Oncological Outcomes of Metastasis-Directed Therapy in Oligorecurrent Prostate Cancer Patients Following Radical Prostatectomy

Salvage vesiculectomy for local prostate cancer recurrence: surgical technique and early post-operative outcomes

PURPOSE

Isolated recurrence in remnants of the seminal vesicles (SV) after treatment of primary prostate cancer (PCa) has become a more frequent entity with the widespread use of more sensitive next-generation imaging modalities. Salvage vesiculectomy is hypothesized to be a worthwhile management option in these patients. The primary goal of this study is to describe the surgical technique of this new treatment option. Secondary outcomes are peri- and post-operative complications and early oncological outcomes.

METHODS

Retrospective multicenter study, including 108 patients with solitary recurrence in the SV treated between January 2009 and June 2022, was performed. Patients with local recurrences outside the SVs or with metastatic disease were excluded. Both SVs were resected using a robot-assisted or an open approach. In selected cases, a concomitant lymphadenectomy was performed.

RESULTS

Overall, 31 patients (29%) reported complications, all but one grade 1 to 3 on the Clavien-Dindo Scale. A median PSA decrease of 2.07 ng/ml (IQR: 0.80-4.33, p < 0.001), translating into a median PSA reduction of 92% (IQR: 59-98%) was observed. At a median follow-up of 14 months, freedom from secondary treatment was 54%. Lymphadenectomy had a significant influence on PSA reduction (p = 0.018).

CONCLUSION

Salvage vesiculectomy for PCa recurrence limited to the SV is a safe procedure with excellent PSA response and is a potential curative treatment in a subset of patients. A concomitant lymphadenectomy can best be performed in all patients that did not underwent one at primary treatment.

Predictors of Recurrence After Metastasis-directed Therapy in Oligorecurrent Prostate Cancer Following Radical Prostatectomy

BACKGROUND

Metastasis-directed therapy (MDT) is performed to delay systemic treatments for oligorecurrent disease after primary prostate cancer (PCa) treatment.

OBJECTIVE

The aim of this study was to identify the predictors of therapeutic response of MDT for oligorecurrent PCa.

DESIGN, SETTING, AND PARTICIPANTS

bicentric, retrospective study, including consecutive patients who underwent MDT for oligorecurrent PCa after radical prostatectomy (RP; 2006-2020) was conducted. MDT encompassed stereotactic body radiation therapy (SBRT), salvage lymph node dissection (sLND), whole-pelvis/retroperitoneal radiation therapy (WP[R]RT), or metastasectomy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

ndpoints were 5-yr radiographic progression-free survival (rPFS), metastasis-free survival (MFS), palliative androgen deprivation treatment (pADT)-free survival, and overall survival (OS) together with prognostic factors for MFS following primary MDT. Survival outcomes were studied by Kaplan-Meier survival and univariable Cox regression (UVA).

RESULTS AND LIMITATIONS

A total of 211 MDT patients were included; 122 (58%) developed a secondary recurrence. Salvage lymph node dissection was performed in 119 (56%), SBRT in 48 (23%), and WP(R)RT in 31 (15%) of the cases. Two patients received sLND + SBRT and one received sLND + WPRT. Eleven (5%) patients received metastasectomies. The median follow-up since RP was 100 mo, while follow-up after MDT was 42 mo. The 5-yr rPFS, MFS, androgen deprivation treatment(-free survival, castration-resistant prostate cancer-free survival, CSS, and OS after MDT were 23%, 68%, 58%, 82%, 93%, and 87% respectively. There was a statistically significant difference between cN1 (n = 114) and cM+ (n = 97) for 5-yr MFS (83% vs 51%, p < 0.001), pADT-free survival (70% vs 49%, p = 0.014), and CSS (100% vs 86%, p = 0.019). UVA was performed to assess the risk factors (RFs) for MFS in cN1 and cM+. Alpha was set at 10%. RFs for MFS in cN1 were lower initial prostate-specific antigen (PSA) at the time of RP (hazard ratio [95% confidence interval] 0.15 [0.02-1.02], p = 0.053], pN stage at RP (2.91 [0.83-10.24], p = 0.096), nonpersisting PSA after RP (0.47 [0.19-1.12], p = 0.089), higher PSA at primary MDT (2.38 [1.07-5.24], p = 0.032), and number of positive nodes on imaging (1.65 [1.14-2.40], p < 0.01). RFs for MFS in cM+ were higher pathological Gleason score (1.86 [0.93-3.73], p = 0.078), number of lesions on imaging (0.77 [0.57-1.04], p = 0.083), and cM1b/cM1c (non-nodal metastatic recurrence; 2.62 [1.58-4.34], p < 0.001).

