Identification of Site-specific Recurrence Following Primary Radiation Therapy for Prostate Cancer Using C-11 Choline Positron Emission Tomography/Computed Tomography: A Nomogram for Predicting Extrapelvic Disease

Application of Advanced Imaging to Prostate Cancer Diagnosis and Management: A Narrative Review of Current Practice and Unanswered Questions

Major advances in prostate cancer diagnosis, staging, and management have occurred over the past decade, largely due to our improved understanding of the technical aspects and clinical applications of advanced imaging, specifically magnetic resonance imaging (MRI) and prostate-cancer-specific positron emission tomography (PET). Herein, we review the established utility of these important and exciting technologies, as well as areas of controversy and uncertainty that remain important areas for future study. There is strong evidence supporting the utility of MRI in guiding initial biopsy and assessing local disease. There is debate, however, regarding how to best use the imaging modality in risk stratification, treatment planning, and assessment of biochemical failure. Prostate-cancer-specific PET is a relatively new technology that provides great value to the evaluation of newly diagnosed, treated, and recurrent prostate cancer. However, its ideal use in treatment decision making, staging, recurrence detection, and surveillance necessitates further research. Continued study of both imaging modalities will allow for an improved understanding of their best utilization in improving cancer care.

Stereotactic Body Radiation Therapy Salvage for Lymph Node Recurrent Prostate Cancer in the Era of PSMA PET Imaging

PURPOSE OF REVIEW

Our understanding of patterns of prostate cancer recurrence after primary treatment of localized disease has significantly evolved since the development of positron emission tomography (PET) agents targeting prostate cancer. Previously, most biochemical recurrences were not associated with imaging correlates when restaging with computed tomography (CT), magnetic resonance imaging (MRI), or bone scintigraphy and, hence, were typically assumed to represent occult metastases. A rising prostate specific antigen (PSA) after previous local therapy prompting a PET scan showing uptake limited to regional lymph nodes is an increasingly common clinical scenario as advanced prostate cancer imaging becomes more widely utilized. The optimal management strategy for patients who have lymph node recurrent prostate cancer is both unclear and evolving, particularly in terms of local and regionally directed therapies. Stereotactic body radiation therapy (SBRT) utilizes ablative radiation doses with steep gradients to achieve local tumor control while sparing nearby normal tissues. SBRT is an attractive therapeutic modality due to its efficacy, favorable toxicity profile, and flexibility to administer elective doses to areas of potential occult involvement. The purpose of this review is to briefly describe how SBRT is being implemented in the era of PSMA PET for the management of solely lymph node recurrent prostate cancer.

RECENT FINDINGS

SBRT has been shown to effectively control individual lymph node tumor deposits within the pelvis and retroperitoneum for prostate cancer and is well-tolerated with a favorable toxicity profile. However, a major limitation thus far has been the lack of prospective trials supporting the use of SBRT for oligometastatic nodal recurrent prostate cancer. As further trials are conducted, its exact role in the treatment paradigm of recurrent prostate cancer will be better established. Although PET-guided SBRT appears feasible and potentially beneficial, there is still considerable uncertainty about the use of elective nodal radiotherapy (ENRT) in patients with nodal recurrent oligometastatic prostate cancer. PSMA PET has undoubtedly advanced imaging of recurrent prostate cancer, revealing anatomic correlates for disease recurrence that previously went undetected. At the same time, SBRT continues to be explored in prostate cancer with feasibility, a favorable risk profile, and satisfactory oncologic outcomes. However, much of the existing literature comes from the pre-PSMA PET era and integration of this novel imaging approach has led to greater focus on new and ongoing clinical trials to rigorously evaluate this approach and compare to other established treatment modalities utilized for oligometastatic, nodal recurrence of prostate cancer.

ACR Appropriateness Criteria® Post-Treatment Follow-up of Prostate Cancer: 2022 Update

Prostate cancer has a wide spectrum ranging between low-grade localized disease and castrate-resistant metastatic disease. Although whole gland and systematic therapies result in cure in the majority of patients, recurrent and metastatic prostate cancer can still occur. Imaging approaches including anatomic, functional, and molecular modalities are continuously expanding. Currently, recurrent and metastatic prostate cancer is grouped in three major categories: 1) Clinical concern for residual or recurrent disease after radical prostatectomy, 2) Clinical concern for residual or recurrent disease after nonsurgical local and pelvic treatments, and 3) Metastatic prostate cancer treated by systemic therapy (androgen deprivation therapy, chemotherapy, immunotherapy). This document is a review of the current literature regarding imaging in these settings and the resulting recommendations for imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

[Intermediate-risk prostate cancer treated with exclusive external irradiation: Focus on anatomical sites of recurrence in two French trials]

PURPOSE

Retrospective description of anatomical sites of relapse based on (18F)-choline PET-CT, (68Ga)-prostatic specific-membrane antigen PET-CT, bone scan, and prostate magnetic resonance imaging (MRI) data.

MATERIALS AND METHODS

From two French prospective cohorts, patients treated with exclusive radiotherapy for an intermediate-risk cancer were identified during their follow-ups. They were included if they presented a rising of the prostate-specific antigen (PSA) associated with the realization of an imaging showing the sites of recurrences.

RESULTS

Two hundred and sixty-three patients were included. After a median follow-up of 76 months (interquartile range [IQR] 67-95), 65 patients had biochemical recurrence and positive imaging. The median nadir PSA was 0.6ng/mL and the median PSA at recurrence was 3.4ng/mL. A single lesion was found in 48% of cases, 2 to 4 lesions in 43% of cases and more than 4 lesions in 9% of cases. The sites of relapse identified were prostate (37/65), prostate only (19/65), seminal vesicles (9/65) Pelvic nodes (35/65), extrapelvic nodes (15/65) and bone (13/65).

CONCLUSIONS

The majority of relapses presented as a single lesion localized in the pelvis.

Androgen Receptor Gene Pathway Upregulation and Radiation Resistance in Oligometastatic Prostate Cancer

Stereotactic ablative body radiotherapy (SABR) is currently used as a salvage intervention for men with oligometastatic prostate cancer (PC), and increasingly so since the results of the Stereotactic Ablative Body Radiotherapy for the Comprehensive Treatment of Oligometastatic Cancers (SABR-COMET) trial reported a significant improvement in overall survival with SABR. The addition of androgen deprivation therapy (ADT) to localised prostate radiotherapy improves survival as it sensitises PC to radiotherapy-induced cell death. The importance of the androgen receptor (AR) gene pathway in the development of resistance to radiotherapy is well established. In this review paper, we will examine the data to determine how we can overcome the upregulation of the AR pathway and suggest a strategy for improving outcomes in men with oligometastatic hormone-sensitive PC.

Mapping of Recurrence Sites Following Adjuvant or Salvage Radiotherapy for Prostate Cancer Patients

Introduction

Although salvage and adjuvant radiotherapy (RT) are effective in prostate cancer (PC) patients, 30%–40% of men will have disease progression. The objective was to describe the pattern of recurrence in PC patients with biochemical failure (BF) following postoperative RT.

