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.

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.

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.

Outcomes for International Metastatic Renal Cell Carcinoma Database Consortium Prognostic Groups in Contemporary First-line Combination Therapies for Metastatic Renal Cell Carcinoma

BACKGROUND

The combination of immuno-oncology (IO) agents ipilimumab and nivolumab (IPI-NIVO) and vascular endothelial growth factor targeted therapies (VEGF-TT) combined with IO (IO-VEGF) are current standard of care first-line treatments for metastatic renal cell carcinoma (mRCC).

OBJECTIVE

To establish real-world clinical benchmarks for IO combination therapies based on the International mRCC Database Consortium (IMDC) criteria.

DESIGN, SETTING, AND PARTICIPANTS

Patients with mRCC who received first-line IPI-NIVO, IO-VEGF, or VEGF-TT from 2002 to 2021 were identified using the IMDC database and stratified according to IMDC risk groups.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Overall survival (OS), time to next treatment (TTNT), and treatment duration (TD) were calculated using the Kaplan-Meier method and compared between IMDC risk groups within each treatment cohort by the log-rank test. The overall response rate (ORR) was calculated by physician assessment of the best overall response. The primary outcome was OS at 18 mo.

RESULTS AND LIMITATIONS

In total, 728 patients received IPI-NIVO, 282 IO-VEGF, and 7163 VEGF-TT. The median follow-up times for patients remaining alive were 14.3 mo for IPI-NIVO, 14.9 mo IO-VEGF, and 34.4 mo for VEGF-TT. OS at 18 mo for favorable, intermediate, and poor risk was, respectively, 90%, 78%, and 50% for those receiving IPI-NIVO; 93%, 83%, and 74% for IO-VEGF; and 84%, 64%, and 28% for VEGF-TT. ORRs in favorable-, intermediate-, and poor-risk groups were 41.3%, 40.6%, and 33.0% for those receiving IPI-NIVO; 60.3%, 56.8%, and 40.9% for IO-VEGF; and 39.3%, 33.5%, and 20.9% for VEGF-TT, respectively. The IMDC model stratified patients into statistically distinct risk groups for the three endpoints of OS, TTNT, and TD within each treatment cohort. Limitations of this study were the retrospective design and short follow-up.

CONCLUSIONS

This study demonstrated that the IMDC model continues to risk stratify patients with mRCC treated with contemporary first-line IO combination therapies and provided real-world survival benchmarks.

PATIENT SUMMARY

The International Metastatic Renal Cell Carcinoma Database Consortium model continues to stratify patients with metastatic renal cell carcinoma receiving modern combination treatments in the real-world setting.

Fecal microbiota transplantation followed by anti–PD-1 treatment in patients with advanced melanoma

9533

Background: The gut microbiome has been shown to be a biomarker of response in patients (pts) with melanoma. Strategies to modify the microbiome are currently being investigated. We report the effects of Fecal Microbiota Transplantation (FMT) on safety and anti-PD-1 response in pts with melanoma from a phase I trial (NCT03772899). Methods: 20 pts with advanced melanoma with RECIST-evaluable disease, without prior anti-PD-1 treatment for advanced disease, were recruited from 3 Canadian academic centers. Pts with ECOG > 2, autoimmune diseases, immunosuppression or unstable brain metastases were excluded. Pts received 80-100 g of healthy donor stool via oral capsules and were treated with anti-PD-1 one week later. The primary objective was safety of combining FMT with anti-PD-1 therapy. Objective response rate (ORR) by RECIST 1.1 and correlative studies were secondary objectives. Flow cytometry and multiplex ELISA were performed on pts blood samples. Avatar mice were transplanted with stool samples obtained from participants on the trial before and after FMT. Mice were subsequently implanted with B-16 or MCA-205 tumors and received anti-PD-1 antibodies. Results: Median age was 75.5 years, 12 (60%) were male, 18 (90%) had stage 4 disease, and 5 (25%) pts harbored a BRAF mutation. Median follow-up was 11.2 months. FMT-related adverse events included grade 2 diarrhea (2 pts) and hypophosphatemia (1 pt), and 13 pts (65%) experienced grade 1 gastrointestinal toxicities. Grade 3 immune-related adverse events (irAE) were one each of myocarditis, nephritis, and fatigue. Anti-PD-1 therapy was discontinued for toxicity in 2 (10%) pts. No unexpected irAE or death on treatment occurred. ORR was 65% (13/20), of which 3 were CR. Clinical benefit rate (includes SD lasting > 6 months) was 75% (15/20). Median PFS was not reached, and one pt died from their disease. Translational analyses demonstrated upregulation of IL-17 post-FMT in responders, which correlated with upregulation of the frequency of Th17 cells in peripheral blood. In parallel, murine experiments showed that feces from pts pre-FMT did not sensitize tumors to anti-PD-1. In both tumor models, only feces obtained post-FMT from responders restored anti-PD-1 efficacy in mice, providing strong support that FMT contributed to the anti-tumor response observed in pts. Conclusions: FMT followed by anti-PD-1 treatment in melanoma pts undergoing therapy is safe and may lead to improved anti-tumor responses that can be reproduced in tumor mouse models. The gut microbiome plays an important role in responses to anti-PD-1 in patients with advanced melanoma, paving the way for future microbiome-based interventions. Clinical trial information: NCT03772899.

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.

Preventing adverse events in patients with renal cell carcinoma treated with doublet immunotherapy using fecal microbiota transplantation (FMT): Initial results from perform a phase I study

4553

Background: The treatment landscape of metastatic renal cell carcinoma (mRCC) has evolved with the advent of either dual immune checkpoint inhibition (ICI) or in combination with Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitor. Gut microbiota plays a central role in developing local and systemic immunity, with potential influence in controlling anti-tumor immune response in cancer patients treated with ICI. We hypothesize that FMT from healthy donors given before immunotherapy will establish a more resilient gut microbiota, reducing the treatment toxicity and improving response to therapy. PERFORM is an ongoing phase I study evaluating the safety of FMT and immunotherapy combination in first-line (1L) mRCC, and assessing whether FMT will prevent or mitigate immune-related adverse events (irAE). Methods: Eligible patients with untreated mRCC received a full dose and 2 supportive FMT procedures prior to the first 3 cycles of doublet ICI or in combination with VEGF-TKI. Primary endpoint is the feasibility and safety of combining FMT using intestinal bacteria existing in the stool of healthy donors with immunotherapy. Secondary endpoints include incidence of irAEs, objective response rate (ORR; RECIST v1.1), and changes in pts microbiome and immune profile post-FMT. We included a preliminary analysis of the first 10 patients. Results: 10 patients received FMT and doublet ICI therapy (10 ongoing). 8/10 (80%) patients were male. Median Age: 59.5 (53-71) years-old. Most common histology was clear cell RCC (90%) and all patients had an intermediate or poor-risk disease. 93.3% of planned FMT were administered. No dose-limiting toxicities due to FMT were observed. Median (range) follow-up was 5.5 (1–22) months. 4 patients (40%) discontinued treatment due to irAEs: colitis (n = 3), arthritis (n = 1). IrAEs were reported in 8 (80%) patients, including diarrhea (n = 6; 60%) and skin rash (n = 2, 20%). Grade 3/4 AEs were experienced by 6 (60%) patients, including colitis (n = 4, 40%). ORR was confirmed in 4/9 patients (44%; 95% CI, 30–60); 1 (11%) partial response. Microbiota and immune analysis data to be presented. Conclusions: The role of microbiome modification in preventing immune-related toxicities by adding FMT to ICI therapy was associated with a safety profile in unselected 1L mRCC and promising clinical efficacy data. Further prospective studies to examine the changes in the immune and microbiota profiles to determine biomarkers related to healthy outcomes/less frequent toxicities in patients receiving immunotherapy are warranted. Clinical trial information: NCT04163289.

