Tumor Genomic Testing for >4000 Men with Metastatic Castration-resistant Prostate Cancer in the Phase III Trial PROfound (Olaparib)

PURPOSE

Successful implementation of genomic testing in clinical practice is critical for identification of men with metastatic castration-resistant prostate cancer (mCRPC) eligible for olaparib and future molecularly targeted therapies.

PATIENTS AND METHODS

An investigational clinical trial assay, based on the FoundationOne^®CDx tissue test, was used to prospectively identify patients with qualifying homologous recombination repair (HRR) gene alterations in the phase III PROfound study. Evaluation of next-generation sequencing (NGS) tissue test outcome against pre-analytical parameters was performed to identify key factors influencing NGS result generation.

RESULTS

4858 tissue samples from 4047 patients were tested and reported centrally. NGS results were obtained in 58% (2792/4858) of samples, equating to 69% of patients. Of samples submitted, 83% were primary tumor samples (96% were archival and 4% newly obtained). Almost 17% were metastatic tumor samples (60% were archival and 33% newly obtained). NGS results were generated more frequently from newly obtained compared with archival samples (63.9% v. 56.9%), and metastatic compared with primary samples (63.9% v. 56.2%). Although generation of an NGS result declined with increasing sample age, approximately 50% of samples aged >10 years generated results. While higher tumor content and DNA yield resulted in greater success in obtaining NGS results, other factors, including selection and preservation of samples, may also have had an impact.

CONCLUSIONS

The PROfound study demonstrates that tissue testing to identify HRR alterations is feasible and that high-quality tumor tissue samples are key to obtaining NGS results and identifying patients with mCRPC who may benefit from olaparib treatment.

Primary results of STRONG: An open-label, multicenter, phase 3b study of fixed-dose durvalumab monotherapy in previously treated patients with urinary tract carcinoma

BACKGROUND

Prior durvalumab (anti-PD-L1 agent) studies in platinum-refractory metastatic urothelial carcinoma evaluated a dose of 10 mg/kg administered every two weeks. The nonrandomised phase 3b STRONG study (NCT03084471) evaluated the safety and efficacy of fixed-dose durvalumab at a more convenient dosing schedule in a previously treated patient population, more similar to a real-world clinical setting.

PATIENTS AND METHODS

867 patients with urothelial or nonurothelial urinary tract carcinoma (UTC) who progressed on or after platinum or nonplatinum chemotherapy were treated with durvalumab 1500 mg every four weeks; 87% had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1, and 13% had an ECOG PS of 2. The primary end-point was the incidence of adverse events of special interest (AESIs), including immune-mediated AEs (imAEs). Secondary and exploratory end-points included overall survival (OS), objective response rate (ORR) and disease control rate (at six and 12 months) (DCR).

RESULTS

AESIs of any grade were reported in 51% of patients (8% grade ≥ 3). The incidence of imAEs was 11% (2% grade ≥ 3). The median OS was 7.0 months (95% confidence interval [CI]: 6.4-8.2) and ORR was 18% (95% CI: 14.8-20.6), with complete responses in 5% of patients and a DCR at six months of 19% (95% CI: 16.1-22.1).

CONCLUSION

Fixed-dose durvalumab monotherapy every four weeks has an acceptable safety profile and yields durable clinical activity in previously chemotherapy-treated patients with UTC. Safety and efficacy are consistent with previous durvalumab studies and other anti-PD-1/PD-L1 agents in this setting. CLINICALTRIALS.

GOV IDENTIFIER

NCT03084471https://clinicaltrials.gov/ct2/show/NCT03084471.

Same-day-discharge Robot-assisted Radical Prostatectomy: An Annual Countrywide Analysis

There are no countrywide data regarding the utilization of same-day-discharge (SDD) surgery for robot-assisted radical prostatectomy (RARP). We aimed to evaluate the annual number of SDD RARP procedures in France and to compare postoperative outcomes in SDD versus non-SDD centers. Data for all 9651 patients undergoing RARP in France in 2020 were extracted from the central database of the national healthcare system. Endpoints were length of hospital stay, patient age, center volume, lymph node dissection, and the hospital readmission rate. Overall, 184 SDD cases (1.9%) were reported in 14.2% of RARP centers. The annual RARP and SDD RARP caseload ranged from 41 to 485, and from one to 47, respectively, in SDD centers. SDD was significantly associated with higher-volume centers (p < 0.001). No difference in readmission rate (7.9% vs 5.1%; p = 0.141) was observed for SDD versus non-SDD centers. Direct stay costs were estimated at €1457 in SDD centers compared to €2021 in non-SDD centers. The main limitation is the lack of detailed patient characteristics and readmission causes. This annual nationwide analysis suggests that SDD RARP remains infrequently used in routine practice in France despite being associated with comparable short-term outcomes after RARP and potential cost benefits.