Methods

We retrospectively analyzed 935 PC patients treated from 2009 to 2019 with adjuvant or salvage RT at the Institut de Cancérologie de l’Ouest. Of these, 205 (22%) developed BF of whom 166 underwent imaging. Patients with identified radiologic failure prior any specific treatment were included to determine the site of relapse categorized as local (L)-only, locoregional (LR), or metastatic (M) recurrence. Main disease characteristics and RT fields were examined in relation to sites of recurrence.

Results

One hundred forty-one patients were identified with 244 sites of failure on imaging. Of these, 108 patients had received RT to the PB alone and 33 RT to the PB and pelvic lymph nodes (PB+PLN). Androgen-deprivation therapy was used concomitantly in 50 patients (35%). The median PSA at imaging was 1.6 ng/ml (range, 0–86.7). In all, 74 patients (52%) had M disease (44% in the PB group and 79% in the PB+PLN group), 61 (43%) had LR failure (52% in the PB alone group and 15% in the PB+PLN group), and six (4%) had L-only failure, at a median of 26.7 months (range, 5–110.3) from RT. Metastases were in extra-pelvic LN (37 (15%)), bones (66 (27%)), and visceral organs (eight (3%)). Fifty-three (48%) of the pelvic LN failures in the PB group would have been encompassed by standard PLN RT volume.

Conclusion

We found that most patients evaluated for BF after postoperative RT recurred outside the RT field. Isolated pelvic nodal failure was rare in those receiving RT to the PB+PLN but accounted for half of failures in those receiving PB alone RT. Imaging directed salvage treatment could be helpful to personalize radiation therapy plan.

Patterns of Prostate Cancer Recurrence After Brachytherapy Determined by Prostate-Specific Membrane Antigen-Positron Emission Tomography and Computed Tomography Imaging

PURPOSE

The aim of this study was to characterize the patterns of prostate cancer recurrence after brachytherapy (BT) using 2-(3-[1-carboxy-5-([6-¹⁸F-fluoropyridine-3-carbonyl]-amino)-pentyl]-ureido)-pentanedioic acid ([¹⁸F]DCFPyL) prostate-specific membrane antigen (PSMA) positron emission tomography (PET) and computed tomography (CT) imaging.

METHODS AND MATERIALS

Patients were selected from an ongoing prospective institutional trial investigating the use of [¹⁸F]DCFPyL PSMA PET and CT in recurrent prostate cancer (NCT02899312). This report included patients who underwent BT (either monotherapy or boost) and experienced a biochemical failure (BF) defined by the Phoenix definition (prostate-specific antigen [PSA] > 2 ng/mL above nadir).

RESULTS

Between March 2017 and April 2020, 670 patients underwent [¹⁸F]DCFPyL PSMA PET and CT imaging. Of these 670 patients, 93 were treated with BT; 73 underwent monotherapy, and 20 underwent BT boost (19 low-dose rate and 1 high-dose rate). To report on patterns of recurrence outcomes, 86 patients (median prescan PSA 6.0) with a positive [¹⁸F]DCFPyL PSMA PET and CT scan and true BF were included. The most common location of relapse was local; 62.8% had a component of local failure (defined as prostate and/or seminal vesicles), and 46.5% had isolated local failure only, with no other sites of involvement. Regional failure occurred in 40.7% of patients, and 36.0% had metastatic failure. Isolated local recurrence was seen in 54.3% of monotherapy patients versus only in 12.5% of boost patients. Metastatic failure was seen in 28.6% of monotherapy patients versus 68.8% of the boost patients. Local recurrences (69.0%) were found within the same prostate biopsy sextant involved with the tumor at diagnosis, and 76.0% of patients with seminal vesicle recurrences had prostate-base involvement at diagnosis.

CONCLUSIONS

Contrary to previous evidence, our study suggests that in prostate BT patients with biochemical recurrence, the most common site of failure is local for the patients treated with monotherapy and metastatic for patients treated with a combination of external beam radiation and BT boost.

Prognostic factors, efficacy, and toxicity of involved-node stereotactic body radiation therapy for lymph node oligorecurrent prostate cancer : An investigation of 117 pelvic lymph nodes

BACKGROUND

The optimal radiotherapy regimen is not yet defined in the setting of oligorecurrent prostate cancer (oligorPC). There is evidence of high variability in treatment protocols among different centers worldwide, and no international consensus guidelines on treatment volumes, radiation schedules, and techniques. The purpose of the present retrospective study is to evaluate the efficacy and safety of involved-pelvic-node stereotactic body radiotherapy (SBRT) for oligorPC.

MATERIALS AND METHODS

Patients with pelvic node oligorPC following primary surgery, radical radiotherapy, or salvage radiotherapy for biochemical or local relapse of prostate cancer who underwent involved-node SBRT with biological effective dose (BED) > 100 Gy, with or without concurrent and adjuvant androgen deprivation therapy (ADT), were retrospectively evaluated. Biochemical progression-free survival (bPFS), distant progression-free survival (DPFS), overall survival (OS), possible prognostic factors, and toxicity outcomes were investigated.

RESULTS

From November 2012 to December 2019, 74 patients fitted the selection criteria. A total of 117 lesions were treated. Median follow-up was 31 months (range 6-89). Concurrent ADT was administered in 58.1% of patients. The 1‑year, 2‑year, and 3‑year DPFS was 77%, 37%, and 19%, respectively; the 1‑year, 2‑year, and 3‑year OS was 98%, 98%, and 95%, respectively. The presence of a single target lesion was associated with a statistically significant impact on OS. No in-field recurrence occurred. Patients who reached early prostate-specific antigen (PSA) nadir (< 3 months after SBRT) had a lower 3‑year survival (p = 0.004). The value of PSA nadir after SBRT and the time between primary treatment and SBRT had an impact on bPFS. Concomitant ADT was associated with improved DPFS. No acute or early late (> 6 months) genitourinary and gastrointestinal adverse events of any grade were reported, albeit with relatively short median follow-up.

CONCLUSION

SBRT is a safe and effective treatment for oligorPC, with a 100% local control rate in our series. It is not possible to clearly assess the opportunity to postpone ADT prescription in patients with two or more nodal metastases. The number of secondary lesions, time-to-nadir PSA, PSA nadir value, and the time interval between primary treatment and SBRT were identified as prognostic factors. Future prospective randomized studies are desirable to better understand the still open questions regarding the oligorecurrent prostate cancer state.

Unusual uptakes on 18F-fluorocholine positron emission tomography/computed tomography (PET/CT): a retrospective study of 368 prostate cancer patients referred for a biochemical recurrence or an initial staging

Background

¹⁸F-fluorocholine positron emission tomography/computed tomography (F-choline PET/CT) is considered a cornerstone in the staging and restaging of patients with prostate cancer (PCa). The aim of this study was to retrospectively assess unusual uptakes in patients who underwent a F-choline PET/CT for the initial staging or for the restaging of a relapsing PCa.

Methods

Three hundred and sixty-eight PCa patients were staged or restaged using F-choline PET/CT. Unusual uptakes were defined as uptakes occurring outside the usual paths of diffusion of PCa or as uptake in bone with a clear morphological evidence of nonmetastatic lesion.

