Presentation Authors: Shintaro Narita*, Yoshinori Matsuda, Atsushi Koizumi, Akita, Japan, Teppei Okubo, Koji Mitsuzuka, Sendai, Japan, Shingo Hatakeyama, Takuya Koie, Hirosaki, Japan, Sadafumi Kawamura, Tatsuo Tochigi, Natori, Japan, Chikara Ohyama, Hirosaki, Japan, Yoichi Arai, Sendai, Japan, Tomonori Habuchi, Akita, Japan
Introduction: The impact of a positive surgical margin (PSM) considering the nerve-sparing status on clinical outcomes in patients with prostate cancer treated with radical prostatectomy (RP) is largely unknown. Here we assessed the relationship between PSM, the nerve-sparing status, and biochemical recurrence (BCR) based on a multicenter RP database.
Methods: We retrospectively reviewed 1135 patients who underwent RP between 2010 and 2014 among the Michinoku Japan Urological Cancer Study Group. We excluded 10 patients because of missing PSM data. The PSM status was determined according to the International Society of Urological Pathology Consensus Conference on Handling and Staging of RP Specimens. We statistically assessed the impact of PSM location and nerve-sparing sites on BCR.
Results: PSM rates were 18.7% in the 1125 patients studied, 9.6% in patients with â‰¤pT2, and 40.1% in patients with â‰¥pT3. Among all patients, 9.1% experienced BCR during a median follow-up of 44 months. PSM was significantly associated with BCR-free survival in patients with â‰¤pT2 (p < 0.001), whereas it was not associated with BCR-free survival in patients with â‰¥pT3 (p = 0.257). In all patients, nerve sparing was significantly associated with PSM after adjusting for age and clinical risk factors. However, the patients who received uni- and bilateral nerve sparing had a BCR-free survival comparable with those who did not receive nerve sparing. Regarding the site of PSM, the apex (56.7%) and the anterior (51.4%) were the most common sites in the horizontal and axial planes, respectively. Multivariate analysis by adjusting for age and clinical factors showed that PSM at the anterior-apex was not a risk factor for BCR (HR 0.937, p = 0.840), although PSM at any location was an independent risk factor for BCR (HR 2.376, p < 0.001). Patients with PSM at the non-anterior-apex on the nerve-sparing side had lower BCR-free survival than those with a negative surgical margin (p = 0.006), whereas those with PSM at the anterior-apex on the nerve-sparing side had a BCR-free comparable with those with a negative surgical margin (p = 0.598).
Conclusions: PSM affects BCR differentially based on the nerve-sparing status and its location. During nerve-sparing RP, two different strategies with a careful dissection to avoid PSM at the non-anterior-apex and an aggressive dissection without hesitating PSM at the anterior-apex may be considered.