CONCLUSIONS

Following MDT, 23% of patients were free of a second recurrence at 5-yr follow-up. Moreover, cM+ patients had significantly worse outcomes in terms of MFS, pADT-free survival, and CSS. The RFs for a metastatic recurrence can be used for counseling patients, to inform prognosis, and potentially select candidates for MDT.

PATIENT SUMMARY

In this paper, we looked at the outcomes of using localized, patient-tailored treatment for imaging-detected recurrent prostate cancer in lymph nodes, bone, or viscera (maximum five recurrences on imaging). Our results showed that targeted treatment of the metastatic lesions could delay the premature use of hormone therapy.

Computed Tomography-Based Radiomics for Long-Term Prognostication of High-Risk Localized Prostate Cancer Patients Received Whole Pelvic Radiotherapy

Given the high death rate caused by high-risk prostate cancer (PCa) (>40%) and the reliability issues associated with traditional prognostic markers, the purpose of this study is to investigate planning computed tomography (pCT)-based radiomics for the long-term prognostication of high-risk localized PCa patients who received whole pelvic radiotherapy (WPRT). This is a retrospective study with methods based on best practice procedures for radiomics research. Sixty-four patients were selected and randomly assigned to training (n = 45) and testing (n = 19) cohorts for radiomics model development with five major steps: pCT image acquisition using a Philips Big Bore CT simulator; multiple manual segmentations of clinical target volume for the prostate (CTVprostate) on the pCT images; feature extraction from the CTVprostate using PyRadiomics; feature selection for overfitting avoidance; and model development with three-fold cross-validation. The radiomics model and signature performances were evaluated based on the area under the receiver operating characteristic curve (AUC) as well as accuracy, sensitivity and specificity. This study's results show that our pCT-based radiomics model was able to predict the six-year progression-free survival of the high-risk localized PCa patients who received the WPRT with highly consistent performances (mean AUC: 0.76 (training) and 0.71 (testing)). These are comparable to findings of other similar studies including those using magnetic resonance imaging (MRI)-based radiomics. The accuracy, sensitivity and specificity of our radiomics signature that consisted of two texture features were 0.778, 0.833 and 0.556 (training) and 0.842, 0.867 and 0.750 (testing), respectively. Since CT is more readily available than MRI and is the standard-of-care modality for PCa WPRT planning, pCT-based radiomics could be used as a routine non-invasive approach to the prognostic prediction of WPRT treatment outcomes in high-risk localized PCa.

Multi-institutional Development and Validation of Contouring Guidelines for Para-aortic Elective Nodal Irradiation in Prostate Cancer Based on Patterns of Involvement on Targeted Molecular Imaging Positron Emission Tomography/Computed Tomography

PURPOSE

Molecular imaging better identifies anatomic regions of metastatic spread of prostate cancer compared with conventional imaging, resulting in para-aortic (PA) nodal metastases being increasingly identified. Consequently, some radiation oncologists electively treat the PA lymph node region in patients with gross or high risk of PA nodal involvement. The anatomic locations of at-risk PA lymph nodes for prostate cancer are unknown. Our objective was to use molecular imaging to develop guidelines for the optimal delineation of the PA clinical target volume (CTV) in patients with prostate cancer.