Results

We found unusual uptakes in 47/368 patients (12.8%). Among them, 41/47 presented with benign F-choline uptake, usually within lymph nodes, due to inflammatory processes (22/47). Other benign processes were found in: thyroid (3/47), adrenal gland (3/47), brain (2/47), liver (1/47), bowel (3/47), frontal sinus (1/47), lungs (4/47), parotid gland (1/47) and bone (1/47). The six remaining patients presented with a second cancer, including lymphoma (1/47), non-small cell lung cancer (4/47) and neuroendocrine tumor (1/47).

Conclusions

unusual uptakes on F-choline PET/CT are quite frequent and should be explored since they may correspond to non-PCa.

Radiotherapy treatment volumes for oligorecurrent nodal prostate cancer: a systematic review

BACKGROUND

Radiotherapy is an emerging treatment strategy for nodal oligorecurrent prostate cancer (PCa) patients. However, large heterogeneities exist in the RT regimens used, with series reporting the use of elective nodal radiotherapy (ENRT) strategies and others the delivery of focal treatments to the relapsing nodes with Stereotactic Body Radiotherapy (SBRT). In this systematic review of the literature we compared the oncological outcomes and toxicity of the different RT regimens for nodal oligorecurrent PCa patients, with the aim of defining the optimal RT target volume in this setting.

METHODS

We performed a systemic search on the Pubmed database to identify articles reporting on the use of ENRT or SBRT for oligometastatic PCa with nodal recurrence.

RESULTS

Twenty-two articles were analyzed, including four prospective phase II trials (3 with SBRT and 1 with ENRT). Focal SBRT, delivered with an involved node, involved site, and involved field modality, was the most commonly used strategy with 2-year progression-free survival (PFS) rates ranging from 16 to 58% and a very low toxicity profile. Improved PFS rates were observed with ENRT strategies (52-80% at 3 years) compared to focal SBRT, despite a slightly higher toxicity rate. One ongoing randomized phase II trial is comparing both modalities in patients with nodal oligorecurrent PCa.

CONCLUSIONS

With a large variability in patterns of practice, the optimal RT strategy remains to be determined in the setting of nodal oligorecurrent PCa. Ongoing randomized trials and advances in translational research will help to shed light on the best management for these patients. .

Current Status of MRI and PET in the NCCN Guidelines for Prostate Cancer

Prostate cancer (PCa) represents a significant source of morbidity and mortality for men in the United States, with approximately 1 in 9 being diagnosed with PCa in their lifetime. The role of imaging in the evaluation of men with PCa has evolved and currently plays a central role in diagnosis, treatment planning, and evaluation of recurrence. Appropriate use of multiparametric MRI (mpMRI) and MRI-guided transrectal ultrasound (MR-TRUS) biopsy increases the detection of clinically significant PCa while decreasing the detection of clinically insignificant PCa. This process may help patients with clinically insignificant PCa avoid the adverse effects of unnecessary therapy. In the setting of a known PCa, patients with low-grade disease can be observed using active surveillance, which often includes a combination of prostate-specific antigen (PSA) testing, serial mpMRI, and, if indicated, follow-up systematic and targeted TRUS-guided tissue sampling. mpMRI can provide important information in the posttreatment setting, but PET/CT is creating a paradigm shift in imaging standards for patients with locally recurrent and metastatic PCa. This article examines the strengths and limitations of mpMRI for initial PCa diagnosis, active surveillance, recurrent disease evaluation, and image-guided biopsies, and the use of PET/CT imaging in men with recurrent PCa. The goal of this review is to provide a rational basis for current NCCN Clinical Practice Guidelines in Oncology for PCa as they pertain to the use of these advanced imaging modalities.

Role of Para-aortic Radiotherapy in the Management of Prostate Cancer

Recent studies assessing the patterns of failure following locoregional definitive therapy suggest that recurrences do happen in the adjacent most proximal drainage sites, not infrequently occurring within the common iliac and para-aortic regions. This pattern of recurrence and identification at initial presentation is being increasingly recognised using novel imaging techniques and there is limited evidence on how to manage these patients. We are awaiting definitive evidence regarding the clinical benefit of whole pelvic radiotherapy, and currently there is no consensus as to the optimal superior border. There is some acknowledgement that the superior border should encompass the common iliac nodal region. However, whether it should be extended even more proximally is currently unknown. Prospective randomised trials are required to determine if there is a role for extending the radiotherapy field in patients with or at high risk of para-aortic metastases.

Clinical perspectives from ongoing trials in oligometastatic or oligorecurrent prostate cancer: an analysis of clinical trials registries

PURPOSE

Thanks to the introduction of more sensitive/specific imaging and minimally invasive treatment techniques, the oligometastatic state in prostate cancer (PCa) has attracted the interest of the uro-oncological community. We aim to identify and analyze trials across five registries to gain insights into the directions this field is moving.

METHODS

A systematic review of trials on oligometastatic PCa registered on ClinicalTrials.gov, ANZCTR, ISRCTN, Netherlands and UMIN Clinical Trials Registries was performed using the following keywords: 'prostate cancer' and 'oligo'. Data were extracted from ongoing/completed trials, with an unreported primary endpoint in a peer-reviewed journal, as of May until August, 2018.

RESULTS

We identified 41 trials on oligometastatic PCa. Twenty-four trials are conducted in North America and 14 in Europe. Up to 70% are phase I or II trials and < 10% (n = 4) are in phase III. Less than 50% (n = 17) are randomized controlled trials. Oligometastases are PET detected in 25 trials. Studies on synchronous oligometastatic (n = 12; 29%) or oligorecurrent (n = 14; 34%) PCa are equally represented, the remainder focus on mixed states (n = 15; 37%). The majority (n = 39; 95%) of trials investigate local treatment options (RP: 5; RT: 9; RP ± RT: 7; metastasis-directed therapy: 28) with (72%) or without (28%) systemic treatment. The remaining two are imaging studies. Progression-free (PFS; 17/41; 41%) or overall survival (OS; 3/41; 7%) is defined as primary endpoint in half of all trials, others are 'safety/toxicity' or 'PSA response'.

CONCLUSIONS

With 41 ongoing trials, there is great interest in oligometastatic PCa. Most trials address local ablative treatments both for prostate and/or metastases, typically by radiotherapy, and several attempts to determine the benefit of adding systemic therapy. The field will hopefully have definitive answers after completion of four ongoing phase III trials.

