Safety and effectiveness of neoadjuvant luteinizing hormone-releasing hormone agonist plus low-dose estramustine phosphate in high-risk prostate cancer: a prospective single-arm study

Dose compliance of estramustine phosphate in neoadjuvant chemohormonal therapy combined with degarelix acetate predicts the biochemical recurrence in patients with very high-risk prostate cancer who underwent robot-assisted radical prostatectomy

OBJECTIVES

The objective of this study is to evaluate the safety and efficacy of neoadjuvant degarelix acetate and low-dose estramustine phosphate for high-/very high-risk prostate cancer.

METHODS

Overall, 187 patients diagnosed with National Comprehensive Cancer Network high-/very high-risk cTanyN0M0 localized prostate cancer who consented to undergo robot-assisted radical prostatectomy after receiving neoadjuvant chemohormonal therapy for 6 months were prospectively enrolled between December 2017 and March 2023. Adverse events, perioperative and histopathological outcomes, and biochemical recurrence-free survival rates were examined. Survival analysis compared the estramustine phosphate completion and reduction groups.

RESULTS

Thirty-six patients discontinued neoadjuvant therapy in <5 months owing to adverse events (n = 34) or other reasons (n = 2). Eleven were excluded for being in the postoperative castration range. Of the 140 patients who underwent surgery, 124 continued with two tablets of estramustine phosphate and 16 with one tablet. Overall, 82 patients were very high-risk. Histopathological outcomes were significantly worse in the very high-risk group than those in the high-risk group. Very high-risk status and estramustine phosphate reduction were significant factors in biochemical recurrence in multivariate analysis. The biochemical recurrence-free survival rate in very high-risk patients was significantly lower in the estramustine phosphate dose reduction group than in the completion group but not significant in high-risk patients. Major adverse events were anemia (n = 174), elevated transaminase levels (n = 68), and deep vein thrombosis (n = 24). Severe adverse events included acute coronary syndrome (n = 4) and pulmonary embolism (n = 3).

CONCLUSIONS

Dose compliance with estramustine phosphate predicted biochemical recurrence in patients with very high-risk prostate cancer undergoing robot-assisted radical prostatectomy with neoadjuvant chemohormonal therapy.

Significance of pelvic lymph node dissection during radical prostatectomy in high-risk prostate cancer patients receiving neoadjuvant chemohormonal therapy

We aimed to determine the survival and staging benefit of limited pelvic lymph node dissection (PLND) during radical prostatectomy (RP) in high-risk prostate cancer (PC) patients treated with neoadjuvant chemohormonal therapy. We retrospectively analyzed 516 patients with high-risk localized PC (< cT4N0M0) who received neoadjuvant androgen-deprivation therapy plus estramustine phosphate followed by RP between January 2010 and March 2020. Since we stopped limited PLND for such patients in October 2015, we compared the surgical outcomes and biochemical recurrence-free survival (BCR-FS) between the limited-PLND group (before October 2015, n = 283) and the non-PLND group (after November 2015, n = 233). The rate of node metastases in the limited-PLND group were 0.8% (2/283). Operation time was significantly longer (176 vs. 162 min) and the rate of surgical complications were much higher (all grades; 19 vs. 6%, grade ≥ 3; 3 vs. 0%) in the limited-PLND group. The inverse probability of treatment weighting-Cox analysis revealed limited PLND had no significant impact on BCR-FS (hazard ratio, 1.44; P = 0.469). Limited PLND during RP after neoadjuvant chemohormonal therapy showed quite low rate of positive nodes, higher rate of complications, and no significant impact on BCR-FS.

A review of clinical evidence to assess differences in efficacy and safety of luteinizing hormone-releasing hormone (LHRH) agonist (goserelin) and LHRH antagonist (degarelix)