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]

Impact of systemic therapy sequencing on overall survival for patients with advanced BRAF-mutated melanoma

9552

Background: Both immune checkpoint inhibitors (ICI) and BRAF targeted therapy (TT) are effective treatments for patients with advanced BRAF-mutated melanoma. However, the choice of first-line (1L) therapy is at the discretion of treating oncologists without clear guidance from current available data or established guidelines. Utilizing prospectively collected data from the Canadian Melanoma Research Network (CMRN) database, we provide real-world evidence to highlight the impact of sequencing these therapies. Methods: Prospective data from 9 cancer centres in Canada was retrieved from the CMRN database for patients with unresectable/metastatic melanoma, with BRAF targetable subtypes, who received at least one-cycle of 1L palliative-intent ICI or TT, and at least 1-year of follow-up. We categorized patients into 2 groups: 1L BRAF±MEK inhibitors with/without subsequent PD-1±CTLA-4 inhibitors (1L-TT), or vice versa (1L-ICI). The primary study outcome was overall survival (OS). Survival outcomes were analyzed through Kaplan-Meier methods, and multivariable Cox analysis was utilized to account for potential confounders. Results: Our study (N=235) included 152 and 83 patients in 1L-TT and 1L-ICI groups, respectively. Combined BRAF-MEK inhibitors accounted for 59% of the 1L-TT group, whereas single-agent IO accounted for 66% of the 1L-ICI group. There were 93 patients who received second-line (2L) therapy, with a non-significant trend of 1L-TT group receiving more 2L therapy compared to 1L-ICI group (65% vs. 43%, P=0.404). Neither treatment group showed significant differences in median time on 1L therapy (P=0.645) or 2L therapy (P=0.686). The 1L-ICI group was associated with a favourable median overall survival (OS) compared to 1L-TT group (19.3 vs. 10.0 months, P=0.031). Specifically, the ICI only group had the highest median OS, followed by TT-ICI sequence, ICI-TT sequence, and TT only groups respectively (not reached vs. 38.3 vs. 16.9 vs. 6.1 months, P<0.001). However, this OS benefit (HR 0.89, 95% 0.51-1.53, P=0.644) was non-significant upon controlling for confounders such as baseline metastatic sites >2 (HR 2.07, 95%CI 1.24-3.46, P=0.006) and ECOG ≥2 (HR 3.47, 95%CI 2.02-5.97, P<0.001) in multivariable Cox analysis. Conclusions: There was no significant difference in OS between 1L-TT and 1L-IO groups. Rather, OS is driven mostly by the patient’s clinical status and tumour-associated features. Our study provides real-world evidence in an understudied area. Further studies are needed to validate our findings to inform guideline development.[Table: see text]

Outcomes of first-line (1L) ipilimumab and nivolumab (IPI-NIVO) and subsequent therapy in metastatic renal cell carcinoma (mRCC): Results from the International mRCC Database Consortium (IMDC)

4554

Background: IPI NIVO is approved for 1L treatment of IMDC intermediate/poor risk mRCC based on the CHECKMATE 214 trial. Herein, we report the clinical effectiveness of 1L IPI NIVO and second line (2L) therapy in the real-world setting. Methods: Using the IMDC dataset, patients (pts) treated with 1L IPI NIVO were identified. The outcomes of interest were 1L and 2L overall response rate (ORR), treatment duration (TD), time to next treatment (TTNT), and overall survival (OS). Results: 706 pts were included: 9% (57/614), 58% (354/614), and 33% (203/614) were IMDC favorable (fav), intermediate (int), and poor risk, respectively. Median age was 61 years. The majority of pts were males (71%), had clear cell histology (85%), and underwent nephrectomy (61%). 36%, 19%, and 8% of patients had bone, liver, and brain metastases, respectively. The 12-month OS for pts with IMDC fav, int, and poor risk disease was 92%, 79%, and 56%, respectively (p<0.01). The corresponding estimates for 24 months were 80%, 69%, and 38% (p<0.01). Pts who responded (39%) were more likely to have better IMDC risk category (p=0.02), received nephrectomy (p=0.04), normal neutrophil count (p<0.01), and clear cell histology (p=0.01). Pts with progressive disease as best response (27%) were more likely to have not received nephrectomy (p<0.01), worse IMDC risk category (p=0.02), bone metastases (p=0.01), liver metastases (p=0.04), and non-clear cell histology (p=0.01). Of the 66% (466/706) of pts who discontinued 1L IPI NIVO, 51% (236/466) received 2L therapy: sunitinib (40%), cabozantinib (25%), pazopanib (18%), axitinib (8%), and others (9%). The ORR, median TD, and median OS for those who received either sunitinib, cabozantinib, pazopanib or axitinib was 16%, 4.5 months (mo) (95% CI 3.7-5.6), and 14.5 mo (95% CI 10.9-25.9), respectively. 33% (129/386) of pts discontinued IPI NIVO due to irAEs. Conclusions: Our study benchmarks the real-world experience of 1L IPI NIVO in mRCC. IMDC criteria is prognostic for clinical outcome. Tyrosine kinase inhibitors have clinical activity post IPI NIVO.[Table: see text]

Efficacy of immune-checkpoint inhibitors (ICI) in the treatment of older adults with metastatic renal cell carcinoma (mRCC) - an International mRCC Database Consortium (IMDC) analysis

OBJECTIVE

Older adults with metastatic renal cell carcinoma(mRCC) are underrepresented in immune-checkpoint inhibitor(ICI) registration trials. Here we compare the efficacy of ICI treatments in older vs. younger adults with mRCC.

METHODS

Using the International mRCC Database Consortium(IMDC), patients treated with a PD(L)-1 based ICI were identified. Older adult was defined as ≥70-years at the time of treatment. Descriptive statistics were summarized in means, medians, and proportions. Effectiveness endpoints included overall survival (OS), time-to-treatment failure(TTF), time-to-next treatment(TNT), and overall response rate(ORR). Hazards ratios were adjusted(aHR) for IMDC risk factors, histology, line of treatment and older age.

RESULTS

Of 1427 included patients, 397(28%) were older adults. ICI was used as 1st line(1 L) in 40%, 2nd line(2 L) in 49% and 3rd line(3 L) in 11% of patients. In univariable analysis, older adults had inferior OS compared to younger adults(25.1 m vs. 30.8 m, p < 0.01). There were no significant differences in TTF (6.9 m vs. 6.9 m, p = 0.4) or TNT(9.1 m vs 10 m, p = 0.3) between groups. In multivariable analyses, older age was not independently associated with worse OS(aHR = 1.02, p = 0.8), TTF(aHR = 0.95, p = 0.6) or TNT(aHR = 0.93, p = 0.5). Older adults had a lower ORR compared to younger adults(24% vs. 31%, p = 0.01), which was mainly driven by responses in 1 L(31% vs. 44%, p = 0.02) and not observed in 2 L/3 L.

CONCLUSIONS

After multivariable analyses, older adults with mRCC treated with ICI had no difference in OS, TTF or TNT when compared to younger adults. Our data support that chronological older age should not preclude patients from receiving ICI based therapies.

Multidisciplinary management of locally advanced and metastatic cutaneous squamous cell carcinoma

Non-melanoma skin cancers are the most prevalent form of cancer, with cutaneous squamous cell carcinoma (cscc) being the 2nd most common type. Patients presenting with high-risk lesions associated with locally advanced or metastatic cscc face high rates of recurrence and mortality. Accurate staging and risk stratification for patients can be challenging because no system is universally accepted, and no Canadian guidelines currently exist. Patients with advanced cscc are often deemed ineligible for either or both of curative surgery and radiation therapy (rt) and, until recently, were limited to off-label systemic cisplatin-fluorouracil or cetuximab therapy, which offers modest clinical benefits and potentially severe toxicity. A new systemic therapy, cemiplimab, has been approved for the treatment of locally advanced and metastatic cscc. In the present review, we provide recommendations for patient classification and staging based on current guidelines, direction for determining patient eligibility for surgery and rt, and an overview of the available systemic treatment options for advanced cscc and of the benefits of a multidisciplinary approach to patient management.