11C-Choline PET/CT in Recurrent Prostate Cancer: Retrospective Analysis in a Large U.S. Patient Series

Our purpose was to evaluate the performance of ¹¹C-choline PET/CT in detecting biochemically recurrent prostate cancer (PCa) in a large non-European cohort (in the context of emerging evidence for prostate-specific membrane antigen PET in this setting) and to map patterns of PCa recurrence. Methods: We retrospectively analyzed ¹¹C-choline PET/CT scans from 287 patients who were enrolled in an imaging protocol based on rising prostate-specific antigen (PSA) levels (mean, 3.43 ng/mL; median, 0.94 ng/mL; range, 0.15-89.91 ng/mL) and suspected recurrent PCa. A total of 187 patients had undergone primary radical prostatectomy (RP) (79/187 had secondary radiotherapy), 30 had undergone primary radiotherapy, and 70 had a persistent PSA elevation after receiving initial treatment (69 after RP, 1 after radiotherapy). The level of suspicion for recurrence on ¹¹C-choline PET/CT was scored (0, negative; 1, equivocal; 2, positive) by 2 readers. The correlation between ¹¹C-choline PET/CT positivity and initial treatment, Gleason score, National Comprehensive Cancer Network stage, PSA level, PSA doubling time, PSA velocity, and time between initial treatment and PET imaging was evaluated. Prostate Cancer Molecular Imaging Standardized Evaluation (PROMISE) criteria were used to map ¹¹C-choline recurrence patterns. Results: Considering scores 1 and 2 as positives, consensus between the 2 readers deemed 66% of the ¹¹C-choline PET/CT scans as positive. When sorted by PSA level, 45% of patients with a PSA of less than 0.5 ng/mL, 56% of patients with a PSA of 0.5-0.99 ng/mL, 70% of patients with a PSA of 1.0-1.99 ng/mL, and 90% of patients with a PSA of at least 2.0 ng/mL scored either 1 or 2 on ¹¹C-choline PET/CT scans. When considering scores of 2 only, ¹¹C-choline PET/CT positivity was 54% (28%, 46%, 62%, and 81%, respectively, for patients with PSA < 0.5 ng/mL, 0.5-0.99 ng/mL, 1.0-1.99 ng/mL, and ≥ 2.0 ng/mL). In multivariate analysis, only PSA level was significantly associated with scan positivity. Pattern analysis showed that pelvic lymph nodes were the most common site of recurrence, and 28% of patients had ¹¹C-choline-positive suspected recurrences outside the initial treatment field. Conclusion: ¹¹C-choline PET/CT can detect PCa recurrence even among patients with low PSA levels when interpretation accounts for the clinical context, providing a certain pretest probability. Until prostate-specific membrane antigen agents are fully approved for PCa, choline PET/CT may provide clinical utility.

Magnetic Resonance-Guided Prostate Ablation

In 2019, the American Cancer Society (ACS) estimates that 174,650 new cases of prostate cancer will be diagnosed and 31,620 will die due to the prostate cancer in the United States. Prostate cancer is often managed with aggressive curative intent standard therapies including radiotherapy or surgery. Regardless of how expertly done, these standard therapies often bring significant risk and morbidity to the patient's quality of life with potential impact on sexual, urinary, and bowel functions. Additionally, improved screening programs, using prostatic-specific antigen and transrectal ultrasound-guided systematic biopsy, have identified increasing numbers of low-risk, low-grade "localized" prostate cancer. The potential, localized, and indolent nature of many prostate cancers presents a difficult decision of when to intervene, especially within the context of the possible comorbidities of aggressive standard treatments. Active surveillance has been increasingly instituted to balance cancer control versus treatment side effects; however, many patients are not comfortable with this option. Although active debate continues on the suitability of either focal or regional therapy for the low- or intermediate-risk prostate cancer patients, no large consensus has been achieved on the adequate management approach. Some of the largest unresolved issues are prostate cancer multifocality, limitations of current biopsy strategies, suboptimal staging by accepted imaging modalities, less than robust prediction models for indolent prostate cancers, and safety and efficiency of the established curative therapies following focal therapy for prostate cancer. In spite of these restrictions, focal therapy continues to confront the current paradigm of therapy for low- and even intermediate-risk disease. It has been proposed that early detection and proper characterization may play a role in preventing the development of metastatic disease. There is level-1 evidence supporting detection and subsequent aggressive treatment of intermediate- and high-risk prostate cancer. Therefore, accurate assessment of cancer risk (i.e., grade and stage) using imaging and targeted biopsy is critical. Advances in prostate imaging with MRI and PET are changing the workup for these patients, and advances in MR-guided biopsy and therapy are propelling prostate treatment solutions forward faster than ever.

11C-Choline PET Guided Salvage Radiation Therapy for Isolated Pelvic and Paraortic Nodal Recurrence of Prostate Cancer After Radical Prostatectomy: Rationale and Early Genitourinary or Gastrointestinal Toxicities

Purpose

To assess gastrointestinal (GI) and genitourinary (GU) adverse events (AEs) of ¹¹C-choline-positron emission tomography (CholPET) guided lymph node (LN) radiation therapy (RT) in patients who experience biochemical failure after radical prostatectomy.

Methods and Materials

From 2013 to 2016, 107 patients experienced biochemical failure of prostate cancer, had CholPET-detected pelvic and/or paraortic LN recurrence, and were referred for RT. Patients received androgen suppression and CholPET guided LN RT (median dose, 45 Gy) with a simultaneous integrated boost to CholPET-avid sites (median dose, 56.25 Gy), all in 25 fractions. RT-naïve patients had the prostatic fossa included in the initial treatment volumes followed by a sequential boost (median dose, 68 Gy). GI and GU AEs were reported per Common Terminology Criteria for Adverse Events (version 4.0) with data gathered retrospectively. Differences in maximum GI and GU AEs at baseline, immediately post-RT, and at early (median, 4 months) and late (median, 14 months) follow-up were assessed.

Results

Median follow-up was 16 months (interquartile range [IQR], 11-25). Median prostate-specific antigen at time of positive CholPET was 2.3 ng/mL (IQR, 1.3-4.8), with a median of 2 (IQR, 1-4) choline-avid LNs per patient. Most recurrences were within the pelvis (53%) or pelvis + paraortic (40%). Baseline rates of grade 1 to 2 GI AEs were 8.4% compared with 51.9% (4.7% grade 2) of patients post-RT (P < .01). These differences resolved by 4-month (12.2%, P = .65) and 14-month AE assessments (9.1%, P = .87). There was no significant change in grade 1 to 2 GU AEs post-RT (64.1%) relative to baseline (56.0%, P = .21), although differences did arise at 4-month (72.2%, P = .01) and 14-month (74.3%, P = .01) AE assessments.

Conclusions

Salvage CholPET guided nodal RT has acceptably low rates of acute GI and GU AEs and no significant detriment in 14-month GI AEs. These data are of value in counseling patients and designing prospective trials evaluating the oncologic efficacy of this treatment strategy.

68Ga-PSMA PET/CT in Patients with Rising Prostatic-Specific Antigen After Definitive Treatment of Prostate Cancer: Detection Efficacy and Diagnostic accuracy

RATIONALE AND OBJECTIVES

⁶⁸Ga-prostate-specific membrane antigen-11 (⁶⁸Ga-PSMA-11) is a recently developed positron emission tomography (PET) tracer that can detect prostate cancer (PC) relapses and metastases with high contrast resolution. The aim of this study was to assess the detection efficacy and diagnostic accuracy of ⁶⁸Ga-PSMA PET/CT image in patients with rising prostatic-specific antigen (PSA) after treatment of PC.

