Characterization of Patients with Metastatic Renal Cell Carcinoma Undergoing Deferred, Upfront, or No Cytoreductive Nephrectomy in the Era of Combination Immunotherapy: Results from the International Metastatic Renal Cell Carcinoma Database Consortium

BACKGROUND

The role of cytoreductive nephrectomy (CN) has not yet been well characterized in the era of combination immunotherapy.

OBJECTIVE

To evaluate characteristics and outcomes for patients with metastatic renal cell carcinoma (mRCC) who received immuno-oncology (IO)-based combination therapy according to CN status.

DESIGN, SETTING, AND PARTICIPANTS

Using the International mRCC Database Consortium (IMDC), patients with mRCC who received frontline IO-based combinations were included. Upfront CN was defined as CN up to 3 mo before diagnosis of metastatic disease but before systemic therapy initiation. Deferred CN was defined as CN after systemic therapy initiation.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS

Overall survival (OS) from initiation of systemic therapy was estimated via Cox proportional-hazards regression. A 12-mo landmark time and a time-varying covariate for CN status were used to mitigate potential bias.

RESULTS AND LIMITATIONS

Of the 385 patients eligible for landmark analysis, 24, 182, and 179 underwent deferred CN, upfront CN, and no CN, respectively. Patients in the no CN subgroup were older (63 yr vs 57 yr in the deferred CN subgroup and 60 yr in the upfront CN subgroup; p = 0.001) and a higher proportion had bone metastases (44% vs 26% in the deferred CN subgroup and 23% in the upfront CN subgroup; p < 0.001). A lower proportion of patients in the upfront CN subgroup had IMDC poor risk (23% vs 43% in the no CN subgroup and 47% in the deferred CN subgroup; p < 0.001). On multivariable analysis, CN receipt was an independent favorable prognostic factor (hazard ratio 0.45, 95% confidence interval 0.26-0.78; p = 0.005). The study is limited by the lack of randomization and its retrospective nature.

CONCLUSIONS

Despite changes in practice patterns with the advent of novel therapeutic agents, CN may still serve as an effective surgical intervention in carefully selected patients.

PATIENT SUMMARY

For patients with metastatic kidney cancer, surgery to remove the primary tumor was traditionally the treatment of choice, but immunotherapy drugs are now another option for these patients. We analyzed data for contemporary patients with metastatic kidney cancer who received combination immunotherapy as their first treatment. We found that in selected patients receiving immunotherapy, surgery to remove the primary tumor as well can result in better prognosis.

Real-world Assessment of Clinical Outcomes in Patients with Metastatic Renal Cell Carcinoma with or Without Sarcomatoid Features Treated with First-line Systemic Therapies

BACKGROUND AND OBJECTIVE

Metastatic renal cell carcinoma (mRCC) patients have been reported to have better outcomes when treated with immunotherapies (IO) compared to targeted therapies (TT). This study aims to evaluate the impact of first-line systemic therapies on survival of mRCC patients with or without sarcomatoid features using real-world data.

METHODS

Metastatic RCC patients of International mRCC Database Consortium (IMDC) intermediate or high risk, diagnosed from January 2011 to December 2022, treated with first-line systemic therapies, and with histological documentation of the presence or absence of sarcomatoid features in nephrectomy specimens were identified using the Canadian Kidney Cancer information system. Patients were classified by initial treatment: (1) targeted therapy (TT) used alone or (2) immunotherapy (IO)-based systemic therapies used in combination of either IO-IO or IO-TT. The inverse probability of treatment weighting using propensity scores was used to balance for covariates. Cox proportional hazard models were used to assess the impact of initial treatment received on overall survival (OS).

KEY FINDINGS AND LIMITATIONS

Of the 1202 eligible patients, 791 were treated with TT and 411 with IO combinations. Of the patients, 76% were male, and the majority (91%) had a nephrectomy before systemic therapy. In nonsarcomatoid patients (639 TT and 320 IO patients), treatment with IO was associated with improved OS compared with patients treated with TT (median of 72 vs 48 mo, hazard ratio [HR] 0.63, 95% confidence interval [CI] 0.50-0.80, objective response rate [ORR] of 38.5% for IO and 23.5% for TT). In sarcomatoid patients (152 TT and 91 IO patients), treatment with IO was associated with improved OS (median of 48 vs 18 mo, HR 0.41, 95% CI 0.26-0.64, ORR of 49.5% for IO and 13.8% for TT). Similar results were observed in patients with synchronous metastatic disease only.

CONCLUSIONS AND CLINICAL IMPLICATIONS

IO treatment was associated with improved survival in mRCC patients. The magnitude of benefit is increased in patients with sarcomatoid mRCC, consequently, identifying the sarcomatoid status early on could help healthcare providers make a better treatment decision.

PATIENT SUMMARY

Metastatic renal cell carcinoma (mRCC) patients of International mRCC Database Consortium intermediate and high risk, diagnosed from January 2011 to December 2022, treated with first-line systemic therapies, and with histological documentation of the presence or absence of sarcomatoid features in nephrectomy specimens were identified using the Canadian Kidney Cancer information system (CKCis). In this study, treatment with immunotherapy was associated to an improved survival and response rates for mRCC patients with and without sarcomatoid features. The magnitude of benefit is increased in patients with sarcomatoid mRCC.

Impact of smoking status on clinical outcomes in patients with metastatic renal cell carcinoma treated with first-line immune checkpoint inhibitor-based regimens

BACKGROUND

Current tobacco smoking is independently associated with decreased overall survival (OS) among patients with metastatic renal cell carcinoma (mRCC) treated with targeted monotherapy (VEGF-TKI). Herein, we assess the influence of smoking status on the outcomes of patients with mRCC treated with the current first-line standard of care of immune checkpoint inhibitor (ICI)-based regimens.

MATERIALS AND METHODS

Real-world data from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) were collected retrospectively. Patients with mRCC who received either dual ICI therapy or ICI with VEGF-TKI in the first-line setting were included and were categorized as current, former, or nonsmokers. The primary outcomes were OS, time to treatment failure (TTF), and objective response rate (ORR). OS and TTF were compared between groups using the log-rank test and multivariable Cox regression models. ORR was assessed between the 3 groups using a multivariable logistic regression model.

RESULTS

A total of 989 eligible patients were included in the analysis, with 438 (44.3%) nonsmokers, 415 (42%) former, and 136 (13.7%) current smokers. Former smokers were older and included more males, while other baseline characteristics were comparable between groups. Median follow-up for OS was 21.2 months. In the univariate analysis, a significant difference between groups was observed for OS (P = .027) but not for TTF (P = .9), with current smokers having the worse 2-year OS rate (62.8% vs 70.8% and 73.1% in never and former smokers, respectively). After adjusting for potential confounders, no significant differences in OS or TTF were observed among the 3 groups. However, former smokers demonstrated a higher ORR compared to never smokers (OR 1.45, P = .02).

CONCLUSION

Smoking status does not appear to independently influence the clinical outcomes to first-line ICI-based regimens in patients with mRCC. Nonetheless, patient counseling on tobacco cessation remains a crucial aspect of managing patients with mRCC, as it significantly reduces all-cause mortality.

Characterization of Responses to Lenvatinib plus Pembrolizumab in Patients with Advanced Renal Cell Carcinoma at the Final Prespecified Survival Analysis of the Phase 3 CLEAR Study

In the phase 3 CLEAR trial, lenvatinib plus pembrolizumab (L + P) showed superior efficacy versus sunitinib in treatment-naïve patients with advanced renal cell carcinoma (aRCC). The combination treatment was associated with a robust objective response rate of 71%. Here we report tumor responses for patients in the L + P arm in CLEAR, with median follow-up of ∼4 yr at the final prespecified overall survival (OS) analysis. Tumor responses were assessed by independent review using Response Evaluation Criteria in Solid Tumors v1.1. Patients with a complete response (CR; n = 65), partial response (PR) with maximum tumor shrinkage ≥75% (near-CR; n = 59), or PR with maximum tumor shrinkage <75% (other PR; n = 129), were characterized in terms of their baseline characteristics. The median duration of response was 43.7 mo (95% confidence interval [CI] 39.2-not estimable) for the CR group, 30.5 mo (95% CI 22.4-not estimable) for the near-CR group, and 17.2 mo (95% CI 12.5-21.4) for the other PR group. The 36-mo OS rates were consistently high in the CR (97%), near-CR (86%), and other PR (62%) groups. Robust objective response rates were observed across International Metastatic RCC Database Consortium favorable-risk (69%, 95% CI 60-78%), intermediate-risk (73%, 95% CI 67-79%), and poor-risk (70%, 95% CI 54-85%) subgroups. The robust response to L + P supports this combination as a standard-of-care first-line treatment for patients with aRCC. PATIENT SUMMARY: The CLEAR trial enrolled patients with advanced kidney cancer who had not previously received any treatment for their cancer. Here we report results for tumor shrinkage observed in the group that received lenvatinib plus pembrolizumab combination treatment during the trial. Shrinkage of target tumors with this combination was long-lasting and was observed in patients irrespective of their disease severity. This trial is registered on ClinicalTrials.gov as NCT02811861.

Addressing controversial areas in the management of advanced prostate cancer in Canada Areas of consensus and controversy from the third Canadian consensus forum

INTRODUCTION

The management of prostate cancer (PCa) is rapidly evolving. Treatment and diagnostic options grow annually, however, high-level evidence for the use of new therapeutics and diagnostics is lacking. In November 2022, the Genitourinary Research Consortium held its 3rd Canadian Consensus Forum (CCF3) to provide guidance on key controversial areas for management of PCa.

METHODS

A steering committee of eight multidisciplinary physicians identified topics for discussion and adapted questions from the Advanced Prostate Cancer Consensus Conference 2022 for CCF3. Questions focused on management of metastatic castration-sensitive prostate cancer (mCSPC); use of novel imaging, germline testing, and genomic profiling; and areas of non-consensus from CCF2. Fifty-eight questions were voted on during a live forum, with threshold for "consensus agreement" set at 75%.

RESULTS

The voting panel consisted of 26 physicians: 13 urologists/uro-oncologists, nine medical oncologists, and four radiation oncologists. Consensus was reached for 32 of 58 questions (one ad-hoc). Consensus was seen in the use of local treatment, to not use metastasis-directed therapy for low-volume mCSPC, and to use triplet therapy for synchronous high-volume mCSPC (low prostate-specific antigen). Consensus was also reached on sufficiency of conventional imaging to manage disease, use of germline testing and genomic profiling for metastatic disease, and poly (ADP-ribose) polymerase (PARP) inhibitors for BRCA-positive prostate cancer.

CONCLUSIONS

CCF3 identified consensus agreement and provides guidance on >30 practice scenarios related to management of PCa and nine areas of controversy, which represent opportunities for research and education to improve patient care. Consensus initiatives provide valuable guidance on areas of controversy as clinicians await high-level evidence.

High-dose chemotherapy with autologous stem-cell transplantation for relapsed metastatic germ cell tumors The Alberta experience

INTRODUCTION

High-dose chemotherapy with autologous stem-cell transplantation (HDC-ASCT) is standard therapy for metastatic germ cell tumors (mGCTs) in patients whose disease progresses during or after conventional chemotherapy. We conducted a retrospective review of HDC-ASCT in relapsed mGCT patients in the province of Alberta, Canada, over the past two decades.

METHODS

Patients with mGCTs who received HDC-ASCT at two provincial cancer referral centers from 2000-2018 were identified from institutional databases. Baseline clinical and treatment characteristics were collected, as well as overall survival (OS ) and disease-free survival (DFS). Relevant prognostic variables were analyzed.

