Randomized phase 2 trial of tremelimumab and durvalumab in combination versus sequentially in recurrent platinum-resistant ovarian cancer

BACKGROUND

Single-agent immune checkpoint inhibitors (ICIs) have demonstrated limited responses in recurrent ovarian cancer; however, 30%-40% of patients achieve stable disease. The primary objective was to estimate progression-free survival (PFS) after sequential versus combination cytotoxic T-lymphocyte antigen 4 and programmed death ligand 1 ICIs in patients with platinum-resistant high-grade serous ovarian cancer (HGSOC).

METHODS

Patients were randomized to a sequential arm (tremelimumab followed by durvalumab on progression) or a combination arm (tremelimumab plus durvalumab, followed by durvalumab) via a Bayesian adaptive design that made it more likely for patients to be randomized to the more effective arm. The primary end point was immune-related PFS (irPFS).

RESULTS

Sixty-one subjects were randomized to sequential (n = 38) or combination therapy (n = 23). Thirteen patients (34.2%) in the sequential arm received durvalumab. There was no difference in PFS in the sequential arm (1.84 months; 95% CI, 1.77-2.17 months) compared with the combination arm (1.87 months; 95% CI, 1.77-2.43 months) (p = .402). In the sequential arm, no responses were observed, although 12 patients (31.6%) demonstrated stable disease. In the combination arm, two patients (8.7%) had partial response, whereas one patient (4.4%) had stable disease. Adverse events were consistent with those previously reported for ICIs. Patient-reported outcomes were similar in both arms.

CONCLUSIONS

There was no difference in irPFS for combination tremelimumab plus durvalumab compared to tremelimumab alone (administered as part of a sequential treatment strategy) in a heavily pretreated population of patients with platinum-resistant HGSOC. Response rates were comparable to prior reports, although the combination regimen did not add significant benefit, as has been previously described.

Surgical Management and Considerations for Patients with Localized High-Risk Prostate Cancer

OPINION STATEMENT

Localized high-risk (HR) prostate cancer (PCa) is a heterogenous disease state with a wide range of presentations and outcomes. Historically, non-surgical management with radiotherapy and androgen deprivation therapy was the treatment option of choice. However, surgical resection with radical prostatectomy (RP) and pelvic lymph node dissection (PLND) is increasingly utilized as a primary treatment modality for patients with HRPCa. Recent studies have demonstrated that surgery is an equivalent treatment option in select patients with the potential to avoid the side effects from androgen deprivation therapy and radiotherapy combined. Advances in imaging techniques and biomarkers have also improved staging and patient selection for surgical resection. Advances in robotic surgical technology grant surgeons various techniques to perform RP, even in patients with HR disease, which can reduce the morbidity of the procedure without sacrificing oncologic outcomes. Clinical trials are not only being performed to assess the safety and oncologic outcomes of these surgical techniques, but to also evaluate the role of surgical resection as a part of a multimodal treatment plan. Further research is needed to determine the ideal role of surgery to potentially provide a more personalized and tailored treatment plan for patients with localized HR PCa.

Peripheral T-Cell Priming and Micrometastatic Disease Control with Metastasis-Directed Therapy: Multidimensional Immunogenomic Profiling of Oligometastatic Prostate Cancer in the EXTEND Trial

PURPOSE/OBJECTIVE(S)

Comprehensive metastasis-directed therapy (MDT) for oligometastatic prostate cancer extended progression-free survival (PFS) and time to new lesion formation in the intermittent hormone therapy (HT) basket of EXTEND. To better understand the mechanism of MDT benefit, we pooled the intermittent and continuous HT baskets of EXTEND and tested the hypothesis that adding MDT to HT would program systemic T-cells to control micrometastatic disease.

MATERIALS/METHODS

A total of 174 men were randomized to HT with or without MDT to up to 5 sites of metastases. HT was given for 6 months (intermittent basket, n = 87) or indefinitely (continuous basket, n = 87). Peripheral blood samples were drawn at enrollment, at the end of MDT, at 3 months follow-up (3 mo F/U), and at progression and then analyzed by flow cytometry, T-cell receptor (TCR)-β CDR3 variable region sequencing, multiplex cytokine profiling, and next-generation circulating tumor DNA (ctDNA) sequencing. TCR clonal expansion was determined using a published betabinomial model. Repertoire changes were assessed by Morisita's index, and dominant TCR repertoire motifs were characterized with ImmunoMap. Associations between blood markers and PFS were evaluated with Cox regression adjusted hazard ratios (aHR) accounting for randomization arm and stratifying for intermittent vs continuous HT.

RESULTS

Randomization to MDT+HT was associated with T-cell activation, proliferation, and clonal expansion. This response was first observed at end-MDT as upregulated expression of T-cell activation and inhibition markers (i.e., ICOS, Tim-3, and LAG-3) and increases in highly proliferative CD4+ and CD8+ Ki67hi T-cells (all P<0.05). TCR sequencing of 7,678,911 T-cells revealed that MDT+HT was associated with TCR clonal expansion, remodeling of the TCR repertoire, and changes in dominant TCR motifs at end-MDT and 3 mo F/U (all P<0.05). Observed T-cell priming could be driven by signaling networks of canonical T-cell stimulatory cytokines (IL-2, IL-12, and IL-15), which were upregulated at end-MDT and persisted at 3 mo F/U (all P<0.05). This modulation of T-cell phenotype, clonotype, and cytokine concentrations was not observed in the HT-monotherapy arm. At end-MDT, systemic T-cell responses were associated with improved PFS, most notably CD8+ T-cell expression of LAG-3 (aHR 0.22, 95% CI 0.03-0.91) and high TCR clonal expansion (aHR 0.13, 95% CI 0.02-0.52). High ctDNA burden at end-MDT correlated with worse PFS (aHR 1.41, 95% CI 1.04-2.54), as did CD8+ T-cell expression of inhibitory receptor TIGIT at 3 mo F/U (aHR 1.03, 95% CI 1.01-1.06).