Luteinizing hormone-releasing hormone agonist (LHRH-A), goserelin, and antagonist, degarelix, are both indicated for the treatment of advanced prostate cancer (PCa); however, large comparative trials evaluating their efficacy and safety are lacking. In this review, we assessed the available evidence for both the drugs. Although degarelix achieves an early rapid decline in testosterone (T) and prostate-specific antigen (PSA) levels, median T and PSA levels, in addition to prostate volume and International Prostate Symptom Scores, become comparable with goserelin over the remaining treatment period. Degarelix causes no initial flare, therefore it is recommended in patients with spinal metastases or ureteric obstruction. Goserelin achieves lower PSA, improved time to progression, and better survival outcomes when administered adjunctively to radiotherapy compared with radiotherapy alone, with significant results even over long-term follow-up. The evidence supporting adjuvant degarelix use is limited. Goserelin has better injection site safety, single-step delivery, and an efficient administration schedule compared with degarelix, which has significantly higher injection site reactions and less efficient administration mechanism. There is conflicting evidence about the risk of cardiovascular disease (CVD), and caution is required when using LHRH-A in patients with preexisting CVD. There is considerable long-term evidence for goserelin in patients with advanced PCa, with degarelix being a more recent option. The available comparative evidence of goserelin versus degarelix has several inherent limitations related to study design, sample size, conduct, and statistical analyses, and hence warrants robust prospective trials and long-term follow-up.

Neoadjuvant hormonal therapy before radical prostatectomy in high-risk prostate cancer

Patients with high-risk prostate cancer treated with curative intent are at an increased risk of biochemical recurrence, metastatic progression and cancer-related death compared with patients treated for low-risk or intermediate-risk disease. Thus, these patients often need multimodal therapy to achieve complete disease control. Over the past two decades, multiple studies on the use of neoadjuvant treatment have been performed using conventional androgen deprivation therapy, which comprises luteinizing hormone-releasing hormone agonists or antagonists and/or first-line anti-androgens. However, despite results from these studies demonstrating a reduction in positive surgical margins and tumour volume, no benefit has been observed in hard oncological end points, such as cancer-related death. The introduction of potent androgen receptor signalling inhibitors (ARSIs), such as abiraterone, apalutamide, enzalutamide and darolutamide, has led to a renewed interest in using neoadjuvant hormonal treatment in high-risk prostate cancer. The addition of ARSIs to androgen deprivation therapy has demonstrated substantial survival benefits in the metastatic castration-resistant, non-metastatic castration-resistant and metastatic hormone-sensitive settings. Intuitively, a similar survival effect can be expected when applying ARSIs as a neoadjuvant strategy in high-risk prostate cancer. Most studies on neoadjuvant ARSIs use a pathological end point as a surrogate for long-term oncological outcome. However, no consensus yet exists regarding the ideal definition of pathological response following neoadjuvant hormonal therapy and pathologists might encounter difficulties in determining pathological response in hormonally treated prostate specimens. The neoadjuvant setting also provides opportunities to gain insight into resistance mechanisms against neoadjuvant hormonal therapy and, consequently, to guide personalized therapy.

Neoadjuvant Approaches Prior To Radical Prostatectomy

Patients with high-risk localized prostate cancer benefit from multimodality therapy of curative intent. Androgen-deprivation therapy (ADT) combined with radiation improves survival in this population. However, prior clinical trials of neoadjuvant ADT and surgery failed to consistently demonstrate a survival advantage. The development of novel, more potent hormonal agents presents an opportunity to revisit the potential for neoadjuvant therapy to improve long-term outcomes for patients with localized prostate cancer. We review recent advances in neoadjuvant approaches for prostate cancer and emerging clinical trials data supporting the use of neoadjuvant therapy prior to radical prostatectomy.

Systematic Review of Systemic Therapies and Therapeutic Combinations with Local Treatments for High-risk Localized Prostate Cancer

CONTEXT

Systemic therapies, combined with local treatment for high-risk prostate cancer, are recommended by the international guidelines for specific subgroups of patients; however, for many of the clinical scenarios, it remains a research field.

OBJECTIVE

To perform a systematic review, and describe current evidence and perspectives about the multimodal treatment of high-risk prostate cancer.

EVIDENCE ACQUISITION

We performed a systematic review of PubMED, Embase, Cochrane Library, European Society of Medical Oncology/American Society of Clinical Oncology Annual proceedings, and clinicalTrial.gov between January 2010 and February 2018 following the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement.

