Efficacy and safety of prostate radiotherapy in de novo metastatic castration-sensitive prostate cancer (PEACE-1): a multicentre, open-label, randomised, phase 3 study with a 2 × 2 factorial design

Treatment Landscape of Prostate Cancer in the Era of PSMA Radiopharmaceutical Therapy

The treatment landscape of prostate cancer is quite complex because of the many therapeutic options available in different disease settings (hormonal treatments, chemotherapy, poly(adenosine diphosphate ribose) polymerase inhibitors, radiopharmaceutical therapy). Since in most cases we do not have comparative studies between these different agents, the best therapeutic sequence in patients with prostate cancer remains unsolved. In this review, we describe the different systemic therapeutic options available in each disease setting from localized disease to metastatic castration-resistant disease. We also indicate when to use each of these therapeutic options in the therapeutic sequence on the basis of the results of the available studies. A special focus of this review is the place of prostate-specific membrane antigen radiopharmaceutical therapy in the treatment algorithms.

Stereotactic body radiotherapy for lung oligometastatic prostate cancer: An international retrospective multicenter study

Background

Management of prostate cancer (PCa) patients with lung oligometastases remains unclear in the absence of published data.

Objective

The aim of this study was to evaluate the efficacy of Stereotactic Body Radiotherapy (SBRT) in this setting.

Design setting and participants

We conducted a multicenter retrospective study that included 35 PCa patients treated with SBRT for lung oligometastases in 7 centers across 3 countries.

Outcome measurements and statistical analysis

The efficacy was evaluated by the progression free-survival (PFS), defined as pre-SBRT PSA + 25 % or nadir PSA + 25 % and + 2 ng/mL or radiological progression if it occurred before biochemical progression. The local recurrence free-survival (LRFS), distant metastases free-survival (DMFS), Overall Survival (OS) and Androgen Deprivation Therapy free-survival were also assessed. Survival was estimated using the Kaplan Meier method.

Results

35 patients were included with lung oligometastases staged with PET-CT for 97 % and histologically biopsy confirmed for 51 %. 77 % had an oligorecurrent metastatic disease. The median pre SBRT PSA was at 1.7 ng/mL [0.8, 3.0] and the median follow-up after SBRT was 28.7 months. The median PFS was 21.6 months [95 %CI: 21.6; NA] and the median DMFS was 32.4 months [95 %CI: 22.2-NA]. No parameters were significantly associated with PFS on the univariate and multivariate models.For patients who did not start ADT before or concomitantly with SBRT (n = 18), the 1-year ADT free-survival rate was estimated at 87.2 % [71.9;100].

Conclusions

SBRT for PCa lung oligometastases offers good oncological outcomes, comparable to those reported for bone and/or lymph node metastases SBRT. Our results encourage the inclusion of patients with lung oligometastatic disease in clinical trials designed to assess the value of SBRT.

Patient summary

SBRT for prostate cancer lung oligometastases shows promising results, similar to treatments for bone or lymph node oligometastases.

Radiotherapy quality assurance for the PEACE 1 trial: An individual case review analysis

PURPOSE

Radiotherapy quality assurance (RTQA) is essential for ensuring adherence to trial protocols. This paper summarizes the individual case review (ICR) results from the PEACE-1 trial, a phase-III study investigates standard of care (androgen deprivation therapy with or without docetaxel) with or without local radiotherapy; and with or without abiraterone acetate plus prednisone in patients with metastatic hormone-sensitive prostate cancer (mHSPC).

MATERIALS AND METHODS

Participating institutions submitted radiotherapy (RT) plans for central review, assessing protocol compliance in target volume and organs at risk (OARs) delineation, as well as dose specifications. ICRs were conducted either retrospectively (r-ICRs), after starting RT, or prospectively (p-ICRs), before RT initiation. Case reviews were categorized as acceptable per protocol, acceptable variation, or unacceptable variation based on delineation and dose and plan parameters.