CONCLUSION

The addition of MDT to HT induced systemic T-cell activation and expansion, which was not observed in the HT-only arm. This systemic immune response was independently associated with improved PFS. In addition to cytoreduction of macroscopic disease, MDT-induced immune education may be an important complementary mechanism of micrometastatic control in oligometastatic prostate cancer.

Addition of Metastasis-Directed Therapy to Standard of Care Systemic Therapy for Oligometastatic Breast Cancer (EXTEND): A Multicenter, Randomized Phase II Trial

PURPOSE/OBJECTIVE(S)

Prior retrospective and prospective evidence have suggested a potential survival benefit of adding metastasis-directed therapy (MDT) to standard of care systemic therapy for oligometastatic breast cancer. This has led to the increased utilization of MDT in this setting despite the lack of randomized evidence to support this approach. Furthermore, the recent presentation of NRG-BR002 has questioned the value of MDT. Thus, we evaluated whether the addition of MDT to systemic therapy improves PFS in oligometastatic breast cancer.

MATERIALS/METHODS

EXTEND (NCT03599765) is a phase II randomized basket trial for multiple solid tumors testing whether the addition of MDT improves PFS. The primary endpoint was pre-specified to be independently assessed and reported for the breast basket when a minimum of 6 months of follow-up had been reached. Patients with ≤5 metastases were randomized to standard of care systemic therapy with or without MDT. The choice of systemic therapy was at the discretion of the treating medical oncologist. Number of metastatic lesions and prior lines of systemic therapy for metastatic disease were used as stratification variables pre-randomization. The primary endpoint was progression-free survival (PFS) defined as time to randomization to date of clinical or radiographic progression or death. The study was designed to have 80% power to detect an improvement in median PFS from 18 to 36 months, with a type I error of 0.1.

RESULTS

Between September 2018 to July 2022, 43 patients were randomized. 22 patients were assigned to the MDT arm, and 21 patients to the no MDT arm. Three patients were not evaluable. The MDT arm patients were older vs the no-MDT arm patients (median 61.5 years vs 48 years, p = 0.01). Otherwise, the arms were well-balanced. Overall, 8 patients had triple negative disease (18.6%), and 12 patients (30%) had de novo metastatic disease. Of those patients with de novo presentation randomized to MDT, all except one had the primary tumor treated with surgery and radiation. At a median follow-up of 19.4 months, 20 events were observed. Among the 40 evaluable patients, there were 5 deaths (3 in the MDT arm and 2 in the no MDT arm). There was no difference in PFS between the MDT and no MDT arms (median 15.6 v 24.9 months, p = 0.66). Similarly, there was no difference in the secondary endpoint of time to new metastatic lesion appearance between the MDT and no MDT arms (median 15.6 months vs not reached, p = 0.09). Two grade 3 toxicities were observed in the MDT arm, and 1 in the no MDT arm. Further analysis of correlative translational biomarkers, including immune markers and ctDNA, are ongoing.

CONCLUSION

The addition of MDT to standard of care systemic therapy did not improve PFS or time to new metastatic lesion in patients with oligometastatic breast cancer. This data coupled with the recently presented NRG-BR002 results, suggests there is no benefit to MDT in an otherwise unselected oligometastatic breast cancer population.

Definitive local therapy for T4 prostate cancer associated with improved local control and survival

OBJECTIVES

To evaluate patients with clinical (c)T4 prostate cancer (PCa), which represent both a heterogenous and understudied population, who often present with locally advanced disease and obstructive symptoms causing significant morbidity and mortality. We analysed whether receiving definitive local therapy influenced symptomatic and oncological outcomes.

METHODS

Retrospective analysis of 154 patients with cT4 PCa treated at a single institution in 1996-2020. Systemic therapy with or without local treatment (surgery, radiotherapy [RT], or both). Uni- and multivariate analyses of associations between clinicopathological features (including obstructive symptoms) and receipt of local therapy on overall survival (OS) and disease control were done with Cox regression.

RESULTS

The median follow-up time was 5.9 years. Most patients had adenocarcinoma (88%), Gleason score 9-10 (77%), and median baseline prostate-specific antigen (PSA) of 20 ng/mL; most (54%) had metastatic cT4N0-1M1 disease; 24% regionally advanced cT4N1M0, and 22% localised cT4N0M0. Local therapies were RT (n = 44), surgery (n = 28), or both (n = nine). Local therapy was associated with improved OS (hazard ratio [HR] 0.3, P < 0.001), longer freedom from local recurrence (HR 0.39, P = 0.002), less local progression (HR 0.41, P = 0.02), fewer obstructive symptoms with progression (HR 0.31, P = 0.01), and less death from local disease (HR 0.25, P = 0.002). On multivariate, local therapy was associated with improved survival (HR 0.58, P = 0.02), and metastatic disease (HR 2.93, P < 0.001) or high-risk pathology (HR 2.05, P = 0.03) was associated with worse survival.

CONCLUSION

Definitive local therapy for cT4 PCa was associated with improved symptomatic outcomes and survival even among men with metastatic disease. Pending prospective evaluation, these findings support definitive treatment with local therapy for cT4 disease in select cases.

