bed. Radiotherapy of the pelvic lymphatic drainage above the previous treatment fields with integrated boost to macroscopic lymph node metastases.

Inclusion Criteria:

• histologically confirmed prostate cancer with Gleason Score
• risk of lymph node involvement >20% (according to Roach Formula), pelvic lymph node metastases in CT/MRI or histologically confirmed lymph node involvement
• Karnofsky Index >/= 70%
• age 18-75 years
• neoadjuvant antihormonal treatment for 2 months, continuation until the end of radiotherapy
• written informed consent

Exclusion Criteria:

• stage IV (distant metastases)
• lymph node metastases outside the pelvis
• rising prostate-specific antigen (PSA) under antihormonal treatment
• severe wound complications after laparatomy
• severe lymph edema of the legs, elephantiasis, postthrombotic syndrome
• decompensated comorbidity of the lungs, heart, metabolic system, hematopoetic system or kidneys, coagulopathy
• history of other malignancy within the last 5 years (except for basal cell carcinoma or squamous carcinoma of the skin)
• previous irradiation of the pelvic lymph nodes
• concurrent participation in a clinical trial that might influence the results of either trial