EVIDENCE SYNTHESIS

Seventy-seven prospective trials were identified. According to multiple randomized trials, combining androgen deprivation therapy (ADT) with external-beam radiotherapy (EBRT) outperforms EBRT alone for both relapse-free and overall survival. Neoadjuvant ADT did not show significant improvement compared with prostatectomy alone. The role of adjuvant ADT after prostatectomy in patients with high-risk disease is still debated, with lack of data from phase 3 trials in pN0 patients. Novel androgen pathway inhibitors have been tested only in early-phase trials in addition to primary treatment. GETUG 12, RTOG 0521, and nonmetastatic subgroup of the STAMPEDE trial showed improved relapse-free survival for docetaxel in patients treated with EBRT plus ADT, although mature metastasis-free survival data are still pending. Both the SPCG-12 and the VACSP#553 trial showed no improvement in relapse-free survival for adjuvant docetaxel after prostatectomy.

CONCLUSIONS

In contrast to the clearly demonstrated survival benefits of long-term adjuvant ADT when used with EBRT, its role after prostatectomy remains unclear especially in pN0 patients. Adding docetaxel to EBRT-ADT improves relapse-free survival, with immature results on overall survival. Novel androgen receptor pathway inhibitors are currently being tested in the neoadjuvant and adjuvant setting.

PATIENT SUMMARY

Treatment of high-risk prostate cancer is based on a multimodality approach that includes systemic treatments. The best treatment or therapy combination remains to be defined.

Radical Prostatectomy With and Without Neoadjuvant Chemohormonal Pretreatment for High-Risk Localized Prostate Cancer: A Comparative Propensity Score Matched Analysis

BACKGROUND

To investigate the clinical outcomes in patients with high-risk prostate cancer (PCa) treated with neoadjuvant chemohormonal therapy (NCHT) before radical prostatectomy (RP).

PATIENTS AND METHODS

Our NCHT protocol involved complete androgen blockade followed by 6 cycles of docetaxel (30 mg/m²) plus estramustine phosphate (560 mg). NCHT was provided to 60 patients with PCa before RP, and we compared the clinical and pathologic outcomes with those of 349 patients with high-risk PCa who underwent RP alone using propensity score matching. The data for those who underwent RP alone were obtained from the Michinoku Japan Urological Cancer Study Group database.

RESULTS

In the NCHT group, 10.0% experienced pathologic complete response, 3.3% had positive surgical margins, and 13.3% developed severe complications (Clavien-Dindo grade III or higher) after RP. The median follow-up duration was 42.5 months, and the 5-year biochemical recurrence (BCR)-free survival was 60.1%. In multivariate analysis, pN+ was an independent prognostic factor for BCR (hazard ratio = 5.251, 95%CI 1.300-21.201; P = .020). In propensity score matching, the BCR rate in the NCHT group was significantly lower than that in the RP alone group (P = .021). In subgroup analyses, the BCR rate in patients with a single high-risk factor was significantly lower in the NCHT group than in the RP-alone group (P = .027).

CONCLUSION

NCHT before RP can reduce the risk of BCR in patients with high-risk PCa, particularly if a single high-risk factor is present. However, the potential for perioperative complications should be considered.

Neoadjuvant chemohormonal therapy followed by robot-assisted and minimum incision endoscopic radical prostatectomy in patients with high-risk prostate cancer: comparison of perioperative and oncological outcomes at single institution

PURPOSE

Optimal management strategies for patients with high-risk prostate cancer (PCa) have not been established. This study aimed to estimate the impact of surgical procedures on perioperative and oncological outcomes in patients with high-risk PCa who received neoadjuvant chemohormonal therapy (CHT) prior to radical prostatectomy (RP).

METHODS

In this retrospective study, we focused on patients with high-risk PCa who received neoadjuvant CHT followed by RP. The enrolled patients were divided into the following two groups according to surgical procedure: the robot-assisted RP (RARP) group and minimum incision endoscopic RP (MIE-RP) group. The primary endpoint was biochemical recurrence-free survival (BRFS).

RESULTS

A total of 522 high-risk PCa patients were enrolled in this study. The median operating time was significantly shorter in the MIE-RP group than in the RARP group. The median estimated blood loss was significantly lower in the RARP group than in the MIE-RP group. The rates of positive surgical margins (PSMs) were not statistically significant in either group. During the follow-up period, biochemical recurrence (BCR) without clinical recurrence occurred in 60 (23.9%) patients in the MIE-RP group and 5 (1.8%) in the RARP group. The 5-year BRFS rate was 76.5% in the MIE-RP group and 97.6% in the RARP group (P < 0.001). On multivariate analysis, RARP, PSM, pathological T stage, and initial prostate-specific antigen were significantly associated with BCR.