Addition of Metastasis-Directed Therapy to Intermittent Hormone Therapy for Oligometastatic Prostate Cancer: The EXTEND Phase 2 Randomized Clinical Trial

Importance

Despite evidence demonstrating an overall survival benefit with up-front hormone therapy in addition to established synergy between hormone therapy and radiation, the addition of metastasis-directed therapy (MDT) to hormone therapy for oligometastatic prostate cancer, to date, has not been evaluated in a randomized clinical trial.

Objective

To determine in men with oligometastatic prostate cancer whether the addition of MDT to intermittent hormone therapy improves oncologic outcomes and preserves time with eugonadal testosterone compared with intermittent hormone therapy alone.

Design, Setting, Participants

The External Beam Radiation to Eliminate Nominal Metastatic Disease (EXTEND) trial is a phase 2, basket randomized clinical trial for multiple solid tumors testing the addition of MDT to standard-of-care systemic therapy. Men aged 18 years or older with oligometastatic prostate cancer who had 5 or fewer metastases and were treated with hormone therapy for 2 or more months were enrolled to the prostate intermittent hormone therapy basket at multicenter tertiary cancer centers from September 2018 to November 2020. The cutoff date for the primary analysis was January 7, 2022.

Interventions

Patients were randomized 1:1 to MDT, consisting of definitive radiation therapy to all sites of disease and intermittent hormone therapy (combined therapy arm; n = 43) or to hormone therapy only (n = 44). A planned break in hormone therapy occurred 6 months after enrollment, after which hormone therapy was withheld until progression.

Main Outcomes and Measures

The primary end point was disease progression, defined as death or radiographic, clinical, or biochemical progression. A key predefined secondary end point was eugonadal progression-free survival (PFS), defined as the time from achieving a eugonadal testosterone level (≥150 ng/dL; to convert to nanomoles per liter, multiply by 0.0347) until progression. Exploratory measures included quality of life and systemic immune evaluation using flow cytometry and T-cell receptor sequencing.

Results

The study included 87 men (median age, 67 years [IQR, 63-72 years]). Median follow-up was 22.0 months (range, 11.6-39.2 months). Progression-free survival was improved in the combined therapy arm (median not reached) compared with the hormone therapy only arm (median, 15.8 months; 95% CI, 13.6-21.2 months) (hazard ratio, 0.25; 95% CI, 0.12-0.55; P < .001). Eugonadal PFS was also improved with MDT (median not reached) compared with the hormone therapy only (6.1 months; 95% CI, 3.7 months to not estimable) (hazard ratio, 0.32; 95% CI, 0.11-0.91; P = .03). Flow cytometry and T-cell receptor sequencing demonstrated increased markers of T-cell activation, proliferation, and clonal expansion limited to the combined therapy arm.

Conclusions and Relevance

In this randomized clinical trial, PFS and eugonadal PFS were significantly improved with combination treatment compared with hormone treatment only in men with oligometastatic prostate cancer. Combination of MDT with intermittent hormone therapy may allow for excellent disease control while facilitating prolonged eugonadal testosterone intervals.

Trial Registration

ClinicalTrials.gov Identifier: NCT03599765.

Treatment outcomes in patients (pts) with metastatic renal cell carcinoma (mRCC) with sarcomatoid and/or rhabdoid (S/R) features after progressive disease (PD) on immune checkpoint therapy (ICT): The MD Anderson Cancer Center experience

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Background: S/R mRCC is an aggressive disease that is associated with improved response to ICT. Studies performed prior to the approval of ICT demonstrated poor outcomes of S/R RCC with VEGF targeted therapies (TT). Here, we report outcomes of pts with S/R mRCC treated with VEGF TT after PD on ICT. Methods: We retrospectively reviewed the records of pts with mRCC with sarcomatoid (S), rhabdoid (R), or sarcomatoid plus rhabdoid (S+R) features who received VEGF TT after PD on ICT. Clinical endpoints of interest were time on VEGF TT and OS from treatment initiation. Directed acyclic graphs were used to identify confounders for adjustment in regression models. Hazard ratios (HR) and 95% confidence intervals (95% CI) were calculated using multivariable Cox regression. Multivariable models adjusted for epithelial histology, IMDC risk, prior VEGF TT, and inclusion of cabozantinib in the post-ICT VEGF TT regimen. Results: 57 pts with metastatic S/R RCC (52 with clear cell and 5 with non-clear cell histology) received a VEGF TT after PD on ICT. 46% of pts received a VEGF TT prior to ICT. After PD on ICT, 67% of pts had IMDC intermediate-risk disease; the most commonly used VEGF TT were cabozantinib (44%), either sunitinib, pazopanib, or axitinib (24%), and a VEGF TT in combination with an ICT (21%). Pts with R RCC had significantly longer time on VEGF TT compared with S RCC (adjusted HR = 0.45, 95% CI 0.21-0.94, p = 0.034), whereas the OS comparison was inconclusive (adjusted HR = 0.77, 95% CI 0.36-1.62, p = 0.486). IMDC risk classification following ICT progression was predictive of OS (adjusted HR = 2.22, 95% CI 1.07-4.61, p = 0.032), whereas, its association with time on VEGF TT was less conclusive (adjusted HR = 1.78, 95% CI 0.88-3.60, p = 0.107). Conclusions: Patients with S/R mRCC derive clinical benefit from VEGF TT after progression on ICT, and it is similar to the benefit previously described for patients without S/R features. Our findings suggest that the type of S/R features present and IMDC risk score inform the clinical benefit that VEGF TT will produce in this setting.[Table: see text]

Optimizing the diagnosis and management of ductal prostate cancer

Ductal adenocarcinoma (DAC) is the most common variant histological subtype of prostate carcinoma and has an aggressive clinical course. DAC is usually characterized and treated as high-risk prostatic acinar adenocarcinoma (PAC). However, DAC has a different biology to that of acinar disease, which often poses a challenge for both diagnosis and management. DAC can be difficult to identify using conventional diagnostic modalities such as serum PSA levels and multiparametric MRI, and the optimal management for localized DAC is unknown owing to the rarity of the disease. Following definitive therapy for localized disease with radical prostatectomy or radiotherapy, the majority of DACs recur with visceral metastases at low PSA levels. Various systemic therapies that have been shown to be effective in high-risk PAC have limited use in treating DAC. Although current understanding of the biology of DAC is limited, genomic analyses have provided insights into the pathology behind its aggressive behaviour and potential future therapeutic targets.

