Intermittent Versus Continuous Androgen Deprivation Therapy for Biochemical Progression After Primary Therapy in Hormone-Sensitive Nonmetastatic Prostate Cancer: Comparative Analysis in Terms of CRPC-M0 Progression

INTRODUCTION

To analyze whether the use of an intermittent (IAD) versus continuous (CAD) androgen deprivation therapy for the treatment of biochemical progression after primary treatments in prostate cancer can influence the development of nonmetastatic castration resistant prostate cancer (CRPC-M0).

PATIENTS

170 male patients with an histologically confirmed diagnosis of PC, presenting a biochemical progression after primary treatments (82 after radical prostatectomy and 88 after external radiation therapy), nonmetastatic at imaging were considered for continuous (85 cases) or intermittent (85 cases) administration of androgen deprivation therapy.

METHODS

we retrospectively collect all data regarding histological diagnosis, primary treatment, imaging for M0-M1 staging, PSA at progression, time to biochemical progression from primary therapy, ADT used, IAD cycles, so to compare in 2 groups (IAD vs. CAD) time for progression from the beginning of ADT treatment and type of progression in terms of CRPC-M0 versus CRPC-M1 cases.

RESULTS

no significant (P= .4955) difference in the whole CRPC progression was found between IAD (25.8%) and CAD (30.5%) treatment at a mean of 32.7 ± 7.02 months and 35.6 ± 13.1 months respectively (P= .0738). Mean PSA at CRPC development was significantly higher in the IAD group (5.16 ± 0.68 ng/mL) than in the CAD group (3.1 ± 0.7 ng/mL) (P < .001). In all cases, imaging to detect M status at CRPC development was PET TC scan. At univariate analysis CAD administration significantly increases the RR for CRPC-M0 progression (RR 3.48; 95%CI 1.66-7.29; P = .01) when compared to the IAD administration, and this effect at multivariate analysis remained significant and independent to the other variables (RR 2.34, 95%CI 1.52-5.33; P = .03).

CONCLUSIONS

in our population with biochemical progression after primary treatment for PC, the intermittent administration of ADT significantly reduces the risk to develop CRPC-M0 disease when compared to a continuous administration of ADT, whereas no difference between the 2 strategies in terms of CRPC-M1 progression exists.

Dose-intensified Versus Conventional-dose Salvage Radiotherapy for Biochemically Recurrent Prostate Cancer After Prostatectomy: The SAKK 09/10 Randomized Phase 3 Trial

BACKGROUND

Salvage radiotherapy (SRT) is utilized for biochemical progression of prostate cancer after radical prostatectomy (RP).

OBJECTIVE

To report the outcomes of the SAKK 09/10 trial comparing conventional and dose-intensified SRT.

DESIGN, SETTING, AND PARTICIPANTS

SAKK 09/10 was a randomized, multicenter, phase 3 trial that recruited men with biochemical progression after RP.

INTERVENTION

Patients were randomly assigned to conventional-dose (64 Gy) or dose-intensified SRT (70 Gy) to the prostate bed without hormonal therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was freedom from biochemical progression (FFBP). Secondary endpoints included clinical progression-free survival (PFS), time to hormonal treatment, overall survival (OS), acute and late toxicity (Common Terminology Criteria for Adverse Events v4.0), and quality of life (QoL).

RESULTS AND LIMITATIONS

Between February 2011 and April 2014, 350 patients were randomly assigned to 64 Gy (n = 175) or 70 Gy (n = 175). Median prostate-specific antigen at randomization was 0.3 ng/ml. After median follow-up of 6.2 yr, the median FFBP was 8.2 yr in the 64 Gy arm and 7.6 in the 70 Gy arm (log-rank p = 0.4), with a hazard ratio of 1.14 (95% confidence interval 0.82-1.60). The 6-year FFBP rates were 62% and 61%, respectively. No significant differences in clinical PFS, time to hormonal treatment, or OS were observed. Late grade 2 and 3 genitourinary toxicity was observed in 35 (21%) and 13 (7.9%) patients in the 64 Gy arm, and 46 (26%) and seven (4%) in the 70 Gy arm, respectively (p = 0.8). Late grade 2 and 3 gastrointestinal toxicity was observed in 12 (7.3%) and seven patients (4.2%) in the 64 Gy arm, and 35 (20%) and four (2.3%) in the 70 Gy arm, respectively (p = 0.009). There were no significant differences in QoL.

CONCLUSIONS

Conventional-dose SRT to the prostate bed is sufficient in patients with early biochemical progression of prostate cancer after RP.

PATIENT SUMMARY

The optimal radiation therapy dose for patients who have increased tumor markers after surgery for prostate cancer is unclear. We found that administering a higher dose only increased the gastrointestinal side effects without providing any benefits to the patient. This clinical trial is registered on ClinicalTrials.gov as NCT01272050.

