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

534

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)

544

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)

398

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]