MP51-02: Prospective study to evaluate the prognostic value of nodal disease in prostate cancer?

Javier Pérez Ardavín*, Manuel Martínez-Sarmiento, Juan José Monserrat-Monfort, Jose Vicente Sanchez-Gonzalez, Victor Vera-Pinto, Valencia, Spain, Pilar Bello-Arqués, València, Spain, Francisco Boronat-Tormo, César David Vera Donoso, Valencia, Spain

Introduction: Currently, for a correct nodal staging, an extended pelvic lymph node dissection (ePLND) is required, because diagnostic imaging techniques do not offer enough sensitivity or specificity for lymph nodes (LNs) staging. The objective was to carry out a prospective study to evaluate the prognostic value of the sentinel node (SN) technique with 99mTcnanocolloid.

Methods: We had conducted a prospective study between January 2013 and May 2020. We included patients with a Briganti nomogram-assessed risk equal to or higher to 5% (Briganti nomogram 2012), who were candidates to perform a radical prostatectomy. To evaluate de prognosis we had analyzed the PSA every 3 months in the first year and every 6 months from the second year. To assess which parameters were associated with the presence or absence of biochemical recurrence we had performed a univariate analysis, a logistic regression, and a Kaplan-Meier test. All of the patients signed the informed consent form and the study protocol was approved by the ethical committee.

Results: We had included a total of 106 patients, in 4 out of the total the radiotracer did not migrate. Only ISUP, risk group, positive lymph nodes, and positive margins showed statistical differences (p < 0.05). On evaluating which factors have determined the biochemical recurrence, we observe that those most determinant are the positive nodes (OR 3.893, CI95% 1.133±13.38) (p=0,031), the positive margins (OR 2.925, CI95% 0.46±18.329) (p=0,252) and the ISUP grade of the anatomopathological sample (OR 1.405, CI95% 0.832±2.372) (p=0,203).
When we had evaluated the biochemical recurrence in the short term using the Kaplan-Meier test, we observed that patients without nodal affection did not reach the average of the monitory progress, however, the mean was 73 months (CI95%; 66.25 –79.8). In those with lymphatic affection, the average was 32 months (CI95%; 23.4 – 41.36) which is statistically significant (p < 0.001). However, if we divide it into different groups depending on the nodal load, patients with a positive LN had a mean time to biochemical recurrence of 36 months (95% CI: 24.18 - 48.08) compared to patients with 2 or more GLs with a mean of 28.28 months (15.86 - 40, 72), being these differences statistically significant (p <0.001).

Conclusions: In our series, positive LN invasion was the main factor to have a biochemical recurrence. Furthermore, the nodal load was shown as a good variable to know the possibility of biochemical recurrence in the short term. Maybe these patients, whose biochemical recurrence was too short, could require adjuvant treatments.

Source of Funding: none