RESULTS

Forty-three patients were identified. The median age was 28 years (range 19-56). A majority (95%) had non-seminoma histology and testis/retroperitoneal primary (84%). Twenty patients (47%) had poor-risk disease, as per The International Germ Cell Consensus Classification (IGCCC), at start of first-line chemotherapy. HDC-ASCT was used as second-line therapy in 65% of patients, and 58% of ASCT patients received tandem transplants. Median followup after ASCT was 22 months (range 2-181). At last followup, 42% of patients were alive without disease, including 3/7 (43%) of patients with primary mediastinal disease. Two-year and five-year DFS/OS ratios were 44%/65% and 38%/45%, respectively. Median OS and DFS for all patients were 30.0 months (13.3-46.6) and 8.0 months (0.9-15.1), respectively.

CONCLUSIONS

We found that HDC-ASCT is an effective salvage therapy in mGCT, consistent with existing literature. Patients appeared to benefit regardless of primary site. Although limited by small sample size, we found a numerical difference in DFS and OS between second- and third-line HDC-ASCT and single vs. tandem ASCT.

Association of Cabozantinib Dose Reductions for Toxicity With Clinical Effectiveness in Metastatic Renal Cell Carcinoma (mRCC): Results From the Canadian Kidney Cancer Information System (CKCis)

BACKGROUND

Cabozantinib, an oral multi-targeted tyrosine kinase inhibitor (TKI), has demonstrated efficacy in metastatic renal cell carcinoma (mRCC). The association between toxicity and therapeutic effectiveness has been established with other TKIs. We investigated whether cabozantinib dose reductions, a surrogate for toxicity and adequate drug exposure, were associated with improved clinical outcomes in mRCC.

METHODS

Employing the CKCis database, we analyzed patients treated with cabozantinib in the second line or later between 2011 to 2021. The cohort was stratified into those needing dose reductions (DR) during treatment and those not (no-DR). Outcomes, including objective response rate (ORR), time to treatment failure (TTF), and overall survival (OS), were compared based on dose reduction status. The influence of the initial dose on outcomes was also explored.

RESULTS

Among 319 cabozantinib-treated patients, 48.3% underwent dose reductions. Response rates exhibited no significant difference between the DR and no-DR groups (15.1% vs. 18.2%, P = .55). Patients with DR had superior median OS (26.15 vs. 15.47 months, P = .019) and TTF (12.74 vs. 6.44 months, P = .022) compared to no-DR patients. These differences retained significance following adjustment for IMDC risk group (OS HR = 0.67, P = .032; TTF HR = 0.65, P = .008). There was no association between the initial dose and ORR, OS, or TTF.

CONCLUSION

This study highlights the link between cabozantinib dose reductions due to toxicity and improved survival and time to treatment failure in mRCC patients. These findings underscore the potential of using on-treatment toxicity as an indicator of adequate drug exposure to individualize dosing and optimize treatment effectiveness. Larger studies are warranted to validate these results and develop individualized strategies for cabozantinib when given alone or in combination with immunotherapy.

Outcomes of Patients with Brain Metastases from Renal Cell Carcinoma Receiving First-line Therapies: Results from the International Metastatic Renal Cell Carcinoma Database Consortium

Patients with brain metastases (BrM) from renal cell carcinoma and their outcomes are not well characterized owing to frequent exclusion of this population from clinical trials. We analyzed data for patients with or without BrM using the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC). A total of 389/4799 patients (8.1%) had BrM on initiation of systemic therapy. First-line immuno-oncology (IO)-based combination therapy was associated with longer median overall survival (OS; 32.7 mo, 95% confidence interval [CI] 22.3-not reached) versus tyrosine kinase inhibitor monotherapy (20.6 mo, 95% CI 15.7-24.5; p = 0.019), as were intensive focal therapies with stereotactic radiotherapy or neurosurgery (31.4 mo, 95% CI 22.3-37.5) versus whole-brain radiotherapy alone or no focal therapy (16.5 mo, 95% CI 10.2-21.1; p = 0.028). On multivariable analysis, IO-based regimens (HR 0.49, 95% CI 0.25-0.97; p = 0.040) and stereotactic radiotherapy or neurosurgery (HR 0.48, 95% CI 0.29-0.78; p = 0.003) were independently associated with longer OS, as was IMDC favorable or intermediate risk (HR 0.40, 95% CI 0.24-0.66; p < 0.001). Intensive systemic and focal therapies were associated with better prognosis in this population. Further studies should explore the clinical effectiveness of multimodal strategies. PATIENT SUMMARY: In a large group of patients with advanced kidney cancer, we found that 8.1% had brain metastases when starting systemic therapy. Patients with brain metastases had significantly poorer prognosis than those without brain metastases. Receipt of combination immunotherapy, stereotactic radiotherapy, or neurosurgery was associated with longer overall survival.

Pembrolizumab With or Without Lenvatinib for First-Line Metastatic NSCLC With Programmed Cell Death-Ligand 1 Tumor Proportion Score of at least 1% (LEAP-007): A Randomized, Double-Blind, Phase 3 Trial

INTRODUCTION

Lenvatinib plus pembrolizumab was found to have antitumor activity and acceptable safety in previously treated metastatic NSCLC. We evaluated first-line lenvatinib plus pembrolizumab versus placebo plus pembrolizumab in metastatic NSCLC in the LEAP-007 study (NCT03829332/NCT04676412).

METHODS

Patients with previously untreated stage IV NSCLC with programmed cell death-ligand 1 tumor proportion score of at least 1% without targetable EGFR/ROS1/ALK aberrations were randomized 1:1 to lenvatinib 20 mg or placebo once daily; all patients received pembrolizumab 200 mg every 3 weeks for up to 35 cycles. Primary end points were progression-free survival (PFS) per Response Evaluation Criteria in Solid Tumors version 1.1 and overall survival (OS). We report results from a prespecified nonbinding futility analysis of OS performed at the fourth independent data and safety monitoring committee review (futility bound: one-sided p < 0.4960).

RESULTS

A total of 623 patients were randomized. At median follow-up of 15.9 months, median (95% confidence interval [CI]) OS was 14.1 (11.4‒19.0) months in the lenvatinib plus pembrolizumab group versus 16.4 (12.6‒20.6) months in the placebo plus pembrolizumab group (hazard ratio = 1.10 [95% CI: 0.87‒1.39], p = 0.79744 [futility criterion met]). Median (95% CI) PFS was 6.6 (6.1‒8.2) months versus 4.2 (4.1‒6.2) months, respectively (hazard ratio = 0.78 [95% CI: 0.64‒0.95]). Grade 3 to 5 treatment-related adverse events occurred in 57.9% of patients (179 of 309) versus 24.4% (76 of 312). Per data and safety monitoring committee recommendation, the study was unblinded and lenvatinib and placebo were discontinued.

CONCLUSIONS

Lenvatinib plus pembrolizumab did not have a favorable benefit‒risk profile versus placebo plus pembrolizumab. Pembrolizumab monotherapy remains an approved treatment option in many regions for first-line metastatic NSCLC with programmed cell death-ligand 1 tumor proportion score of at least 1% without EGFR/ALK alterations.

Comparison of patients with renal cell carcinoma in adjuvant therapy trials to a real-world population

PURPOSE

To compare characteristics and outcomes of patients included versus those not in adjuvant therapy trials post complete resection of renal cell carcinoma (RCC).

METHODS

Adult patients following complete resection for clear cell RCC between January 1, 2011, and March 31, 2021, were included. Patients had intermediate high, high risk nonmetastatic disease (modified UCLA Integrated Staging System) or fully resected metastatic (M1) disease as per the inclusion criteria of adjuvant studies. Demographic, clinical, and outcomes between trial and nontrial patients were compared.

RESULTS

Of 1,459 eligible patients, 63 (4.3%) participated in an adjuvant trial. Disease characteristics were similar between groups. Trial patients were younger (mean age 58.1 vs. 63.6 years; P < 0.0001) and had lower Charlson Comorbidity Index scores (mean 4.2 vs. 4.9; P = 0.009). Unadjusted disease-free survival (DFS) at 5 years for trial patients was 48.6% and 39.2% for nontrial patients (HR 0.71, 0.48-1.05, P = 0.08). Median DFS was higher for trial patients in comparison to nontrial patients (4.4 years, IQR 1.7- not reached; vs. 3.0 years, IQR 0.8-8.6; P = 0.08). Cancer specific survival (CSS) at 5 years for trial patients was 85.2% in comparison to 78.6% for nontrial patients (HR 0.45, 0.22-0.92, P = 0.03). Unadjusted estimated overall survival (OS) at 5 years was 80.8% for trial patients and 74.8% (HR 0.42, 0.18-0.94; P = 0.04) for nontrial patients.

CONCLUSIONS

Patients in adjuvant trials were younger and healthier with longer CSS and OS in comparison to those not included in adjuvant trials. These findings may have implications when we generalize trial results to real world patients.

Adjuvant therapy for renal cell carcinoma: 2023 Canadian Kidney Cancer Forum consensus statement

INTRODUCTION

Several recent randomized trials evaluated the impact of adjuvant immune checkpoint inhibitor (ICI)-based therapy on post-surgical outcomes in renal cell carcinoma (RCC), with disparate results. The objective of this consensus statement is to provide data-driven guidance regarding the use of ICIs after complete resection of clear-cell RCC in a Canadian context.

METHODS

An expert panel of genitourinary medical oncologists, urologic oncologists, and radiation oncologists with expertise in RCC management was convened in a dedicated session during the 2022 Canadian Kidney Cancer Forum in Toronto, Canada. Topic statements on the management of patients after surgery for RCC, including counselling, risk stratification, indications for medical oncology referral, appropriate followup, eligibility and management for adjuvant ICIs, as well as treatment options for patients with recurrence who received adjuvant immunotherapy, were discussed. Participants were asked to vote if they agreed or disagreed with each statement. Consensus was achieved if greater than 75% of participants agreed with the topic statement.

RESULTS

A total of 22 RCC experts voted on 14 statements. Consensus was achieved on all topic statements. The panel felt patients with clear-cell RCC at increased risk of recurrence after surgery, as per the Keynote-564 group definitions, should be counselled about recurrence risk by a urologist, should be informed about the potential role of adjuvant ICI systemic therapy, and be offered referral to discuss risks and benefits with a medical oncologist. The panel felt that one year of pembrolizumab is currently the only regimen that should be considered if adjuvant therapy is selected. Panelists emphasized current opinions are based on disease-free survival given the available results. Significant uncertainty regarding the benefit and harms of adjuvant therapy remains, primarily due to a lack of consistent benefit observed across similar trials of adjuvant ICI-based therapies and immature overall survival (OS) data.

CONCLUSIONS

This consensus document provides guidance from Canadian RCC experts regarding the potential role of ICI-based adjuvant systemic therapy after surgery. This rapidly evolving field requires frequent evidence-based re-evaluation.

Characterization of Patients With Metastatic Renal Cell Carcinoma Experiencing Complete Response to First-line Therapies: Results From the International Metastatic Renal Cell Carcinoma Database Consortium

PURPOSE

Clinical trials have demonstrated higher complete response rates in the immuno-oncology-based combination arms than in the tyrosine kinase inhibitor arms in patients with metastatic renal cell carcinoma. We aimed to characterize real-world patients who experienced complete response to the contemporary first-line therapies.

MATERIALS AND METHODS

Using the International Metastatic Renal Cell Carcinoma Database Consortium, response-evaluable patients who received frontline immuno-oncology-based combination therapy or tyrosine kinase inhibitor monotherapy were analyzed. Baseline characteristics of patients and post-landmark overall survival were compared based on best overall response, as per RECIST 1.1.