The efficacy of bevacizumab plus erlotinib (B+E) in patients (pts) with renal medullary carcinoma (RMC)

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Background: RMC is a rare and highly aggressive malignancy with a median overall survival (OS) of only 13 months from diagnosis. RMC is thought to be completely refractory to the targeted therapies used against clear cell renal cell carcinoma and the recommended standard of care therapy is platinum-based cytotoxic chemotherapy, which only produces a best response rate of 29% in the first line setting (Shah et al. BJU Int., 2017). Comprehensive molecular profiling of RMC tissues revealed a decrease in genes related to the tricarboxylic acid (TCA) cycle and oxidative phosphorylation and an increase in genes involved in fatty acid synthesis, demonstrating a reliance on aerobic glycolysis to meet cellular bioenergetics needs (Msaouel et al. Cancer Cell, 2020). The combination of B+E is particularly effective in tumors such as fumarate hydratate – deficient renal cell carcinomas, which also rely on aerobic glycolysis. We therefore hypothesized that B+E would show clinical efficacy against RMC. Methods: We analyzed 10 pts with RMC treated with B+E at our institution. A blinded board-certified radiologist reviewed all restaging images to assess best radiographic response as defined by RECIST v1.1 and, when applicable, date of progression. Adverse events (AEs) were evaluated using the CTCAE version 5.0 grading estimated from chart documentation. Clinical-grade next generation genome sequencing for gene mutations, copy number alterations and fusions was performed in 6/10 pts using the Oncomine platform. Results: Between 05/2005 and 09/2020, we identified 10 pts with RMC that were treated with B+E (Table). B+E produced a partial response in 2/10 pts (20%) and stable disease as best response in 6/10 pts (60%), resulting in a median progression-free survival of 3.5 months (mo) with 95% CI 1.8 – 5.2 mo. Decrease in tumor burden was noted even in patients that had received 3+ prior therapies and irrespective of genomic alterations. The median overall survival (OS) from B+E initiation was 7.3 mo (95% CI 5.4 – 9.1) and the median OS from diagnosis was 20.8 mo (95% CI 15.4 – 26.1). B+E was well tolerated with no grade ≥ 4 AEs and only one grade 3 AE (skin rash). Dose reduction was only needed in 1/10 pts. Conclusions: B+E is clinically active and well tolerated in heavily pre-treated pts with RMC and is therefore a viable therapeutic option for this lethal disease. However, pts ultimately relapse and further investigation is needed to elucidate mechanisms of resistance and determine how to optimally target metabolic vulnerabilities in RMC. [Table: see text]

Incidental Detection of Urothelial Carcinoma on 18F-Fluciclovine PET/CT

ABSTRACT

18F-Fluciclovine PET/CT has become a common diagnostic imaging study used in the evaluation of biochemical recurrence in prostate cancer since its approval in 2016. We present a case report of an 82-year-old man with history of both prostate and bladder cancer who presented for a fluciclovine study due to rising PSA levels. There was incidental detection of focal penile activity, and a subsequent urethral biopsy performed showed urothelial carcinoma, which was also seen on a subsequent MRI study.

Fully Balanced SSFP Without an Endorectal Coil for Postimplant QA of MRI-Assisted Radiosurgery (MARS) of Prostate Cancer: A Prospective Study

PURPOSE

To investigate fully balanced steady-state free precession (bSSFP) with optimized acquisition protocols for magnetic resonance imaging (MRI)-based postimplant quality assessment of low-dose-rate (LDR) prostate brachytherapy without an endorectal coil (ERC).

METHODS AND MATERIALS

Seventeen patients at a major academic cancer center who underwent MRI-assisted radiosurgery (MARS) LDR prostate cancer brachytherapy were imaged with moderate, high, or very high spatial resolution fully bSSFP MRIs without using an ERC. Between 1 and 3 signal averages (NEX) were acquired with acceleration factors (R) between 1 and 2, with the goal of keeping scan times between 4 and 6 minutes. Acquisitions with R >1 were reconstructed with parallel imaging and compressed sensing (PICS) algorithms. Radioactive seeds were identified by 3 medical dosimetrists. Additionally, some of the MRI techniques were implemented and tested at a community hospital; 3 patients underwent MARS LDR prostate brachytherapy and were imaged without an ERC.

RESULTS

Increasing the in-plane spatial resolution mitigated partial volume artifacts and improved overall seed and seed marker visualization at the expense of reduced signal-to-noise ratio (SNR). The reduced SNR as a result of imaging at higher spatial resolution and without an ERC was partially compensated for by the multi-NEX acquisitions enabled by PICS. Resultant image quality was superior to the current clinical standard. All 3 dosimetrists achieved near-perfect precision and recall for seed identification in the 17 patients. The 3 postimplant MRIs acquired at the community hospital were sufficient to identify 208 out of 211 seeds implanted without reference to computed tomography (CT).