Efficacy of immune-checkpoint inhibitors (ICI) in the treatment of older adults with metastatic renal cell carcinoma (mRCC): An international mRCC database consortium (IMDC) analysis

5068

Background: Anti-PD-1/PD-L1 immune-checkpoint inhibitors (ICI) are now a standard of care in metastatic renal cell carcinoma (mRCC). Older adults were underrepresented in registration trials and given that immunological senescence may affect the anti-tumor activity of ICIs, there is uncertainty about the efficacy of ICIs in this population. Here we provide real world data on outcomes of older adults with mRCC treated with ICIs. Methods: Patients with mRCC treated with a PD-1/PD-L1 ICI either as monotherapy or as a combination treatment from 2000 to 2019 were included. Older adult was defined as ≥ 70-years at the time of ICI treatment. Descriptive statistics were summarized in means, medians and proportions. Efficacy was assessed by survival analysis, including overall survival (OS), time to treatment failure (TTF), and overall response rate (ORR). Multivariate analyses adjusted for imbalances in IMDC risk factors. P < 0.05 was considered statistically significant. Results: Of 1427 patients, 397 (28%) were older adults. Mean age of older vs. younger adults was 74 (70-92) vs. 60 (22-69) years. Groups were comparable in terms of gender (Female 28.5% vs. 26.1%, p = 0.36), rates of nephrectomy (21% vs. 18.3%, p = 0.24) and presence of sarcomatoid features (12.3% vs. 17.8%, p = 0.14). Proportion of IMDC risk-groups between older vs. younger adults were as follows: 15.4% vs. 18.2% for favorable, 61.2% vs. 59.1% for intermediate, and 23.4% vs. 22.7% for poor; there was no statistical difference (p = 0.55). ICI was used as 1st line in 40%, 2nd line in 48.5% and 3rd line in 11.5% patients; older adults were less likely to be treated with ICI in 1st line (32.2% vs. 43%, p < 0.01). In terms of survival, older adults had poorer median OS (25.1m vs. 30.8m, p < 0.01) but similar median TTF (6.9m vs. 6.9m, p = 0.40) compared to younger adults. In multivariate analyses, older age was not a predictor of either worse OS (aHR = 1.02, p = 0.86) or TTF (aHR = 0.95, p = 0.59). Older adults had a lower ORR compared to younger (24% vs. 31%, p = 0.01), which was mainly driven by responses in 1st line (31% vs. 44%, p = 0.02) and not observed in 2nd/3rd line (20% vs. 20%, p = 0.86). Conclusions: On multivariate analyses, older adults with mRCC treated with ICI had no difference in OS and TTF when compared to younger adults, despite having lower ORR in 1st line. Our data supports that older age is not an independent risk factor for survival; thus, treatment selection should not be based solely on chronological age.

Deferred Cytoreductive Nephrectomy in Patients with Newly Diagnosed Metastatic Renal Cell Carcinoma

BACKGROUND

The use of cytoreductive nephrectomy (CN) selectively for patients who show a favorable response to upfront systemic therapy may be an approach to select optimal candidates with metastatic renal cell carcinoma (mRCC) who are most likely to benefit.

OBJECTIVE

We sought to characterize outcomes of deferred CN (dCN) after upfront sunitinib, outcomes relative to sunitinib alone, and outcomes of CN followed by sunitinib.

DESIGN, SETTING, AND PARTICIPANTS

We used the prospectively maintained International mRCC Database Consortium (IMDC) database to identify patients with newly diagnosed mRCC (2006-2018).

INTERVENTION

Sunitinib alone, upfront CN followed by sunitinib, sunitinib followed by dCN.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Outcomes were overall survival (OS) and time to sunitinib treatment failure (TTF). Kaplan-Meier and multivariable Cox regression analyses were performed; dCN was analyzed as a time-varying covariate to account for immortal time bias.

RESULTS AND LIMITATIONS

We evaluated 1541 patients, of whom 651 (42%) received sunitinib alone, 805 (52%) underwent CN followed by sunitinib, and 85 (5.5%) received sunitinib followed by dCN, at a median of 7.8 mo from diagnosis. Median OS periods for patients treated with sunitinib alone, CN followed by sunitinib, and sunitinib followed by dCN were 10, 19, and 46 mo, respectively, while the median TTF values were 4, 8, and 13 mo, respectively. In multivariable regression analyses, sunitinib followed by dCN was significantly associated with improved OS (hazard ratio [HR] = 0.45, 95% confidence interval [CI] 0.33-0.60, p < 0.001) and TTF (HR = 0.62, 95% CI 0.46-0.85, p = 0.003) versus sunitinib alone. Among CN-treated patients, sunitinib followed by dCN was associated with improved OS (HR = 0.52, 95% CI 0.39-0.70, p < 0.001) and TTF (HR = 0.71, 95% CI 0.56-0.90, p = 0.005) compared with upfront CN followed by sunitinib. In various sensitivity analyses, dCN remained significantly associated with improved OS and TTF.

CONCLUSIONS

Patients who received dCN were carefully selected and achieved long OS. With these benchmark outcomes, optimal selection criteria need to be identified and confirmation of the role of dCN in a clinical trial is warranted.

PATIENT SUMMARY

We characterized benchmark survival outcomes for patients with metastatic kidney cancer treated with sunitinib alone, nephrectomy (kidney removal) followed by sunitinib, and sunitinib followed by nephrectomy. Patients who had their nephrectomy after an initial course of sunitinib had prolonged survival.

High-dose chemotherapy with autologous stem cell transplantation (HDC-ASCT) for relapsed metastatic germ cell tumors (mGCTs): The Alberta experience from 2001 to 2018

406

Background: HDC-ASCT is a standard therapy for patients (pts) with mGCTs whose disease progresses on or after conventional dose chemotherapy. We conducted a retrospective review of HDC-ASCT in pts with relapsed mCGT in Alberta over the past two decades. Methods: Pts with mGCTs who received HDC-ASCT at two provincial referral cancer centers in Alberta, Canada from 2001-2018 were identified. 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 pts were identified. Median age was 28 years (range 19 – 56). Majority (95%) had non-seminoma histology and testis/retroperitoneal primary (84%). Twenty pts (47%) had poor risk disease as per IGCCC at start of first-line chemotherapy. HDC-ASCT was used as second-line therapy in 65% and 58% received tandem HDC-ASCT. Median follow-up from ASCT was 22 months (range 2 – 181). At last follow-up, 42% of pts are alive without disease, including 3/7 (43%) of pts with primary mediastinal disease. Two-year and 5-year DFS/OS were 44%/51% and 41%/43%, respectively. Median OS and DFS for all pts were 27.9 months (10.2 – NR) and 9.3 months (4.2 – 124), respectively. Conclusions: We found that HDC-ASCT is an effective salvage therapy in mGCT, consistent with existing literature. Pts appeared to benefit regardless of primary site. Though limited by small sample size, we found a numerical difference in DFS and OS between 2nd and 3rd line HDC-ASCT and single vs. tandem ASCT.[Table: see text]

Deferred cytoreductive nephrectomy among patients with newly diagnosed metastatic renal cell carcinoma treated initially with sunitinib

4578

Background: While the CARMENA trial prompts more caution with upfront cytoreductive nephrectomy (CN) in patients with metastatic renal cell carcinoma (mRCC), 17% of patients in the sunitinib alone arm underwent deferred CN (dCN). Upfront systemic therapy has been proposed as a potential litmus test to identify patients suitable for CN, but data on outcomes are limited. We sought to characterize outcomes of dCN after upfront sunitinib relative to sunitinib alone. Methods: Patients with newly diagnosed mRCC receiving upfront sunitinib were identified from the International mRCC Database Consortium (IMDC) from 2006-2018. All CNs done after initial sunitinib were included, excluding CNs performed after sunitinib failure. The outcomes were overall survival (OS) and time to treatment failure (TTF). Kaplan Meier and multivariable Cox regression analyses were performed; dCN was analyzed as a time-varying covariate to account for immortal time bias. Results: The cohort included 708 patients of whom 53 (7.5%) underwent dCN at a median of 6.5 months (IQR 3.5,10.5) from diagnosis. Patients in the dCN group were more likely to have better Karnofsky performance status (KPS), intermediate IMDC risk, fewer metastatic sites, and response to upfront sunitinib (Table). There were 604 deaths during a median follow-up of 63 months. Median OS and TTF with dCN were 43.5 and 19.8 months vs. 9.4 and 4.3 months without, respectively. Upon multivariable analysis, dCN remained significantly associated with OS (HR 0.45, 95%CI 0.31-0.65; p < 0.001) but not TTF (HR 0.73, 95%CI 0.52-1.01; p = 0.056). Conclusions: Patients who received dCN were carefully selected and achieved long OS. With these benchmark outcomes, optimal selection criteria need to be identified and confirmation of the role of dCN in a clinical trial is warranted. [Table: see text]

A randomized trial comparing four-weekly versus 12-weekly administration of bone-targeted agents (denosumab, zoledronate, or pamidronate) in patients with bone metastases from either breast or castration-resistant prostate cancer