Patient summary

We evaluated the use of robot-assisted removal of the prostate (RARP) with same-day hospital discharge in France for men with prostate cancer. In 2020, only 1.9% of the 9651 RARP procedures involved same-day discharge, even though the data show that this approach has lower costs and comparable safety.

Overview of the Development and Use of Akt Inhibitors in Prostate Cancer

Deregulation of the PI3K-Akt-mTOR pathway plays a critical role in the development and progression of many cancers. In prostate cancer, evidence suggests that it is mainly driven by PTEN loss of function. For many years, the development of selective Akt inhibitors has been challenging. In recent phase II and III clinical trials, Ipatasertib and Capivasertib associated with androgen deprivation therapies showed promising outcomes in patients with metastatic castration-resistant prostate cancer and PTEN-loss. Ongoing trials are currently assessing several Akt inhibitors in prostate cancer with different combinations, at different stages of the disease.

Oncologic Impact and Safety of Pre-Operative Radiotherapy in Localized Prostate and Bladder Cancer: A Comprehensive Review from the Cancerology Committee of the Association Française d'Urologie

Simple Summary

Radiotherapy may have an interesting role of reinforcing the loco-regional control of cancer, in addition to surgery, when used as a preoperative treatment. This sequence has demonstrated its efficacy and safety in various malignancies, but no strong data exist in the era of uro-oncology. In this review article, we aim to highlight the potential usefulness of preoperative radiotherapy in prostate and muscle-invasive bladder cancer, aiming to enhance pathological response and local control and to prevent intraoperative tumor seeding. We also emphasize the need for further clinical studies assessing the functional safety of subsequent surgical procedures in a competitive context of new systemic agents that have proven to demonstrate a survival benefit in locally advanced urologic cancers.

Abstract

Preoperative radiotherapy (RT) is commonly used for the treatment of various malignancies, including sarcomas, rectal, and gynaecological cancers, but it is preferentially used as a competitive treatment to radical surgery in uro-oncology or as a salvage procedure in cases of local recurrence. Nevertheless, preoperative RT represents an attractive strategy to prevent from intraoperative tumor seeding in the operative field, to sterilize microscopic extension outside the organ, and to enhance the pathological and/or imaging tumor response rate. Several clinical works support this research field in uro-oncology. In this review article, we summarized the oncologic impact and safety of preoperative RT in localized prostate and muscle-invasive bladder cancer. Preliminary studies suggest that both modalities can be complementary as initial primary tumor treatments and that a pre-operative radiotherapy strategy could be beneficial in a well-defined population of patients who are at a very high-risk of local relapse. Future prospective trials are warranted to evaluate the oncologic benefit of such a combination of local treatments in addition to new life-prolonging systemic therapies, such as immunotherapy, and new generation hormone therapies. Moreover, the safety and the feasibility of salvage surgical procedures due to non-response or local recurrence after pelvic RT remain poorly evaluated in that context.

Annual nationwide analysis of costs and post-operative outcomes after radical prostatectomy according to the surgical approach (open, laparoscopic, and robotic)

OBJECTIVE

Annual countrywide data are scarce when comparing surgical approaches in terms of hospital stay outcomes and costs for radical prostatectomy (RP). We aimed to assess the impact of surgical approach on post-operative outcomes and costs after RP by comparing open (ORP), laparoscopic (LRP), and robot-assisted (RARP) RP in the French healthcare system.

PATIENTS AND METHODS

Data from all patients undergoing RP in France in 2020 were extracted from the central database of the national healthcare system. Primary endpoints were length of hospital stay (LOS including intensive care unit (ICU) stay if present), complications (estimated by severity index), hospital readmission rates (at 30 and 90 days), and direct costs of initial stay.

RESULTS AND LIMITATIONS

A total of 19,018 RPs were performed consisting in ORP in 21.1%, LRP in 27.6%, and RARP in 51.3% of cases. RARP was associated with higher center volume (p < 0.001), lower complication rates (p < 0.001), shorter LOS (p < 0.001), and lower readmission rates (p = 0.004). RARP was associated with reduced direct stay costs (2286 euros) compared with ORP (4298 euros) and LRP (3101 euros). The main cost driver was length of stay. The main limitations were the lack of mid-term data, readmission details, and cost variations due to surgery system.