Efficacy of repeated PSMA PET-directed radiotherapy for oligorecurrent prostate cancer after initial curative therapy

PURPOSE

To assess the outcome of prostate cancer (PCa) patients diagnosed with oligorecurrent disease and treated with a first and a second PSMA (prostate-specific membrane antigen ligand) PET(positron-emission tomography)-directed radiotherapy (RT).

PATIENTS AND METHODS

Thirty-two patients with oligorecurrent relapse after curative therapy received a first PSMA PET-directed RT of all metastases. After biochemical progression, all patients received a second PSMA PET-directed RT of all metastases. The main outcome parameters were biochemical progression-free survival (bPFS) and androgen deprivation therapy-free survival (ADT-FS). The intervals of BPFS were analyzed separately as follows: the interval from the last day of PSMA PET-directed RT to the first biochemical progression was defined as bPFS_1 and the interval from second PSMA PET-directed RT to further biochemical progression was defined as bPFS_2.

RESULTS

The median follow-up duration was 39.5 months (18-60). One out of 32 (3.1%) patients died after 47 months of progressive metastatic prostate cancer (mPCa). All patients showed biochemical responses after the first PSMA PET-directed RT and the median prostate-specific antigen (PSA) level before RT was 1.70 ng/mL (0.2-3.8), which decreased significantly to a median PSA nadir level of 0.39 ng/mL (range <0.07-3.8; p = 0.004). The median PSA level at biochemical progression after the first PSMA PET-directed RT was 2.9 ng/mL (range 0.12-12.80; p = 0.24). Furthermore, the PSA level after the second PSMA PET-directed RT at the last follow-up (0.52 ng/mL, range <0.07-154.0) was not significantly different (p = 0.36) from the median PSA level (1.70 ng/mL, range 0.2-3.8) before the first PSMA PET-directed RT. The median bPFS_1 was 16.0 months after the first PSMA PET-directed RT (95% CI 11.9-19.2) and the median bPFS_2 was significantly shorter at 8.0 months (95% CI 6.3-17.7) after the second PSMA PET-directed RT (p = 0.03; 95% CI 1.9-8.3). Multivariate analysis revealed no significant parameter for bPFS_1, whereas extrapelvic disease was the only significant parameter (p = 0.02, OR 2.3; 95% CI 0.81-4.19) in multivariate analysis for bPFS_2. The median ADT-FS was 31.0 months (95% CI 20.1-41.8) and multivariate analysis showed that patients with bone metastases, compared to patients with only lymph node metastases at first PSMA PET-directed RT, had a significantly higher chance (p = 0.007, OR 4.51; 95% CI 1.8-13.47) of needing ADT at the last follow-up visit.

CONCLUSION

If patients are followed up closely, including PSMA PET scans, a second PSMA PET-directed RT represents a viable treatment option for well-informed and well-selected patients.

Identification of curable high-risk prostate cancer using radical prostatectomy alone: who are the good candidates for undergoing radical prostatectomy among patients with high-risk prostate cancer?

Background

Currently, there is no consensus regarding which patients with high-risk prostate cancer (PCa) would benefit the most by radical prostatectomy (RP). We aimed to identify patients with high-risk PCa who are treatable by RP alone.

Methods

We retrospectively reviewed data on 315 patients with D’Amico high-risk PCa who were treated using RP without neoadjuvant or adjuvant therapy at the institutions of the Yamaguchi Uro-Oncology Group between 2009 and 2013. The primary endpoint was biochemical progression-free survival (bPFS) after RP. Risk factors for biochemical progression were extracted using the Cox proportional hazard model. We stratified the patients with high-risk PCa into 3 subgroups based on bPFS after RP using the risk factors.

Results

At a median follow-up of 49.9 months, biochemical progression was observed in 20.5% of the patients. The 2- and 5-year bPFS after RP were 89.4 and 70.0%, respectively. On multivariate analysis, Gleason score (GS) at biopsy (≥ 8, HR 1.92, p < 0.05) and % positive core (≥ 30%, HR 2.85, p < 0.005) were independent predictors of biochemical progression. Patients were stratified into favorable- (0 risk factor; 117 patients), intermediate- (1 risk factor; 127 patients), and poor- (2 risk factors; 57 patients) risk groups, based on the number of predictive factors. On the Cox proportional hazard model, this risk classification model could significantly predict biochemical progression after RP (favorable-risk, HR 1.0; intermediate-risk, HR 2.26; high-risk, HR 5.03; p < 0.0001).

Conclusion

The risk of biochemical progression of high-risk PCa after RP could be stratified by GS at biopsy (≥ 8) and % positive core (≥ 30%).

Prognostic value of seminal vesicle involvement due to prostate cancer in radical prostatectomy specimens

OBJECTIVE

To study the influence, in terms of prognosis, of the finding of seminal vesicle involvement in patients with prostate adenocarcinoma treated with radical prostatectomy.