CONCLUSIONS

Neoadjuvant CHT with subsequent RARP may decrease the risk of BCR when compared to MIE-RP.

Cost-effectiveness comparison between neoadjuvant chemohormonal therapy and extended pelvic lymph node dissection in high-risk prostate cancer patients treated with radical prostatectomy: a multi-institutional analysis

The aim of the present study was to assess the cost-effectiveness of extended pelvic lymph node dissection (ePLND) compared to neoadjuvant chemohormonal therapy using gonadotropin-releasing hormone agonist/antagonist and estramustine. We retrospectively analyzed data within Michinoku Urological Cancer Study Group database containing 2971 PC patients treated with radical prostatectomy (RP) at four institutes between July 1996 and July 2017. We identified 237 and 403 high-risk patients who underwent RP and ePLND (ePLND group), and neoadjuvant chemohormonal therapy followed by RP and limited PLND (neoadjuvant group), respectively. The oncological outcomes and cost-effectiveness were compared between groups. Medical cost calculation focused on PC-related medication and adjuvant radiotherapy. Biochemical recurrence-free and overall survival rates in the neoadjuvant group were significantly higher than those in the ePLND group. Significantly higher number of patients progressed to castration-resistant PC in the ePLND group than in the neoadjuvant group. Background-adjusted multivariate Cox regression analysis using inverse probability of treatment weighting (IPTW) revealed that neoadjuvant chemohormonal therapy independently reduced the risk of biochemical recurrence after RP. The 5-year cost per person was significantly higher in the ePLND group than in the neoadjuvant group. Although the present study was retrospective, neoadjuvant chemohormonal therapy followed by RP as a concurrent strategy has potential to improve oncological outcome and cost-effectiveness.

Overall survival of high-risk prostate cancer patients who received neoadjuvant chemohormonal therapy followed by radical prostatectomy at a single institution

BACKGROUND

The optimal treatment for high-risk prostate cancer (PCa) remains to be established. We previously reported favorable, biochemical recurrence-free survival in high-risk PCa patients treated with a neoadjuvant gonadotropin-releasing hormone agonist or antagonist and estramustine phosphate (EMP) (chemohormonal therapy; CHT) followed by radical prostatectomy (RP). We conducted a retrospective study to elucidate the clinical benefit of neoadjuvant CHT for high-risk PCa patients.

METHODS

We reviewed the clinical and pathological records of 1254 PCa patients who underwent RP and bilateral pelvic lymphadenectomy between July 1996 and April 2016 at Hirosaki University. According to the D'Amico risk classification, we focused on 613 patients in the high-risk group. The high-risk PCa patients were further divided into two groups based on whether the patients received neoadjuvant CHT before RP (EMP group) or not (non-EMP group). The endpoint was overall survival (OS) after surgery.

RESULTS

The 5- and 10-year OS rates were 98.5 and 92.6%, respectively. The 10-year OS rate in the EMP group was significantly higher compared to the non-EMP group (P = 0.021). In multivariate analysis, administration of neoadjuvant CHT, lymph node involvement, and castration-resistant PCa status were significantly associated with OS.

CONCLUSIONS

RP with neoadjuvant CHT using EMP for high-risk PCa patients provided excellent long-term OS.

The impact of extended lymph node dissection versus neoadjuvant therapy with limited lymph node dissection on biochemical recurrence in high-risk prostate cancer patients treated with radical prostatectomy: a multi-institutional analysis

The optimal treatment for high-risk prostate cancer (Pca) remains to be established. The current guidelines recommend extended pelvic lymph node dissection (e-PLND) for selected intermediate- and high-risk patients treated with RP. However, the indications, optimal extent, and therapeutic benefits of e-PLND remain unclear. The aim of this study was to assess whether e-PLND confers an oncological benefit for high-risk Pca compared to neoadjuvant luteinizing hormone-releasing hormone and estramustine (LHRH + EMP). The Michinoku Urological Cancer Study Group database contained the data of 2403 consecutive Pca patients treated with RP at four institutes between March 2000 and December 2014. In the e-PLND group, we identified 238 high-risk Pca patients who underwent RP and e-PLND, with lymphatic tissue removal around the obturator and the external iliac regions, and hypogastric lymph node dissection. The neoadjuvant therapy with limited PLND (l-PLND) group included 280 high-risk Pca patients who underwent RP and removal of the obturator node chain between September 2005 and June 2014 at Hirosaki University. The outcome measure was BRFS. The 5-year biochemical recurrence-free survival rates for the neoadjuvant therapy with l-PLND group and e-PLND group were 84.9 and 54.7%, respectively (P < 0.0001). The operative time was significantly longer in the e-PLND group compared to that of the neoadjuvant therapy with l-PLND group. Grade 3/4 surgery-related complications were not identified in both groups. Although the present study was not randomized, neoadjuvant LHRH + EMP therapy followed by RP might reduce the risk of biochemical recurrence.