CONCLUSIONS

This nationwide analysis demonstrates the benefits of RARP in terms of post-operative short-term outcomes. Higher costs related to the robotic system appear to be balanced by patient care improvements and reduced direct costs due to shorter LOS.

A 5-Year Contemporary Nationwide Evolution of the Radical Prostatectomy Landscape

The evolution in the past decade of recommendations for prostate cancer (PCa) management, from screening to surgical treatment, may have affected the radical prostatectomy (RP) landscape. However, comprehensive data at a national level remain scarce. We extracted 5-yr data for RP patients in France from the central database of the national health care system. The primary endpoints were surgical approach (open [ORP], laparoscopic [LRP], and robot-assisted RP [RARP]), length of stay (LOS), and complication and readmission rates. The annual number of RPs was stable during the study period. The proportion of RARPs increased from 39.8% in 2015 to 52.6% in 2019, whereas the proportion of ORPs decreased from 34.4% to 24.5%. LOS continuously decreased over time irrespective of the surgical approach. The proportion of centres in the highest quartile of hospital volume increased from 22.0% to 28.3% (p = 0.006). LOS and complication and readmission rates were significantly lower (p < 0.001) in the LRP cohort at each time point. National trends confirmed that RARP progressively replaced ORP, with a stable number of annual RPs over time. Greater centralisation and better early postoperative outcomes were observed with laparoscopy.

Patient summary

We reviewed French data for patients undergoing removal of the prostate for prostate cancer between 2015 and 2019. We found that robot-assisted minimally invasive surgery has increased over time and the length of hospital stays has decreased. Rates of complications and readmission were lower with minimally invasive surgery.

Cabazitaxel activity in men with metastatic castration-resistant prostate cancer with and without DNA damage repair defects

BACKGROUND

Cabazitaxel was shown to improve overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC) after abiraterone/enzalutamine and docetaxel failure, though benefit by the presence of DNA damage repair (DDR) defects is unknown. With the advent of poly(adenosine diphosphate-ribose) polymerase inhibitors (PARPi) in partially overlapping indications with cabazitaxel, we aimed to determine cabazitaxel activity in men with mCRPC according to their DDR status.

METHODS

This is a retrospective multicenter study that enrolled patients with mCRPC treated with cabazitaxel who had undergone DDR tumour tissue profiling. Patients with at least one deleterious germline or somatic alterations were considered DDR positive (DDR+). Each DDR + patient has been matched with a DDR negative (DDR-) from the same institution who underwent the same test. An exploratory cohort of patients found to be DDR + by liquid biopsy was also included. Prostate specific antigen (PSA) decline≥50% (PSA50), PSA progression-free survival (PFS, PSA-PFS), radiographic PFS (rPFS), clinical PFS or radiographic PFS (c/rPFS) and OS were evaluated.

RESULTS

Among 190 men (95 DDR+, 95 DDR-) with tissue sequencing, PSA50 was achieved with cabazitaxel in 29/92 (32%) and 33/92 (36%) in patients with DDR+ and DDR- (P = 0.64). The median rPFS was 5.33 months [95%CI 4.34-7.04] versus 5.75 months [95%CI 4.67-7.27] (P = 0.55). The median OS was 15.4 months [95%CI 12.16-26.6] and 11.5 months [95%CI 9.76-14.4] (P = 0.036), respectively. No PSA50 responses on cabazitaxel were observed in BRCA1/2 patients previously treated with PARPi (n = 10). Similar outcomes with cabazitaxel were observed in the liquid biopsy cohort (n = 63 DDR+).

CONCLUSIONS

Our study suggests that cabazitaxel is active in patients with mCRPC regardless of their DDR status, although its activity in men pretreated with a PARPi may be lower.

Biomarker in Active Surveillance for Prostate Cancer: A Systematic Review

Active surveillance (AS) in prostate cancer (PCa) represents a curative alternative for men with localised low-risk PCa. Continuous improvement of AS patient's selection and surveillance modalities aims at reducing misclassification, simplifying modalities of surveillance and decreasing need for invasive procedures such repeated biopsies. Biomarkers represent interesting tools to evaluate PCa diagnosis and prognosis, of which many are readily available or under evaluation. The aim of this review is to investigate the biomarker performance for AS selection and patient outcome prediction. Blood, urinary and tissue biomarkers were studied and a brief description of use was proposed along with a summary of major findings. Biomarkers represent promising tools which could be part of a more tailored risk AS strategy aiming to offer personalized medicine and to individualize the treatment and monitoring of each patient. The usefulness of biomarkers has mainly been suggested for AS selection, whereas few studies have investigated their role during the monitoring phase. Randomized prospective studies dealing with imaging are needed as well as larger prospective studies with long-term follow-up and strong oncologic endpoints.