CONCLUSIONS

Acquiring postimplant prostate brachytherapy MRI without an ERC has several advantages including better patient tolerance, lower costs, higher clinical throughput, and widespread access to precision LDR prostate brachytherapy. This prospective study confirms that the use of an ERC can be circumvented with fully bSSFP and advanced MRI scan techniques in a major academic cancer center and community hospital, potentially enabling postimplant assessment of MARS LDR prostate brachytherapy without CT.

Defining diagnostic criteria for ductal prostate cancer on prostatic MRI

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Background: Ductal prostate adenocarcinoma (DAC) is an aggressive histologic variant of prostate cancer (PCa) which often be missed due to their low PSA secretion. Further, a large proportion of DACs have extra-prostatic extension and nodal disease at presentation warranting accurate diagnosis and treatment planning. However studies have yet to differentiate DACs from high grade acinar PCas (PAC) on MRI. Therefore we aimed to develop MRI criteria to identify DACs and assess its diagnostic accuracy. Methods: Patients with histologically proven DAC who had MRIs prior to RP were identified from January 2011 to November 2018. Histology-based MRI diagnostic criteria were developed using RP specimens from nine patients with a pure dominant DAC focus and corresponding MRIs. Sixty-eight DAC patients were compared to a matched cohort of 70 patients with Gleason Score 8 or 9 PAC using the pre-defined MRI criteria. Chi-Squared, T tests, Mann Whitney U tests and sensitivity analyses were performed. Results: The following features of DAC were defined on MRI after correlation with histology: 1) intermediate T2 signal 2)well-circumscribed 3) lobulated tumor and 4) a dark peripheral rim. Majority of DACs were lobulated (79.4% vs 5.7%), with a dark peripheral rim on T2 weighted imaging (55.9% vs 4.3%) and had ≥3 MRI features compared to PAC (73.6% vs 7.2%) (all p < 0.001). Moreover, a higher proportion of pure DACs were lobulated (100% vs 5.7%), had a dark peripheral rim (94.7% vs 4.3%) and ≥3 MRI features (100% vs 7.2%) compared to PAC (all P < 0.001). There were no differences in median T2 contrast enhancement, ADC values or ADC ratios between the groups. Using our criteria MRI demonstrated sensitivity of 73.5%, specificity of 92.9 %, PPV of 90.9%, and NPV of 78.3% in diagnosing DACs if ≥3 features were present. In the diagnosis of pure DACs, MRI demonstrated sensitivity of 100%, specificity of 92.9%, PPV of 95.2%, and NPV of 100%. The area under the curve (AUC) for the diagnosis of all DACs was 0.81 and 0.98 for pure DACs. Conclusions: The presence of ≥3 features (well-circumscribed, lobulations and a dark peripheral rim and intermediate signal on the T2 phase) on prostatic MRI can help differentiate DAC from PAC. While this is the largest cohort of DACs to be analyzed, further studies are needed to validate these findings.

Outcomes of men with ductal prostate cancer undergoing definitive therapy for localized disease

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Background: Ductal prostate adenocarcinoma (DAC) is an aggressive variant of prostate cancer (PC). We aimed to assess the outcomes of men with localized DAC undergoing radical prostatectomy (RP) or external beam radiotherapy (RTx) compared to acinar adenocarcinoma of the prostate (PAC) and investigate any difference between these treatment modalities. Methods: All patients presenting to our institution with localized DAC from January 2005 - November 2018 were compared to a pooled cohort of patients from 3 tertiary referral centers who underwent RP for Gleason 8 PC and a cohort of high risk PC patients who underwent RTx for PAC. Patient, tumor characteristics and outcome data were analyzed. Results: 257 men with DAC were identified and compared to 803 with PAC. 203 men with DAC and 729 men with PAC underwent RP while 54 men with DAC and 74 men with PAC underwent RTx. Men with DAC were older (65 vs 63 years and 70.5 vs 66 years) and had higher cT3/T4 stage (43% vs 2.8% and 44.5% vs 31.1%) in both groups, respectively (all p <0.05). The median follow-up for men undergoing RP was 34 (range 0.9 to 177) months and 73.4 (range 0.6 – 224.2) months for men having RTx. Presence of DAC was an independent risk factor for metastases (HR 2.5 (95% CI 1.4- 4.8); p<0.01) and death (HR 2.3 (95% CI 1.1 – 4.7); p=0.02) following RP. The 3- year overall survival (OS) rates for DAC and PAC in men undergoing RP were 93.3% vs 99.3% (p<0.01). On adjusting for Gleason score, clinical T stage, PSA and age, DAC was also an independent risk factor for death (HR 6.1 (95% CI 1.7-22.2); p<0.01) in men undergoing RTx with 5-year OS rates of 100% and 81.6% for DAC and PAC, respectively. There was no difference in the OS of men with DAC between RP and RTx. Conclusions: Men undergoing RP or RTx for localized DAC had worse outcomes compared to PAC, but no survival difference was seen between these treatment modalities. DAC behaves clinically differently than PAC. Further evaluation of the underlying biology and potential for specific targeted multimodality therapies in DAC is needed.

Nivolumab for the Treatment of Patients with Metastatic Non-Clear Cell Renal Cell Carcinoma (nccRCC): A Single-Institutional Experience and Literature Meta-Analysis

INTRODUCTION

Nivolumab alone and in combination with ipilimumab is approved for the treatment of patients with metastatic renal cell carcinoma (RCC) who received prior vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKI) and those who are treatment naive, respectively. However, the clinical activity of nivolumab in non-clear cell RCC (nccRCC) is unknown, as these patients were excluded from the trials.