MATERIALS AND METHODS

The present prospective study included 188 patients who exhibited rising of PSA level on a routine follow-up examination after definitive treatment of PC. All patients underwent a ⁶⁸Ga-PSMA PET/CT examination. For each patient, we determined the disease stage, the Gleason score, and the maximum standardized uptake value of the local recurrence and extraprostatic metastases. The detection efficacy and diagnostic accuracy of ⁶⁸Ga-PSMA PET/CT were established by histopathology and clinical and imaging follow-up as the reference standards.

RESULTS

⁶⁸Ga-PSMA PET/CT detected tumour relapse in 165 patients (35 patients had local recurrence, 106 patients had extraprostatic metastases, and 24 patients had combined lesions). The sensitivity, specificity, and accuracy values of ⁶⁸Ga-PSMA PET/CT examination in the detection of PC recurrence were 98.8%, 100%, and 98.8%, respectively. ⁶⁸Ga-PSMA PET/CT revealed an overall detection rate of 87.8% (165/188) in patients with rising PSA (median of 2.2 ng/mL, and range of 0.01-70 ng/mL).

CONCLUSION

⁶⁸Ga-PSMA PET/CT is a valuable tool for the detection of PC local recurrence or extraprostatic metastases following rising PSA levels after primary definitive therapy and should be incorporated during routine work-up.

Pattern of metastatic deposit in recurrent prostate cancer: a whole-body MRI-based assessment of lesion distribution and effect of primary treatment

PURPOSE

It is generally accepted that when metastases develop in a patient with biochemical recurrence of prostate cancer (PCa), they follow a centrifuge pattern of seeding from the pelvis and that most patients enter the disease as oligometastatic. In this study, we used whole-body magnetic resonance imaging (WB-MRI) to assess the anatomical distribution of oligo- and polymetastatic disease and the impact of the initial treatment on this distribution in patients.

MATERIALS AND METHODS

WB-MRI examinations of patients with a rising prostate-specific antigen (PSA) after radical treatment by surgery or/and radiotherapy were analyzed for disease recurrence. The patients were separated into three groups, based on the primary treatment: patients treated by radical prostatectomy without radiotherapy and with/without lymph node dissection (RP), patients treated only by radiotherapy or hormono-radiotherapy (RT) and patients treated with radical prostatectomy and adjuvant or salvage radiotherapy (RP + RT). Patients with ≤ 5 bone or/and node metastases were considered oligometastatic. Regional distributions of bone and lymph nodes metastases were reported using anatomical diagrams. Univariate and multivariable logistic regressions were performed to identify prognostic factors of relapse.

RESULTS

The primary treatment (RP, RT, RP + RT), Gleason score, PSA at relapse, time between first diagnosis and recurrence did not influence the metastatic status (oligo vs. polymetastatic). Oligometastatic patients showed different distribution of bone metastases compared to the polymetastatic ones and the distribution of the oligometastatic disease was not influenced by the primary treatment.

CONCLUSIONS

In this WB-MRI-based study, there was no evidence that the primary treatment influenced the metastatic status of the patient or the distribution of the oligometastatic disease.

Percutaneous Image-Guided Nodal Biopsy After 11C-Choline PET/CT for Biochemically Recurrent Prostate Cancer: Imaging Predictors of Disease and Clinical Implications

Purpose

Management of recurrent prostate cancer necessitates timely diagnosis and accurate localization of the sites of recurrent disease. The purpose of this study was to assess predictors of histologic outcomes after 11C-choline positron emission tomography/computed tomography (CholPET) to increase the positive predictive value and specificity of CholPET in identifying imaging predictors of malignant and benign nodal disease to better inform clinical decision making regarding local therapy planning.

Materials and Methods

Retrospective review of patients undergoing CholPET followed by percutaneous core needle biopsy between January 1, 2010 and January 1, 2016. A total of 153 patients were identified who underwent 166 biopsy procedures. Patient, CholPET, procedural, and pathologic characteristics were recorded.

Results

A total of 157 biopsies were technically successful, and 110 (70.1%; 95% confidence interval, 62.2-77.1) yielded histologic results abnormal for metastatic prostate cancer. Lesion location, lesion maximum standardized uptake value (SUVmax), SUV ratio (calculated as the ratio of SUVmax to SUV mean in the right atrium), prostate-specific antigen, lesion short axis length, total Gleason score, and castration resistance were all associated with abnormal biopsy results (P values <.001, <.001, <.001, .02, .02, .02, and .015, respectively). External iliac, common iliac, and inguinal sites were associated with much lower rates of histologic positivity (mean [95% confidence interval], 51.2% [35.1-67.1], 46.2% [19.2-74.9], and 33.3% [7.5-70.1]), respectively.

Conclusions

In a cohort of patients in whom core needle biopsy was performed after CholPET, characteristics of choline localization including node location, SUVmax, lesion–to–blood pool SUV ratio, prostate-specific antigen, total Gleason score, and castration resistance were significantly associated with abnormal biopsy results for metastatic disease on CholPET. Relatively high false positive rates were found in common iliac, external iliac, and inguinal lymph node locations. Histologic confirmation of these sites should be strongly considered in the appropriate clinical scenario before designing additional local therapy plans.

Contemporary update of overall prognosis and nomogram to predict individualized survival for Chinese patients with eyelid sebaceous carcinoma

Background

The prognosis of Chinese patients with eyelid sebaceous carcinoma (SC) has not been updated for >3 decades. The prognostic predictors are multifactorial, and there is no validated prognostic model for eyelid SC.

Methods

This study included 238 consecutive patients with eyelid SC. All eligible patients were followed up for metastasis and mortality. The predictors of tumor-related survival were explored by Cox analyses. A prognostic nomogram was developed and validated using bootstrap resampling. The predictive accuracy and discriminative ability were compared between the nomogram and the Tumor, Node, Metastasis (TNM) staging system.

Findings

After a median follow-up period of 55.5 months, 27 (11.3%) patients died of metastatic SC, with a median survival time of 48.0 months. The 5-year and 10-year tumor-related survival rates were 88.1% and 77.9%, respectively. Orbital involvement (HR: 3.11, p = .022), the greatest tumor basal diameter (HR: 1.06, p = .003), the presence of pagetoid spread (HR: 2.90, p = .017), and having lymph node metastasis at initial diagnosis (HR: 13.66, p < .001) were independent risk factors for tumor-related death. A nomogram integrating these 4 factors was developed with a C-index of 0.887, which is significantly better than that of the TNM staging system (p = .002). The risk groups stratified by nomogram scores (p < .001 (low vs intermediate risk); p = .001 (intermediate vs high risk)) displayed better discrimination ability than TNM staging (T1 vs T2: p = .358; T2 vs T3: p = .171; T3 vs T4: p < .001) in patients at an early stage.

Interpretation

The prognosis of Chinese patients with eyelid SC has improved over the last 3 decades, and it is comparable to that of patients from other countries. This nomogram provides more accurate individualized estimates of survival for eyelid SC patients and may guide clinicians in their therapeutic decisions.

Prospective Immunophenotyping of CD8+ T Cells and Associated Clinical Outcomes of Patients With Oligometastatic Prostate Cancer Treated With Metastasis-Directed SBRT

PURPOSE

This study examined the effects of metastasis-directed stereotactic body radiation therapy (mdSBRT) on CD8⁺ T-cell subpopulations and correlated post-mdSBRT immunophenotypic responses with clinical outcomes in patients with oligometastatic prostate cancer (OPCa).