11501

Background: Defining the optimal dosing interval of commonly used bone-targeted agents (BTAs), such as denosumab and bisphosphonates, for patients with bone metastases remains an important clinical question. We performed a pragmatic randomised trial comparing the non-inferiority of 12- versus 4-weekly BTAs in patients with bone metastases from breast and prostate cancer. Methods: Patients with bone metastases, who were either BTA-naïve, or already receiving, denosumab, pamidronate or zoledronate were eligible. They were randomised to receive their chosen BTA every 12- or 4-weeks for one year. The primary endpoint was Health related quality of life (HRQL) (EORTC-QLQ-C30 Functional Domain - Physical Subdomain). Secondary endpoints included: pain (EORTC-QLQ-BM22 - pain domain), Global Health Status (EORTC-QLQ-C30), symptomatic skeletal events (SSE) rates and time to SSEs. Adverse events and toxicity profiles were also compared. Results: Of 263 patients (60.8% breast and 39.2% prostate), 130 (49.4%) were randomised to 12-weekly and 133 (50.6%) to 4-weekly therapy. 138 (52.5%) were bone-agent naïve. The BTAs included; denosumab (n=148, 56.3%), zoledronate (n=63, 24.0%) and pamidronate (n=52, 19.8%). Study-reported outcomes showed no significant difference in; HRQL-physical domain (median [range]: 0 [-86, 40] vs. 0 [-66, 53.3]), pain (median [range]: 0 [-66, 72] vs. 0 [-100, 88]), Global Health Status (median [range]: 0 [-100, 66.7] vs. 0 [-83, 33.3]), SSE rates (N [%]: 24 [18.5%] vs. 22 [16.5%]), 1-year SSE-free rate (median, range; 73.2% [63.6, 80.7] vs. 77.9% [69.1, 84.4]) between the 12- and 4-weekly arms, respectively. Subgroup analyses for BTA naïve and pre-treated patients, and for patients receiving denosumab, zoledronate and pamidronate, showed no significant difference between the 12- and 4-weekly arms. There was no significant difference in reported rates of renal impairment (2.3% vs. 3.0%), symptomatic hypocalcaemia (1.5% vs. 1.5%) or osteonecrosis of the jaw (0.8% vs. 0.8%). Conclusion: The findings of this trial are consistent with those previously reported for de-escalating zoledronate. This trial also included patients receiving de-escalated denosumab and pamidronate. While the results of the Swiss REDUSE trial are awaited, the data presented would suggest that de-escalation of all commonly used BTAs is a reasonable treatment option. Clinical trial information: NCT02721433.

Cytoreductive Nephrectomy in Metastatic Papillary Renal Cell Carcinoma: Results from the International Metastatic Renal Cell Carcinoma Database Consortium

BACKGROUND

There is evidence that cytoreductive nephrectomy (CN) may be beneficial in metastatic renal cell carcinoma (mRCC). This has been studied predominantly in clear-cell RCC, with more limited data on the role of CN in patients with papillary histology.

OBJECTIVE

To determine the benefit of CN in synchronous metastatic papillary RCC.

DESIGN, SETTING, AND PARTICIPANTS

Using the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) database, a retrospective analysis was performed for patients with papillary mRCC treated with or without CN.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Median overall survival (OS) and progression-free survival (PFS) were determined for both patient groups. Cox regression analysis was performed to control for imbalances in individual IMDC risk factors.

RESULTS AND LIMITATIONS

In total, 647 patients with papillary mRCC were identified, of whom 353 had synchronous metastatic disease. Of these, 109 patients were treated with CN and 244 were not. The median follow-up was 57.1mo (95% confidence interval [CI] 32.9-77.8) and the OS from the start of first-line targeted therapy for the entire cohort was 13.2mo (95% CI 12.0-16.1). Median OS for patients with CN was 16.3mo, compared to 8.6mo (p<0.0001) in the no-CN group. When adjusted for individual IMDC risk factors, the hazard ratio (HR) of death for CN was 0.62 (95% CI 0.45-0.85; p=0.0031). Limitations include the retrospective nature of the analysis.

CONCLUSIONS

The use of CN in patients with mRCC and papillary histology appears to be associated with better survival compared to no CN after adjustment for risk criteria. Selection of appropriate candidates for CN is crucial. A clinical trial in this rare population may not be possible.

PATIENT SUMMARY

In a population of patients with advanced papillary kidney cancer, we found that surgical removal of the primary kidney tumor was associated with better overall survival.

Real-world outcomes of nivolumab and cabozantinib in metastatic renal cell carcinoma: results from the International Metastatic Renal Cell Carcinoma Database Consortium

Objectives

In the present study, we explored the real-world efficacy of the immuno-oncology checkpoint inhibitor nivolumab and the tyrosine kinase inhibitor cabozantinib in the second-line setting.

Methods

Using the International Metastatic Renal Cell Carcinoma Database Consortium (imdc) dataset, a retrospective analysis of patients with metastatic renal cell carcinoma (mrcc) treated with nivolumab or cabozantinib in the second line after prior therapy targeted to the vascular endothelial growth factor receptor (vegfr) was performed. Baseline characteristics and imdc risk factors were collected. Overall survival (os) and time to treatment failure (ttf) were calculated using Kaplan-Meier curves. Overall response rates (orrs) were determined for each therapy. Multivariable Cox regression analysis was performed to determine survival differences between cabozantinib and nivolumab treatment.

Results

The analysis included 225 patients treated with nivolumab and 53 treated with cabozantinib. No significant difference in median os was observed: 22.10 months [95% confidence interval (ci): 17.18 months to not reached] with nivolumab and 23.70 months (95% ci: 15.52 months to not reached) with cabozantinib (p = 0.61). The ttf was also similar at 6.90 months (95% ci: 4.60 months to 9.20 months) with nivolumab and 7.39 months (95% ci: 5.52 months to 12.85 months) with cabozantinib (p = 0.20). The adjusted hazard ratio (hr) for nivolumab compared with cabozantinib was 1.30 (95% ci: 0.73 to 2.3), p = 0.38. When adjusted by imdc criteria and age, the hr was 1.32 (95% ci: 0.74 to 2.38), p = 0.35.

Conclusions

Real-world imdc data indicate comparable os and ttf for nivolumab and cabozantinib. Both agents are reasonable therapeutic options for patients progressing after initial first-line vegfr-targeted therapy.

Phase I Trials of Anti-ENPP3 Antibody-Drug Conjugates in Advanced Refractory Renal Cell Carcinomas

Purpose: To determine the safety, pharmacokinetics, and recommended phase II dose of an antibody-drug conjugate (ADC) targeting ectonucleotide phosphodiesterases-pyrophosphatase 3 (ENPP3) conjugated to monomethyl auristatin F (MMAF) in subjects with advanced metastatic renal cell carcinoma (mRCC).Patients and Methods: Two phase I studies were conducted sequentially with 2 ADCs considered equivalent, hybridoma-derived AGS-16M8F and Chinese hamster ovary-derived AGS-16C3F. AGS-16M8F was administered intravenously every 3 weeks at 5 dose levels ranging from 0.6 to 4.8 mg/kg until unacceptable toxicity or progression. The study was terminated before reaching the MTD. A second study with AGS-16C3F started with the AGS-16M8F bridging dose of 4.8 mg/kg given every 3 weeks.Results: The AGS-16M8F study (n = 26) closed before reaching the MTD. The median duration of treatment was 12 weeks (1.7-83 weeks). One subject had durable partial response (PR; 83 weeks) and 1 subject had prolonged stable disease (48 weeks). In the AGS-16C3F study (n = 34), the protocol-defined MTD was 3.6 mg/kg, but this was not tolerated in multiple doses. Reversible keratopathy was dose limiting and required multiple dose deescalations. The 1.8 mg/kg dose was determined to be safe and was associated with clinically relevant signs of antitumor response. Three of 13 subjects at 1.8 mg/kg had durable PRs (range, 100-143 weeks). Eight subjects at 2.7 mg/kg and 1.8 mg/kg had disease control >37 weeks (37.5-141 weeks).Conclusions: AGS-16C3F was tolerated and had durable antitumor activity at 1.8 mg/kg every 3 weeks. Clin Cancer Res; 24(18); 4399-406. ©2018 AACR.