MATERIALS AND METHODS

We reviewed the records of patients who received nivolumab for nccRCC and ccRCC with >20% rhabdoid with the primary endpoint to assess the objective response rate (ORR). We assessed radiographic response using RECIST, v1.1. Secondary endpoints were progression-free survival (PFS) and overall survival (OS). We also reviewed the literature to identify studies reporting on the clinical activity of immune checkpoint inhibitors in nccRCC, and performed a meta-analysis of proportions for ORR and disease control rate (DCR).

RESULTS

Twelve patients (30%) had papillary histology, 11 (27.5%) had unclassified, 8 (20%) had ccRCC with rhabdoid component, 5 (12.5%) had chromophobe, 3 (7.5%) had translocation, and 1 (2.5%) had mucinous tubular and spindle cell carcinoma. Overall, seven patients (21.6%, 95% confidence interval [CI], 8.7%-37.9%) had an objective response, including three patients (8.8%, 95% confidence interval [CI], 1.9%-23.7%) who achieved a complete remission. At a median follow-up of 24.5 monoths (95% CI, 17.7-32.6), median PFS was 4.9 monoths (95% CI, 3.53-10.27) and median OS was 21.7 monoths (95% CI, 7.83 mo to not reached). There were no treatment-related deaths. We also identified two retrospective studies reporting best ORR in patients with nccRCC receiving PD-1/PD-L1 checkpoint blockade. The ORR and DCR for the total cohort were, respectively, 18.6% (95% CI, 11.9%-26.4%) and 53.4% (95% CI, 44.2%-62.5%).

CONCLUSION

Nivolumab demonstrated activity in unclassified nccRCC and ccRCC with >20% rhabdoid; further randomized clinical trials are warranted.

IMPLICATIONS FOR PRACTICE

This article reports on the clinical activity and safety of immune checkpoint inhibitors in non-clear cell kidney cancer. The retrospective data with the meta-analysis provides a summary that will help guide the treatment of this rare and heterogeneous group of kidney cancers.

Management of cT4 Prostate Cancer

While radiotherapy with androgen deprivation therapy is the current standard of care for the treatment of stage cT4 prostate cancer (PC), surgery may also be an appropriate option in selected patients as part of a multimodal approach. The role and the sequence with which to optimize therapy combinations in this setting are still unknown. This mini review summarizes the current evidence for management of cT4 PC. PATIENT SUMMARY: This mini review examines current evidence for the treatment options for locally advanced prostate cancer. The role of surgery in these patients can be considered as part of a combination treatment strategy along with other modalities such as radiotherapy and hormone therapy.

Comprehensive radiogenomics analysis of qualitative and quantitative features of cross-sectional imaging in the TCGA project in MIBC

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Background: Quantitative imaging descriptors derived from CT and MRI can be integrated with genomic data that may be used as non-invasive prognostic or predictive biomarkers. We report an integrated radiogenomics project designed to develop subjective and objective parameters extracted from cross-sectional imaging of MIBC from studies archived in the TCIA and linked to the TCGA project. Methods: We reported comprehensive integrated genomic analysis of 412 tumors (Cell 2017). 7 of 33 tissue source sites submitted CT scans to the TCIA (n=106). We developed 17 features describing tumor size/location, metastases sites, and tumor morphology; 9 GU radiologists reviewed the scans in a blinded manner. EH analyzed the data independent of the radiologists. We computed kappa statistics for categorical features and coverage probabilities for quantitative features (Lin et al 2002). The tumor was segmented on an axial image and the segmented image analyzed using a radiomics panel (radiomicslab.usc.edu). Associations between individual features and subtypes were assessed (Fisher’s Exact Test) for categorical features and Kruskal-Wallis Test for quantitative features. Results: Substantial agreement (k≥ 0.6) was observed in 4 features: tumor laterality, tumor within bladder diverticulum, right and left UVJ involvement and hydroureter. We observed weak agreement (95% CI <0.4) for bladder neck, posterior bladder, dome, and trigone involvement, tumor margin, internal architecture, radiographic stage, left upper tract involvement, and metastases. The coverage probability for lesion size was 0.59 (0.544-0.638) (Figure). Tumor morphology was associated with microRNA cluster, with diffuse wall thickening having a higher tendency toward Clusters 3 and 4 (p < .001). Radiomic analysis identified statistically significant associations of mutations in FGFR3, CREBBP, CASP8 and EP300 with multiple radiomic features. Conclusions: This blinded comprehensive assessment of features extracted from CT images highlights many of the ongoing challenges in staging patients with MIBC. Preliminary analysis shows promise in analyzing associations between radiomic features and mutations.

Is expanded radiographic criteria for clinically positive lymph nodes associated with outcome in pathologically node positive prostate cancer?