METHODS AND MATERIALS

We conducted a multi-institutional retrospective cohort study of patients with prostate cancer undergoing 18F-fluciclovine or 18F-DCFPyL prostate-specific membrane antigen positron emission tomography (PET)/computed tomography (CT). Images of patients with PET-positive PA nodes were imported into the treatment planning system, avid nodes were contoured, and measurements were taken in relation to anatomic landmarks. A contouring guideline that encompassed the location of ≥95% of PET-positive PA nodes was created using descriptive statistics and then validated in an independent data set.

RESULTS

Five hundred fifty-nine patients had molecular PET/CT imaging in the development data set (78% 18F-fluciclovine, 22% prostate-specific membrane antigen). Seventy-six patients (14%) had evidence of PA nodal metastasis. We determined that expanding the CTV to 1.8 cm left of the aorta, 1.4 cm right of the inferior vena cava (IVC), 7 mm posterior to the aorta/IVC or to the vertebral body, and superiorly to the T11/T12 vertebral interface, with the anterior border 4 mm anterior to the aorta/IVC and inferior border at the bifurcation of the aorta/IVC, resulted in coverage of ≥95% of PET-positive PA nodes. When the guideline was used in the independent validation data set (246 patients with molecular PET/CT imaging, of whom 31 had PA nodal metastasis), 97% of nodes were encompassed, thereby validating our guideline.

CONCLUSIONS

We used molecular PET/CT imaging to determine the anatomic locations of PA metastases to develop contouring guidelines for creating a prostate cancer PA CTV. Although the optimal patient selection and clinical benefits of PA radiation therapy remain uncertain, our results will aid in delineating the optimal target when PA radiation therapy is pursued.

Penile metastasis in prostate cancer patients: Two case reports, surgical excision technique, and literature review

Two cases of penile metastasis from primary prostate cancer in a single center are presented, along with a literature review and description of the excision technique. Despite its rich vascularization, penile metastasis is rare, with 72 new cases from September 2006 to March 2021. There is a wide variety of diagnoses, treatments, and prognoses for penile metastatic lesions. Ga-68 prostatespecific membrane antigen positron emission tomography/computed tomography is the most sensitive imaging tool for detecting metastasis from primary prostate cancer. Magnetic resonance imaging of the penis is the most reliable technique for differentiating penile lesions. Histological diagnosis is mostly performed using fine-needle biopsy aspiration. Metastasis-directed treatment is not considered to contribute to prolonged survival. Local treatment is feasible and can be offered to symptomatic patients. Owing to a heterogeneous group, defining overall survival is difficult. Survival until 46months after detecting penile metastases is described.

Node Oligorecurrence in Prostate Cancer: A Challenge

Within the oligometastatic state, oligorecurrent lymph node disease in prostate cancer represents an interesting clinical entity characterized by a relatively indolent biology that makes it unique: it can be treated radically, and its treatment is usually associated with a long period of control and excellent survival. Additionally, it is an emergent situation that we are facing more frequently mainly due to (a) the incorporation into clinical practice of the PSMA-PET that provides strikingly increased superior images in comparison to conventional imaging, with higher sensitivity and specificity; (b) the higher detection rates of bone and node disease with extremely low levels of PSA; and (c) the availability of high-precision technology in radiotherapy treatments with the incorporation of stereotaxic body radiotherapy (SBRT) or stereotaxic ablative radiotherapy (SABR) technology that allows the safe administration of high doses of radiation in a very limited number of fractions with low toxicity and excellent tolerance. This approach of new image-guided patient management is compelling for doctors and patients since it can potentially contribute to improving the clinical outcome. In this work, we discuss the available evidence, areas of debate, and potential future directions concerning the utilization of new imaging-guided SBRT for the treatment of nodal recurrence in prostate cancer.

Prostate and metastasis-directed focal therapy in prostate cancer: hype or hope?

