Is Unilateral Lymphadenectomy an Option in Selected Patients with Prostate Cancer?

Evidence regarding the relationship between the laterality of lymph node invasion (LNI) and the prostatic lobe affected is limited. Our aim was to review our records of patients with exclusively unilateral localised prostate cancer (PCa) with metastatic LN involvement.

Between 2006 and 2023, after radical prostatectomy and extended pelvic lymphadenectomy at our centre, thirty patients with intermediate-high risk unilateral PCa and pN1 disease were identified. To perform a retrospective study, data were obtained from a prospective collected database approved by the ethical committee at the Valencian Oncology Institute Foundation. Descriptive and comparative statistical analysis was made using software R. The Fisher's Exact test was employed to analyse the categorical variables. In terms of continuous variables, both tumour volume and number of nodes retrieved exhibited normality; Hence Student's T-test was employed. Mann-Whitney U test was utilized for the number of positive nodes.

The median age and prostate specific antigen (PSA) at diagnosis were 66 years old (interquartile range (IQR): 63.3-70.9) and 14.6 ng/mL (IQR: 7.4-21.5), respectively. Median follow-up time was 67 months (IQR: 35.9-92.9). Nineteen patients (63%) had a Gleason score of 7, and the rest had a Gleason score of 8-10. Most patients (73%) had locally advanced disease. Baseline characteristics were comparable between groups (p-value > 0.05). Twenty-two patients (73%) had concordance between the laterality of the PCa lesion and the LNI. All the patients with right prostatic cancer had exclusive ipsilateral LNI.

In our experience, the majority of patients with unilateral PCa had exclusively ipsilateral LNI. However, sparing contralateral LN dissection in unilateral PCa should not be an option. To date, extended pelvic LN dissection remains the gold standard for N-staging and cannot be replaced yet by unilateral pelvic LN dissection until high quality evidence supports this scenario.