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Background: Patients with pN1 prostate cancer (PCa) have heterogeneous outcomes largely dependent on variables only known post-treatment. Traditionally, the size criteria for clinically positive pelvic adenopathy is axial diameter of 10mm. We employed expanded radiographic criteria (ERC) to evaluate for association with differences in outcome differences. Methods: 187 men treated with RP BPLND for PCa from 2001-2013 were identified as pN1. Imaging studies were re-reviewed by a single radiologist (TB) for nodes that were considered positive if they were 8mm or greater in size OR if they were 6mm or greater in size AND either rounded, asymmetrical OR heterogeneously enhancing. This yielded a group of 34 cN1 patients by ERC. Time to biochemical recurrence (BCR) was compared between cN0 and cN1 patients by K-M method. Cox proportional hazards modeling was used to determine association of baseline PSA, node status, adjuvant therapy, Gleason score, positive margins, and ECR with time to BCR and overall survival (OS). Results: Median age (61 v 59 p = 0.3), baseline PSA (8.7 v 11.1 p = 0.2), and positive margin rate (33% vs 32% p = 0.9) did not differ between cN0 and cN1 patients. Median number of positive LNs was higher in the cN1 group (2.7 v 1.8) p = 0.03. Median biochemical recurrence free survival did not differ between groups (3.3 vs 1.8 years p = 0.3) (Fig1). Only Gleason score was associated with shorter BCR free survival HR 1.3 (95%CI 1.0-1.62, p = 0.047). cN1 disease with expanded radiographic criteria did not predict BCR (HR 1.03, 95CI 0.62-171, p = 0.9) or ACM (HR 0.46, 95CI, 0.1-2.12, p = 0.3). Conclusions: Expanded radiographic criteria for clinically positive lymph nodes was not associated with BCR-free survival or OS in a group of pN1 PCa patients. Further study is required to determine if cN1 status based on expanded clinical criteria or more sensitive imaging methods is associated with outcome differences.

Permanent prostate brachytherapy postimplant magnetic resonance imaging dosimetry using positive contrast magnetic resonance imaging markers

PURPOSE

Permanent prostate brachytherapy dosimetry using computed tomography-magnetic resonance imaging (CT-MRI) fusion combines the anatomic detail of MRI with seed localization on CT but requires multimodality imaging acquisition and fusion. The purpose of this study was to compare the utility of MRI only postimplant dosimetry to standard CT-MRI fusion-based dosimetry.

METHODS AND MATERIALS

Twenty-three patients undergoing permanent prostate brachytherapy with use of positive contrast MRI markers were included in this study. Dose calculation to the whole prostate, apex, mid-gland, and base was performed via standard CT-MRI fusion and MRI only dosimetry with prostate delineated on the same T2 MRI sequence. The 3-dimensional (3D) distances between seed positions of these two methods were also evaluated. Wilcoxon-matched-pair signed-rank test compared the D90 and V100 of the prostate and its sectors between methods.

RESULTS

The day 0 D90 and V100 for the prostate were 98% versus 94% and 88% versus 86% for CT-MRI fusion and MRI only dosimetry. There were no differences in the D90 or V100 of the whole prostate, mid-gland, or base between dosimetric methods (p > 0.19), but prostate apex D90 was high by 13% with MRI dosimetry (p = 0.034). The average distance between seeds on CT-MRI fusion and MRI alone was 5.5 mm. After additional automated rigid registration of 3D seed positions, the average distance between seeds was 0.3 mm, and the previously observed differences in apex dose between methods was eliminated (p > 0.11).

CONCLUSIONS

Permanent prostate brachytherapy dosimetry based only on MRI using positive contrast MRI markers is feasible, accurate, and reduces the uncertainties arising from CT-MRI fusion abating the need for postimplant multimodality imaging.

Permanent prostate brachytherapy pubic arch evaluation with diagnostic magnetic resonance imaging

PURPOSE

Pubic arch interference (PAI), when it occurs, is often a limiting factor for patients pursuing brachytherapy treatment of prostate cancer. Pre-brachytherapy pubic arch evaluation is often performed by CT or transrectal ultrasound (TRUS), but MRI has increasingly replaced these modalities for prostate cancer evaluation. The purpose of this study was to determine if staging MRI could be used to evaluate PAI and compare it with these other imaging methods.

METHODS AND MATERIALS

Forty-one consecutive patients undergoing brachytherapy evaluation had pelvic MRI-, CT-, and TRUS-based brachytherapy simulation. Pubic arch overlap on T2-weighted MRI and CT was determined by contouring the prostate gland on its largest axial slice and superimposing this contour onto the pubic arch bones. The largest degree of overlap of the prostate gland on MRI and CT was used to predict the existence of PAI as determined by TRUS-based simulation. The correlation between prostate contour overlap was also compared between MRI and CT.

RESULTS

Nineteen patients (48%) exhibited PAI on TRUS brachytherapy simulation evaluation. The average (±standard error) amount of prostate contour overlap on the pubic arch on CT was 2.9 ± 0.6 mm and on MRI was 2.0 ± 0.6 mm (linear correlation, R, of 0.783, p < 0.001). CT and MRI were equally predictive of PAI on TRUS evaluation (area under the curve = 0.75).

CONCLUSION

Pre-brachytherapy pubic arch assessment with diagnostic MRI provides similar predictability of PAI compared with CT, potentially obviating the need for additional pre-brachytherapy CT in the setting of staging MRI.

Outcomes of unselected patients with metastatic clear-cell renal cell carcinoma treated with first-line pazopanib therapy followed by vascular endothelial growth factor receptor tyrosine kinase inhibitors or mammalian target of rapamycin inhibitors: a single institution experience

OBJECTIVE

To explore the efficacy and safety of pazopanib in a 'real-world' setting in unselected patients, as data regarding unselected patients with metastatic clear-cell renal cell carcinoma (ccRCC) treated with first-line pazopanib are limited.

PATIENTS AND METHODS

We reviewed records of patients with metastatic ccRCC treated with first-line pazopanib from 1 November 2009 through to 1 November 2012. Cox models were fitted to evaluate the association of progression-free survival (PFS) and overall survival (OS) with patient co-variables.