RESULTS

A total of 52 (4.6%) of 1,126 and 223 (3.0%) of 7,557 patients experienced complete response to immuno-oncology-based and tyrosine kinase inhibitor therapies, respectively (P = .005). An adjusted odds ratio for complete response achieved by immuno-oncology-based combination therapy (vs tyrosine kinase inhibitor monotherapy) was 1.56 (95% CI 1.11-2.17; P = .009). Among patients who experienced complete response, the immuno-oncology-based cohort had a higher proportion of non-clear cell histology (15.9% and 4.7%; P = .016), sarcomatoid dedifferentiation (29.8% and 13.5%; P = .014), and multiple sites of metastases (80.4% and 50.0%; P < .001) than the tyrosine kinase inhibitor cohort. Complete response was independently associated with post-landmark overall survival benefit in both the immuno-oncology-based and tyrosine kinase inhibitor cohorts, giving respective adjusted hazard ratios of 0.17 (95% CI 0.04-0.72; P = .016) and 0.28 (95% CI 0.21-0.38; P < .001).

CONCLUSIONS

The complete response rate was not as high in the real-world population as in the clinical trial population. Among those who experienced complete response, several adverse clinicopathological features were more frequently observed in the immuno-oncology-based cohort than in the tyrosine kinase inhibitor cohort. Complete response was an indicator of favorable overall survival.

Evaluating the impact of early identification of asymptomatic brain metastases in metastatic renal cell carcinoma

BACKGROUND

Brain metastases (BM) in metastatic renal cell carcinoma (mRCC) have been reported to be present in up to 25% of patients diagnosed with mRCC. There is limited published literature evaluating the role of routine intra-cranial imaging for the screening of asymptomatic BM in mRCC.

AIMS

To evaluate the potential utility of routine intra-cranial imaging, a retrospective cohort study was conducted to characterize the outcomes of mRCC patients who presented with asymptomatic BM, as compared to symptomatic BM.

METHODS AND RESULTS

The Canadian Kidney Cancer Information System (CKCis) database was used to identify mRCC patients diagnosed with BM. This cohort was divided into two groups based on the presence or absence of BM symptoms. Details regarding patient demographics, disease characteristics, systemic treatments, BM characteristics and survival outcomes were extracted. Statistical analysis was through chi-square tests, analysis of variance, and Kaplan-Meier method to characterize survival outcomes. A p-value of <0.05 was considered statistically significant for all analyses. A total of 267 mRCC patients with BM were identified of which 106 (40%) presented with asymptomatic disease. The majority of patients presented with multiple (i.e., >1) BM (75%) with no significant differences noted in number of BM or BM-directed therapy received in symptomatic, as compared to asymptomatic BM patients. Median [95% confidence interval (CI)] overall survival (OS) from mRCC diagnosis was 42 months (95% CI: 32-62) for patients with asymptomatic BM, and 39 months (95% CI: 29-48) with symptomatic BM (p = 0.10). OS from time of BM diagnosis was 28 months (95% CI: 18-42) for the asymptomatic BM group, as compared to 13 months (95% CI: 10-21) in the symptomatic BM group (p = 0.04).

CONCLUSIONS

Given a substantial proportion of patients may present with asymptomatic BM, limiting intra-cranial imaging to patients with symptomatic BM, may be associated with a missed opportunity for timely diagnosis and treatment. The utility of routine intra-cranial imaging in patients with renal cell carcinoma, warrants further prospective evaluation.

Lenvatinib plus pembrolizumab versus sunitinib as first-line treatment of patients with advanced renal cell carcinoma (CLEAR): extended follow-up from the phase 3, randomised, open-label study

BACKGROUND

In the primary analysis of the CLEAR study, lenvatinib plus pembrolizumab significantly improved progression-free survival and overall survival versus sunitinib in patients with advanced renal cell carcinoma (data cutoff Aug 28, 2020). We aimed to assess overall survival based on 7 months of additional follow-up.

METHODS

This is a protocol-prespecified updated overall survival analysis (data cutoff March 31, 2021) of the open-label, phase 3, randomised CLEAR trial. Patients with clear-cell advanced renal cell carcinoma who had not received any systemic anticancer therapy for renal cell carcinoma, including anti-vascular endothelial growth factor therapy, or any systemic investigational anticancer drug, were eligible for inclusion from 200 sites (hospitals and cancer centres) across 20 countries. Patients were randomly assigned (1:1:1) to receive lenvatinib (20 mg per day orally in 21-day cycles) plus pembrolizumab (200 mg intravenously every 21 days; lenvatinib plus pembrolizumab group), lenvatinib (18 mg per day orally) plus everolimus (5 mg per day orally; lenvatinib plus everolimus group [not reported in this updated analysis]) in 21-day cycles, or sunitinib (50 mg per day orally, 4 weeks on and 2 weeks off; sunitinib group). Eligible patients were at least 18 years old with a Karnofsky performance status of 70 or higher. A computer-generated randomisation scheme was used, and stratification factors were geographical region and Memorial Sloan Kettering Cancer Center prognostic groups. The primary endpoint was progression-free survival assessed by independent imaging review according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). In this Article, extended follow-up analyses for progression-free survival and protocol-specified updated overall survival data are reported for the intention-to-treat population. No safety analyses were done at this follow-up. This study is closed to new participants and is registered with ClinicalTrials.gov, NCT02811861.

FINDINGS

Between Oct 13, 2016, and July 24, 2019, 1417 patients were screened for inclusion in the CLEAR trial, of whom 1069 (75%; 273 [26%] female, 796 [74%] male; median age 62 years [IQR 55-69]) were randomly assigned: 355 (33%) patients (255 [72%] male and 100 [28%] female) to the lenvatinib plus pembrolizumab group, 357 (33%) patients (275 [77%] male and 82 [23%] female) to the sunitinib group, and 357 (33%) patients to the lenvatinib plus everolimus group (not reported in this updated analysis). Median follow-up for progression-free survival was 27·8 months (IQR 20·3-33·8) in the lenvatinib plus pembrolizumab group and 19·4 months (5·5-32·5) in the sunitinib group. Median progression-free survival was 23·3 months (95% CI 20·8-27·7) in the lenvatinib plus pembrolizumab group and 9·2 months (6·0-11·0) in the sunitinib group (stratified hazard ratio [HR] 0·42 [95% CI 0·34-0·52]). Median overall survival follow-up was 33·7 months (IQR 27·4-36·9) in the lenvatinib plus pembrolizumab group and 33·4 months (26·7-36·8) in the sunitinib group. Overall survival was improved with lenvatinib plus pembrolizumab (median not reached [95% CI 41·5-not estimable]) versus sunitinib (median not reached [38·4-not estimable]; HR 0·72 [95% CI 0·55-0·93]).

INTERPRETATION

Efficacy benefits of lenvatinib plus pembrolizumab over sunitinib were durable and clinically meaningful with extended follow-up. These results support the use of lenvatinib plus pembrolizumab as a first-line therapy for patients with advanced renal cell carcinoma.

FUNDING

Eisai and Merck Sharp & Dohme.

Real-world utilization and outcomes of docetaxel among older men with metastatic prostate cancer: a retrospective population-based cohort study in Canada

BACKGROUND

The adoption of docetaxel for systemic treatment of metastatic prostate cancer (PCa), in both castration-sensitive (mCSPC) and castration-resistant (mCRPC) settings, is poorly understood. This study examined the real-world utilization of docetaxel in these patients and their outcomes.

METHODS

A retrospective population-based study used administrative data from Ontario, Canada, to identify men aged ≥66 years who were diagnosed with de novo mCSPC or mCRPC between 2014 and 2019 and received docetaxel. The study assessed treatment tolerability and toxicity, and survival in both cohorts. Descriptive and comparative statistical analysis were conducted.

RESULTS

The study identified 11.2% (399/3556) and 13.2% (203/1534) patients diagnosed with de novo mCSPC and with mCRPC who received docetaxel respectively. The median age in both cohorts was 72 years (IQR: 68-76). Overall, 43.9% (n = 175) patients with de novo mCSPC and 52.1% (n = 85) with mCRPC completed ≥6 cycles of docetaxel. Over two-fifth also needed dose adjustments in both cohorts. Hospitalization or emergency department visit for febrile neutropenia were noted in 15.8% (n = 63) of de novo mCSPC patients and similarly in 19% (n = 31) of mCRPC cohort. The median survival of PCa patients who completed ≥6 cycles of docetaxel was significantly longer relative to those who completed <4 cycles: 32.7 vs. 23.5 months (p < 0.001) for mCSPC and 20.5 vs. 10.7 (p = 0.012) for mCRPC respectively.

CONCLUSIONS

In this population-based study of elderly patients with metastatic PCa, treatment with docetaxel was associated with poor tolerability and higher toxicity compared with clinical trials. Receipt of limited cycles and reduced overall dose of docetaxel were associated with inferior overall survival.

Characterization of clinical outcomes among patients with advanced chromophobe renal cell carcinoma (ChRCC) treated with first-line immunotherapy (IO)-based regimens

654

Background: IO-based regimens have demonstrated substantial efficacy in the management of metastatic clear-cell RCC (mccRCC), where they currently represent the standard of care. ChRCC has a dismal prognosis in the metastatic setting. Recent clinical trials evaluating IO-based regimens across non-ccRCC subtypes identified a preliminary poor response in advanced ChRCC, but were limited by low sample sizes. We sought to comprehensively evaluate the outcomes of patients with ChRCC treated with IO-based regimens. Methods: Using real-world data from the International Metastatic RCC Database Consortium (IMDC), we conducted a retrospective analysis of patients with advanced ChRCC who received IO-based therapies, including dual IO therapy or IO + VEGF targeted therapy (VEGF-TT), in the first-line setting. The primary outcome was overall survival (OS). Secondary outcomes included time to treatment failure (TTF) and ORR. Cox proportional hazards models were used to adjust for age and IMDC risk groups as covariates. A logistic regression was used to determine the association between the odds of achieving a response and RCC subtype. Results: We identified 31 patients with advanced ChRCC and 856 patients with ccRCC treated with IO-based therapies in the first-line setting, with a median age of 61.5 years (IQR: 51.5-69.0). Compared to patients with ccRCC who received IO-based therapies as initial regimens, patients with ChRCC had a lower OS (median OS: 24.7 vs. 50.5 months, respectively; p<0.001) and a lower TTF (median TTF: 4.5 vs. 11.0 months, respectively; p<0.001). Among patients with an evaluable objective response, the ORR was lower among patients with advanced ChRCC, as opposed to those with ccRCC (ORR: 12.0 vs 47.1%, respectively; p<0.001). When evaluating first-line treatment with VEGF-TT monotherapy (sunitinib or pazopanib), no difference in outcomes was found between patients with ChRCC (n=122) and ccRCC (n=6,379) in relation to the primary endpoint of OS, while TTF and ORR suggested better outcomes for ccRCC (Table). Conclusions: In this real-world study, patients with metastatic ChRCC appear to display poor clinical outcomes even with IO-based regimens, as compared to ccRCC. The molecular determinants of poor response require further investigations. [Table: see text]

Impact of number of treatment lines following first-line (1L) immuno-oncology (IO) combination on overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC)