RESULTS

Out of 585 patients in the RT arms, 527 (90%) had r-ICRs, primarily using intensity-modulated radiotherapy (IMRT). Delineation review approved 417 (87%) r-ICRs and 44 (92%) p-ICRs. The main reasons for unacceptable delineation were erroneous clinical target volume (CTV) delineation. In dose and plan reviews, 399 (96%) r-ICRs cases and 46 (96%) p-ICRs were approved, with unacceptable cases primarily due to PTV dose distribution issues.

CONCLUSION

RTQA is crucial in prostate cancer trials, primarily for proper target volume delineation. It is recommended to omit r-ICRs due to resource demands and lack of impact on RTQA outcomes, using limited p-ICRs with early feedback for site deviations and reserving full p-ICRs for trails with new techniques or dose regimens.

CLINICALTRIALS

gov: NCT01957436.

Direct Treatment of All Visible Tumour in Synchronous Oligometastatic Prostate Cancer: Total Eradication of Tumour or the Full Monty Treatment

Recent advances in the management of synchronous oligometastatic prostate cancer (PC) highlight the potential of combining local and systemic therapies. However, there is growing interest in metastasis-directed therapy (MDT) in this setting. When all modalities are combined, this is referred as "total eradication of tumour" (TET) or "full monty treatment" (FMT). Retrospective studies have revealed promising outcomes with approaches such as cytoreductive radical prostatectomy or radiotherapy alongside MDT and combination systemic therapy. Multiple studies have demonstrated a significant proportion of cases with undetectable prostate-specific antigen and noncastrate testosterone, while one comparative trial (± MDT) revealed some evidence of an overall survival benefit. Results from the prospective trials indicate the feasibility and effectiveness of this intensive treatment strategy, with biochemical remission and disease-free states achieved in a significant proportion of cases. Overall, limitations persist, including a reliance on conventional imaging in all studies and the absence of long-term prospective data. Ongoing trials will provide definitive insights into the treatment efficacy and safety of TET/FMT. PATIENT SUMMARY: For patients with a new diagnosis of prostate cancer with only few metastases, cancer control results after treatment with local therapy, hormonal agents, and treatment targeted to all metastatic sites are promising. Further clinical trials of this approach with the inclusion of new scan techniques are eagerly awaited.

Local therapy for oligometastatic prostate cancer

Traditionally, systemic therapy based on androgen deprivation therapy (ADT) has been the primary approach for treating metastatic prostate cancer. Local therapies targeting metastatic lesions have rarely been employed for cancer control. However, the advent of next-generation imaging modalities, such as choline positron emission tomography (PET), whole-body magnetic resonance imaging, and prostate-specific membrane antigen (PSMA)-PET, has enabled the detection of oligometastases that were previously undetectable using conventional imaging techniques, such as computed tomography and bone scintigraphy. This has led to increased attention to local therapy for oligometastatic prostate cancer with cancer control. Oligometastatic prostate cancer can be classified into three categories: de novo oligometastases (oligometastases identified at initial diagnosis), oligorecurrence (oligometastases arising after radical treatment of primary tumor), and oligoprogression (activation of oligometastases following ADT failure). Evidence from randomized controlled trials (RCTs) supports the efficacy of local therapy in these contexts. The phase III STAMPEDE trial demonstrated that the addition of prostate radiotherapy to ADT improved the overall survival in patients with de novo low-volume metastatic prostate cancer. Furthermore, in the STOMP and ORIOLE trials, phase II RCTs have shown that metastasis-directed therapy significantly prolongs progression-free survival (PFS) in patients with oligorecurrent prostate cancer after radical treatment. For oligoprogressive castration-resistant prostate cancer, the phase II ARTO trial demonstrated that the addition of radiotherapy targeting oligometastases to first-line abiraterone acetate and prednisone treatments improved PFS. With the global adoption of PSMA-PET, local therapy for primary tumor and metastases in oligometastatic prostate cancer is expected to play an increasingly prominent role in the future.

Assessment of bone mineral density in men with de novo metastatic castration-sensitive prostate cancer treated with or without abiraterone acetate plus prednisone in the PEACE-1 phase 3 trial

AIM

Addition of abiraterone acetate plus prednisone (AAP) to androgen deprivation therapy (ADT) with or without docetaxel (D) improved overall survival in patients with de novo metastatic castration sensitive prostate cancer in the PEACE-1 trial. The protocol was amended during the course of the study to assess whether addition of AAP increases bone loss.