Mature tertiary lymphoid structures predict immune checkpoint inhibitor efficacy in solid tumors independently of PD-L1 expression

Only a minority of patients derive long-term clinical benefit from anti-PD1/PD-L1 monoclonal antibodies. The presence of tertiary lymphoid structures (TLS) has been associated with improved survival in several tumor types. Here, using a large-scale retrospective analysis of three independent cohorts of cancer patients treated with anti-PD1/PD-L1 antibodies, we showed that the presence of mature TLS was associated with improved objective response rate, progression-free survival, and overall survival independently of PD-L1 expression status and CD8+ T-cell density. These results pave the way for using TLS detection to select patients who are more likely to benefit from immune checkpoint blockade.

Single-Center Experience of Focal Thermo-Ablative Therapy After Pelvic Radiotherapy for In-Field Prostate Cancer Oligo-Recurrence

PURPOSE

In-field prostate cancer (PCa) oligo-recurrence after pelvic radiotherapy is a challenging situation for which metastasis-directed treatments may be beneficial, but options for focal therapies are scarce.

METHODS

We retrospectively reviewed data for patients with three or less in-field oligo-recurrent nodal, bone and/or locally recurrent (prostate, seminal vesicles, or prostatic bed) PCa lesions after radiation therapy, identified with molecular imaging (PET and/or MRI) and treated by focal ablative therapy (cryotherapy or radiofrequency) at the Institut Bergonié between 2012 and 2020. Chosen endpoints were the post-procedure PSA response (partially defined as a >50% reduction, complete as a PSA <0.05 ng/ml), progression-free survival (PFS) defined as either a biochemical relapse (defined as a rise >25% of the Nadir and above 2 ng/ml), radiological relapse (on any imaging technique), decision of treatment modification (hormonotherapy initiation or line change) or death, and tolerance.

RESULTS

Forty-three patients were included. Diagnostic imaging was mostly 18F-Choline positron emission tomography/computerized tomography (PET/CT) (75.0%), prostate specific membrane antigen (PSMA) PET/CT (9.1%) or a combination of pelvic magnetic resonance imaging (MRI), CT, and 99 mTc-bone scintigraphy (11.4%). PSA response was observed in 41.9% patients (partial in 30.3%, complete in 11.6%). In the hormone-sensitive exclusive focal ablation group (n = 31), partial and complete PSA responses were 32.3 and 12.9% respectively. Early local control (absence of visible residual active target) on the post-procedure imaging was achieved with 87.5% success. After a median follow-up of 30 months (IQR 13.3-56.8), the median PFS was 9 months overall (95% CI, 6-17), and 17 months (95% CI, 11-NA) for PSA responders. Complications occurred in 11.4% patients, with only one grade IIIb Dindo-Clavien event (uretral stenosis requiring endoscopic uretrotomy).

CONCLUSION

In PCa patients showing in-field oligo-recurrence after pelvic radiotherapy, focal ablative treatment is a feasible option, possibly delaying a systemic treatment initiation or modification. These invasive strategies should preferably be performed in expert centers and discussed along other available focal strategies in multi-disciplinary meetings.

Nephrectomy after response to immune checkpoint inhibitors for metastatic renal cell carcinoma (mRCC): A surgical challenge allowing favorable oncological outcomes