673

Background: Across the world, treatment of patients with mRCC is heterogeneous with different access to treatment sequences and number of lines of therapy (LOTs) employed. For instance, patients receiving first line (1L) nivolumab+ipilimumab (NIVO+IPI) may be offered second-line (2L) and third line (3L) vascular endothelial growth factor receptor targeted kinase inhibitor (VEGFR-TKI), whereas patients receiving 1L pembrolizumab or avelumab in combination with axitinib (IO+AXI) may only receive one subsequent VEGFR-TKI in 2L. We aimed to examine whether these different treatment strategies impact overall survival (OS). Methods: Adult mRCC patients who received at least three LOTs starting with 1L NIVO+IPI or at least two LOTs starting with 1L IO+AXI from the International Metastatic RCC Database Consortium (IMDC) centers were included. Kaplan-Meier analyses were used to estimate median OS (time from 1L to death). Results were stratified by 1L IMDC prognostic risk. Results: Among 128 patients who received at least three LOTs starting with 1L NIVO+IPI (median age 61 years, 77% White, 77% male, 37% from the US), 14% had favorable, 61% had intermediate, and 26% had poor IMDC risk. The most common 2L treatments following 1L NIVO+IPI were sunitinib (38%), cabozantinib (27%), and pazopanib (20%). Among 104 patients who received at least two LOTs starting with 1L IO+AXI (median age 62 years, 75% White, 67% male, 38% from the US), 28% had favorable, 48% had intermediate, and 25% had poor IMDC risk. The most common 2L treatments following 1L IO+AXI were cabozantinib (57%) and sunitinib (10%). Median OS are presented in the table, which suggested no difference in survival for patients who received at least two LOTs starting with 1L IO+AXI compared to patients who received at least three LOTs starting with 1L NIVO+IPI. Conclusions: Treatment for patients with mRCC varies depending on the 1L regimen chosen and by country. Our results demonstrate that, even with potential guaranteed time bias and IMDC imbalances, there is no statistically significant difference in OS for patients who received at least three LOTs starting with 1L NIVO+IPI and patients who received at least two LOTs starting with 1L IO+AXI, suggesting that selecting effective treatments in 1L resulting in fewer LOTs may have similar clinical outcomes as multiple LOTs. [Table: see text]

Phase II trial of cytoreductive stereotactic hypofractionated radiotherapy with combination ipilimumab/nivolumab for metastatic kidney cancer (CYTOSHRINK)

TPS750

Background: Randomized data from the interferon era demonstrated survival benefits of cytoreductive nephrectomy (CN) in patients with metastatic renal cell carcinoma (mRCC). Results from SURTIME and CARMENA, conducted in the VEGF-targeted therapy era, have challenged the routine use of upfront CN in most IMDC intermediate and poor risk patients. Furthermore, the treatment landscape in mRCC now includes multiple first-line doublet combination immunotherapy approvals. The Checkmate-214 trial showed that intermediate/poor risk patients have improved overall survival and durable objective responses with ipilimumab and nivolumab (I/N) compared to sunitinib. However, patients with a primary kidney lesion in situ appeared to have less benefit than patients with prior nephrectomy. Stereotactic body radiation therapy (SBRT) provides a convenient method for cytoreduction of the primary kidney lesion and may induce an enhanced systemic anti-tumor immune response. We hypothesize that SBRT to the primary kidney mass will enhance the efficacy of I/N compared to standard of care I/N alone in this unique subset of de novo mRCC patients. We also hypothesize that the combination of SBRT and I/N will lead to upregulation of key components of immune modulation as well as unique perturbation of the host gut microbiome compared to I/N alone. Methods: This phase II trial randomizes untreated mRCC patients in a 2:1 fashion to I/N plus SBRT (30-40 Gy in 5 fractions) to the primary kidney mass between cycles 1 and 2 (experimental arm, E), versus standard of care I/N alone (standard arm, S). Eligible patients have biopsy-proven mRCC (any histology) and IMDC intermediate/poor risk disease. Patients with a primary kidney lesion ≥ 20cm, previous abdominal radiation precluding SBRT, or who have a contraindication to I/N are excluded. The primary objective is to compare the efficacy of I/N plus SBRT versus I/N alone, as determined by the hazard ratio for progression free survival (PFS). Secondary objectives include evaluation of safety, overall survival, objective response rate, and health-related quality of life. Exploratory analyses include: (1) immune and genomic profiling of liquid biopsies; (2) transcriptional profiling of baseline tumor biopsies; and (3) interrogation of the gut microbiome and bacterial functionality. Blood and fecal samples will be prospectively collected at baseline, prior to cycle 2 of each arm, and at time of disease progression or the 12-month mark, whichever comes first. Up to 78 patients will be enrolled under the assumption of an improved 12-month PFS from 50% (S) to 75% (E), using a two-sided α=0.1, power=80%, and accounting for loss-to-follow-up and stratification using IMDC criteria 1-2 vs 3-6. Trial is enrolling in Canada and Australia. Clinical trial information: NCT04090710 .

Outcomes of patients with brain metastases from renal cell carcinoma treated with first-line therapies: Results from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)

600

Background: The outcomes of patients with brain metastases from renal cell carcinoma (RCC) are not well characterized due to exclusion of these patients from clinical trials. Methods: Using the IMDC, patients with brain metastases from RCC at the initiation of first-line therapy were analyzed. Baseline patient characteristics, brain-directed local therapies, clinician assessment of best overall response as per RECIST 1.1, and overall survival (OS) were compared across first-line therapies, namely immuno-oncology (IO)-based combination therapy (IO/IO or IO/vascular endothelial growth factor (VEGF)) and anti-VEGF monotherapy (sunitinib or pazopanib). Results: The overall cohort of patients with brain metastases included 775 patients, consisting of 78/1298 (6.0%) and 697/8633 (8.1%) in the IO-based and anti-VEGF cohorts, respectively (p = 0.009). Among the baseline patient characteristics, only the proportion of patients receiving whole-brain radiotherapy differed significantly across the IO-based and anti-VEGF cohorts with proportions of 25.0% and 55.7%, respectively (p < 0.001). Best overall response in all disease sites was 3.4% complete response (CR), 25.9% partial response (PR), 39.7% stable disease (SD), and 31% progressive disease (PD) in the IO-based cohort, whereas it was 0.7% CR, 29.6% PR, 36.7% SD, and 33.0% PD in the anti-VEGF cohort (p = 0.223). The following factors were significantly associated with longer OS on multivariable analysis: IMDC favourable-/intermediate-risk (HR 0.49, 95% CI 0.37–0.65; p < 0.001), IO-based combination therapy (HR 0.51, 95% CI 0.29–0.92; p = 0.026), neurosurgery (HR 0.62, 95% CI 0.47–0.83; p = 0.001), and stereotactic radiosurgery (HR 0.64, 95% CI 0.49–0.84; p = 0.001). Conclusions: Patients with brain metastases receiving IO-based combination therapy may have longer OS than those receiving anti-VEGF monotherapy. Brain-directed local therapies including neurosurgery and stereotactic radiosurgery were associated with longer OS. [Table: see text]

Outcomes of first subsequent taxane (FST) therapy in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) who previously received docetaxel intensification (DI) for metastatic castration-sensitive prostate cancer (mCSPC)

72

Background: The management of advanced prostate cancer continues to rapidly evolve, particularly with earlier use of survival prolonging therapies in mCSPC. Though approved prior to the use of intensification therapy in mCSPC, taxane-based chemotherapies remain a relevant option for pts with mCRPC. However, there is little evidence determining outcomes of taxane chemotherapies as FST in mCRPC pts who received DI in mCSPC. The purpose of this study is to compare outcomes between the survival prolonging taxanes, docetaxel (D) and cabazitaxel (C), as FST after DI. Methods: New patient consults seen at the Cross Cancer Institute from 1 July 2014 to 31 Dec 2020 were reviewed. Pts were considered eligible if they received DI for mCSPC and then received either D or C in mCRPC. Variables of interest were collected from the electronic medical record. The primary endpoint was ≥50% PSA response at 12 weeks relative to baseline for FST. Secondary endpoints included OS from mCSPC diagnosis, as well as PFS and OS from FST start date. PSA responses were compared using chi-squared test and time-based endpoints were compared using the Kaplan-Meier method. Results: 34 pts were identified: D = 22, C = 12 as FST. 91.2% of pts (D 95.5% vs C 83.3%) received FST in 2nd line mCRPC. Median age at diagnosis (63.1 vs 67.1 yrs, p = 0.236) and median time to CRPC (18.6 vs 14.2 mos, p = 0.079) were similar for D and C, respectively. Median time to FST (24.1 vs 34.6 mos, p = 0.036) and OS from mCSPC diagnosis (30.9 vs 52.7 mos, p = 0.002) were significantly shorter for pts receiving C vs D. PSA responses occurred in 40.9% of pts treated with D compared to 25.0% treated with C (p = 0.645). There was no significant difference in median PFS (2.7 vs 3.5 mos, p = 0.727) or median OS (11.4 vs 8.1 mos, p = 0.132) from time of FST for pts treated with D vs C, respectively. Conclusions: Both D and C demonstrated activity as FST after DI in mCSPC. Pts who received C had shorter time to FST and OS from mCSPC. The reasons for this may reflect clinician preference for C in pts with aggressive or rapidly progressing disease. No difference was found in PSA response, PFS, or OS from FST with D compared to C. While limited by its retrospective nature and small sample size, this study suggests that D is active as FST despite treatment with DI in mCSPC.

Practice patterns and predictors of treatment intensification in patients with metastatic castration-sensitive prostate cancer

76

Background: In recent years, treatment intensification beyond androgen deprivation therapy (ADT) with several novel therapies have shown survival benefit in patients with metastatic castration-sensitive prostate cancer (mCSPC). Given the rapidly evolving landscape in mCSPC treatment, there is a need to better understand how treatment strategies fit in real-world clinical practice and are combined/sequenced with other available therapies. Methods: Using electronic medical records and administrative data, a population-based retrospective cohort study was conducted. Patients aged ≥18 years of age who were newly diagnosed with de novo mCSPC and initiated ADT post-diagnosis between 2010 to 2020 in Alberta, Canada, were included. Treatment intensification was defined as the receipt of apalutamide, abiraterone acetate, enzalutamide, or chemotherapy (e.g. docetaxel) within 180 days of ADT initiation. Results: A total of 2,515 de novo mCSPC were identified during study period with 2,098 (83%) patients initiating ADT post-diagnosis. Of those, 525 (25%) received intensification beyond ADT. The percentage of patients who were intensified was 3% in 2010-2013 and gradually increased to 67% in 2020. Between 2014-2017, docetaxel was the most common therapy for intensification, but its use decreased considerably in 2018-2020 with abiraterone acetate, apalutamide and enzalutamide becoming increasingly available in the mCSPC setting. Upon progression, 46% and 22% in the intensified group versus 38% and 13% in the ADT-alone group initiated one and two-lines of subsequent therapies respectively. Abiraterone acetate and enzalutamide were the most common subsequent therapy for both the intensified (32% and 31% respectively) and the ADT-alone (56% and 38% respectively) groups. Docetaxel (24%) was used as subsequent therapy among mCSPC patients who were intensified with oral systemic agents. In multivariable logistic regression analyses of patients diagnosed in 2014-2020, significant predictors of intensification were younger age at diagnosis, lower Charlson comorbidity index, greater number of metastatic sites, shorter time to ADT initiation, referral to a specialists/cancer centres, surgery or radiation prior to ADT, and more recent year of diagnosis (all p<0.05). Conclusions: In Alberta, Canada, there has been a considerable increase in the utilization of ADT intensification therapies that correspond with the timing of clinical trial data and approvals of novel agents. Early referral to specialists/cancer centres is warranted to intensify mCSPC treatment beyond ADT and to improve patients’ outcomes. [Table: see text]

Comparative outcomes of metastatic prostate cancer (mPC) patients (pts) with DNA damage response gene alterations (DDR-a): A single-center experience