INTRODUCTION

The paradigm of focal therapy's role in metastatic patients is being challenged by evolving attitudes and emerging data. At the current time, specifically regarding prostate cancer, does the evidence indicate this is more hype or hope?

AREAS COVERED

We searched the literature via PubMed, MEDLINE, and Embase for studies from 2014 to the present addressing focal therapy with non-palliative intent in metastatic prostate cancer patients, emphasizing prospective trials when available. We sought to address all common clinical scenarios: de novo synchronous diagnosis, oligorecurrence, oligoprogression, and mCRPC disease.

EXPERT OPINION

Current evidence is strongest, and in our opinion practice-changing, for prostate-directed RT in de novo metastatic patients with low metastatic burden. Metastasis-directed therapy with SBRT is consistently shown to have low rates of toxicity, and promising rates of ADT-free survival and progression-free survival. These can be utilized on a patient-by-patient basis with these endpoints in mind, but do not yet show sufficient benefit to be standard of care. This is a rich area of ongoing research, and many trials should publish in the coming years to shed light on many unanswered questions, including the role of cytoreductive prostatectomy, systemic therapy combined with MDT, and the integration of modern PET imaging.

Defining the optimal template of salvage lymph node dissection for unilateral pelvic nodal recurrence of prostate cancer following radical prostatectomy

OBJECTIVES

Several retrospective studies have shown that salvage bilateral pelvic lymph node dissection (sLND) is a valid treatment option in the setting of oligorecurrent nodal prostate cancer following radical prostatectomy. Little is known about the optimal template of such sLND in patients with strictly unilateral pelvic recurrence on PET-CT imaging. In this study, we investigated whether a unilateral pelvic sLND could be sufficient in such a setting.

METHODS

We retrospectively collected data of patients treated with sLND between 2010 and 2019 at the University Hospitals, Leuven. Patients were included if they developed recurrence following radical prostatectomy, characterized by ≤3 unilateral pelvic lymph node metastases on Choline or PSMA PET-CT and received a super-extended bilateral pelvic sLND as first metastasis-directed therapy. As a primary endpoint, we investigated in how many cases a unilateral sLND would have been sufficient.

RESULTS

In total, 44 patients with strictly unilateral pelvic recurrence were treated with super-extended bilateral pelvic sLND. In 5 out of 44 (11%) patients, histological examination showed presence of prostate cancer in the contralateral hemi-pelvis. In the group with a single positive node on imaging prior to sLND, only 1 out of 27 (3%) patients had contralateral disease at final pathology. No one (0%) in this group subsequently developed recurrence in the contralateral hemi-pelvis following sLND.

CONCLUSIONS

In conclusion, this study suggests that unilateral pelvic sLND could be sufficient in patients with a single unilateral pelvic lymph node recurrence on PET/CT imaging.

Choline PET/CT in recurrent prostate cancer

Purpose

Biochemical recurrence (BR) occurs in up to 40% of patients with prostate cancer (PCa) treated with primary radical prostatectomy (RP). Choline PET/CT may show, in a single-step examination, the site of tumor recurrence earlier than traditional imaging methods, particularly at low prostate-specific antigen (PSA) levels, thus influencing subsequent treatment.

Methods/patients

Patients with recurrent and non-metastatic prostate cancer (nmPCa), who were assessed with choline PET/CT, were included in the analysis. Based on imaging results, the following therapeutic strategies were chosen: radiotherapy to the prostatic bed, androgen deprivation therapy (ADT), and chemotherapy or stereotactic body radiotherapy (SBRT) to either the pelvic lymph nodes or distant metastases. We assessed the impact of age, PSA levels, Gleason score (GS), and adjuvant therapy on oncological outcomes.