e16557

Background: In the current era of Immune checkpoint inhibitors (ICI), the role and timing of nephrectomy is still unknown. We aimed to evaluate the oncological outcomes of patients with metastatic renal cell carcinoma (mRCC) managed with nephrectomy for residual disease after complete response (CR) or major partial response (mPR defined as > 80%) on metastatic sites following ICI. Methods: Patients who underwent nephrectomy after prior ICI between 2015 and 2020 were retrospectively included and clinicopathological data were reviewed. Perioperative data, postoperative complications, toxicities related to ICI, continuation or discontinuation of systemic treatment following surgery, and 1-year oncological outcomes were recorded. Results: Twenty-five patients without initial cytoreductive nephrectomy at diagnosis underwent delayed nephrectomy after long ICI administration because of CR (or mPR) on metastatic sites. Median age was 62 years [38-79]. 88% of patients had clear cell RCC on the initial biopsy. IMDC prognostic group was intermediate (80%) or poor (20%). ICI was administered as first-line therapy in 56.0% of cases and as second-line option after TKI in 44.0% of cases. Treatments regimens were: nivolumab + ipilimumab (n = 12), nivolumab + tivozanib (n = 2) or nivolumab alone (n = 11). The mean duration of ICI treatment was 11.8 months (range: 3-38 months) and the mean number of cycles was 19 (range: 6-75). Twelve patients had a CR on metastatic sites while 13 patients had a mPR ( > 80%). Overall, 64% of patients experienced toxicities related to ICI treatment. Median operative time was 210 minutes [90-345] and mean blood loss was 558 cc [40-4000]. In 80.0% of cases, surgeons experienced difficulties in finding dissection plans due to adhesions and/or inflammatory infiltration. The 30-day Clavien-Dindo postoperative complication rate was 36.0%, including 1 surgery-related death. Pathological report showed lymphocyte and/or macrophage infiltration in 60% of cases and complete pathological response (pT0) in 3 cases (12%). After a mean follow-up of 19.4 months, 79.2% of the patients were free from progression and 70.8% free from systemic treatment. The recurrence-free survival (RFS) and overall survival (OS) at 1 year were 79.5% and 89.8% respectively. CR on metastatic sites was significantly associated with good RFS compared to mPR (1-year RFS = 100% vs. 56.8%, median RFS = 21.6 vs. 4.25 months, p = 0.006) while the duration of IO treatment exposure was not. Conclusions: Nephrectomy following ICI for mRCC can be a difficult procedure. However, it may provide good long-term RFS, with systemic treatment discontinuation following surgery in most cases. This strategy may be offered in well-selected patients, especially in case of CR on metastatic sites before surgery.

A phase 3 trial with a 2x2 factorial design of abiraterone acetate plus prednisone and/or local radiotherapy in men with de novo metastatic castration-sensitive prostate cancer (mCSPC): First results of PEACE-1

5000

Background: Historically, androgen deprivation therapy (ADT) was the standard of care (SOC) for men with mCSPC. Since 2015, combining ADT with either docetaxel, novel hormonal therapies, or radiotherapy to the primary tumor (RXT) (for those with low burden metastases) was shown to improve overall survival (OS) and thus has become the new SOC. It is unknown whether combining these new treatments on top of ADT further increments outcomes. Methods: Men with de novo mCSPC were randomized to SOC, SOC + abiraterone acetate-prednisone (abiraterone), SOC + RXT, or SOC + abiraterone + RXT. SOC was initially ADT alone, then from Oct 2015 onwards the use of docetaxel was authorized as part of SOC (at the investigator’s discretion until 2017, then, following the publication of the LATITUDE and STAMPEDE trials, accrual was restricted to men receiving ADT+docetaxel). The trial has two co-primary endpoints of radiographic progression-free survival (rPFS) and OS with type I error of 0.1% and 4.9%, respectively. The required number of rPFS events to achieve 80% power has been reached for the abiraterone question (not yet for the RXT question). The interaction between abiraterone and RXT was first tested using a Cox model adjusted for stratification factors (performance status, type of castration, metastatic burden, and when applicable, docetaxel). A hierarchical testing was used to test the effect of abiraterone: overall population, then ADT+docetaxel population. Results: From Nov 2013 to Dec 2018, 1173 men were enrolled (SOC was ADT+docetaxel in 710 pts and ADT alone in 463 pts), median age 67y (IQR: 60-72), high volume 57%, low volume 43%. The median follow-up is 3.5y. No interaction was detected between the effect of abiraterone and that of RXT (p = 0.64), allowing to pool abiraterone arms for comparisons. rPFS was significantly improved in the abiraterone arm in the overall population (HR: 0.54 (0.46-0.64), p < 0.0001; medians: 2.2 vs 4.5 years) and in the ADT+docetaxel population: (HR: 0.50 (0.40-0.62), p < 0.0001; medians: 2.0 vs 4.5 years). bPFS (PFS including PSA progression as an event) also significantly favored abiraterone in the overall population (HR: 0.40 (0.35-0.47), p < 0.0001; medians: 1.5 vs 3.8 years) and in the ADT+docetaxel population (HR: 0.38 (0.31-0.47), p < 0.0001; medians: 1.5 vs 3.2 years). OS is maturing. Grade 3-4 adverse events reported in > 5% of pts within the first 6 months in the ADT+docetaxel population included neutropenic fever (4.5% vs 5.4%), liver toxicity (19.7% vs 13%), and hypertension (12.2% vs 8.6%) in the abiraterone and control arms, respectively. Conclusion: Adding abiraterone to ADT + docetaxel significantly improves rPFS in men with de novo metastatic prostate cancer, with about 2.5 years of absolute benefit in medians, and no meaningful additional short-term toxicity. Clinical trial information: NCT01957436.