Real world outcomes of nivolumab and cabozantinib in metastatic renal cell carcinoma: Results from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)

615

Background: The immuno-oncology (IO) checkpoint inhibitor nivolumab and the tyrosine kinase inhibitor (TKI) cabozantinib have both been shown in phase III clinical trials to be effective in metastatic renal cell carcinoma (mRCC) after progression on first-line therapy. We sought to explore the real-world efficacy of these therapies in second-line mRCC. Methods: Using the IMDC database, a retrospective analysis was performed on mRCC patients treated with second-line nivolumab or cabozantinib. Baseline characteristics and IMDC risk factors were collected. Overall survival (OS), time to treatment failure (TTF), and response rates were determined for each therapy. Multivariable Cox regression analysis was performed to determine survival differences. Results: 225 patients were treated with nivolumab and 53 with cabozantinib. There was no significant difference in OS identified, with a mOS for nivolumab of 22.1 months (95% CI 17.18 – NR) and 23.7 months (95% CI 15.52 vs. NR) for cabozantinib, p = 0.6053. The TTF was also similar, with 6.90 months (95% CI 4.60 – 9.20) for nivolumab versus 7.39 months (95% CI 5.52 – 12.85) for cabozantinib, p = 0.1983. The adjusted hazard ratio (HR) for nivolumab vs. cabozantinib was 1.297 (95% CI – 0.728 – 2.312), p = 0.3775. Conclusions: Nivolumab and cabozantinib appear to have similar efficacy in terms of OS and TTF in this real-world patient population, thus both novel agents are reasonable therapeutic options for patients progressing after initial first-line therapy. [Table: see text]

Influence of aggressive-variant prostate cancer (AVPC) features on outcome of metastatic hormone-sensitive prostate cancer (mHSPC) treated by chemohormonal therapy (CHT)

193

Background: Outcomes of patients (pts) undergoing CHT for mHSPC are heterogeneous, with some rapidly developing castration-resistance (CRPC). While AVPC ("anaplastic") features are described in CRPC, less is known in the mHSPC setting. In this multi-institutional cohort, we explored pre-treatment factors associated with poor outcome. Methods: De-novo mHSPC pts treated with CHT from June 2014 to July 2017 at The Ottawa Hospital Cancer Centre (TOHCC) and London Regional Cancer Centre (LRCC) were retrospectively identified. AVPC features (defined below) were collected and cumulatively scored (0, 1, or 2+), along with baseline, treatment and outcome data. Statistical comparisons utilized Cox regression analysis and Kaplan-Meier method for association with CRPC and survival. Results: 92 pts (58 TOHCC, 34 LRCC) met inclusion for study; 83 (90%) had "high-volume" disease (≥4 bone lesions; or ≥1 visceral metastasis), 69/73 (95%) prostate biopsies scored Gleason 8-10, and 55 (60%) had AVPC features: >5 cm nodal/pelvic mass (28), visceral metastases (21), lytic bone metastases (16), elevated LDH (12), low PSA (4), or neuroendocrine differentiation (2). Pre-docetaxel PSA fall of <50, 50-75, 75-90, and ≥90% baseline occurred in 12, 13, 19, and 56% respectively. Docetaxel was initiated a median of 66 days after androgen-deprivation, with 82% completing 5 or 6 cycles. 9 pts (10%) progressed during docetaxel, and 31 pts (34%) developed CRPC < 12 months. Median time to CRPC was 18.4, 14.0, and 11.0 months for 0, 1, and 2+ AVPC features (log rank p=0.009). CRPC was also associated with pre-docetaxel PSA fall <75% (p<0.001) and high alkaline phosphatase (p=0.016). At 18 months median follow-up, 16/55 (29%) with AVPC features have died versus 1/37 (3%) without (log rank p=0.001). In multivariable analysis, AVPC features and pre-docetaxel PSA fall were independently (p<0.05) associated with survival. Conclusions: In our study, mHSPC pts with AVPC features and suboptimal (<75%) pre-docetaxel PSA decline had poor prognosis. These features should be validated in larger cohorts to potentially identify mHSPC pts suitable for further study in clinical trials.

Cytoreductive nephrectomy in metastatic papillary renal cell carcinoma: Results from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)

581

Background: There is evidence that cytoreductive nephrectomy (CN) may be beneficial in metastatic renal cell carcinoma (mRCC), but the role of CN in patients with papillary histology is unclear. Methods: Using the IMDC database, a retrospective analysis was performed on patients with papillary mRCC treated with or without CN. Baseline characteristics and IMDC risk factors were collected. Median overall survival (OS) was determined for both patient groups. Multivariable Cox regression analysis was performed to control for imbalances in individual IMDC risk factors. Results: In total, 353 patients with papillary mRCC with (n = 75) or without (n = 278) a component of clear cell histology were identified. Median follow-up time was 57.1 months (95% CI 32.9-77.8) and the OS from the start of first-line targeted therapy for the entire cohort was 13.2 months (95% CI 12.0-16.1). Baseline characteristics are in Table 1 and patients who had CN were more likely to be younger, with better KPS, and have sarcomatoid histology. Median OS in patients with CN was 16.3 months (95% CI 13.1-19.2), compared to 8.6 months (95% CI 6.1-12.2; p < 0.0001) in the no CN group. When adjusted for individual IMDC risk factors, the hazard ratio (HR) of death for CN was 0.62 (95% CI 0.45-0.85; p = 0.0031). Conclusions: The use of CN in patients with mRCC and papillary histology appears to be associated with improved survival when compared to no CN after adjustment for risk criteria. A clinical trial in this rare population may not be possible but this data does corroborate with clear cell literature. [Table: see text]

Checkpoint inhibitors in metastatic renal cell carcinoma patients including elderly subgroups: Results from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)

4580

Background: Immuno-oncology (IO) checkpoint inhibitor treatment outcomes are poorly characterized in the real world metastatic renal cell cancer (mRCC) patient population, including geriatric patients. Methods: Using the IMDC database, a retrospective analysis was performed on mRCC patients treated with IO, as listed below. Patients received one or more lines of IO therapy, with or without a targeted agent. Duration of treatment (DOT) and overall response rates (ORR) were calculated. Cox regression analysis was performed to examine the association between age as a continuous variable and DOT. Results: 312 mRCC patients treated with IO were included. In patients who were evaluable, ORR to IO therapy was 29% (32% first-, 22% second-, 33% third-, and 32% fourth-line treatment (Tx)). Patients treated with second-line IO therapy were divided into favorable, intermediate, and poor risk using IMDC criteria; the corresponding median DOT rates were not reached (NR), 8.6 mo, and 1.9 mo, respectively (p<0.0001). Based upon age, hazard ratios were calculated in the first- through fourth-line therapy setting, ranging from 1.03 to 0.97. Conclusions: The ORR to IO appears to remain consistent, regardless of line of therapy. In the second-line, IMDC criteria appear to appropriately stratify patients into favorable, intermediate, and poor risk groups for DOT. Premature OS data will be updated. In contrast to clinical trial data, longer DOT is observed in real world practice. Age may not be a factor influencing DOT. [Table: see text]

Phase II study of individualized sunitinib (SUN) as first-line therapy for metastatic renal cell cancer

4514

Background: Higher SUN exposure is associated with better outcomes. Patients (pts) with minimum toxicity on the standard schedule do worse than pts needing dosing changes for toxicity. Methods: It was hypothesized that toxicity-driven dose/schedule individualization would improve the primary endpoint (PFS) from 8.5 (EFFECT trial) to 14 months (mo), with 99 pts required to detect this with 90% power and 2-sided alpha = 0.05. In a prospective phase II study (eligibility as EFFECT) pts start on 50 mg/day (d) for 28 d with treatment (Rx) breaks reduced to 7 d. If grade-2 toxicity develops before d 28, pts stay on a 50 mg on the next cycle with the number of d on Rx individualized aiming for ≤ grade-2 toxicity. Dose is reduced to 37.5 mg and then 25 mg if pts do not tolerate a 50 mg or 37.5 mg dose respectively for at least 7 d. Pts with minimum toxicity on d 28 are escalated to 62.5 mg and then 75 mg. Results: 117 pts were enrolled in 12 centers. Nine non-evaluable pts came off early due to toxicity (5), non-compliance (2) and global deterioration (2). Of 108 pts evaluable for response (IMDC favorable 31.5%, intermediate 58.3%, poor 10.2%. Bone mets 19%, Nephrect 83%), 10 are still on Rx. Dose was escalated in 20 pts (18.5%) to 62.5 mg (12 pts) and then to 75 mg (8 pts). In 49 pts (45.4%) eligible for dose reduction by standard criteria, a 50 mg dose was maintained but for 7 - 24 d, while 7 pts (6.5%) stayed on a 28 d schedule. Dose was reduced to 37.5 mg in 22 pts (20.4% vs. 36 - 63% in 4 large SUN trials) and to 25 mg in 10 pts (9.3% vs. 27 - 43% in 4 trials). Rx was stopped due to toxicity in 10/117 pts (9.3% vs. 15 - 19% in 4 trials). See table for response (ORR, 108 pts) and survival (117 pts) data vs. EFFECT (146 pts). The median followup is 15.5 mo (0.6 -37.9) for PFS and 24.5 mo (4.4 - 47.7) for OS. Conclusions: The null hypothesis of the PFS being 8.5 mo can be rejected with a p < 0.001. Individualized dosing is safe and feasible in a multicenter setting and associated with improved dose intensity and one of the best ORR, PFS and OS reported for a TKI. Clinical trial information: NCT01499121. [Table: see text]

