In local advanced prostate cancer patients with clinically positive metastatic regional lymph node, the optimal treatment is still unanswered. For these patients, radiotherapy combined with hormonal therapy or hormonal therapy alone are recommended. Recently, the reports from NCCB and SEER data showed that radiotherapy combined with hormonal therapy have better survivals than hormonal therapy alone.

This randomized phase III trial compare hormonal therapy alone with combined hormone with radiotherapy in clinically pelvic lymph node metastatic prostate cancer.

Inclusion Criteria:

• pathologically confirmed prostate cancer within 6 months for study enrollment
• Clincally enlarged pelvic lymph node ((short axis 0.5 cm ≤) in imaging studies (CT, MRI, PET-CT) at diagnosis and partial response or complete remission of enlarged lymph nodes according to RECIST v1.1 after hormonal therapy for 2-3 months 3. age 20 ≤ 4. ECOG performance status 0-1 5. Optimal hematologic profiles within 6 months for study enrollment
• Absolute neutrophil count (ANC) ≥ 1500 cells/mm3
• Platelets ≥ 50,000 cells/mm3
• Hemoglobin ≥ 8.0 g/dl 6. Optimal kidney function within 6 months for study enrollment
• Creatinine < 2.0 ng/dL 7. Optimal liver functions within 6 months for study enrollment
• total bilirubin < 1.5 X maximum normal value
• alanine aminotransferase or aspartate aminotransferase < 2.5 X maximum normal value

Exclusion Criteria:

1. combined with distant metastasis (retroperitoneal lymph node, bone,...)
2. previous history of antiandrogen therapy within 6 months of study enrollment
3. previous history of definitive prostate cancer treatment such as prostatectomy
4. previous history of pelvic radiotherapy
5. previous history of other cancer treatment except for skin cancer and theroid cancer