Results

Data from 410 consecutive nmPCa patients with BR who underwent RP as primary treatment were analyzed. One hundred seventy-six (42.9%) patients had a negative choline PET/CT, and 234 (57.1%) patients resulted positive. In the multivariate analysis, only chemotherapy and PSA at recurrence were significant independent prognostic factors on overall survival (OS). In the PET-positive subgroup, the number of relapses, PSA post-prostatectomy, and chemotherapy impacted on OS. PSA (post-surgery and at recurrence) affected progression-free survival (PFS) in the univariate analysis. In the multivariate analysis, GS, the number of relapse sites, and PSA (post-surgery and at recurrence) were significant prognostic factors for disease-free survival (DFS).

Conclusion

Choline PET/CT provides better accuracy than conventional imaging for the assessment of nmPCa with BR after prostatectomy, thereby enabling salvage strategies and improving quality of life.

SPARKLE: a new spark in treating oligorecurrent prostate cancer: adding systemic treatment to stereotactic body radiotherapy or metastasectomy: key to long-lasting event-free survival?

BACKGROUND

Metastasis-directed therapy (MDT) significantly delays the initiation of palliative androgen deprivation therapy (pADT) in patients with oligorecurrent prostate cancer (PCa) with a positive impact on patient's quality of life. However, it remains unclear whether the addition of ADT improves polymetastatic free survival (PMFS) and metastatic castration refractory PCa-free survival (mCRPC-FS) and how long concomitant hormone therapy should be given. A significant overall survival (OS) benefit was shown when an androgen receptor targeted agent (ARTA) was added to pADT in patients with metastatic hormone sensitive PCa (HSPC). However, whether the addition of and ARTA to MDT in the treatment of oligorecurrent PCa results in better PMFS and mCRPC-FS has not been proven yet.

METHODS & DESIGN

Patients diagnosed with oligorecurrent HSPC (defined as a maximum of 5 extracranial metastases on PSMA PET-CT) will be randomized in a 1:1:1 allocation ratio between arm A: MDT alone, arm B: MDT with 1 month ADT, or arm C: MDT with 6 months ADT together with ARTA (enzalutamide 4 × 40 mg daily) for 6 months. Patients will be stratified by PSA doubling time (≤ 3 vs. > 3 months), number of metastases (1 vs. > 1) and initial localization of metastases (M1a vs. M1b and/or M1c). The primary endpoint is PMFS, and the secondary endpoints include mCRPC-FS, biochemical relapse-free survival (bRFS), clinical progression free survival (cPFS), cancer specific survival (CSS), overall survival (OS), quality of life (QOL) and toxicity.

DISCUSSION

This is the first prospective multicentre randomized phase III trial that investigates whether the addition of short-term ADT during 1 month or short-term ADT during 6 months together with an ARTA to MDT significantly prolongs PMFS and/or mCRPC-FS.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05352178, registered April 28, 2022.

The current role of precision surgery in oligometastatic prostate cancer

Oligometastatic prostate cancer (omPCa) is a novel intermediate disease state characterized by a limited volume of metastatic cells and specific locations. Accurate staging is paramount to unmask oligometastatic disease, as provided by prostate-specific membrane antigen-positron emission tomography. Driven by the results of prospective trials employing conventional and/or modern staging modalities, the treatment landscape of omPCa has rapidly evolved over the last years. Several treatment-related questions comprising the concept of precision strikes are under development. For example, beyond systemic therapy, cohort studies have found that cytoreductive radical prostatectomy (CRP) can confer a survival benefit in select patients with omPCa. More importantly, CRP has been consistently shown to improve long-term local symptoms when the tumor progresses across disease states due to resistance to systemic therapies. Metastasis-directed treatments have also emerged as a promising treatment option due to the visibility of oligometastatic disease and new technologies as well as treatment strategies to target the novel PCa colonies. Whether metastases are present at primary cancer diagnosis or detected upon biochemical recurrence after treatment with curative intent, targeted yet decisive elimination of disseminated tumor cell hotspots is thought to improve survival outcomes. One such strategy is salvage lymph node dissection in oligorecurrent PCa which can alter the natural history of progressive PCa. In this review, we will highlight how refinements in modern staging modalities change the classification and treatment of (oligo-)metastatic PCa. Further, we will also discuss the current role and future directions of precision surgery in omPCa.