169

Background: DDR-a are prevalent in mPC pts. The clinical behaviour of these pts is not well defined. We sought to investigate how DDR-a affects prognosis and treatment outcomes in mPC pts. Methods: Eligible pts were age ≥18 with mPC who had undergone germline (G) and/or somatic (S) next generation sequencing (NGS) at the Cross Cancer Institute 2016-2021. Pts were considered DDR-a if a pathogenic/likely pathogenic variant (P/LP-v) in a DDR gene was identified on G or S NGS; patients were considered DDR-p if no P/LP-v was identified on S NGS. Data from electronic medical records were collected. The primary endpoint was overall survival (OS) from diagnosis of mPC. Secondary endpoints included: OS and progression free survival (PFS) from initial diagnosis of prostate cancer (PC); PSA response after 12 weeks, and PFS and OS from the start time of 1st and 2nd line therapies. Time based endpoints were analyzed using the Kaplan-Meier (KM) method, and log-rank statistics were used to compare the KM curves. PSA responses were compared using chi-squared testing. Results: 23 DDR-a and 48 DDR-p pts were identified. The most frequent DDR-a were BRCA2 (n=11) and ATM (n=6). Baseline characteristics including age at diagnosis were similar between the two groups. 1st line systemic therapy was androgen deprivation therapy (ADT) alone in 73.9% of DDR-a and 77.0% of DDR-p. 2nd line therapy was abiraterone or enzalutamide in 65% of DDR-a and 92% of DDR-p. Olaparib was received by 52% of DDR-a pts. No difference in OS from mPC (65.7 vs 51.0 mos, p=0.487), OS from initial diagnosis (94.1 vs 88.9 mos, p=0.865), PFS on 1st line therapy (33.2 vs 31.0 mos, p=0.847), OS on 1st line therapy (85.6 vs 78.6 mos, (p=0.799) PFS on 2nd line therapy (8.4 vs 13.1 mos, p=0.569) or OS on 2nd line therapy (32.5 vs 35.8 mos, p=0.901) was seen for DDR-a vs DDR-p, respectively. PSA responses to 1st and 2nd line therapies were similar and will be presented as waterfall plots. Conclusions: In this single-center cohort, no difference in clinical characteristics or outcomes were seen in DDR-a compared to DDR-p pts. While this study is limited by small numbers and retrospective nature, it adds to the growing literature characterizing the clinical behaviour of DDR-a mPC. Collaborative efforts are required to better define this molecular cohort of pts.

Outcomes of partial nephrectomy for non-metastatic cT2 renal tumors: Results from a Canadian multi-institutional collaborative

690

Background: The role of partial nephrectomy (PN) is not well defined for cT2 renal cell carcinoma (RCC) as compared to radical nephrectomy (RN). The aim of this study was to examine oncological outcomes of PN as compared to RN for non-metastatic cT2 RCC. Methods: The Canadian Kidney Cancer information system was used to define patients who underwent surgery for non-metastatic cT2 RCC from January 2011 to October 2022. Patients with clear-cell, papillary, and chromophobe RCC were included. Other histology, multiple tumours, and hereditary RCC syndrome patients were excluded. Each PN patient was individually matched to RN up to 1:4 depending on availability of patients based on tumor size (+/- 1cm), histology, grade (clear cell and papillary), and necrosis (clear cell). Matched patients were analyzed as clusters. Results: A total of 1523 patients were identified, and 50 PN patients met study criteria who were then matched to 185 RN patients. Both groups had similar age, gender, smoking status, BMI, Charlson comorbidity index score, symptoms at presentation, baseline eGFR, hemoglobin and pathological characteristics. PN patients had smaller tumors (7.6 cm [IQR 2] vs 8.4 [IQR 2.4], p=0.05), had higher likelihood of undergoing open surgery (72.9% vs 31.8%, p<0.0001) and less likely received adrenalectomy (2% vs 24.3%, p=0.0004). Positive surgical margin rates were similar in both groups (8.2% in PN vs 3.4% in RN, p=0.2). Median follow up was not significantly different in either group (3.6 yrs [IQR 4.7] in PN vs 3.3 [4.7] yrs in RN, p=0.9). During the follow up period, PN patients had higher risk of local recurrence (HR 3.0, 95%CI 1.08-8.37), lower risk of distant metastasis (HR 0.36, 95%CI 0.15-0.88), better cancer specific survival (HR 0.56, 95%CI 0.18-1.78) and overall survival (HR 0.36, 95%CI 0.11-1.19) and as compared to RN. At 6 months and beyond after surgery, PN patients had less decline in eGFR than RN patients (-16.6 [SD 21.1] vs -24.4[SD 16.2], p=0.0002). Complications rates between PN and RN were (18% vs 9%, p=0.057). Conclusions: In this multi-institutional Canadian cohort of patients with non-metastatic cT2 RCC undergoing surgery, PN compared to RN was associated with slightly higher risk of peri-operative complications, better preservation of renal function, and higher risk of local recurrence. The lower risk of distant metastasis and death was likely from residual confounding unaccounted for in the individual patient match. [Table: see text]

A Comparison of Percutaneous Ablation Therapy to Partial Nephrectomy for cT1a Renal Cancers: Results from the Canadian Kidney Cancer Information System

PURPOSE

Percutaneous ablation therapy (AT) and partial nephrectomy (PN) are successful management strategies for T1a renal cancer. Our objective was to compare AT to PN with respect to recurrence-free survival (RFS) and overall survival (OS).

MATERIALS AND METHODS

Patients post-PN or -AT for cT1aN0M0 renal cancer from 2011 to 2021 were identified from the national Canadian Kidney Cancer information system. Inverse probability of treatment weighting (IPTW) using propensity score (PS) was used. The primary outcomes, RFS and OS, were compared using Kaplan-Meier log-rank test analyses and Cox proportional hazard regression models.

RESULTS

A total of 275 patients underwent AT and 2,001 underwent PN, with a median followup of 2.0 years (IQR 0.6-4.1). Covariates were well balanced between the AT and PN cohorts following PS matching. Two-year RFS following IPTW PS analysis for patients undergoing AT and PN was 88.1% and 97.4% (p <0.0001), respectively, while 2-year OS was 97.4% and 99.0% (p=0.7), respectively. Five-year RFS following IPTW PS analysis for patients undergoing AT and PN was 86.0% and 95.1%, respectively (p=0.003), while 5-year OS was 94.2% and 95.1%, respectively (p=0.9). Following IPTW PS analysis, treatment modality (PN vs AT) was a predictor of disease recurrence (HR 0.36, p=0.003) but not for OS (HR 0.96, p=0.9).

CONCLUSIONS

With short followup, PN offers better RFS than AT, although no significant difference in OS was detected following PS adjustments. Both modalities can be offered to appropriately selected patients while we await prospective randomized data.

Outcomes of Radiation Therapy Plus Immunotherapy in Metastatic Renal Cell Carcinoma: Results From the Canadian Kidney Cancer Information System

Purpose

With the integration of immunotherapy (IO) agents in the management of metastatic renal cell carcinoma (mRCC), there has been interest in the combined use with radiation therapy (RT). However, real world data are limited. The purpose of this study was to evaluate outcomes in patients with mRCC receiving both RT and IO compared with IO alone.

Methods and Materials

Data were collected from Canadian Kidney Cancer Information System from January 2011 to September 2019 across 14 academic centers. Patients with mRCC who received IO as first- or second-line therapy were included. RT was categorized as radical dose or palliative dose. Kaplan-Meier estimates were reported for overall survival (OS) and time to treatment failure. Cox proportional hazard models were used adjusted for age and International Metastatic RCC Database Consortium risk categories.

Results

In total, 505 patients were included in the study: 179 received RT + IO and 326 received IO alone. Two-year OS for the RT + IO group was 55.0% compared with 66.4% in the IO alone cohort (adjusted hazard ratio [aHR], 1.38; P = .07). At 2 years, 12.2% of the RT + IO patients remained on therapy versus 30.9% in the IO alone group (aHR, 1.30; P = .02). For patients receiving first-line therapy, 2-year OS in the RT + IO group was 56.4% versus 78.4% in the IO alone arm, though this difference was not statistically significant (aHR, 1.23; P = .56). For patients receiving radical dose and palliative dose, 2-year OS was 57.0% and 53.9%, respectively (aHR, 0.86; P = .63).

Conclusions

In this descriptive analysis, more than one-third of patients with mRCC received RT and demonstrated inferior outcomes compared with IO alone. Potential explanations include greater presence of adverse metastatic sites in those receiving RT. Prospective clinical trials evaluating potential benefits of RT in an IO era remain an important need.

Evolving landscape of first-line combination therapy in advanced renal cancer: a systematic review

Background:

Renal cell carcinoma (RCC) is a common malignancy with approximately 30% of cases diagnosed at the advanced or metastatic stage. While single-agent vascular endothelial growth factor-targeted therapy has been a mainstay of treatment, data from multiple phase III trials assessing first-line immune checkpoint inhibitor (ICI) combinations have demonstrated a significant survival benefit.

Methods:

A systematic search of the published and presented literature was performed to identify phase III trials assessing ICI combination regimens in RCC using search terms ‘immune checkpoint inhibitors’ AND ‘renal cell carcinoma,’ AND ‘advanced’.

Results:

Six phase III trials showed significant benefits for ICI combinations compared with sunitinib. Nivolumab plus ipilimumab significantly improved overall survival [OS; median, 47.0 versus 26.6 months, hazard ratio (HR) = 0.68, 95% confidence interval (CI) = 0.58–0.81, p < 0.0001) and progression-free survival (PFS; median 11.6 versus 8.3 months, HR = 0.73, 95% CI = 0.61–0.87, p = 0.0004) in International Metastatic renal cell carcinoma Database Consortium intermediate and poor-risk patients. OS was also significantly improved for ICI plus tyrosine kinase inhibitor combinations regardless of risk, including pembrolizumab plus either axitinib (HR = 0.73, 95% CI = 0.60–0.88, p < 0.001) or lenvatinib (HR = 0.66, 95% CI = 0.49–0.88, p = 0.005) and nivolumab plus cabozantinib (HR = 0.66, 95% CI = 0.50–0.87, p = 0.003). No new safety signals were identified.

Conclusions:

Phase III first-line trials of ICI combinations showed survival benefits compared with a control arm of sunitinib. Global access to these combinations should be made available to patients with advanced RCC.

Imaging Response to Contemporary Immuno-oncology Combination Therapies in Patients With Metastatic Renal Cell Carcinoma

IMPORTANCE

The association between treatment with first-line immuno-oncology (IO) combination therapies and physician-assessed objective imaging response among patients with metastatic renal cell carcinoma (mRCC) remains uncharacterized.

OBJECTIVE

To compare the likelihood of objective imaging response (ie, complete or partial response) to first-line IO combination ipilimumab-nivolumab (IOIO) therapy vs approved IO with vascular endothelial growth factor inhibitor (IOVE) combination therapies among patients with mRCC.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter international cohort study was nested in routine clinical practice. A data set from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) was used to identify consecutive patients with mRCC who received treatment with IO combination therapies between May 30, 2013, and September 9, 2021. A total of 899 patients with a histologically confirmed diagnosis of mRCC who received treatment with a first-line IOVE or IOIO regimen and had evaluable responses were included.

EXPOSURES

Best overall response to first-line IO combination therapy based on Response Evaluation Criteria in Solid Tumors, version 1.1.

MAIN OUTCOMES AND MEASURES

The primary outcome was the difference in treating physician-assessed objective imaging response based on the type of first-line IO combination therapy received. Secondary outcomes included the identification of baseline characteristics positively associated with objective imaging response and the association of objective imaging response with overall survival.