ODENZA: A French prospective, randomized, open-label, multicenter, cross-over phase II trial of preference between darolutamide and enzalutamide in men with asymptomatic or mildly symptomatic metastatic castrate-resistant prostate cancer (CRPC)

5046

Background: Darolutamide (Daro) and enzamutamide (Enza) are both next generation androgen receptor inhibitors with demonstrated activity in men with CRPC. Although both agents are associated with survival improvement, their toxicity profiles are different. To help decipher whether this may impact on patient preference, we designed the ODENZA trial. Methods: ODENZA is a prospective, randomized, open-label, multicenter, cross-over, phase II trial of preference between Daro and Enza in men with asymptomatic or mildly symptomatic metastatic CRPC. Patients were randomized 1/1 to receive Daro 1200 mg/d for 12 weeks followed by Enza 160 mg/d for 12 weeks (Daro-Enza arm) or the reverse sequence (Enza-Daro arm). In both arms, the second treatment was given in absence of evidence of cancer progression at week 12. The primary endpoint was patient preference between the two drugs, as assessed by a questionnaire at week 24. The Prescott's test was used to determine treatment preference in patients fullfilling pre planned criteria (exposure to both treatments, no progression at week 12, and completion of the preference questionnaire). A p-value greater than 0.05 indicates that there is no difference in preference between treatments. Stratification factors were performance status and prior taxane for mCSPC. After week 24, patients went on to an extension period during which they received the chosen treatment until progression or toxicity. The main secondary objectives included reasons for preference, response at week 12, cognitive assessment, and toxicity. Results: Overall 249 pts were randomized, median age 72y (68; 79), ECOG PS 0 (56%), prior taxanes (22%). Two hundred pts fulfilled the pre-planned criteria for evaluation of the preference primary endpoint : 97 (48.5% [41.3;55.7]), 80 (40.0% [33.0;47.0]), and 23 (11.5% [6.8;16.2]) chose Daro, Enza, and had no preference, respectively (unilateral p-value of 0.92). After preference assessment, 186 patients entered the extension period: 103 (55.4%) and 83 (44.6%) received Daro and Enza respectively. The most common factors influencing patient preference all numerically favored Daro over Enza, without significant differences were: less fatigue (44% vs 29%), ease of taking the medication (37% vs 31%), better quality of life (36% vs 28%), ability to be more active (26% vs 15%), ability to concentrate (22% vs 15%) and less falls (6% vs 3%). A PSA50 response was achieved in 76.2% and 83.9% at week 12 with Daro and Enza respectively (p = 0.13). Fatigue was the most frequently reported all grade adverse event at week 12, in 21% and 36% with Daro and Enza, respectively. Conclusions: More patients with early mCRPC preferred Daro over Enza, although the difference did not reach significance, with fatigue as the key influencing factor. Clinical trial information: NCT03314324.

Prostate cancer and PARP inhibitors: progress and challenges

Despite survival improvements achieved over the last two decades, prostate cancer remains lethal at the metastatic castration-resistant stage (mCRPC) and new therapeutic approaches are needed. Germinal and/or somatic alterations of DNA-damage response pathway genes are found in a substantial number of patients with advanced prostate cancers, mainly of poor prognosis. Such alterations induce a dependency for single strand break reparation through the poly(adenosine diphosphate-ribose) polymerase (PARP) system, providing the rationale to develop PARP inhibitors. In solid tumors, the first demonstration of an improvement in overall survival was provided by olaparib in patients with mCRPC harboring homologous recombination repair deficiencies. Although this represents a major milestone, a number of issues relating to PARP inhibitors remain. This timely review synthesizes and discusses the rationale and development of PARP inhibitors, biomarker-based approaches associated and the future challenges related to their prescription as well as patient pathways.

Adaptation of chemotherapy to the decline tumor markers in patients with poor prognosis nonseminomatous germ cell tumors:Real-world French experience