Real world experience of immuno-oncology agents in metastatic renal cell carcinoma: Results from the IMDC

492

Background: Immuno-oncology (IO) checkpoint inhibitors have demonstrated efficacy in metastatic renal cell cancer (mRCC) treatment. Real world data is required to assess outcomes when applied to the general population. Methods: A retrospective analysis was performed using the IMDC database. It included mRCC patients treated with IO agents, including atezolizumab (Atezo), avelumab, ipilimumab, nivolumab (Nivo), and pembrolizumab (Pembro). Some patients were treated with combination therapy with a targeted agent. Patients may have received IO therapy as first-, second-, third-, or fourth-line treatment. Overall survival (OS), treatment duration, and overall response rates (ORR) were calculated. Results: 255 patients with mRCC treated with IO therapy were included. The ORR to IO therapy in those patients who were evaluable was 29% (32% first-, 22% second-, 33% third-, and 32% fourth-line therapy). Patients treated with second-line IO therapy were divided into favorable, intermediate, and poor risk using IMDC criteria; the corresponding median OS rates were not reached, 26.7 mo, and 12.1 mo, respectively (p<0.0001). Conclusions: Response rates to IO therapies appear to remain consistent no matter which line of therapy it is used in. Within second-line treatment, IMDC criteria appear to stratify patients appropriately into favorable, intermediate, and poor risk groups. Survival data are premature and will be updated. In contrast to Nivo clinical trial data, where median treatment duration was 5.5 mo, longer treatment length is observed in real world practice. [Table: see text]

Early docetaxel-resistance in metastatic hormone-sensitive prostate cancer

260

Background: The addition of docetaxel to standard androgen deprivation therapy (ADT) has been shown to improve the survival of men with metastatic hormone-sensitive prostate cancer (MHSPC) (Sweeney 2015, James 2016). We noticed PSA progression in some of our patients (pts) during docetaxel treatment and reviewed their outcomes. Methods: Men with MHSPC treated with docetaxel were identified from an electronic oncology pharmacy database. Eligible pts were prescribed docetaxel for metastatic adenocarcinoma of the prostate within 120 days of initiation of ADT. Pts with castration-resistant disease (CRPC), other histologies, and those without metastatic disease were excluded. Demographic, clinical, treatment and outcome data were extracted retrospectively from electronic medical records. Results: 31 eligible pts with MHSPC treated with docetaxel between August 2014 and July 2016 were identified. Median age was 65 years (53-83) and 28 (90%) had high-volume disease as defined by Sweeney et al (2015). Nadir PSA levels 6-7 months from ADT initiation were < 0.2, 0.2-4, and > 4 ng/mL in 29.0%, 36.7% and 36.7%, respectively. At median follow up of 85 weeks, 45.2% of pts had progressed to CRPC and 22.6% had died. Median time to CRPC was 59 weeks and median overall survival was 85 weeks. Seven pts with high-volume disease (25%) had PSA progression while receiving docetaxel treatment. The median overall survival of this group was 26 weeks (17 to 106+) and six have died. Three had visceral metastases. Nadir PSA was < 0.2 (1 pt), 0.2-4 (2 pts) and > 4 ng/mL (4 pts). After docetaxel 2 pts received BSC alone and 5 pts had 1st-line CRPC therapy. No response to abiraterone/enzalutamide was seen (3 pts). Two pts who discontinued docetaxel immediately at PSA progression and were switched to alternative chemotherapy survived > 1 year. Conclusions: A subset of men with MHSPC has lethal docetaxel-resistant disease characterized by early PSA rise. It is important to recognize these patients, but it is not clear if standard CRPC therapies are effective. An immediate early switch to alternative chemotherapy may be helpful. Further research to predict early docetaxel resistance, characterize response to current therapies and identify more effective treatment is needed.

Utility of annual screening serum testosterone level in men on surveillance for clinical stage I testicular cancer

144

Background: Testicular cancer occurs in young men and is usually cured leaving survivors with many life years at risk from long term treatment effects. Risks increase with treatment intensity and include cardiovascular disease associated with the metabolic syndrome (Haugnes 2012, de Haas 2013). Testosterone deficiency (TD) is associated with metabolic syndrome & reduced QoL (Huddart 2005). Serum testosterone levels (STLs) are also influenced by underlying testicular dysgenesis & the effects of ageing (Skakkebaek 2001, Oldenburg 2016). We added annual screening STL to our surveillance protocols in 2013 & reviewed the value of this practice. Methods: Men followed in our Testicular Surveillance Clinic from 01 Jan 2006 to 31 Dec 2015 were identified electronically & data extracted retrospectively. Men eligible for this analysis had clinical stage I (CS I) testicular cancer treated with unilateral orchiectomy alone. Outcomes of interest were STLs, Endocrinology referral (Endo) & treatment with androgen replacement therapy (ART). TD was defined by 3 cutoffs of most recent screening STL: < 8.6 nmol/L [age 20-49] (or < 6.7 nmol/L [age > 50]) (local laboratory), < 10.1 nmol/L (Huddart 2005), or < 12.1 nmol/L (EAA & EAU). Results: 77 eligible men were identified: median age 34 years (range, 15-65), seminoma/nonseminoma/mixed/other (45/27/4/1). By the 3 STL cutoffs, TD was present in 13 (16.9% [95%CI, 9.3-27.1%), 22 (28.6% [18.8-40.0%] & 37 (48.1% [36.5-59.7%]); respectively. Nine men (11.4%) were referred to Endo, 1 had morning STL pending & 1 was using OTC ART. Of 8 men assessed by Endo, 5 (6.5%) were prescribed ART. Six men had no screening STL done (3 nonadherent, 1 prostate cancer & 2 unknown). Two men were discharged from clinic with unequivocal low STL. Conclusions: Annual screening STL appears to be useful and may be necessary. 15 CS I men (19.5%) in our clinic had unequivocal TD &/or were referred to an Endo. An additional 20 men (26%) had STLs in a range associated with reduced QoL. Almost half had STLs considered suitable for ART in the presence of symptoms. Two men (2.6%) were discharged with low STLs unaddressed. Guidelines for the optimal assessment and management of men with positive screening for TD are needed.

Burden of illness for metastatic melanoma in Canada, 2011-2013

BACKGROUND

Detailed epidemiology for patients with advanced metastatic melanoma in Canada is not well characterized. We conducted an analysis of patients with this disease in the province of Ontario, with the aim being to study the presentation, disease characteristics and course, and treatment patterns for malignant melanoma.

METHODS

In this Canadian observational prospective and retrospective study of patients with malignant melanoma, we used data collected in the Canadian Melanoma Research Network (cmrn) Patient Registry. We identified patients who were seen at 1 of 3 cancer treatment centres between April 2011 and 30 April 2013. Patient data from 2011 and 2012 were collected retrospectively using chart records and existing registry data. Starting January 2013, data were collected prospectively. Variables investigated included age, sex, initial stage, histology, mutation type, time to recurrence, sites of metastases, resectability, and previous therapies.

RESULTS

A cohort of 810 patients with melanoma was identified from the cmrn registry. Mean age was 58.7 years, and most patients were men (60% vs. 40%). Factors affecting survival included unresectable or metastatic melanoma, initial stage at diagnosis, presence of brain metastasis, and BRAF mutation status. The proportion of surviving patients decreased with higher initial disease stages.

CONCLUSIONS

Using registry data, we were able to determine the detailed epidemiology of patients with melanoma in the Canadian province of Ontario, validating the comprehensive and detailed information that can be obtained from registry data.