RESULTS

Among 1085 patients with mRCC who received first-line IO combination therapies, 899 patients (median age, 62.8 years [IQR, 55.9-69.2 years]; 666 male [74.2%]) had evaluable responses. A total of 794 patients had information available on IMDC risk classification; of those, 127 patients (16.0%) had favorable risk, 442 (55.7%) had intermediate risk, and 225 (28.3%) had poor risk. With regard to best overall response among all participants, 37 patients (4.1%) had complete response, 344 (38.3%) had partial response, 315 (35.0%) had stable disease, and 203 (22.6%) had progressive disease. Corresponding median overall survival was not estimable (95% CI, 53.3 months to not estimable) among patients with complete response, 55.9 months (95% CI, 44.1 months to not estimable) among patients with partial response, 48.1 months (95% CI, 33.4 months to not estimable) among patients with stable disease, and 13.0 months (95% CI, 8.4-18.1 months) among patients with progressive disease (log rank P < .001). Treatment with IOVE therapy was found to be independently associated with an increased likelihood of obtaining response (OR, 1.89; 95% CI, 1.26-2.81; P = .002) compared with IOIO therapy. The presence of lung metastases (odds ratio [OR], 1.49; 95% CI, 1.01-2.20), receipt of cytoreductive nephrectomy (OR, 1.59; 95% CI, 1.04-2.43), and favorable IMDC risk (OR, 1.93; 95% CI, 1.10-3.39) were independently associated with an increased likelihood of response.

CONCLUSIONS AND RELEVANCE

In this study, treatment with IOVE therapy was associated with significantly increased odds of objective imaging response compared with IOIO therapy. The presence of lung metastases, receipt of cytoreductive nephrectomy, and favorable IMDC risk were associated with increased odds of experiencing objective imaging response. These findings may help inform treatment selection, especially in clinical contexts associated with high-volume multisite metastatic disease, in which obtaining objective imaging response is important.

Patterns of care for non‐metastatic castration‐resistant prostate cancer: A population‐based study

Objectives

To describe patterns of practice of PSA testing and imaging for Ontario men receiving continuous ADT for the treatment of non‐metastatic castration‐resistant prostate cancer (nmCRPC).

Patients and Methods

This was a retrospective, longitudinal, population‐based study of administrative health data from 2008 to 2019. Men 65 years and older receiving continuous androgen deprivation therapy (ADT) with documented CRPC were included. An administrative proxy definition was applied to capture patients with nmCRPC and excluded those with metastatic disease. Patients were indexed upon progression to CRPC and were followed until death or end of study period to assess frequency of monitoring with PSA tests and conventional imaging. A 2‐year look‐back window was used to assess patterns of care leading up to CRPC as well as baseline covariates.

Results

At a median follow‐up of 40.1 months, 944 patients with nmCRPC were identified. Their median time from initiation of continuous ADT to CRPC was 26.0 months. 60.7% of patients had their PSA measured twice or fewer in the year prior to index, and 70.7% patients did not receive any imaging in the year following progression to CRPC. Throughout the study period, 921/944 (97.6%) patients with CRPC progressed to high‐risk (HR‐CRPC) with PSA doubling time ≤ 10 months, of which more than half received fewer than three PSA tests in the year prior to developing HR‐CRPC, and 30.9% received no imaging in the subsequent year.

Conclusion

PSA testing and imaging studies are underutilized in a real‐world setting for the management of nmCRPC, including those at high risk of developing metastatic disease. Infrequent monitoring impedes proper risk stratification, disease staging and detection of treatment failure and/or metastases, thereby delaying the necessary treatment intensification with life‐prolonging therapies. Adherence to guideline recommendations and the importance of timely staging should be reinforced to optimize patient outcomes.

Predictors of objective response to first-line immuno-oncology combination therapies in metastatic renal cell carcinoma: Results from the international metastatic renal cell database consortium (IMDC)

310

Background: Predictors of objective response to first-line (1L) immuno-oncology (IO) combination therapies remain elusive. We sought to characterise clinical variables and their association with investigator assessed best overall response. Methods: Using the IMDC, we retrospectively identified patients treated with 1L ipilimumab nivolumab (IPI-NIVO) or approved IO/vascular endothelial growth factor (VEGF) inhibitor combinations (IOVE). Patients were classified, per RECIST v1.1, as responders (complete or partial response (CR or PR)) or non-responders (stable or progressive disease (SD or PD)). Logistic regression was used to adjust for IMDC criteria. Results: Out of 1084 patients, 794 (73%) received IPI-NIVO and 290 (27%) received IOVE (axitinib+pembrolizumab, cabozantinib+nivolumab, axitinib+avelumab, lenvatinib+pembrolizumab). Favourable, intermediate and poor IMDC risk comprised 147 (16%), 517 (55%) and 272 (29%) respectively. Of the 898 patients with evaluable responses, 37 (4%) achieved a best response of CR, 343 (38%) PR, 315 (35%) SD and 203 (23%) PD. Corresponding median overall survival from time of 1L initiation was: not reached, 55.9, 48.1, and 13 months respectively (logrank p < 0.0001). In a multivariable model, lung metastases and cytoreductive nephrectomy (CN) (performed after diagnosis of metastatic disease and before 1L therapy) retained independent association with response, after adjustment for IMDC criteria. Factors not associated with response included (with univariable p values): gender (p = 0.58), age (p = 0.06), sarcomatoid histology (p = 0.99), smoking status (p = 0.39), liver (p = 0.63) and brain (p = 0.12) metastases. As in the VEGF monotherapy era, improved IMDC prognostic risk was associated with response. Results were similar when restricted to the IPI-NIVO cohort. Conclusions: Presence of lung metastases, CN and better IMDC risk group are associated with a higher probability of response to 1L immunotherapy combination regimens. Further work to identify reliable predictors of response to guide treatment selection and patient counselling is warranted.[Table: see text]

Characterizing IMDC prognostic groups in contemporary first-line combination therapies for metastatic renal cell carcinoma (mRCC)

308

Background: The combination of immuno-oncology agents (IO) ipilimumab and nivolumab (IPI-NIVO) and combinations of IO with vascular endothelial growth factor targeted therapies (IOVE) have demonstrated efficacy in clinical trials for the first-line treatment of mRCC. This study seeks to establish real-world clinical benchmarks based on the International mRCC Database Consortium (IMDC) criteria using vascular endothelial growth factor targeted therapy (VEGF-TT) treated patients for context. Methods: The IMDC database (IMDConline.com) was used to identify patients with mRCC who received first-line IPI-NIVO, IOVE (axitinib/pembrolizumab, lenvatinib/pembrolizumab, cabozantinib/nivolumab, or axitinib/avelumab) and VEGF-TT (sunitinib or pazopanib) from 2002-2021. The primary endpoint was overall survival (OS) and was calculated from time of initiation of first-line therapy to death or last follow up. Log-rank tests were conducted to compare favorable, intermediate, and poor risk OS outcomes within treatment groups. Overall response rates (ORR) and complete response (CR) rates were calculated based on physician assessment of best clinical response. Results: In total, 692 patients received IPI-NIVO, 244 received IOVE, and 7152 received VEGF-TT. Baseline characteristics for IPI-NIVO, IOVE, and VEGF-TT, respectively, were as follows: median age (interquartile range) 63 (56-69), 64 (57-70), and 63 (56-70); male 72%, 74%, and 72% (p=0.74); non-clear cell histology 15%, 10%, and 13% (p=0.15); sarcomatoid features 24%, 15%, and 13% (p<0.0001); brain metastasis 8%, 4%, and 8% (p=0.04); liver metastasis 18%, 14%, and 18% (p=0.17); underwent nephrectomy 61%, 79% and 80% (p<0.0001). OS and ORR are reported in the table. P-values (log rank) for OS between risk groups were significant for IPI-NIVO (p<0.0001), IOVE (p=0.0005), and VEGF-TT (p<0.0001). Conclusions: These findings provide real-world survival and response benchmarks for contemporary first-line mRCC treatments and could be helpful for patient counselling. In addition, these findings mirror the efficacy of combination therapies established in clinical trials against VEGF-TT monotherapy. IMDC criteria continue to risk stratify patients in these novel combination therapies.[Table: see text]

Comparison of patients with high-risk nonmetastatic clear cell renal carcinoma in adjuvant therapy trials versus nonclinical trial patients

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Background: Characteristics of patients with high risk for recurrence non-metastatic renal cell carcinoma (nmRCC) participating in adjuvant therapy clinical trials post-nephrectomy have not been well described. We evaluated high risk nmRCC patients in the CKCis database to explore differences between trial and non-trial patients. Methods: Adult patients undergoing partial or radical nephrectomy for clear cell nmRCC between January 1, 2011 and March 31, 2021 were included. CKCis is a prospective cohort of patients from 14 Canadian academic institutions. Patients with high risk nmRCC (using modified UCLA Integrated Staging System) were included. Demographic, clinical, and survival statistics were analyzed for all patients and comparatively for the trial and non-trial groups. Results: 1459 patients, including 63 in adjuvant trials, were evaluated. 71% were male, 91% had pT3N0M0 disease. Disease characteristics including tumor size, stage, grade, location, necrosis, and margin status were similar between groups. Trial patients were younger (mean age 58.1 vs. 63.6; p < 0.0001) and had lower Charlson Comorbidity Index scores (median 4 [3,6) vs. 5 [4,6] p < 0.001). Estimated overall survival (OS) at 5 years was 80.8% (95% CI, 65,90) for trial patients and 74.8% (95% CI, 71,78.2) for non-trial patients. Recurrence-free survival at 5 years for trial patients was 48.6% (95% CI, 34,61.7) and 39.2% (95% CI, 35.2,43.1) for non-trial patients. Conclusions: Patients in adjuvant trials were younger and healthier at baseline than the average high risk nmRCC CKCis patient. Trial patients appear to have had longer time to recurrence and longer survival compared to non-trial patients, although not reaching statistical significance. Selection bias is common in clinical trials and evaluation of real-world population-based evidence of patients receiving adjuvant therapy will be important to ensure phase 3 trial results have external validity.

Effectiveness of first-line therapy in patients with advanced non-clear renal cell carcinoma (nccRCC)

304

Background: Current treatment principles for advanced nccRCC have been largely extrapolated from guidelines for clear cell RCC. Given the emerging randomized data for select nccRCC subtypes, real-world outcomes for these patients are informative particularly in the contemporary checkpoint inhibitor era. Methods: We performed an analysis using the Canadian Kidney Cancer information system (CKCis), a prospective database involving 14 academic centers, on nccRCC patients undergoing first-line systemic therapy between January 2011 – December 2019. Treatment groups were defined as receipt of: vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGF-TKI), mammalian target of rapamycin inhibitors (mTORi), and PD-1/PD-L1 immune checkpoint inhibitors (ICI, mono- or combination therapy). Primary outcome was 1-yr overall survival (OS) rate. Secondary outcomes were median time to treatment failure ((TTF, months), defined as treatment discontinuation, change or death) and objective response rate (ORR, %). Results: We identified 265 nccRCC patients: 204 (77.0%) received VEGF-TKI, 19 (7.2%) received mTORi and 42 (15.8%) received ICI-based first-line therapy (Table). Overall, median age was 64 years, 75% were male, 84% were classified as IMDC intermediate/poor risk, and 16% underwent prior nephrectomy. Twenty-three percent of patients were enrolled in clinical trials. Patients received primarily sunitinib (81%) or pazopanib (15%) in the VEGF-TKI group (other: 4%), while mTORi-treated patients received temsirolimus (74%) or everolimus (26%). For the ICI-based treatment group, most patients received combination therapy as ipilimumab-nivolumab (71%) or pembrolizumab-axitinib (26%), with 3% receiving ICI monotherapy. 1-yr OS was 65.2% for VEGF-TKI, 57.9% for mTORi and 69.0% for ICI-treated patients. Median TTF was 3.3 for VEGF-TKI, 3.5 for mTORi and 7.1 mos for ICI-treated patients. ORR was 17%, 5%, and 37% respectively for the VEGF-TKI, mTORi and ICI-treated groups. Conclusions: We describe the effectiveness of first-line therapy for patients with nccRCC from a national database. This real-world data suggests an association between first-line ICI-based therapies and improved outcomes, albeit with cabozantinib not available for the indication during this time. Our data supports consensus recommendations for preferred use of ICI-based or VEGF-TKI over mTORi as first-line therapy in nccRCC.[Table: see text]