METHODS AND MATERIALS

Peripheral blood mononuclear cells were prospectively isolated from 37 patients with OPCa (≤3 metastases) who were treated with mdSBRT. Immunophenotyping identified circulating CD8⁺ T-cell subpopulations, including tumor-reactive (T_TR), effector memory, central memory (T_CM), effector, and naïve T cells from samples collected before and after mdSBRT. Univariate Cox proportional hazards regression was used to assess whether changes in these T-cell subpopulations were potential risk factors for death and/or progression. The Kaplan-Meier method was used for survival. Cumulative incidence for progression and new distant metastasis weas estimated, considering death as a competing risk.

RESULTS

Median follow-up was 39 months (interquartile range, 34-43). Overall survival at 3 years was 78.2%. Cumulative incidence for local progression and new distant metastasis at 3 years was 16.5% and 67.6%, respectively. Between baseline and day 14 after mdSBRT, an increase in the T_CM cell subpopulation was associated with the risk of death (hazard ratio, 1.22 [95% confidence interval, 1.02-1.47]; P = .033), and an increase in the T_TR cell subpopulation was protective against the risk of local progression (hazard ratio, 0.80 [95% confidence interval, 0.65-0.98]; P = .032).

CONCLUSIONS

An increase in the T_TR cell subpopulation was protective against the risk of disease progression, and an increase in the T_CM cell subpopulation was associated with the risk of death in patients with OPCa treated with mdSBRT. Disease control may be further improved by better understanding the CD8⁺ T-cell subpopulations and by enhancing their antitumor effect.

The utility of PET-based imaging for prostate cancer biochemical recurrence: a systematic review and meta-analysis

INTRODUCTION

Conventional imaging modalities have been poor in characterizing the true extent of disease in men with biochemical recurrence following primary treatment for prostate cancer. Functional imaging with positron emission tomography (PET) has shown promise of being a superior imaging modality. We conducted a systematic review and meta-analysis to define the diagnostic accuracy of PET/CT using 11C-choline, 18F-FACBC, or 68Ga-PSMA in detecting recurrent prostate cancer.

METHODS

We searched multiple databases in line with the preferred reporting items for systematic review and meta-analysis (PRISMA) statement to define the diagnostic accuracy of 11C-choline, 18F-FACBC, or 68Ga-PSMA PET/CT. Only studies secondarily staging participants with biochemical recurrence and those with an appropriate reference standard (pathology, further imaging, and/or clinical response) were eligible for analysis.

RESULTS

Twenty-one studies with 3202 participants met the inclusion criteria. Of these, 11C-choline, 18F-FACBC, and 68Ga-PSMA were the tracer investigated in 16, 5, and 1 studies, respectively. The summary sensitivity for each tracer was 80.9% (95% CI 70.4-88.3%), 79.7% (95% CI 51.9-93.4%), and 76.4% (95% CI 68.3-82.9%), respectively. The corresponding summary specificity was 84.1% (95% CI 70.2-92.2%), 61.9% (95% CI 41.1-79.0%), and 99.8% (95% CI 97.5-100%), respectively. Detection rates ranged between 58.6 and 82.8%. All included studies were judged to be at high risk of bias primarily due to study limitations pertaining to the reference standard.

CONCLUSION

There is a lack of high-quality data to verify the accuracy of PET-based imaging using 11C-choline, 18F-FACBC, or 68Ga-PSMA. The early results are encouraging that these techniques are superior to conventional imaging modalities, which would allow salvage therapies to be optimized.

MR-Guided Prostate Interventions

Prostate cancer is the most commonly diagnosed noncutaneous cancer and second leading cause of death in men. Many patients with clinically organ-confined prostate cancer undergo definitive treatment of the whole gland, including radical prostatectomy, radiation therapy, and cryosurgery. Active surveillance is a growing alternative option for patients with documented low-volume and low-grade prostate cancer. However, many patients are wanting a less morbid focal treatment alternative. With recent advances in software and hardware of magnetic resonance imaging (MRI), multiparametric MRI of the prostate has been shown to improve the accuracy in detecting and characterizing clinically significant prostate cancer. Targeted biopsy is increasingly utilized to improve the yield of MR detected, clinically significant prostate cancer and to decrease in detection of indolent prostate cancer. MR-guided targeted biopsy techniques include cognitive MR fusion transrectal ultrasound (TRUS) biopsy, in-bore transrectal targeted biopsy using robotic transrectal device, and in-bore direct MR-guided transperineal biopsy with a software based transperineal grid template. In addition, advances in MR-compatible thermal ablation technology allow accurate focal or regional delivery of thermal ablative energy to the biopsy-proved, MRI-detected tumor. MR-guided ablative treatment options include cryoablation, laser ablation, and high-intensity focused ultrasound with real-time or near simultaneous monitoring of the ablation zone. We present a contemporary review of MR-guided techniques for prostatic interventions.

Oligometastatic prostate cancer and salvage lymph node dissection: systematic review

INTRODUCTION

We provide a comprehensive description of the physio-pathological theories behind oligometastatic prostate cancer (PCa) and analyze modern imaging techniques, presenting a systematic review of the available evidences regarding salvage lymph node dissection (sLND).

EVIDENCE ACQUISITION

A systematic review was attempted. The PubMed/Medline database was searched for "salvage" AND ("lymph node dissection" OR "lymphadenectomy") AND "prostate" AND "cancer." Only English publications were targeted. Relevant original articles addressing the role of sLND in PCa were selected.

EVIDENCE SYNTHESIS

Biochemical response (BR) was reported in 10-79.5% of the cases overall. These results were not durable and biochemical recurrence occurred in 54.5-93.8% of the cases, within 5 years. Furthermore, 50-80% of patients received some kind of adjuvant treatment right after sLND, regardless post-operative prostate-specific antigen levels. Surgery-related morbidity was low, with a 0-27% incidence of Clavien-Dindo III complications. No sLND-related deaths were observed.

CONCLUSIONS

sLND is not associated with a durable response over time but may postpone HT and its related complications, in selected patients. Although a limited morbidity was reported, sLND remains technically demanding and a careful selection of patients is advisable.

Oligorecurrent prostate cancer limited to lymph nodes: getting our ducks in a row : Nodal oligorecurrent prostate cancer

PURPOSE

Oligorecurrent prostate cancer with exclusive nodal involvement represents a common state of disease, amenable to local therapy. New radio-labeled tracers have enriched the possibility of cancer detection and treatment. In this review, we aim to illustrate the main nuclear medicine diagnostic options and the role of radiotherapy in this setting of patients.

METHODS

We performed a PubMed search referring to the PRISMA guidelines to analyze the performance of PSMA- and choline-PET in detecting oligorecurrence limited to lymph nodes, and to review the main studies supporting either ablative stereotactic body radiotherapy or regional lymph node irradiation in this clinical setting.

