A Recursive Partitioning Analysis Demonstrating Risk Subsets for 8-Year Biochemical Relapse After Margin-Positive Radical Prostatectomy Without Adjuvant Hormone or Radiation Therapy.

PURPOSE: The cohort of patients with locally advanced prostate cancer (PC) and positive surgical margin(s) at radical prostatectomy (RP) who would benefit from salvage or adjuvant treatment is unclear. This study examines the risk of prostate-specific antigen (PSA) relapse in a large population of men with PC after margin-positive RP. METHODS AND MATERIALS: Using a multi-institutional database, patients with clinically localized PC who underwent RP between 2002 and 2010 with recorded follow-up PSA were retrospectively selected. Patients were excluded for pathologic seminal vesicle or lymph node involvement, metastatic disease, pre-RP PSA ≥ 30, or adjuvant (nonsalvage) radiation therapy or hormone therapy. The primary endpoint was biochemical relapse free survival (bRFS), where PSA failure was defined as PSA > 0.10 ng/mL and rising, or at salvage intervention. The Kaplan-Meier method was employed for bRFS estimates; recursive partitioning analysis using cumulative or single maximal margin extent (ME) and Gleason grade (GG) at RP was applied to identify variables associated with bRFS. RESULTS: At median follow-up of 105 months, 210 patients with positive margins at RP were eligible for analysis, and 89 had experienced PSA relapse. Median age was 61 years (range, 43-76), and median pre-RP PSA 5.8 ng/mL (1.6-26.0). Recursive partitioning analysis yielded 5 discrete risk groups, with the lowest risk group (GG1, ≤ 2 mm ME) demonstrating a bRFS of 92% at 8 years compared with the highest risk group (GG3-5, ≥ 3 mm ME) of 11%. CONCLUSIONS: This retrospective study suggests that it may be possible to risk-stratify patients undergoing margin-positive RP using commonly acquired clinical and pathologic variables. Patients with low-grade tumors and minimally involved margins have a very low recurrence risk and may be able to forego postprostatectomy radiation. Meanwhile, those with higher grade and greater involvement could benefit from adjuvant or early salvage radiation therapy.

Margin involvement at prostatectomy for clinically localized prostate cancer: does a low-risk group exist?

PURPOSE: To determine whether additional pathology details may provide risk stratification for patients with involved surgical margins at radical prostatectomy (RP). METHODS AND MATERIALS: Eligible patients underwent RP between 2003 and 2010. Patients with preoperative prostate-specific antigen (PSA) ≥20, follow-up <12 months, lymph node or seminal vesicle involvement, or who received radiation therapy or hormone therapy prior to PSA relapse were excluded. Surgical specimens were reviewed by a study pathologist, blinded to outcomes. Survival analysis methods were employed to assess disease control and survival rates, as well as association of patient-, tumor-, and treatment-specific factors for endpoints. RESULTS: Of 355 RP cases, 279 patients were eligible for the present analysis. At a median follow-up of 53 months (range, 16-127), 31/114 (27%) of patients with involved surgical margins experienced PSA relapse, as compared with 7/165 (4%) for negative margins (hazard ratio, 4.997; 95% confidence interval, 2.425-10.296; P < .0001). Detailed pathology review demonstrated associations between PSA relapse and Gleason score at RP, extent of margin involvement (width), capsule penetration, and perineural invasion. Subgroup analysis identified low risk (4%) of 5-year PSA relapse for patients with Gleason ≤6 mm and margin width ≤4 mm (single maximal or cumulative). All subgroups with higher Gleason score or wider margin were associated with >20% risk of PSA relapse at 5 years. CONCLUSIONS: Within the present study, Gleason score, 6 patients with margin width ≤4 mm appear to have low rates of early PSA relapse following RP. Low-grade cases with larger extent of margin involvement or higher risk Gleason score patients with any margin involvement have high rates of early PSA relapse.

Margin details matter: The prognostic significance of pseudocapsule invasion at the site of involved margin in prostatectomy specimens.

BACKGROUND: An involved surgical margin at prostatectomy has long been associated with elevated risk of prostate cancer recurrence; however, not all patients with an involved margin will relapse, and thus details of the involved margin may provide an opportunity for risk subset stratification. The present investigation seeks to determine whether a difference exists in recurrence rates when the margin involvement is at a site of prostate pseudocapsule invasion vs. within the prostate parenchyma proper. METHODS: Patients were retrospectively identified for inclusion by clinically localized disease and prostate-specific antigen (PSA) level of< 30 ng/ml at diagnosis, managed with prostatectomy alone and identified to have involvement of surgical margin(s). Exclusion criteria were: pT3b or pN1 disease, immediate/nonsalvage postoperative radiation or hormone therapy, or insufficient follow-up (<12 mo). Pathology slides were reviewed by a pathologist blinded to outcome, for determination of pseudocapsule invasion at a site of margin involvement. Disease recurrence was defined as PSA level of ≥ 0.2 ng/ml and rising, per contemporary guidelines. Kaplan-Meier method was used for construction of disease control estimate confidence intervals; Cox Proportional Hazards Model was used to compare disease control across groups. RESULTS: Between 2003 and 2010, 155 patients were identified for inclusion in the present study. The median age was 61 years, and all had clinical stage T1 and T2 disease (75% T1c). At diagnosis, the Gleason score was 6, 7, and 8-9 for 103 (66%), 42 (27%), and 10 (6%) patients, respectively, with median PSA level of 5.6 ng/ml (85%≤ 10). For 149 patients with reviewable margin site data, 51 (34%) demonstrated involvement within or beyond the pseudocapsule. At a median follow-up of 68 months (range: 13-137), 62 patients had experienced PSA relapse. The estimated 5-year PSA relapse rates for patients with an involved margin at the site of pseudocapsule invasion vs. prostate parenchyma were 49% vs. 34%, respectively (P = 0.017; hazard ratio = 1.853). CONCLUSIONS: Early PSA relapse rates are high for patients with involved surgical margin(s) without seminal vesicle or node involvement at prostatectomy; however, for patients who are followed without immediate adjuvant therapy, presence of tumor cells at the margin in a site of pseudocapsule invasion or penetration confers a higher risk of recurrence.