Efficacy of tyrosine kinase inhibitors (TKI) after combination ipilimumab plus nivolumab (I/N) in metastatic clear cell renal cell carcinoma (ccmRCC) patients: Results from the Canadian Kidney Cancer Information System (CKCis)

346

Background: The use of I/N is a proven first-line option for patients with intermediate/poor IMDC prognostic criteria. The use of vascular endothelial growth factor inhibitors such as sunitinib have shown activity in the treatment of ccmRCC, but their effectiveness post I/N needs better characterization. This study aims to demonstrate the efficacy of sunitinib, and other TKI agents post I/N in ccmRCC in a real world setting. Methods: Patients with ccmRCC who had received I/N and were subsequently treated with TKI between Jan 1, 2011 and December 31, 2019 were identified from CKCis. Time to treatment failure (TTF – time from start of first subsequent TKI to discontinuation for any reason) and overall survival (OS) – time from first subsequent TKI to death) were calculated using the Kaplan-Meier method. Cox regression was performed to adjust for IMDC criteria. RECIST criteria was used to determine best overall response (ORR) of TKI radiographically. Results: 64 patients were treated with TKI post I/N. Characteristics and outcomes are listed in the table. Of the second-line TKI patients, 51 received sunitinib, 10 received pazopanib and 3 received other TKI. Reasons for second-line TKI discontinuation are: 28% toxicity, 34% progression, 7% other reasons while 31% remain on treatment. Median follow-up time was 12.9m. ORR for second-line TKI overall and second-line sunitinib was 30.0% and 29.4%, respectively. Conclusions: These data show that TKI are active after I/N in ccmRCC. TTF may underestimate PFS due to the large number of patients discontinuing treatment for toxicity and not progression. Efficacy of second-line TKI post I/N in this dataset is similar that of first-line sunitinib from recent randomized phase III trials, suggesting that there may be no significant loss of TKI activity after having received first-line I/N. Overall, these data support the use of TKI after I/N.[Table: see text]

Association of cabozantinib dose reductions for toxicity with clinical effectiveness in metastatic renal cell carcinoma (mRCC): Results from the Canadian Kidney Cancer Information System (CKCis)

316

Background: Cabozantinib (cabo) is an oral multi-targeted tyrosine kinase inhibitor (TKI) with activity in mRCC. TKI toxicity, an indicator of adequate drug exposure, has been associated with clinical effectiveness for sunitinib, pazopanib, and axitinib. We explored whether cabo dose reductions (a surrogate for toxicity) were associated with improved clinical outcomes in mRCC. Methods: Using the CKCis database, we performed an analysis of patients treated with cabo in the second-line or later between 2011-2021. We divided the cohort into those needing a dose reduction (DR, defined as less than the starting dose at time of treatment discontinuation) and those who did not (no-DR). We compared outcomes by dose reduction status, including objective response rate (ORR), time to treatment failure (TTF), and overall survival (OS). Results: We identified 260 patients who received cabo, of which 103 (41.0%) needed a DR. Across all lines, the ORR was similar between the DR and non-DR groups: 19.6% vs. 18.9% (p = 0.903) respectively. The median TTF was 12.75 months (95% CI 10.38 – 17.64) in the DR group vs. 6.44 months (95% CI 5.49 – 8.67) in the no-DR group. After adjusting for IMDC risk, the hazard ratio (HR) for TTF comparing DR vs. no-DR was 0.69 (95% CI 0.50 - 0.97, p-value = 0.03). The median OS was 29.6 months (95% CI 19.58 – 42.64) in the DR group vs. 15.28 (95% CI 11.04 – 22.64) in the no-DR group. After adjusting for IMDC risk, the HR for OS comparing DR vs. no-DR was 0.65 (95% CI 0.43 - 0.98, p = 0.04). Conclusions: Cabozantinib dose reductions, a surrogate for toxicity and adequate drug exposure, appear to be associated with improved TTF and OS in mRCC. Toxicity driven/individualized dosing strategies for cabo alone and in combination with immunotherapy, warrant further investigation.[Table: see text]

Patterns of care for patients with non-metastatic castration-resistant prostate cancer: Population-based study in Ontario, Canada

53

Background: To describe patterns of practice of PSA testing and imaging for Ontario men receiving continuous androgen deprivation therapy (ADT) for the treatment of non-metastatic castration-resistant prostate cancer (nmCRPC). Methods: This was a retrospective, longitudinal, population-based study of administrative health data from 2008 to 2019. Men > 65 years old receiving continuous ADT with documented CRPC were included. An administrative proxy definition was applied to capture patients with nmCRPC patients and excluded those with metastatic disease. Patients were indexed upon progression to CRPC and were followed until death or end of study period to assess frequency of monitoring with PSA tests and conventional imaging. A 2-year look-back window was used to assess patterns of care leading up to CRPC, as well as baseline covariates. Results: At a median follow-up of 40 months, 944 patients with CRPC were identified. Their median time from initiation of ADT to CRPC was 26 months, 61% of patients had their PSA measured twice or fewer in the year prior to index and 71% patients did not receive any imaging in the year following progression to CRPC. Almost all patients (98%, n = 921/944) in the study progressed to high-risk CRPC (HR-CRPC) during the study period, of which more than half received fewer than 3 PSA tests in the year prior to progression to HR-CRPC, and 31% received no imaging in the subsequent year. Conclusions: PSA testing and imaging studies are under-utilized in a real-world setting for the management of nmCRPC, including those at high-risk of developing metastatic disease. Infrequent monitoring impedes proper risk stratification, disease staging, detection of treatment failure and/or metastases, likely delaying necessary treatment intensification with life-prolonging therapies. Adherence to guideline recommendations and the importance of timely staging should be reinforced to optimize patients’ outcome.

Real-World Use of Androgen-Deprivation Therapy: Intensification Among Older Canadian Men With de Novo Metastatic Prostate Cancer

BACKGROUND

Despite the wealth of evidence demonstrating the efficacy of treatment intensification beyond androgen-deprivation therapy (ADT) among patients with de novo metastatic castration-sensitive prostate cancer (mCSPC), little is known of its real-world use. This study examined the real-world uptake of ADT treatment intensification among older men in a large Canadian province.

METHODS

We performed a retrospective population-based cohort study using province-wide linked administrative data in Ontario, Canada. Patients 66 years of age and older with de novo mCSPC were included and their treatment with conventional ADT-based regimens, ADT plus next-generation androgen receptor axis-targeted therapy, and ADT plus docetaxel were identified and stratified by time.

RESULTS

From 2014 to 2019, 3556 patients were identified with de novo mCSPC. Most patients (n = 2794 [78.6%]) were treated with a conventional ADT regimen, whereas 399 (11.2%) patients received ADT intensification with docetaxel and 52 (1.5%) patients received abiraterone acetate plus prednisone. In a time-stratified analysis of ADT intensification before and after the pivotal AA+P trial (LATITUDE), AA+P uptake increased from 0.5% to 3.0%, whereas docetaxel use dropped from 12.0% to 10.0%. The median survival of the study population was 18 months (interquartile range = 10-31).

CONCLUSIONS

The majority of patients with de novo mCSPC are treated with ADT alone in the Canadian real-world setting, despite randomized clinical trial evidence of benefit with the use of ADT-intensified regimens. As ADT treatment intensification is substantially underused, better understanding of the barriers to treatment and targeted education to address them are needed.

Results from a Canadian consensus forum of key controversial areas in the management of advanced prostate cancer: Recommendations for Canadian healthcare providers

INTRODUCTION

Rapid progress in diagnostics and therapeutics for the management of prostate cancer (PCa) have created areas where high-level evidence to guide practice is lacking. The Genitourinary Research Consortium (GURC) conducted its second Canadian consensus forum to address areas of controversy in the management of PCa and provide recommendations to guide treatment.

METHODS

A panel of PCa specialists discussed topics related to the management of PCa. The core scientific committee finalized the design, questions and the analysis of the consensus results. Attendees then voted to indicate their management choice regarding each statement/topic. Questions for voting were adapted from the 2019 Advanced Prostate Cancer Consensus Conference. The thresholds for agreement were set at ≥ 75% for 'consensus agreement', > 50% for "near-consensus", and ≤ 50% for "no consensus".

RESULTS

The panel was comprised of 29 PCa experts including urologists (n=12), medical oncologists (n= 12), and radiation oncologists (n= 5). Voting took place for 65 pre-determined questions and three ad hoc questions. Consensus was reached for 34 questions, spanning a variety of areas including biochemical recurrence, treatment of metastatic castration-sensitive PCa, management of non-metastatic and metastatic castration-resistant PCa, bone health, and molecular profiling.

CONCLUSION

The consensus forum identified areas of consensus or near-consensus in more than half of the questions discussed. Areas of consensus typically aligned with available evidence, and areas of variability may indicate a lack of high-quality evidence and point to future opportunities for further research and education.

Active Surveillance in Metastatic Renal Cell Carcinoma: Results From the Canadian Kidney Cancer Information System

BACKGROUND

Active surveillance (AS) is a commonly used strategy in patients with slow-growing disease. We aimed to assess the outcomes and safety of AS in patients with metastatic renal cell carcinoma (mRCC).

PATIENTS AND METHODS

We used the Canadian Kidney Cancer information system (CKCis) to identify patients with mRCC diagnosed between January 1, 2011, and December 31, 2016. The AS strategy was defined as (1) the start of systemic therapy ≥ 6 months after diagnosis of mRCC, or (2) never receiving systemic therapy for mRCC with an overall survival (OS) of ≥1 year. Patients starting systemic treatment <6 months after diagnosis of mRCC were defined as receiving immediate systemic treatment. OS and time until first-line treatment failure (TTF) were compared between the two cohorts.

RESULTS

A total of 853 patients met the criteria for AS (cohort A). Of these, 364 started treatment >6 months after their initial diagnosis (cohort A1) and 489 never started systemic therapy (cohort A2); 827 patients received immediate systemic treatment (cohort B). The 5-year OS probability was significantly greater for cohort A than for cohort B (70% vs. 33.6%; P < .0001). After adjusting for International Metastatic RCC Database Consortium risk criteria and age, both OS (hazard ratio [HR] = 0.58; 95% confidence interval [CI], 0.47-0.70; P < .0001) and TTF (HR = 0.72; 95% CI, 0.60-0.85; P = .0002) were greater in cohort A1 compared with B. For cohort A1, the median time on AS was 14.2 months (range, 6-71).

CONCLUSIONS

Based on the largest analysis of AS in mRCC to date, our data suggest that a subset of patients may be safely observed without immediate initiation of systemic therapy.

Outcomes of patients with solid tumour malignancies treated with first-line immuno-oncology agents who do not meet eligibility criteria for clinical trials

BACKGROUND

Immuno-oncology (IO)-based therapies have been approved based on randomised clinical trials, yet a significant proportion of real-world patients are not represented in these trials. We sought to compare the outcomes of trial-ineligible vs. -eligible patients with advanced solid tumours treated with first-line (1L) IO therapy.

PATIENTS AND METHODS

Using the International Metastatic Renal Cell Carcinoma (RCC) Database Consortium and the Alberta Immunotherapy Database, patients with advanced RCC, non-small-cell lung cancer (NSCLC) or melanoma treated with 1L PD-(L)1 inhibition-based therapy were included. Trial eligibility was retrospectively determined as per commonly used exclusion criteria. The outcomes of interest were overall survival (OS), overall response rate (ORR), treatment duration (TD) and time to next treatment (TTNT).