METHODS

Patients were randomized to receive either ADT + D with or without AAP. Bone mineral density (BMD) of the lumbar spine, femoral neck, and total hip were measured by dual X-ray absorptiometry at baseline, 6, 12, and 24 months (M). T-Scores and mean percent change in BMD values were assessed.

RESULTS

With 97 patients treated with AAP and 98 without, the median age was 65 years and 69 patients were ECOG 0 in each arm. Median baseline body mass index was 25.6 and 26.5 kg/m2 in patients treated with or without AAP, respectively. Ten and 30 % presented with baseline osteoporosis and osteopenia, respectively. Mean T scores and mean percent changes in BMD measured on three anatomic sites decreased during the first year of treatment in both arms, without difference between arms. At M24, a numerical two-fold increase in patients with osteoporosis was observed in the AAP arm.

CONCLUSIONS

This is the first prospective assessment of BMD in a randomized trial with an experimental treatment using AAP. Bone loss occurred rapidly in both arms, and addition of AAP did not increase bone loss significantly although a numerically higher rate of osteoporosis was observed at 2 years.

TRIAL REGISTRATION

NCT01957436.

Optimal Treatment Strategies for Hormone-sensitive Metastatic Prostate Cancer: Does Local Radiotherapy Play a Role in High-volume Disease?

Optimal treatment strategies for metastatic hormone-sensitive prostate cancer (mHSPC) are evolving with novel multimodal approaches. For well-selected patients, early local radiotherapy can play a pivotal role in high-volume mHSPC. Radiotherapy controls local disease, reduces symptoms, and may potentially delay castration resistance, warranting its consideration alongside systemic therapies in high-volume mHSPC.

Radical Prostatectomy in Multimodal Setting: Current Role of Neoadjuvant and Adjuvant Hormonal or Chemotherapy-Based Treatments

The role of neoadjuvant and adjuvant hormonal or chemotherapy-based treatments before or after radical prostatectomy in localized or locally advanced high-risk prostate cancer (PCa) is currently debatable. European guidelines recommend adjuvant androgen deprivation therapy (ADT) only in pN1 patients after extended pelvic lymph node dissection based on outdated evidence on standard hormonal agents. The introduction of new-generation androgen receptor targeting agents (ARTAs) has revolutionized the treatment of metastatic PCa and might also impact the perioperative management of patients with high-risk localized disease. In the last years, a renewed interest has also arisen in chemotherapy-based neoadjuvant or adjuvant treatments alone or in combination with ADT and/or ARTAs. In the present review, we gathered the current evidence on the oncological outcomes of neoadjuvant and adjuvant systemic treatments in surgically treated patients with localized or locally advanced PCa. Despite mild benefits in terms of pathologic responses or oncological outcomes reported in some studies investigating ADT and/or chemotherapy in this setting of patients, strong evidence to support their use in clinical practice is lacking. Promising data in favor of ARTAs have been gathered from phase II trials and prospective series, but definitive results from phase III trials are awaited to confirm these findings.

Clinical, Diagnostic and Therapeutic Framework of mHSPC and nmCRPC: A Multidisciplinary Consensus Project of the Italian Society for Uro-Oncology (SIUrO)

The recent evidences provided in metastatic hormone sensitive prostate cancer (nmHSPC) and in nonmetastatic castration resistant (nmCRPC) introduced the possibility to adopt Androgen Receptor Signaling inhibitor (ARSi) alone (both settings) or with chemotherapy (in mHSPC). In daily clinical practice there are some opening questions regarding the inclusion of next generation imaging, mainly PSMA-PET, how integrate local treatment as radiotherapy, how to select patients or drugs in a multiple-choice scenario, and how to manage patients with comorbidities and polypharmacy. These issues led the Italian Society for Uro-Oncology (SIUrO) to develop a consensus project involving all of the most important Italian scientific societies engaged in the multidisciplinary and multiprofessional management of the disease. This paper describes the items and statements approved, with the aim to support clinicians in managing metastatic hormone sensitive and nonmetastatic castration resistant prostate cancer patients.