385

Background: Personalized chemotherapy based on tumor marker decline is the new standard in poor prognosis germ-cell tumor in Europe since 2014 (GETUG 13, Lancet, Fizazi et al). The purpose of this study was to analyze the reproducibility of the princeps study in patients not selected in clinical routine between 2014 and 2018. Methods: Patients (pts) were eligible if they had at least one criteria of IGCCCG classification for poor prognosis group. They had to be treated according the study terms of GETUG 13 study and did not received prior treatment. They had to received 1 BEP (Bleomycin, Etoposide, Cisplatin). Tumor markers (HCG and AFP) were dosed between day 18 and 21. Then, they received 3 additional BEP if they had favorable tumor marker decline or intensive chemotherapy if they had unfavorable decline. Results: This retrospective study included 104 patients in 14 french centers treated between 2013 and 2018: 22,1 % (n = 23) in the favorable group (Fav), 77,9 % (n = 81) in the unfavorable group (Unfav). Thirty-two pts had PS ≥ 2. In Unfav, there were more pts with HCG > 50 000 UI/L (44,2 % vs 13 %, p = 0,0067), neutrophil-to-lymphocyt ratio was also higher (median 6,4 vs 4,5, p = 0,0199). At cycle 1, all pts received BEP in Fav and 87,5 % (n = 70) in Unfav. After chemotherapy and surgery, 65,2 % in Fav and 41,3 % in Unfav obtained complete response. At 30 months (median follow-up), Fav-OS was 80,5 % (IC95% 55,8 – 92,2) and Unfav-OS was 64,4 % (IC95% 52 – 74,4). At 30 months, rates were 69,6 % (IC95% 46,6 -84,2) and 63.5 % (IC95% 51,9 – 73) respectively. In GETUG 13 study, 3-years OS was 84 % in Fav and 73 % on Unfav; 3-years PFS was 70 % and 59 % respectively. Seven pts died because of toxicity in Unfav (No one in Fav). Neuropathy, anemia and thrombopenia were more frequent in Unfav. Salvage high-dose chemotherapy with stem-cell transplant was required in 4 (66,7 %) pts in Fav and 8 (36,4 %) pts in Unfav. Conclusions: This study showed a reproducibility of the princeps study in terms of PFS and OS. Toxicity seemed more important in real world. For the congress, results will be reported with 50 additional pts.

An open-label, multicenter, phase IIIb study of patients with urinary tract carcinoma (UTC) (STRONG): Final analysis for fixed-dose durvalumab monotherapy (module A)

429

Background: Patients (pts) with advanced UTC who fail first-line therapy have poor prognoses. Durvalumab (D; anti-PD-L1) 10 mg/kg every 2 weeks is approved for treatment of metastatic urothelial carcinoma (mUC) after progression on platinum-based chemotherapy (CT). Further understanding of long-term safety and efficacy of D in platinum and non-platinum pretreated pts, using a fixed dose every 4 weeks (Q4W), is of value. Methods: Module A of the phase IIIb STRONG study (NCT03084471) investigated the safety of fixed-dose D (1500 mg, Q4W) in pts with urothelial and nonurothelial UTC who progressed on or after platinum/non-platinum CT. The primary endpoint was the number of pts with adverse events of special interest (AESIs) – events with an inflammatory or immune-mediated mechanism that may require interventions (eg, steroids/immunosuppressants), including immune-mediated adverse events (imAE). AEs with onset date on or after the date of first dose and up to 90 days after study discontinuation were included. Secondary endpoints included serious AEs and overall survival (OS). Exploratory endpoints included objective response rate (ORR) and disease control rate (DCR) (investigator assessed per RECIST 1.1). Results: A total of 867 pts received D monotherapy. Median age was 68.1 yr and 80.0% were male; 87.1% had an ECOG PS 0-1 and 12.7% had ECOG PS 2. Most (96.3%) had urothelial UTC, including urothelial variants. Tumor PD-L1 expression was high (≥25%) in 239/577 (41.4%) pts with available data. Median treatment and follow-up duration were 12.1 wk (range 1-128) and 13.8 mo (range 0.0-28.8), respectively. Safety data are reported in the table. Deaths related to study treatment occurred in 9 pts (1.0%). At data cutoff (March 31, 2020), 30.8% of pts were in survival follow-up. Median OS was 7.0 mo (95% CI: 6.4-8.2); OS rate at 1 and 2 yr was 35.8% (95% CI: 32.5-39.2) and 20.2% (95% CI: 16.5-24.1), respectively. ORR was 17.7% with complete responses in 5.1% of pts. DCR at 6 mo was 33.0%. Median OS of subgroups: PD-L1 high or low: 9.3 mo (95% CI: 6.7-12.7) and 6.5 mo (95% CI: 5.8-8.1); ECOG PS 0-1 or 2: 8.4 mo (95% CI: 7.2–9.8) and 3 mo (95% CI: 2.0-4.1); urothelial and nonurothelial UTC: 7.0 mo (95% CI: 6.4-8.2) and 7.0 mo (95% CI: 2.7-10.2), respectively. Conclusions: Fixed-dose D monotherapy Q4W is convenient with an acceptable safety profile in previously treated pts for UTC. Long-term safety and efficacy data reported are consistent with published studies of D and other IO agents in this setting. Clinical trial information: NCT03084471 . [Table: see text]

[Plan of the day adaptive radiotherapy for bladder cancer: Dosimetric and clinical results]

PURPOSE

To account of individual intra-pelvic anatomical variations in muscle invasive bladder cancer (MIBC) irradiation, adaptive radiotherapy (ART) using a personalized plan library may have dosimetric and clinical benefits.