RESULTS

PSMA-PET has shown higher efficacy in the diagnosis of nodal lesions if compared with choline-PET. More specifically, for PSA ≤ 2 ng/ml, the median detection rate of choline-PET ranges from 19.5 to 44.5%, whereas PSMA ranges from 51.5 to 74%. SBRT achieves high local control rates positively affecting progression-free survival (PFS), with androgen deprivation therapy (ADT)-free survival ranging from 25 to 44 months and with low toxicity rates (0-15%). Prophylactic nodal irradiation shows 3-year PFS rates ranging from 62 to 75%, but with a potential higher risk of toxicity. However, the chosen treatment option needs to be tailored on the single patient.

CONCLUSIONS

Newer PET/CT radio-labeled tracers have increased disease detection in oligorecurrent prostate cancer patients. Growing evidence of their impact on metastasis-directed therapy encourages the use of the most advanced radiotherapy techniques in the clinical management of such patients.

Prediction models for prostate cancer outcomes: what is the state of the art in 2017?

PURPOSE OF REVIEW

Prostate cancer (PCa) remains a significant public health burden, with multiple points for decision-making at all stages of the disease. Given the amount and variety of data that may influence disease management, prediction models have been published to assist clinicians and patients in making decisions about the best next course of action at many disease states. We sought to review the most important studies related to PCa prediction models since 2016 and evaluate their impact upon the evolving field of risk modeling in PCa.

RECENT FINDINGS

There has been a significant amount of work published in the past year concerning risk modeling in PCa at all stages of disease, ranging from screening to predicting survival with metastatic disease. The majority of recent publications focus upon the addition of a new biomarker to prediction models or upon validating previously published prediction models. In particular, MRI has been the topic of a number of more recent studies.

SUMMARY

Prediction modeling in PCa currently compares the area under the receiver operating curve between models with and without the biomarker of interest to predict the outcome of interest in multiple disease states, ranging from diagnosis to prediction of survival with metastatic disease. Future work should provide additional information regarding clinical impact and measures of prediction confidence.

Standard of Care Versus Metastases-directed Therapy for PET-detected Nodal Oligorecurrent Prostate Cancer Following Multimodality Treatment: A Multi-institutional Case-control Study

BACKGROUND

Most prostate cancer (PCa) patients with a biochemical failure following primary multimodality treatment (surgery and postoperative radiotherapy) relapse in the nodes.

OBJECTIVE

To perform a matched-case analysis in men with lymph node recurrent PCa comparing standard of care (SOC) with metastasis-directed therapy (MDT).

DESIGN, SETTING, AND PARTICIPANTS

PCa patients with a prostate-specific antigen (PSA) progression following multimodality treatment were included in this retrospective multi-institutional analysis.

INTERVENTION

The SOC cohort (n=1816) received immediate or delayed androgen deprivation therapy administered at PSA progression. The MDT cohort (n=263) received either salvage lymph node dissection (n=166) or stereotactic body radiotherapy (n=97) at PSA progression to a positron emission tomography-detected nodal recurrence.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint, cancer-specific survival (CSS), was analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards models, and propensity score-matched analyses.

RESULTS AND LIMITATIONS

At a median follow-up of 70 (interquartile range: 48-98) mo, MDT was associated with an improved CSS on univariate (p=0.029) and multivariate analysis (hazard ratio: 0.33, 95% confidence interval [CI]: 0.17-0.64) adjusted for the year of radical prostatectomy (RP), age at RP, PSA at RP, time from RP to PSA progression, Gleason score, surgical margin status, pT- and pN-stage. In total, 659 men were matched (3:1 ratio). The 5-yr CSS was 98.6% (95% CI: 94.3-99.6) and 95.7% (95% CI: 93.2-97.3) for MDT and SOC, respectively (p=0.005, log-rank). The main limitations of our study are its retrospective design and lack of standardization of systemic treatment in the SOC cohort.

CONCLUSIONS

MDT for nodal oligorecurrent PCa improves CSS as compared with SOC. These retrospective data from a multi-institutional pooled analysis should be considered as hypothesis-generating and inform future randomized trials in this setting.

PATIENT SUMMARY

Prostate cancer patients experiencing a lymph node recurrence might benefit from local treatments directed at these lymph nodes.

Prognostic Value of [18F]-Fluoromethylcholine Positron Emission Tomography/Computed Tomography Before Stereotactic Body Radiation Therapy for Oligometastatic Prostate Cancer

PURPOSE

To investigate the predictive value of [¹⁸F]-fluoromethylcholine positron emission tomography/computed tomography (PET/CT)-derived parameters on progression-free survival (PFS) in oligometastatic prostate cancer patients treated with stereotactic body radiation therapy (SBRT).

METHODS AND MATERIALS

In [¹⁸F]-fluoromethylcholine PET/CT scans of 40 consecutive patients with ≤4 metachronous metastases treated with SBRT we retrospectively measured the number of metastases, standardized uptake values (SUV_mean, SUV_max, SUV_peak), metabolically active tumor volume (MATV), and total lesion choline uptake. Partial-volume correction was applied using the iterative deconvolution Lucy-Richardson algorithm.

RESULTS

Thirty-seven lymph node and 13 bone metastases were treated with SBRT. Thirty-three patients (82.5%) had 1 lesion, 4 (10%) had 2 lesions, and 3 (7.5%) had 3 lesions. After a median follow-up of 32.6 months (interquartile range, 35.5 months), the median PFS was 11.5 months (95% confidence interval 8.4-14.6 months). Having more than a single metastasis was a significant prognostic factor (hazard ratio 2.74; P = .03), and there was a trend in risk of progression for large MATV (hazard ratio 1.86; P = .10). No SUV or total lesion choline uptake was significantly predictive for PFS, regardless of partial-volume correction. All PET semiquantitative parameters were significantly correlated with each other (P ≤ .013).

CONCLUSIONS

The number of choline-avid metastases was a significant prognostic factor for progression after [¹⁸F]-fluormethylcholine PET/CT-guided SBRT for recurrent oligometastatic prostate cancer, and there seemed to be a trend in risk of progression for patients with large MATVs. The lesional level of [¹⁸F]-fluoromethylcholine uptake was not prognostic for progression.

Surveillance or Metastasis-Directed Therapy for Oligometastatic Prostate Cancer Recurrence: A Prospective, Randomized, Multicenter Phase II Trial

Purpose Retrospective studies suggest that metastasis-directed therapy (MDT) for oligorecurrent prostate cancer (PCa) improves progression-free survival. We aimed to assess the benefit of MDT in a randomized phase II trial. Patients and Methods In this multicenter, randomized, phase II study, patients with asymptomatic PCa were eligible if they had had a biochemical recurrence after primary PCa treatment with curative intent, three or fewer extracranial metastatic lesions on choline positron emission tomography-computed tomography, and serum testosterone levels > 50 ng/mL. Patients were randomly assigned (1:1) to either surveillance or MDT of all detected lesions (surgery or stereotactic body radiotherapy). Surveillance was performed with prostate-specific antigen (PSA) follow-up every 3 months, with repeated imaging at PSA progression or clinical suspicion for progression. Random assignment was balanced dynamically on the basis of two factors: PSA doubling time (≤ 3 v > 3 months) and nodal versus non-nodal metastases. The primary end point was androgen deprivation therapy (ADT)-free survival. ADT was started at symptomatic progression, progression to more than three metastases, or local progression of known metastases. Results Between August 2012 and August 2015, 62 patients were enrolled. At a median follow-up time of 3 years (interquartile range, 2.3-3.75 years), the median ADT-free survival was 13 months (80% CI, 12 to 17 months) for the surveillance group and 21 months (80% CI, 14 to 29 months) for the MDT group (hazard ratio, 0.60 [80% CI, 0.40 to 0.90]; log-rank P = .11). Quality of life was similar between arms at baseline and remained comparable at 3-month and 1-year follow-up. Six patients developed grade 1 toxicity in the MDT arm. No grade 2 to 5 toxicity was observed. Conclusion ADT-free survival was longer with MDT than with surveillance alone for oligorecurrent PCa, suggesting that MDT should be explored further in phase III trials.

