What is the recommended treatment approach for a patient with localized prostate cancer and nodal involvement when treating the prostate and nodes simultaneously?

Treatment Approach for Prostate Cancer with Nodal Involvement

When treating prostate and pelvic lymph nodes simultaneously, deliver IMRT/VMAT plus IGRT to both the prostate (76-78 Gy) and pelvis in combination with long-term ADT (at least 2 years) and add 2 years of abiraterone for patients with node-positive (cN1M0) disease. 1

Primary Treatment Algorithm for Node-Positive Disease

For cN1M0 patients:

• Deliver external beam radiotherapy using IMRT/VMAT plus IGRT to cover both the prostate and pelvic lymph nodes 1
• Prescribe 76-78 Gy to the prostate using conventional fractionation 1
• Combine with long-term ADT for at least 2 years (24-36 months) 1
• Add abiraterone plus prednisone for 2 years to the radiation and ADT regimen 1

This combination approach (radiation to prostate plus pelvis + ADT + abiraterone) represents the current standard based on the most recent 2024 European guidelines, which provide a strong recommendation for this intensified regimen specifically in node-positive patients 1.

Radiation Dose and Field Considerations

Prostate dose:

• Target 76-78 Gy in conventional fractionation (1.8-2.0 Gy per fraction) 1
• Alternative moderate hypofractionation: 60 Gy/20 fractions in 4 weeks or 70 Gy/28 fractions in 6 weeks 1

Pelvic nodal dose:

• The evidence supports treating pelvic lymph nodes concurrently with the prostate 1
• Research data demonstrates feasibility of dose escalation to pelvic nodes (56 Gy in 2 Gy fractions) concurrent with prostate hypofractionation (70 Gy in 2.5 Gy fractions) using conformal avoidance IMRT techniques 2
• Clinical outcomes show favorable 5-year biochemical failure-free survival (71.4%) and overall survival (89.0%) when pelvic IMRT is combined with long-term ADT in node-positive patients 3

Duration of Androgen Deprivation Therapy

ADT duration is critical for node-positive disease:

• Minimum 2 years of ADT is required 1
• The 2024 EAU guidelines specify "long-term ADT for at least 2 years" as a strong recommendation 1
• Research demonstrates that ADT duration ≥28 months shows significant independent association with improved prostate cancer-specific survival (p=0.02) and overall survival (p=0.001) 3
• The 2018 AUA/ASTRO/SUO guidelines recommend 24-36 months of ADT as adjunct to EBRT for high-risk disease 1

Addition of Abiraterone for Node-Positive Disease

The 2024 guidelines introduce abiraterone as standard for cN1M0 patients:

• Add abiraterone plus prednisone for 2 years to the radiation and ADT regimen 1
• This represents an intensification beyond ADT alone based on recent trial data
• The strong recommendation applies specifically to patients with node-positive (cN1M0) disease 1

Surgical Approach Considerations

For cN0 disease with high-risk features:

• Radical prostatectomy can be offered as part of multimodal therapy (weak recommendation) 1
• Extended pelvic lymph node dissection (ePLND) should be performed if lymph node dissection is undertaken 1
• Do not perform frozen section of nodes during RP to decide whether to proceed with or abandon the procedure 1

For cN1 disease:

• Surgery is generally not the primary approach; radiation-based therapy with systemic intensification is preferred 1

Critical Pitfalls to Avoid

Do not use short-course ADT:

• Short-term ADT (4-6 months) is appropriate only for intermediate-risk disease, not for node-positive or locally advanced disease 1
• Node-positive disease requires minimum 2 years of ADT 1

Do not omit pelvic nodal coverage:

• When nodes are involved or at high risk, the radiation field must encompass the pelvis, not just the prostate 1
• The 2024 guidelines specifically state "IMRT/VMAT plus IGRT to the prostate plus pelvis" for cN1M0 patients 1

Do not omit abiraterone in node-positive disease:

• The 2024 guidelines provide a strong recommendation for adding 2 years of abiraterone to radiation plus ADT specifically for cN1M0 patients 1
• This represents a significant advancement beyond historical ADT-only approaches

Counsel patients about ADT side effects:

• ADT with radiation increases likelihood and severity of adverse effects on sexual function 1
• Systemic side effects include osteopenia/fracture risk and cardiovascular events 4
• These risks must be balanced against the survival benefits, particularly in node-positive disease where treatment intensification is critical 1, 3

Expected Outcomes

With appropriate multimodal therapy (pelvic IMRT + long-term ADT):

• 5-year biochemical failure-free survival: 71.4% 3
• 5-year relapse-free survival: 76.2% 3
• 5-year prostate cancer-specific survival: 94.5% 3
• 5-year overall survival: 89.0% 3

These outcomes demonstrate that node-positive disease, when treated with comprehensive radiation to prostate and pelvis combined with long-term ADT (and now abiraterone per 2024 guidelines), can achieve durable disease control despite unfavorable prognostic factors 3.