MATERIAL AND METHODS

The data from ten patients treated for localized MIBC according to the "plan of the day" (P0oD) individualized ART technique were collected and retrospectively analysed. Target volumes and organs at risk (OAR) were delineated at different bladder fill rates, resulting in two or three treatment plans. Daily Cone-Beam CT (CBCT) was used for the selection of PoD at each fraction. Retrospectively, we delineated rectal, intestinal and target volumes on each CBCT, to assess target volume coverage and dose sparing to healthy tissues. A comparison with the conventional radiotherapy technique was performed. The secondary objectives were toxicity and efficacy.

RESULTS

The target coverage was respected with the adaptive treatment: 97.3% for the bladder Clinical Target Volume (CTV) (99.5; [60.1-100]) and 98% for the bladder+lymph nodes CTV (98.6; [85.4-100]). Concerning OAR, the volume of healthy tissue spared was 43.7% on average and the V45Gy for the small bowel was 43,4cc (35; [0-129]) (versus 57,6cc). The rectal D50 was on average 18,7Gy for the adaptive treatment (15.9; [2.4-44.1]) versus 17Gy with the conventional approach. With a median follow-up of 2.94 years (95% CI: [0.92-4.02]), we observed three grade 3 toxicities (30%). No grade 4 toxicity was observed. The 2-year overall survival and progression-free survival rates were 65.6% (95% CI: [26-87.6]) and 45.7% (95% CI: [14.3-73]), respectively.

CONCLUSION

The ART technique using a PoD strategy showed a reduction of the irradiated healthy tissue volume while maintaining a similar bladder coverage, with an acceptable rate of toxicity.

Survival with Olaparib in Metastatic Castration-Resistant Prostate Cancer

BACKGROUND

We previously reported that olaparib led to significantly longer imaging-based progression-free survival than the physician's choice of enzalutamide or abiraterone among men with metastatic castration-resistant prostate cancer who had qualifying alterations in homologous recombination repair genes and whose disease had progressed during previous treatment with a next-generation hormonal agent. The results of the final analysis of overall survival have not yet been reported.

METHODS

In an open-label, phase 3 trial, we randomly assigned patients in a 2:1 ratio to receive olaparib (256 patients) or the physician's choice of enzalutamide or abiraterone plus prednisone as the control therapy (131 patients). Cohort A included 245 patients with at least one alteration in BRCA1, BRCA2, or ATM, and cohort B included 142 patients with at least one alteration in any of the other 12 prespecified genes. Crossover to olaparib was allowed after imaging-based disease progression for patients who met certain criteria. Overall survival in cohort A, a key secondary end point, was analyzed with the use of an alpha-controlled, stratified log-rank test at a data maturity of approximately 60%. The primary and other key secondary end points were reported previously.

RESULTS

The median duration of overall survival in cohort A was 19.1 months with olaparib and 14.7 months with control therapy (hazard ratio for death, 0.69; 95% confidence interval [CI], 0.50 to 0.97; P = 0.02). In cohort B, the median duration of overall survival was 14.1 months with olaparib and 11.5 months with control therapy. In the overall population (cohorts A and B), the corresponding durations were 17.3 months and 14.0 months. Overall, 86 of 131 patients (66%) in the control group crossed over to receive olaparib (56 of 83 patients [67%] in cohort A). A sensitivity analysis that adjusted for crossover to olaparib showed hazard ratios for death of 0.42 (95% CI, 0.19 to 0.91) in cohort A, 0.83 (95% CI, 0.11 to 5.98) in cohort B, and 0.55 (95% CI, 0.29 to 1.06) in the overall population.

CONCLUSIONS

Among men with metastatic castration-resistant prostate cancer who had tumors with at least one alteration in BRCA1, BRCA2, or ATM and whose disease had progressed during previous treatment with a next-generation hormonal agent, those who were initially assigned to receive olaparib had a significantly longer duration of overall survival than those who were assigned to receive enzalutamide or abiraterone plus prednisone as the control therapy, despite substantial crossover from control therapy to olaparib. (Funded by AstraZeneca and Merck Sharp and Dohme; PROfound ClinicalTrials.gov number, NCT02987543.).