Optimizing pelvic lymph node dissection in bladder cancer: obturator focus, pN1 prognosis, and sentinel node...

Area of Science:

• Urology
• Surgical Oncology
• Oncology

Background:

• Optimal pelvic lymph node dissection extent in bladder cancer is crucial.
• Nodal sub-staging and sentinel lymph node biopsy (SLNB) are under investigation.
• Assessing contralateral dissection omission is also a key consideration.

Purpose of the Study:

• To determine the optimal extent of pelvic lymph node dissection for bladder cancer.
• To evaluate the prognostic relevance of nodal sub-staging.
• To assess SLNB feasibility and contralateral dissection omission.

Main Methods:

• Retrospective analysis of 180 patients undergoing radical cystectomy (laparoscopic/robotic).
• Pilot study of SLNB in 30 cases.
• Analysis of lymphatic drainage to define the obturator region.
• Prognostic impact evaluated using Kaplan-Meier and Cox models.

Main Results:

• SLNB showed a 63% detection rate and 1.6% false-negative rate.
• Lymph node metastases were predominantly in the obturator region (87.5% pN1, 100% pN2-3).
• Cancer-specific survival was significantly better for pN1 vs. pN2-3 (61 vs. 7 months).
• pN2-3 was the strongest prognostic factor for cancer-specific survival (HR: 25.4).

Conclusions:

• SLNB had limited utility, but the obturator region is the optimal target for nodal metastasis.
• The obturator region may be therapeutic in pN1 disease, showing limited spread and better prognosis than pN2-3.
• This suggests a more focused nodal dissection strategy.