11C-Choline-Pet Guided Stereotactic Body Radiation Therapy for Lymph Node Metastases in Oligometastatic Prostate Cancer

INTRODUCTION

aim is outcome of 11C-Choline-PET guided SBRT on lymph node metastases.

MATERIALS AND METHODS

patients with 1 - 4 lymph node metastases detected by 11C-choline-PET were treated with SBRT. Toxicity, treated metastases control and Progression Free Survival were computed.

RESULTS

twenty-six patients, 38 lymph node metastases were irradiated. No grade ≥ 2 toxicity. Median PSA-nadir after RT was 1.02 ng/mL. Post-treatment 11C-Choline-PET showed metabolic complete response in 17 metastases (44,7%), partial response in 9 metastases (38%).

CONCLUSION

SBRT is effective and safe for lymph node metastases. PET is important in identification of gross tumor and evaluation of the response.

Prevalence and prognosis of low-volume, oligorecurrent, hormone-sensitive prostate cancer amenable to lesion ablative therapy

OBJECTIVES

To describe the anatomical patterns of prostate cancer (PCa) recurrence after primary therapy and to investigate if patients with low-volume disease have a better prognosis as compared with their counterparts.

MATERIALS AND METHODS

Patients eligible for an 18-F choline positron-emission tomography (PET)-computed tomography (CT) were enrolled in a prospective cohort study. Eligible patients had asymptomatic biochemical recurrence after primary PCa treatment and testosterone levels >50 ng/mL. The number of lesions was counted per scan. Patients with isolated local recurrence (LR) or with ≤3 metastases (with or without LR) were considered to have low-volume disease and patients with >3 metastases to have high-volume disease. Descriptive statistics were used to report recurrences. Cox regression analysis was used to investigate the influence of prognostic variables on the time to developing castration-resistant PCa (CRPC).

RESULTS

In 208 patients, 625 sites of recurrence were detected in the lymph nodes (N1/M1a: 30%), the bone (18%), the prostate (bed; 11%), viscera (4%), or a combination of any of the previous (37%). In total, 153 patients (74%) had low-volume recurrence and 55 patients (26%) had high-volume recurrence. The 3-year CRPC-free survival rate for the whole cohort was 79% (95% confidence interval 43-55), 88% for low-volume recurrences and 50% for high-volume recurrences (P < 0.001). Longer PSA doubling time at time of recurrence and low-volume disease were associated with a longer time to CRPC.

CONCLUSIONS

Three out of four patients with PCa with a 18-F choline PET-CT-detected recurrence have low-volume disease, potentially amenable to local therapy. Patients with low-volume disease have a better prognosis as compared with their counterparts. Lymph node recurrence was the most dominant failure pattern.

Prognostic significance of long noncoding RNA Z38 as a candidate biomarker in breast cancer

BACKGROUND

Long noncoding RNA (lncRNA) Z38 has been shown to promote cell proliferation and tumorigenesis in breast cancer. However, expression pattern and prognostic value of lncRNA Z38 in breast cancer patients remain elusive.

METHODS

The expression levels of SPRY4-IT1 in 110 self-paired specimens of breast cancer and adjacent normal breast tissues were measured by quantitative real-time PCR (qRT-PCR), and its correlation with overall survival of patients with breast cancer was further statistically analyzed.

RESULTS

Compared with normal breast tissues, Z38 was upregulated in breast cancer tissues. Furthermore, of 110 breast cancer patients, high Z38 expression was significantly associated with tumor-node-metastasis stage and lymph node metastasis. Further analysis using the Cox regression model revealed that Z38 expression was an independent prognostic factor of overall survival in patients with breast cancer (hazard ratio=4.74, 95% confidence interval 2.41-9.32). The nomogram presents a good prediction of the probability of overall survival of breast cancer patients (c-index: 0.792), and its predictive efficiency was further confirmed by the calibration curve.

CONCLUSION

Our data highlighted the potential of lncRNA Z38 as novel candidate biomarker to identify patients with breast cancer at high risk of tumor death.

Patterns of Recurrence After Postprostatectomy Fossa Radiation Therapy Identified by C-11 Choline Positron Emission Tomography/Computed Tomography

PURPOSE

To evaluate C-11 choline positron emission tomography/computed tomography (CholPET) in staging and determining patterns of recurrence in prostate cancer patients with rising prostate-specific antigen levels after prostatectomy radiation therapy (RT).

METHODS AND MATERIALS

The study includes patients with biochemical failure after postprostatectomy RT who underwent CholPET between 2008 and 2015. Patient and disease characteristics were examined in relation to sites of recurrence. All RT dosimetry records were reviewed, and recurrences were mapped on a representative computed tomography dataset with their relationship relative to the irradiated fossa field as out of field (OOF), edge of field (EOF; recurrence within <45-Gy isodose lines), or in field (IF; recurrence within ≥45-Gy isodose lines).

RESULTS

Forty-one patients were identified with 121 sites of recurrence (median 2 sites; interquartile range [IQR], 1-4). The median prostate-specific antigen level at CholPET was 3.1 (IQR, 1.9-5.6) ng/mL. Median interval from RT to biochemical failure was 24 (IQR, 10-46) months, with recurrence identified on CholPET at a median of 15 (IQR, 7-28) months from biochemical failure. Histologic confirmation of recurrence was obtained in 20 patients (49%), with the remainder confirmed by treatment response. Five patients (12%) had IF recurrences, 10 patients (24%) had EOF recurrences (median dose 10 Gy; IQR, 5-30 Gy), and 36 patients (88%) had OOF recurrences. Ten patients had combination failures: 6 (15%) EOF/OOF and 4 (10%) IF/OOF. Fifty-seven recurrences (47%) were pelvic nodal sites inferior to the L5-S1 interspace, of which 52 (43%) were within a pelvic RT field. Eighty-one recurrences (67%) were nodal and inferior to the aortic bifurcation.

CONCLUSIONS

Using CholPET, we found that the majority of patients evaluated for biochemical failure recurred outside of the postprostatectomy RT field. Furthermore, most recurrence sites were nodal and inferior to the aortic bifurcation. These results provide data that may be useful for examining strategies that include elective lymph node irradiation in postprostatectomy patients.