Long-term cancer survivors treated with multiple courses of repeat radiation therapy

Introduction and background

Through recent advances in cancer care, the number of long-term survivors has continuously increased. As a result, repetitive use of local radiotherapy for curative or palliative indications might have increased as well. This analysis aims to describe patterns of care and outcome of patients treated with multiple courses of repeat radiotherapy.

Materials and methods

All patients treated with radiotherapy between 2011 and 2019 at our department of Radiation Oncology were included into this analysis. A course of radiotherapy was defined as all treatment sessions to one anatomical site under one medical indication. Demographics, cancer and treatment characteristics and overall survival of patients having undergone multiple radiotherapy courses (minimum n = 5) were evaluated.

Results

The proportion of cancer patients treated with a minimum five courses of radiotherapy increased continuously from 0.9% in 2011 to 6.5% in 2019. In the 112 patients treated with a minimum of five radiotherapy courses, the primary tumor was lung in 41.9% (n = 47), malignant melanoma in 8.9% (n = 10) and breast in 8.0% (n = 9) of cases. A median interval of 3 years (maximum 8 years) elapsed between the first and the last radiotherapy course. The maximum number of courses in a single patient were n = 10. Treatment intent was curative or palliative in 46.4% and 53.6% for the first radiotherapy, respectively. The proportion of curative intent decreased to 11.6% at the 5th, and the last radiotherapy course was following a palliative intent in all patients. Five-year overall survival measured from the 1st radiotherapy course was 32.7%. Median overall survival was 3.3, 2.4, 1.3, and 0.6 years when measured from the 1st, the 1st palliative, the 5th and last course of radiotherapy, respectively.

Discussion and conclusion

A continuously increasing number of patients is treated with multiple courses of radiotherapy throughout their long-term cancer survivorship.

Local Therapies in Oligometastatic and Oligoprogressive Prostate Cancer

Oligometastatic disease was originally defined by Hellman and Weichselbaum as an intermediate-state existing between locally confined and widely disseminated malignancy, whose natural history could be positively impacted with systemic and importantly local therapies such as radiation. Currently oligometastatic prostate cancer (OPCa) is defined clinically by lesion enumeration and several subgroups exist: de novo (synchronous) oligometastatic disease present at initial diagnosis, oligorecurrent (metachronous) disease arising after definitive therapy to the prostate, and oligoprogressive disease where isolated lesions progress in a background of otherwise stable disease. In this review we highlight current knowledge and the potential future of local therapies, such as radiation to the primary prostate and metastasis-directed therapy (MDT), in the disease management of OPCa for all 3 subgroups. In addition, we examine more recent studies classifying the patterns of failure and natural history of OPCa following treatment with local therapies. Finally, while current clinical definitions of OPCa dominate, we introduce studies attempting to elucidate a more biological definition of OPCa to allow for improved selection of patients to treat with local therapies and to better inform precision combination approaches with systemic therapy.

Actuarial Analysis of Survival among Breast Cancer Patients in Lithuania

Breast cancer is the most common cause of mortality due to cancer for women both in Lithuania and worldwide. Chances of survival after diagnosis differ significantly depending on the stage of disease at the time of diagnosis. Extended term periods are required to estimate survival of, e.g., 15–20 years. Moreover, since mortality of the average population changes with time, estimates of survival of cancer patients derived after a long period of observation can become outdated and can be no longer used to estimate survival of patients who were diagnosed later. Therefore, it can be useful to construct analytic functions that describe survival probabilities. Shorter periods of observation can be enough for such construction. We used the data collected by the Lithuanian Cancer Registry for our analysis. We estimated the chances of survival for up to 5 years after patients were diagnosed with breast cancer in Lithuania. Then we found analytic survival functions which best fit the observed data. At the end of this paper, we provided some examples for applications and directions for further research. We used mainly the Kaplan–Meier method for our study.