MATERIAL AND METHOD

We reviewed a series of patients with seminal vesicle involvement with clinically localized prostate adenocarcinoma who underwent radical prostatectomy between 1989 and 2009, focusing on their clinical-pathological characteristics, biochemical progression-free survival (BPFS) and specific survival (SS). We assessed the variables that influenced BPFS and designed a risk model.

RESULTS

A total of 127 out of 1,132 patients who underwent surgery (11%) presented seminal vesicle invasion (i.e., pT3b). In the multivariate study of the entire series (Cox model), pT3b affects the BPFS (HR: 2; 95% CI: 1.4-3.3; P=.001). Other influential factors were the affected borders, initial prostate-specific antigen levels, pathological Gleason score and the presence of palpated tumor. The pT3b tumors have poorer clinical-pathological variables when compared with pT2 and pT3a tumors. Sixty-five percent of the patients evidenced biochemical progression. The BPFS was significantly poorer for pT3b (40 ± 4% and 28 ± 4% at 5 and 10 years, respectively) than for pT2 and pT3a (P<.0001). The SS was also poorer in patients with pT3b tumors (91 ± 2% and 76 ± 4% at 5 and 10 years, respectively) (P<.0001). The predictors within the pT3b patient group were: PSA levels >10 ng/mL (HR: 1.9; 95% CI: 1.04-3.6; P=.04) and pathological Gleason score 8-10 (HR: 2.1; 95% CI: 1.2-3.5; P=.03). We designed a risk model that accounts for the variables involved, which entails 2 groups with different BPFS (P=.004): Group 1 (0-1 variable), with a BPFS of 46 ± 7% and 27 ± 8% at 5 and 10 years, respectively; and Group 2 (2 variables), with a BPFS of 14 ± 7% and 5 ± 5% at 5 and 10 years, respectively.

CONCLUSION

Seminal vesicle involvement severely and negatively affects the BPFS and SS. We designed a risk model with the independent influential variables in BPFS (pathological Gleason score 8-10 and PSA levels >10 ng/mL). This model confirms that pT3b tumors are a heterogeneous group, which includes an important group with better prognosis when surgical treatment is performed.

Optimizing D'Amico risk groups in radical prostatectomy through the addition of magnetic resonance imaging data

OBJECTIVES

To improve the predictive efficacy of the D'Amico risk classification system with magnetic resonance imaging (MRI) of the pelvis.

MATERIAL AND METHODS

We studied 729 patients from a series of 1310 radical prostatectomies for T1-T2 prostate cancer who underwent staging pelvic MRI. Each patient was classified with T2, T3a or T3b MRI, and N (+) patients were excluded. We identified the therapeutic factors that affected the biochemical progression-free survival (BPFS) time (prostate specific antigen [PSA] levels>0.4ng/mL) using a univariate and multivariate study with Cox models. We attempted to improve the predictive power of the D'Amico model (low risk: T1; Gleason 2-6; PSA levels<10ng/mL; intermediate risk: T2 or Gleason 7 or PSA levels 10-20ng/mL; high risk: T3 or Gleason 8-10 or PSA levels>20ng/mL).

RESULTS

In the univariate study, the clinical factors that influenced BPFS were the following: Gleason 7 (HR: 1.7); Gleason 8-10 (HR: 2.9); T2 (HR: 1.6); PSA levels 10-20 (HR: 2); PSA levels>20 (HR: 4.3); D'Amico intermediate (HR: 2.1) and high (HR: 4.8) risk; T3a MRI (HR: 2.3) and T3b MRI (HR: 4.5). In the multivariate study, the only variables that affected BPFS were the following: D'Amico intermediate risk (HR: 2; 95% CI 1.2-3.3); D'Amico high risk (HR: 4.1; 95% CI 2.4-6.8); T3a MRI (HR: 1.9; 95% CI 1.2-2.9) and T3b MRI (HR: 3.9; 95% CI 2.5-6.1). Predictive model: Using the multivariate Cox models, we assessed the weight of each variable. A value of 1 was given to D'Amico low risk and T2 MRI; a value of 2 was given to D'Amico intermediate risk and T3a MRI and a value 3 was given to D'Amico high risk and T3b MRI. Each patient had a marker that varied between 2 and 6. The best model included 3 groups, as follows: 494 (67.7%) patients in group 1, with a score of 2-3 points (HR, 1), a BPFS of 86%±2% and 79%±2% at 5 and 10 years, respectively; 179 (24.6%) patients in group 2, with a score of 4 points (HR, 3), a BPFS of 60%±4% and 54%±5% at 5 and 10 years, respectively; and 56 (7.7%) patients in group 3, with a score of 5-6 points (HR, 9.3), a BPFS of 29%±8% and 19%±7% at 5 and 10 years, respectively. The median BPFS time was 1.5 years.

CONCLUSION

MRI data significantly improves the predictive capacity of BPFS when using the D'Amico model data.