Therapeutic value of lymph node dissection at radical prostatectomy: a population-based case-cohort study

Area of Science:

• Urology
• Oncology
• Surgical Pathology

Background:

• Pelvic lymphadenectomy (PLND) is a standard procedure in prostate cancer staging and treatment.
• The optimal number of lymph nodes to remove for maximal therapeutic benefit remains under investigation, particularly for low to intermediate-risk prostate cancer.

Purpose of the Study:

• To investigate the association between the number of lymph nodes removed during pelvic lymphadenectomy and the risk of prostate cancer death.
• To specifically evaluate this association in patients with low to intermediate-risk prostate cancer.

Main Methods:

• A population-based case-cohort study utilizing data from 281 patients who underwent prostatectomy and PLND, alongside 41 cases who died of prostate cancer within 10 years.
• Cox proportional hazards regression analysis was employed to assess the impact of the number of lymph nodes removed, adjusting for confounders like age, PSA, T category, Gleason score, and hormonal therapy.
• Secondary analysis stratified results by pathological nodal status.

Main Results:

• No statistically significant association was found between increased lymph node removal and reduced prostate cancer mortality in the overall cohort (HR: 0.97).
• While not statistically significant, removing 4 or more, or 10 or more lymph nodes suggested a 25% risk reduction.
• In node-negative patients, increased lymph node removal showed a trend towards benefit (HR: 0.95), whereas node-positive patients showed a potential slight increase in risk (HR: 1.10).

Conclusions:

• Pelvic lymph node dissection may offer a therapeutic benefit in node-negative prostate cancer patients.
• Further research is warranted to elucidate the biological mechanisms underlying the potential therapeutic benefits of PLND, especially in lower-risk patients with histologically negative lymph nodes.