RESULTS

A total of 395 of 1241 (32%) patients were deemed trial-ineligible. The main reasons for ineligibility based on preselected exclusion criteria were Karnofsky performance status <70%/Eastern Cooperative Oncology Group performance status >1 (40%, 158 of 395), brain metastases (32%, 126 of 395), haemoglobin < 9 g/dL (16%, 63 of 395) and estimated glomerular filtration rate <40 mL/min (15%, 61 of 395). Between the ineligible vs. eligible groups, the median OS, ORR, median TD and median TTNT were 10.2 vs. 39.7 months (p < 0.01), 36% vs. 47% (p < 0.01), 2.7 vs. 6.9 months (p < 0.01) and 6.0 vs. 16.8 months (p < 0.01), respectively. Subgroup analyses showed statistically significant inferior OS, TD and TTNT for trial-ineligible vs. -eligible patients across all tumour types. Adjusted hazard ratios for death in RCC, NSCLC and melanoma were 1.84 (95% confidence interval [CI] 1.22-2.77), 2.21 (95% CI 1.58-3.11) and 1.82 (95% CI 1.21-2.74), respectively..

CONCLUSIONS

Thirty-two percent of real-world patients treated with contemporary 1L IO-based therapies were ineligible for clinical trials. Although one-third of the trial-ineligible patients responded to treatment, the overall trial-ineligible population had inferior outcomes than trial-eligible patients. These data may guide patient counselling and temper expectations of benefit.

Real-Word Experience of Cabozantinib in Metastatic Renal Cell Carcinoma (mRCC): Results from the Canadian Kidney Cancer information system (CKCis)

BACKGROUND: Cabozantinib is an oral multitargeted tyrosine kinase inhibitor (TKI) that has demonstrated efficacy in metastatic renal-cell carcinoma (mRCC) randomized trials. OBJECTIVE: To explore the real-world effectiveness of cabozantinib in pretreated patients with mRCC, including patients who progressed on immune-oncology checkpoint inhibitor (ICI) therapy. METHODS: Using the Canadian Kidney Cancer information system (CKCis), patients with mRCC treated with cabozantinib monotherapy as second-line or later from January 1, 2011 to September 1, 2019 were identified. Patients were stratified based on line of cabozantinib received. We reported overall survival (OS), time to treatment failure (TTF) and disease control rate (DCR). Prognostic variables were analyzed using multivariable analysis. RESULTS: 157 patients received cabozantinib (median TTF 8.0 months; median OS 15.8 months): 37 (24%) in the second line (median TTF 10.4 months; median OS 18.9 months) 66 (42%) in third line (median TTF 5.9 months; median OS 13.3 months) and 54 (34%) in either 4th or 5th line (median TTF 9.4 months; median OS 16.8 months). One hundred sixteen patients (74%) received cabozantinib after prior ICI therapy (median TTF of 7.6 months; median OS of 15.8 months). DCR in all patients was 63% with 46%, 65% and 72% in 2nd line, 3rd line and 4th/5th line patients respectively. DCR in patients who received cabozantinib after prior ICI therapy was 64%. CONCLUSIONS: Cabozantinib is effective in a real-world, unselected population of mRCC patients, including in those who have progressed on prior ICI therapy, and in those exposed to multiple lines of therapy.

Prognostic association between common laboratory tests and overall survival in men with de novo metastatic castration-sensitive prostate cancer: A population-based study

149

Background: Despite significant advancements in the treatment of metastatic prostate cancer, a validated prognostic tool for patients with de novo metastatic castration-sensitive prostate cancer (mCSPC) is still lacking. Using population-based data from Ontario, Canada, we sought to examine the prognostic association between common laboratory tests and survival for patients with mCSPC. Methods: A population-based cohort of men aged 66 years and older diagnosed with de novo metastatic prostate cancer between 2014-2019 were included. We assessed the association between laboratory tests at the time of cancer diagnosis and overall survival (OS). Utilizing a complete case analysis, we used Cox proportional hazards models to assess the association between these laboratory tests and OS while adjusting for patient and disease characteristics. Results: A total of 3,556 men with de novo mCSPC were included. On multivariable analysis, there were significant associations between OS and neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, albumin, hemoglobin, PSA decrease and PSA nadir <0.1 ng/mL (please see table). Conclusions: Commonly available laboratory tests provide important prognostic information for patients with newly diagnosed mCSPC given demonstrated associations to overall survival. Apart from PSA kinetics, none of these baseline tests were performed in more than 57% of patients indicating underutilization of these low-cost prognostic biomarkers. [Table: see text]

Geographic variation in systemic therapy in men age 66 years and older with de novo metastatic castration-sensitive prostate cancer: A population-based study in a single payer health-system

50

Background: Significant developments in the standard of care for patients with de novo metastatic castration-sensitive prostate cancer (mCSPC) have been reported over the past decade. Treatment intensification with systemic therapies in addition to androgen deprivation therapy (ADT) alone is guideline recommended for most patients. We studied the geographic variation in the use of systemic therapy for de novo mCSPC in Ontario, Canada, a single-payer health system. Methods: We performed a population-based study of men aged 66 years and older diagnosed with de novo mCSPC between 2014-2019. We linked population-based healthcare databases, as administered at the level of Local Health Integration Networks (LHINs) in Ontario, to examine treatment patterns following diagnosis of de novo mCSPC. We categorized initial mCSPC treatments as those begun within 60 days preceding and 6 months following diagnosis and examined the proportion of patients receiving LHRH alone, first generation anti-androgen (AA) alone, combined androgen blockade (CAB; LHRH + 1st gen AA), ADT + abiraterone acetate + prednisone (AAP), and, ADT + docetaxel (D). In aggregate, we considered LHRH alone, AA alone and CAB as “standard ADT”, and ADT + AAP and ADT + D as “ADT-plus”. Multinomial logistic regression analyses were used to examine the association between receiving systemic treatment intensification (“ADT-plus”) or no prostate cancer pharmacotherapy relative to ADT across geographic regions, while adjusting for baseline patient and disease characteristics. Results: We identified 3,556 men over 66 with de novo mCSPC. Overall, 2794 (78.6%) received standard ADT, 311 (8.7%) did not receive prostate cancer-directed pharmacotherapy, and 451 patients (12.7%) of patients received “ADT-plus”. Utilization of AAP increased from 0.5% to 3% following the LATITUDE data release in 2017, while D decreased from 12% to 10%. There was significant variation in treatment strategies between geographic regions in use of “ADT-plus” ranging from 7 to 20% (p < 0.0001), a difference which persisted after accounting for patient demographics, comorbidity, rurality, and disease characteristics (p = 0.036). Conclusions: Despite proven survival benefits in randomized controlled trials, intensified treatment with docetaxel or abiraterone in addition to ADT was infrequently utilized in this population-based study of men age 66 years and over with mCSPC.

Real-world utilization of docetaxel among men with de novo metastatic castration-sensitive prostate cancer: A population-based study in men aged 66 or older

47

Background: Docetaxel was the first agent, when added to androgen deprivation therapy (ADT), to demonstrate a survival benefit in men with metastatic castration-sensitive prostate cancer (mCSPC). It remains an important guideline recommendation approach in these men. However, real-world experience among patients with de novo metastatic disease is poorly understood. Using population-based data from Ontario Canada, we examined the real-world experience of using docetaxel in mCSPC. Methods: Men aged 66 years and older diagnosed with de novo metastatic prostate cancer between 2014-2019 were captured. The Cancer Activity Level Reporting system tracks information regarding the use of cancer treatments, including details of systemic therapy. We identified patients who received docetaxel intensification to ADT following diagnosis of de novo mCSPC and analyzed the proportion of patients who completed 6 cycles of treatment, required a dose decrease, and who visited the emergency department (ED) or were hospitalized for febrile neutropenia. Results: Over the 5-year study period, 399 men received docetaxel treatment among 3,556 identified with de novo mCSPC. The median age was 72 (IQR 68-76) and mean Charlson comorbidity index was 0.15 (SD +/- 0.72). Of the 399 men, 230 (58%), 202 (51%) and 175 (44%) patients completed at least 4, 5 and 6 cycles of docetaxel, respectively. Dose reduction during docetaxel treatment was required in 173 (43%) patients. Filgrastim was prescribed among 29 (7.3%) patients. Hospitalization or ED visit for febrile neutropenia was observed in 63 (16 %) of patients who received docetaxel. Conclusions: Among men age 66 years and over who received docetaxel and ADT for mCSPC, less than half were able to complete all six prescribed cycles. In addition, over two fifth required dose reductions and 16% experienced febrile neutropenia requiring hospitalization or ED visit. These data highlight the differences in expected outcomes between clinical trial populations (as reported in CHAARTED) and routine use.

Prognostic impact of paraneoplastic syndromes on patients with non-metastatic renal cell carcinoma undergoing surgery: Results from Canadian Kidney Cancer information system

INTRODUCTION

The impact of paraneoplastic syndromes (PNS) on survival in patients with renal cell carcinoma (RCC) is uncertain. This study was conducted to analyze the association of PNS with recurrence and survival of patients with non-metastatic RCC undergoing nephrectomy.

METHODS

The Canadian Kidney Cancer information system is a multi-institutional cohort of patients started in January 2011. Patients with nephrectomy for non-metastatic RCC were identified. PNS included anemia, polycythemia, hypercalcemia, and weight loss. Associations between PNS and recurrence or death were assessed using Kaplan-Meier curves and multivariable analysis.

RESULTS

Of 4337 patients, 1314 (30.3%) had evidence of one or more PNS. Patients with PNS were older, had higher comorbidity, and had more advanced clinical and pathological tumor characteristics as compared to patients without PNS (all p<0.05). Kaplan-Meier five-year estimated recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were significantly worse in patients with PNS (63.7%, 84.3%, and 79.6%, respectively, for patients with PNS vs. 73.9%, 90.8%, and 90.1%, respectively, for patients without PNS, all p<0.005). On univariable analysis, presence of PNS increased risk of recurrence (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.48-1.90, p<0.0001) and cancer-related death (HR 1.85, 95% CI 1.34-2.54, p=0.0002). Adjusting for known prognostic factors, PNS was not associated with recurrence or survival.

CONCLUSIONS

In non-metastatic RCC patients undergoing surgery, presence of PNS is associated with older age, higher Charlson comorbidity index score, advanced tumor stage, and aggressive tumor histology. Following surgery, baseline PNS is not strongly independently associated with recurrence or death.

Current Management of Localized Muscle-Invasive Bladder Cancer: A Consensus Guideline from the Genitourinary Medical Oncologists of Canada

BACKGROUND: Despite recent advances in the management of muscle-invasive bladder cancer (MIBC), treatment outcomes remain suboptimal, and variability exists across current practice patterns. OBJECTIVE: To promote standardization of care for MIBC in Canada by developing a consensus guidelines using a multidisciplinary, evidence-based, patient-centered approach who specialize in bladder cancer. METHODS: A comprehensive literature search of PubMed, Medline, and Embase was performed; and most recent guidelines from national and international organizations were reviewed. Recommendations were made based on best available evidence, and strength of recommendations were graded based on quality of the evidence. RESULTS: Overall, 17 recommendations were made covering a broad range of topics including pathology review, staging investigations, systemic therapy, local definitive therapy and surveillance. Of these, 10 (59% ) were level 1 or 2, 7 (41% ) were level 3 or 4 recommendations. There were 2 recommendations which did not reach full consensus, and were based on majority opinion. This guideline also provides guidance for the management of cisplatin-ineligible patients, variant histologies, and bladder-sparing trimodality therapy. Potential biomarkers, ongoing clinical trials, and future directions are highlighted. CONCLUSIONS: This guideline embodies the collaborative expertise from all disciplines involved, and provides guidance to further optimize and standardize the management of MIBC.