Radiotherapy of oligometastatic prostate cancer: a systematic review

BACKGROUND

Due to improved imaging sensitivity, the term "oligometastatic" prostate cancer disease is diagnosed more often, leading to an increasing interest in metastasis-directed therapy (MDT). There are two types of radiation based MDT applied when treating oligometastatic disease: (1) stereotactic body radiation therapy (SBRT) generally used for bone metastases; or (2) SBRT for isolated nodal oligometastases combined with prophylactic elective nodal radiotherapy. This review aims to summarize current evidence data, which may shed light on the optimal management of this heterogeneous group of patients.

METHODS

A systematic review of the Medline database through PubMed was performed according to PRISMA guidelines. All relevant studies published up to November 2020 were identified and screened. Fifty-six titles were included. Besides outcome parameters, different prognostic and predictive factors were assessed, including site of metastases, time between primary treatment and MDT, use of systemic therapies, hormone sensitivity, as well as pattern of recurrence.

FINDINGS

Evidence consists largely of retrospective case series and no consistent precise definition of oligometastasis exists, however, most investigators seem to acknowledge the need to distinguish between patients presenting with what is frequently called "synchronous" versus "metachronous" oligometastatic disease. Available data on radiotherapy as MDT demonstrate high local control rates and a small but relevant proportion of patients without progressive disease after 2 years. This holds true for both hormone sensitive and castration resistant prostate cancer diseases. The use of 68Ga-PSMA PET/CT for staging increased dramatically. Radiation doses and field sizes varied considerably among the studies. The search for relevant prognostic and predictive factors is ongoing.

CONCLUSIONS

To our best knowledge this review on oligometastatic prostate cancer included the largest number of original articles. It demonstrates the therapeutic potential and challenges of MDT for oligometastatic prostate cancer. Prospective studies are under way and will provide further high-level evidence.

Oligorecurrent prostate cancer treated with metastases-directed therapy or standard of care: a single-center experience

BACKGROUND

The optimal treatment for oligorecurrent prostate cancer (PCa) is a matter of debate. We aimed to assess oncologic outcomes of patients treated with metastasis-directed therapy (MDT) vs. androgen deprivation therapy (ADT) for oligorecurrent PCa.

METHODS

We analyzed data from patients with oligorecurrent PCa treated with ADT (n = 121), salvage lymph node dissection (sLND) (n = 191) or external beam RT (EBRT) (n = 178). Radiological recurrence (RAR) was defined as a positive positron emission tomography imaging after MDT or ADT. Second-line systemic therapies (SST) were defined as any systemic therapy administered for progression. Oncologic outcomes were evaluated separately for patients with node-only or bone metastases. Kaplan-Meier method was used to assess time to RAR, SST, and cancer-specific mortality (CSM). Predictors of RAR, SST, and castration-resistant PCa (CRPCa) were assessed with Cox regression analyses.

RESULTS

Overall, 74 (22.6%), 63 (19.2%), and 191 (58.2%) patients were treated with ADT, EBRT, and sLND for lymph node-only recurrence. Both sLND (HR 0.56, 95% CI 0.33-0.94) and EBRT (HR 0.46, 95% CI 0.25-0.85) were associated with better RAR than ADT. Similarly, sLND (HR 0.25, 95% CI 0.13-0.50) and EBRT (HR 0.41, 95% CI 0.19-0.87) were associated with longer SST, as compared with ADT. Similar results were found for CRPCa status. Oncologic outcomes were similar between sLND and EBRT. MDT was not associated with survival benefit in patients with bone metastases as compared with ADT.

CONCLUSIONS

sLND and EBRT were associated with better RAR, SST, and CRPCa-free survival as compared with ADT in patients with oligometastatic PCa nodal recurrence. No difference in survival outcomes was observed between sLND and EBRT. MDT was not associated with survival benefit in patients with bone metastases, as compared with ADT.