RESULTS

In all, 88 patients were identified; 74 were evaluable for response: two (3%) had a complete response, 27 (36%) a partial response, 36 (49%) had stable disease and nine (12%) had progressive disease. The median PFS was 13.7 months [95% confidence interval (CI) 8.7-18.3]. PFS was correlated with a Karnofsky Performance Status score of <80 [hazard ratio (HR) 3.26, P < 0.001] and serum lactate dehydrogenase of >1.5 × upper limit of normal (HR 3.25, P = 0.014). The median OS was 29.1 months (95% CI 20.2-not reached). The OS was correlated with brain metastasis (HR 2.55, P = 0.009), neutrophilia (HR 1.179, P = 0.018), and anaemia (HR 3.51, P < 0.001). There were no treatment-related deaths. In all, 53 patients received second-line therapy [vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKI) in 22 patients, mammalian target of rapamycin inhibitors (mTORi) in 22 patients, and other therapy in nine patients]; the median PFS was 8.6 months (95% CI 3.3-25.7) with VEGFR-TKI and 5 months (95% CI 3.5-15.2) with mTORi (P = 0.41); the median OS was 19.9 months (95% CI 12.9-not reached) and 14.2 months (95% CI 8.1-not reached), from initiation of second-line VEGFR-TKI or mTORi, respectively (P = 0.37).

CONCLUSIONS

In this retrospective study, first-line pazopanib confirmed its efficacy in metastatic ccRCC. Trends for longer PFS and OS were seen with VEGFR-TKI compared with mTORi after first-line pazopanib.

Clinical outcomes for patients with metastatic renal cell carcinoma treated with alternative sunitinib schedules

PURPOSE

We identified sunitinib alternative schedules that maintained dose intensity while decreasing adverse events in patients with metastatic renal cell cancer. We also determined the impact of alternative schedules on clinical outcomes.

MATERIALS AND METHODS

We retrospectively reviewed the records of patients 18 years old or older with clear cell metastatic renal cell cancer who received first line sunitinib between January 26, 2006 and March 1, 2011 at our major comprehensive cancer center. A subset of patients was switched at the first intolerable adverse event from the traditional schedule of 28 days on and 14 days off to a schedule of 14 days on and 7 days off or other alternative schedules. A control group underwent standard dose reduction. We estimated progression-free and overall survival by the Kaplan-Meier method. Predictors of progression-free and overall survival were analyzed using Cox regression.

RESULTS

A total of 187 patients were included in analysis, of whom 87% were on the traditional schedule at baseline. During treatment 53% of patients continued on the traditional schedule and 47% began or were transitioned to alternative schedules. Baseline characteristics were similar. Adverse events prompting schedule modification included fatigue in 64% of cases, hand-foot syndrome in 38% and diarrhea in 32%. Median time to alternative schedules was 5.6 months. Median overall survival was 17.7 months (95% CI 10.8-22.2) on the traditional schedule compared to 33.0 months (95% CI 29.3-not estimable) on alternative schedules (p <0.0001). On multivariable analysis poor Eastern Cooperative Oncology Group (ECOG) performance status, increased lactate dehydrogenase, decreased albumin, unfavorable Heng criteria and the traditional schedule were associated with decreased overall survival (p <0.05).

CONCLUSIONS

Sunitinib administered on alternative schedules may mitigate adverse events while achieving outcomes comparable to those of the traditional schedule in patients with metastatic renal cell cancer. Prospective investigations of alternate dosing schemas are warranted.

Outcomes associated with sunitinib alternative schedule compared to traditional schedule: a single-center experience

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Background: Sunitinib is a front-line therapy for metastatic renal cell cancer (mRCC). Recommended dose is 50 mg daily; 28 days (d) on/14 d off (traditional schedule; TS). Sunitinib is associated with several adverse events (AEs). An ideal treatment modification algorithm is not known. We sought to identify 1) common AEs, 2) alternative schedules (AS) that maintained dose intensity while decreasing AEs, and 3) the impact of AS on outcomes. Methods: Single-center retrospective review of mRCC pts performed from 1/26/06 to 3/1/11. Pts > 18 years of age with mRCC who received first-line antiangiogenic therapy with sunitinib were eligible. A subset of pts were switched at first intolerable AE from TS to a 14 d/7 d, or further adjusted to 7 d /3 d, or other AS. Control group underwent standard dose reduction. Pt characteristics including demographics, disease status, laboratory data, AEs, AS, and treatment outcomes were analyzed. Results: 186 eligible pts were identified. At baseline, 87% received sunitinib 50 mg and 88% were on TS. 99 pts (53%) continued TS and 87 pts (47%) were switched to AS. Baseline characteristics were similar. Median age was 61 yrs; by MSKCC criteria 5% were good, 50% intermediate, and 45% poor prognosis. Pts had median 2 visceral mets and 42% had primary tumor in place. AEs included fatigue (47%), diarrhea (24%), and hand-foot syndrome (26%). Median time to AS was 126 d with 14 d/7 d the most common (82%). Median time on treatment was 14.9 months (mo) (95% CI:10.2 – 17.0 mo) in AS pts vs 4.2 mo (95% CI: 3.6 – 5.7 mo), respectively (p < 0.0001). Median OS was 32.9 mo (95% CI:28.3-54.1 mo) vs 18.5 mo (95% CI: 10.3-21.5 mo), respectively (p = 0.0001). ECOG PS > 2 (HR 3.9), elevated LDH (HR 2.04), and > 2 mets (HR 1.79) were associated with decreased OS. MSKCC intermediate vs poor (HR 0.57) and AS (HR 0.54) were associated with improved OS by multivariate regression analysis (p < 0.05). Conclusions: In our cohort study, AS sunitinib significantly prolonged time on treatment and was predictive of OS. Prospective investigations of alternate dosing schemas are warranted.