Change in International mRCC Database Consortium (IMDC) prognostic category and implications for efficacy of second-line targeted therapy

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Background: Currently no predictive markers exist for choosing second-line targeted therapy (2L) in metastatic renal cell carcinoma (mRCC). A change in IMDC prognostic group when calculated at first-line therapy (1L) and 2L and its association with 2L efficacy was examined. Methods: The IMDC database was interrogated for patients who received 1L VEGF inhibitors (VEGFi) and then 2L with VEGFi or an mTOR inhibitor (mTORi). IMDC prognostic categories (Favorable, F; Intermediate, I; Poor, P) were defined prior to each line of therapy. Overall survival (OS), time to treatment failure (TTF) and response to 1L or 2L were assessed in relation to change in IMDC prognostic risk category. Results: Data for 1516 patients were analyzed; 89% had clear cell histology. Prognostic risk categories at 1L were F: 21.7%; I: 59.5%; P: 18.8%. 60.3% of patients remained in the same risk category at start of 2L; 9.0% improved (3% I→F; 6% P→I); 30.7% deteriorated (14% F → I or P; 16% I → P). Improvement in prognostic risk category was associated with better response and longer duration of 1L. Patients who improved prognostic risk (I → F or P → I), or maintained I or F grouping, had longer TTF if they remained on VEGFi for 2L compared to those who switched to mTORi (p < 0.05). In contrast, patients whose risk category deteriorated (F → I or P) may be more likely to benefit from switching to mTORi. Conclusions: Changes in IMDC prognostic category may predict the subsequent clinical course of patients with aRCC and provide a rational basis for selection of subsequent therapy. [Table: see text]

First-line sunitinib versus pazopanib in metastatic renal cell carcinoma (mRCC): Results from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)

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Background: Sunitinib (SU) and Pazopanib (PZ) have been compared head-to-head in the first-line phase III COMPARZ study in metastatic renal cell carcinoma (mRCC). We compared SU versus PZ, to confirm outcomes and subsequent second-line therapy efficacy in a population-based setting. Methods: We used the IMDC to assess overall survival (OS), progression-free survival (PFS), response rate (RR) and performed proportional hazard regression adjusting for IMDC prognostic groups. Second-line OS2 and PFS2 were also evaluated. Results: We obtained data from 3,606 patients with mRCC treated with either first line SU (n=3226) or PZ (n=380) with an overall median follow-up of 43.5 months (m) (CI95% 41.4 – 46.4). IMDC risk group distribution for favorable prognosis was 440 (17.3%) for SU vs 72 (25%) for PZ, intermediate prognosis 1414 (55.6%) for SU vs 153 (53%) for PZ, poor prognosis 689 (27.1%) for SU vs 62 (22%) for PZ, p= 0.0027. We found no difference between SU vs. PZ for OS (20.1 [CI95% 18.76-21.42] vs. 23.68 m [CI95% 19.54 - 28.81] p=0.19), PFS (7.22 [CI95% 6.76 - 7.78] vs. 6.83 m [CI95% 5.58 - 8.27] p=0.49). The RR was similar in both groups (Table 1). Adjusted HR for OS and PFS were 0.952 (CI95% 0.788 – 1.150 p=0.61) and 1.052 (CI95% 0.908 – 1.220 p = 0.49), respectively. We also found no difference in any second-line treatment between either post-SU vs. post-PZ groups for OS2 (12.88 [CI95% 11.89 – 14.19] vs. 12.91 m [CI95% 10.3 – 19.1] p=0.47) and PFS2 (3.67 [CI95% 3.38 – 3.87] vs. 4.53 m [CI95% 3.08 – 5.35] p=0.4). There was no statistical difference in OS2 and PFS2 if everolimus was used after SU or PZ (p = 0.33 and p = 0.41, respectively) or if axitinib was used after SU or PZ (p = 0.73 and p = 0.72, respectively). Conclusions: We confirmed in real world practice, that SU and PZ have similar efficacy in the first-line setting for mRCC and do not affect outcomes with subsequent second-line treatment. [Table: see text]

Vismodegib in patients with advanced basal cell carcinoma (STEVIE): a pre-planned interim analysis of an international, open-label trial

BACKGROUND

The Hedgehog pathway inhibitor vismodegib has shown clinical benefit in patients with advanced basal cell carcinoma and is approved for treatment of patients with advanced basal cell carcinoma for whom surgery is inappropriate. STEVIE was designed to assess the safety of vismodegib in a situation similar to routine practice, with a long follow-up.

METHODS

In this multicentre, open-label trial, adult patients with histologically confirmed locally advanced basal cell carcinoma or metastatic basal cell carcinoma were recruited from regional referral centres or specialist clinics. Eligible patients were aged 18 years or older with an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, and adequate organ function. Patients with locally advanced basal cell carcinoma had to have been deemed ineligible for surgery. All patients received 150 mg oral vismodegib capsules once a day on a continuous basis in 28-day cycles. The primary objective was safety (incidence of adverse events until disease progression or unacceptable toxic effects), with assessments on day 1 of each treatment cycle (28 days) by principal investigator and coinvestigators at the site. Efficacy variables were assessed as secondary endpoints. The safety evaluable population included all patients who received at least one dose of study drug. Patients with histologically confirmed basal cell carcinoma who received at least one dose of study drug were included in the efficacy analysis. An interim analysis was pre-planned after 500 patients achieved 1 year of follow-up. This trial is registered with ClinicalTrials.gov, number NCT01367665. The study is still ongoing.

FINDINGS

Between June 30, 2011, and Nov 6, 2014, we enrolled 1227 patients. At clinical cutoff (Nov 6, 2013), 499 patients (468 with locally advanced basal cell carcinoma and 31 with metastatic basal cell carcinoma) had received study drug and had the potential to be followed up for 12 months or longer. Treatment was discontinued in 400 (80%) patients; 180 (36%) had adverse events, 70 (14%) had progressive disease, and 51 (10%) requested to stop treatment. Median duration of vismodegib exposure was 36·4 weeks (IQR 17·7-62·0). Adverse events happened in 491 (98%) patients; the most common were muscle spasms (317 [64%]), alopecia (307 [62%]), dysgeusia (269 [54%]), weight loss (162 [33%]), asthenia (141 [28%]), decreased appetite (126 [25%]), ageusia (112 [22%]), diarrhoea (83 [17%]), nausea (80 [16%]), and fatigue (80 [16%]). Most adverse events were grade 1 or 2. We recorded serious adverse events in 108 (22%) of 499 patients. Of the 31 patients who died, 21 were the result of adverse events. As assessed by investigators, 302 (66·7%, 62·1-71·0) of 453 patients with locally advanced basal cell carcinoma had an overall response (153 complete responses and 149 partial responses); 11 (37·9%; 20·7-57·7) of 29 patients with metastatic basal cell carcinoma had an overall response (two complete responses, nine partial responses).

INTERPRETATION

This study assessed the use of vismodegib in a setting representative of routine clinical practice for patients with advanced basal cell carcinoma. Our results show that treatment with vismodegib adds a novel therapeutic modality from which patients with advanced basal cell carcinoma can benefit substantially.

FUNDING

F Hoffmann-La Roche.

Third-line therapy in metastatic renal cell carcinoma: Results from the International mRCC Database Consortium

430

Background: Third-line targeted therapy efficacy in metastatic renal cell carcinoma (mRCC) is not well characterized and many funding bodies do not provide reimbursement for it. Methods: The International mRCC Database Consortium (IMDC) consists of consecutive patient series from 25 cancer centers. It was queried for specific sequences of targeted therapy and third-line therapy. Kaplan Meier estimates were used for survival. Cox proportional hazards models were used to adjust hazard ratios for confounders. Patients that stopped second-line therapy were divided into two groups: those that went onto third-line therapy and those did not. Results: 4,050 patients were treated with first-line targeted therapy, of which 2,011 (49.6%) had second-line therapy and 879 (21.7%) had third-line targeted therapy. The most common third-line therapies were everolimus 25%, sorafenib 14%, sunitinib 13%, temsirolimus 11%, pazopanib 10%, and axitinib 6%. IMDC prognostic groups at third-line therapy initiation were 6% favorable risk, 67% intermediate risk, and 27% poor risk. Overall response rate for third-line therapy was 10.5% and 50.9% had stable disease in those patients that were evaluable. Median PFS was 5.1 months (95% CI, 4.5-5.7) and median OS from third-line therapy initiation was 12.0 months (95% CI, 10.7-12.9). Patients stopping second-line therapy that move on to third-line therapy vs. those that do not receive third line therapy have a median OS from stopping second-line therapy of 13.1 vs. 2.3 mons (p<0.0001). When adjusted for second-line IMDC prognostic criteria and KPS at second-line treatment cessation, patients who do receive third-line therapy have a HR of death of 0.41 (95% CI, 0.32-0.52; p<0.0001) compared to those that do not receive third-line therapy. This may be in part due to patient selection. To further limit bias, when excluding patients that live less than 3 months after second-line therapy cessation, the adjusted HR was similar. Conclusions: Third-line targeted therapy has demonstrated activity and is prevalent in use. Further studies are required to determine appropriate sequencing.