Neoadjuvant luteinizing-hormone-releasing hormone agonist plus low-dose estramustine phosphate improves prostate-specific antigen-free survival in high-risk prostate cancer patients: a propensity score-matched analysis

BACKGROUND

The optimal treatment for high-risk prostate cancer (Pca) remains to be established. We previously reported favorable biochemical recurrence-free survival (BRFS) in high-risk Pca patients treated with a neoadjuvant therapy comprising a luteinizing-hormone-releasing hormone (LHRH) agonist plus low dose estramustine phosphate (EMP) (LHRH+EMP) followed by radical prostatectomy (RP). In the present study, we used a retrospective design via propensity score matching to elucidate the clinical benefit of neoadjuvant LHRH+EMP for high-risk Pca.

METHODS

The Michinoku Urological Cancer Study Group database contained data for 1,268 consecutive Pca patients treated with RP alone at 4 institutions between April 2000 and March 2011 (RP alone group). In the RP alone group, we identified 386 high-risk Pca patients. The neoadjuvant LHRH+EMP group included 274 patients with high-risk Pca treated between September 2005 and November 2013 at Hirosaki University. Neoadjuvant LHRH+EMP therapy included LHRH and EMP administration at a dose of 280 mg/day for 6 months before RP. The outcome measures were overall survival (OS) and BRFS.

RESULTS

The propensity score-matched analysis indicated 210 matched pairs from both groups. The 5-year BRFS rates were 90.4 and 65.8 % for the neoadjuvant LHRH+EMP and RP alone groups, respectively (P < 0.0001). The 5-year OS rates were 100 and 96.1 % for the neoadjuvant LHRH+EMP and RP alone groups, respectively (P = 0.110).

CONCLUSIONS

Although the present study was not randomized, neoadjuvant LHRH+EMP therapy followed by RP appeared to reduce the risk of biochemical recurrence. A prospective randomized study is warranted to determine the clinical implications of the neoadjuvant therapy described here.

Both radical prostatectomy following treatment with neoadjuvant LHRH agonist and estramustine and radiotherapy following treatment with neoadjuvant hormonal therapy achieved favorable oncological outcome in high-risk prostate cancer: a propensity-score matching analysis

Background

To date, the different treatment modalities for high-risk prostate cancer (Pca) have not been compared in any sufficiently large-scale, prospective, randomized clinical trial. We used propensity-score matching analysis to compare the oncological outcomes of high-risk prostate cancer between patients treated with radical prostatectomy (RP) and those treated with radiation therapy (RT).

Methods

We studied 216 patients who received neoadjuvant therapy followed by RP (RP cohort) and 81 patients who received neoadjuvant androgen-deprivation therapy (ADT) followed by RT (RT cohort). The RP cohort received a luteinizing hormone-releasing hormone agonist and estramustine phosphate (280 mg/day) for 6 months prior to RP. The RT cohort received ADT for at least 6 months prior to RT using a 3-dimensional conformal radiotherapy technique. The total radiation dose was 70 to 76 Gy administered at 2 Gy/fraction.

Results

Propensity-score matching identified 78 matched pairs of patients. The 3-year overall survival rates were 98.3% and 92.1% in the RP and RT groups, respectively (P = 0.156). The 3-year biochemical recurrence-free survival rates were 86.4% and 89.4% in the RP and RT groups, respectively (P = 0.878).

Conclusions

Our study findings may suggest almost identical cancer control of RP and RT with appropriate neoadjuvant therapy in high-risk Pca. Therefore, issues of health-related quality of life may have an important impact on decision making in treatment of high-risk Pca.