When should Pelvic Lymph Node Dissection (PLND) be performed?

When Should Pelvic Lymph Node Dissection (PLND) Be Performed?

PLND should be performed in patients with intermediate-risk prostate cancer when nomogram-predicted probability of lymph node involvement exceeds 2%, and is strongly recommended for all high-risk and locally advanced prostate cancer patients undergoing radical prostatectomy, using an extended dissection technique. 1, 2

Risk-Stratified Approach to PLND

Low-Risk Patients: PLND NOT Recommended

• Patients with PSA <10 ng/mL AND Gleason score ≤6 AND clinical stage <T2b should NOT undergo PLND, as they have less than 10% risk of lymph node metastasis and can be safely excluded when nomogram-predicted probability is <2%. 1, 2

Intermediate-Risk Patients: Selective PLND Based on Nomograms

• Use validated nomograms (such as the Briganti nomogram) to calculate individual risk of lymph node involvement. 3, 2
• Perform PLND when predicted probability exceeds 2%, though this threshold means some patients with positive nodes will be missed (approximately 12% of positive nodes at cost of avoiding 48% of unnecessary dissections). 1
• Engage in shared decision-making discussing the patient's calculated risk, staging benefits, and lymphocele formation risk. 3

High-Risk and Locally Advanced Disease: PLND Strongly Recommended

• All high-risk patients (cT3-4, Gleason 8-10, or PSA >20 ng/mL) undergoing radical prostatectomy should have extended bilateral PLND. 1, 2
• All locally advanced (cT3-4) patients with cN0 disease undergoing surgery require extended PLND. 1

Extended vs. Limited PLND Technique

Why Extended PLND is Mandatory When Performing Dissection

• Extended PLND discovers metastases approximately twice as often as limited obturator-only dissection and provides superior staging accuracy with higher lymph node counts. 1, 4, 2
• Limited obturator fossa dissection alone is inadequate and misses approximately 50% of metastases. 2
• Extended PLND may provide therapeutic benefit by eliminating microscopic metastases, though level 1 evidence is lacking. 1, 5, 6

Anatomic Boundaries for Extended PLND

The extended template includes removal of all node-bearing tissue bounded by:

• External iliac vein (anteriorly)
• Pelvic sidewall (laterally)
• Bladder wall (medially)
• Floor of pelvis (posteriorly)
• Cooper's ligament (distally)
• Internal iliac artery/bifurcation of common iliac artery (proximally) 1, 4, 2

Including the internal iliac packet is critical, as 25% of positive nodes may be found in the internal iliac and common iliac regions, with 75% of these being the exclusive site of metastasis. 7

Contraindications and Important Caveats

Absolute Contraindications

• Do NOT perform PLND if imaging demonstrates gross multiple lymph node involvement (nodes >2 cm diameter), as this typically contraindicates curative surgery. 2

Intraoperative Considerations

• Do NOT perform frozen section analysis of nodes during surgery to decide whether to proceed with or abandon the prostatectomy. 1, 2
• PLND can be performed safely using open, laparoscopic, or robotic techniques with similar complication rates. 1

Relative Contraindications

• PLND may not be feasible or carries increased risk in morbid obesity, previous intraabdominal surgery, or organ transplant recipients. 5
• Extended PLND increases operative time and carries slightly higher risk of lymphocele formation, though other complications and blood loss are not significantly increased. 3

Clinical Pitfalls

The therapeutic benefit of PLND remains controversial. While retrospective data suggest potential survival benefits, a large multi-institutional propensity-matched study found no significant difference in biochemical recurrence-free, metastasis-free, or cancer-specific survival at 120 months between patients who did or did not undergo PLND. 8 However, the staging information remains critical for treatment planning, particularly in high-risk disease where adjuvant therapy decisions depend on nodal status. 3, 2, 6

Contemporary data show increasing adherence to guidelines, with PLND performed in 79.7% of intermediate-risk and 93.5% of high-risk patients by 2016, though disparities persist based on race/ethnicity, socioeconomic status, geographic location, and facility type. 9