Biomarker use is associated with reduced clinical trial failure risk in metastatic melanoma

Given the high morbidity and mortality associated with metastatic melanoma, considerable attention has been paid to identifying potential therapies. Until recently, few therapies have been specifically approved for treating metastatic melanoma. In an attempt to increase clinical trial successes, many therapies are implementing biomarkers for patient stratification. This strategy narrows down the population in an effort to identify appropriate subpopulations that have increased efficacy or fewer safety concerns. However, the addition of a biomarker constitutes an additional risk to clinical development and may therefore increase the overall clinical trial risk. Here, we examine the clinical trial success rate for therapies targeting metastatic melanoma. In addition, we identify the impact that biomarkers have had on the clinical development of this disease.

ECF chemotherapy for liver metastases due to castration-resistant prostate cancer

INTRODUCTION

Most men with metastatic castration-resistant prostate cancer (CRPC) have biochemical response to docetaxel, but the objective response rate is low. Liver metastases are uncommon with CRPC and associated with shorter survival. More active treatment might benefit these patients. Epirubicin, cisplatin and flurouracil (ECF) is a standard regimen for gastric cancer and response in CRPC liver metastases has been reported. We reviewed our experience with ECF in CRPC with the primary objective of determining its anti-tumour activity in patients with liver metastatic CRPC.

METHODS

Men with CRPC treated with ECF were identified from electronic databases and data were extracted from medical records. Men with tumours showing neuroendocrine features were excluded.

RESULTS

In total, we identified 14 CRPC patients treated with ECF were identified, of which 8 had liver metastases. The median age was 56 (range: 42-76) and all had multiple poor prognostic features. A median of 6 cycles of ECF were administered (range: 1-10) and toxicities were similar to previous reports. Of the 8 patients with liver metastases, 5 had partial remission.

CONCLUSIONS

ECF was highly active in this small selected group of younger men with liver metastases from CRPC and multiple poor prognostic features. Despite important limitations, this is the third report of high objective response rates with ECF in CRPC. Objective response rates are low with current monotherapies. A higher probability of ORR is preferred for critical organ disease, therefore the anti-tumour activity should encourage testing of ECF in comparison to the most active current therapies.

Cytoreductive nephrectomy in patients with synchronous metastases from renal cell carcinoma: results from the International Metastatic Renal Cell Carcinoma Database Consortium

BACKGROUND

The benefit of cytoreductive nephrectomy (CN) for overall survival (OS) is unclear in patients with synchronous metastatic renal cell carcinoma (mRCC) in the era of targeted therapy.

OBJECTIVE

To determine OS benefit of CN compared with no CN in mRCC patients treated with targeted therapies.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective data from patients with synchronous mRCC (n=1658) from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) were used to compare 982 mRCC patients who had a CN with 676 mRCC patients who did not.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

OS was compared and hazard ratios (HRs) adjusted for IMDC poor prognostic criteria.

RESULTS AND LIMITATIONS

Patients who had CN had better IMDC prognostic profiles versus those without (favorable, intermediate, or poor in 9%, 63%, and 28% vs 1%, 45%, and 54%, respectively). The median OS of patients with CN versus without CN was 20.6 versus 9.5 mo (p<0.0001). When adjusted for IMDC criteria to correct for imbalances, the HR of death was 0.60 (95% confidence interval, 0.52-0.69; p<0.0001). Patients estimated to survive <12 mo may receive marginal benefit from CN. Patients who have four or more of the IMDC prognostic criteria did not benefit from CN. Data were collected retrospectively.

CONCLUSIONS

CN is beneficial in synchronous mRCC patients treated with targeted therapy, even after adjusting for prognostic factors. Patients with estimated survival times <12 mo or four or more IMDC prognostic factors may not benefit from CN. This information may aid in patient selection as we await results from randomized controlled trials.

PATIENT SUMMARY

We looked at the survival outcomes of metastatic renal cell carcinoma patients who did or did not have the primary tumor removed. We found that most patients benefited from tumor removal, except for those with four or more IMDC risk factors.

The International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model as a prognostic tool in metastatic renal cell carcinoma (mRCC) patients previously treated with first-line targeted therapy (TT)

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Background: Prior prognostic models for 2nd-line systemic therapy have not been studied in the setting of contemporary sequential targeted therapy (TT). We sought to validate the IMDC prognostic model in patients with mRCC receiving next-line TT after progression on 1st-line TT. Methods: Patients who received 2nd-line TT after progressing on 1st-line TT for mRCC at 19 centres were analyzed. For the patients who had immunotherapy (22%) prior to their 1st TT, we examined their second TT (ie 3rd-line therapy). The endpoint was median overall survival (OS) since the initiation of 2nd-line therapy. Additionally, we compared the IMDC model with the 3-factor-MSKCC model (Motzer et al JCO 2004) used for previously-treated patients. Results: 1,021 patients treated with a second TT were included. Median time on 2nd-line TT was 3.9 months (range 0-76+). 871 (85%) of patients had stopped 2nd-line TT by the time of analysis. Median OS since 2nd-line TT was 12.5 months (95% CI: 11.3-14.3 months), with 369 (36.1%) of patients remaining alive. 5 out of 6 pre-defined factors in IMDC model (anemia, thrombocytosis, neutrophilia, KPS <80%, and <1 year from diagnosis to treatment) measured at the time of 2nd-line TT were independent predictors of poorer OS (HR between 1.39 and 1.58, p<0.05). Hypercalcemia was not statistically significant in multivariable analysis (p=0.3008) likely due to the low incidence of hypercalcemia (9%). The concordance index using all 6 prognostic factors was 0.70, and was 0.66 with the 3-factor-MSKCC model. When patients were divided into 3 risk categories using IMDC criteria, median OS was 35.8 months (95% CI 28.3-47.8) in the favorable risk group (n=76), 16.6 months (95% CI 14.9-17.9) in the intermediate risk group (n=529), and 5.4 months (95% CI 4.7-6.8) in the poor risk group (n=261). Conclusions: The IMDC prognostic model has been validated in and can be applied to patients previously treated with TT, in addition to previously validated populations in 1st-line TT and non-clear cell setting.

Cytoreductive nephrectomy (CN) in patients with synchronous metastases from renal cell carcinoma: Results from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)

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Background: The role of cytoreductive nephrectomy is unclear in patients with synchronous metastases from renal cell carcinoma (RCC) in the age of targeted therapy. Methods: Comparisons were made between patients treated with targeted therapy who had a CN versus not and adjusted using proportional hazards regression for known poor prognostic criteria (IMDC criteria Heng et al JCO 2009). Results: 2569/3245 (79%) mRCC patients received a nephrectomy. Patients who had nephrectomy before the diagnosis of metastatic disease were excluded (n=1634). Among the remaining patients, 935 patients had a CN and 676 patients did not have nephrectomy. All patients received targeted therapy with the majority receiving first-line sunitinib 72%, sorafenib 15%, temsirolimus 5%, bevacizumab 3%, pazopanib 3%. Patients who had CN had better IMDC prognostic profiles versus those without (favorable/intermediate/poor in 9%/63%/28% vs 1%/45%/54% p<0.0001). The median overall survival of patients with CN vs without was 20.6 vs 9.5 months (p<0.0001). When adjusted for IMDC criteria to correct for imbalances, the HR of death was 0.60 (95%CI 0.52-0.69, p<0.0001). The Table demonstrates the increasing benefit of CN if a given patient has a longer survival time. Conclusions: CN can be beneficial in patients with synchronous metastatic RCC even after adjustment for prognostic factors. Patients who are estimated to survive less than 9-12 months may have a marginal benefit compared to those with longer estimated survival. This may aid in patient selection as we await results from randomized controlled trials. [Table: see text]