Real-world Clinical Outcomes of Pazopanib Immediately After Discontinuation of Immunotherapy for Advanced Renal Cell Carcinoma.

INTRODUCTION: In the first-line (1L) setting, pazopanib (PAZ) has been recommended by the National Comprehensive Cancer Network for the treatment of advanced renal cell carcinoma (aRCC). In 2018, immuno-oncology (IO) therapy became a commonly used 1L treatment option for aRCC. We report the real-world clinical outcomes of PAZ after IO therapy for patients with aRCC. MATERIALS AND METHODS: We performed a longitudinal, retrospective medical record review study. The included patients were aged ≥ 18 years, had initiated second-line and/or beyond PAZ after IO therapy for clear cell aRCC on or before October 2017, and had complete medical records available from the diagnosis of aRCC to the discontinuation of PAZ, death, or the medical record extraction date (May 2018), whichever occurred first. The primary outcome variable was the PAZ duration of therapy. The secondary outcomes were progression-free survival and overall survival since PAZ initiation, the reasons for PAZ discontinuation, and the occurrence of adverse events (AEs). RESULTS: A total of 258 eligible patients had initiated IO therapies before PAZ as follows: nivolumab (68%), nivolumab plus ipilimumab (14%), pembrolizumab (12%), and ipilimumab (3%). Overall, the median PAZ duration of therapy was 13.4 months (95% confidence interval [CI], 10.1-16.0 months). The median progression-free survival with PAZ after IO therapy was 13.5 months (95% CI, 11.8 months to not reached). The estimated overall survival rate of PAZ after IO therapy at 6 and 12 months was 93% and 89%, respectively. A total of 109 patients (42%) had reported an AE. The most frequently reported AEs were fatigue (29%) and diarrhea (14%). No additional safety signal of hepatotoxicity was observed (increased aspartate aminotransferase, 5%; increased alanine transaminase, 6%). CONCLUSIONS: In the present real-world study, second-line and/or beyond PAZ after previous IO therapy was well-tolerated and effective for patients with aRCC.

Germline Variant in SLCO2B1 and Response to Abiraterone Acetate Plus Prednisone (AA) in New-onset Metastatic Castration-resistant Prostate Cancer (mCRPC).

There are many treatment options available for men with metastatic castration-resistant prostate cancer (mCRPC). Yet, biomarkers predictive of differential response to treatment are currently unavailable. A recent translational study suggested that SLCO2B1 genotype could predict response to abiraterone acetate for men with advanced prostate cancer. Here, we investigate whether germline variants in SLCO2B1 are predictive of response to first-line abiraterone acetate in men with new mCRPC. Clinical data and samples were analyzed from a prospective prostate cancer registry at the University of Utah (Salt Lake City, UT). Genotyping was performed using the Illumina OmniExpress genotyping platform. Primary endpoint was progression-free survival (PFS) on first-line abiraterone acetate in men with mCRPC. We performed a prespecified multivariate Cox regression analysis to assess the independent predictive value of rs12422149 and rs1789693 on PFS on abiraterone acetate. Of 401 men with advanced prostate cancer genotyped, 323 were homozygous wild-type for rs12422149 (80.5%), 74 were heterozygous (18.5%), and 4 were homozygous variant (1.0%). In a multivariate analysis of 79 men treated with first-line abiraterone acetate for mCRPC, men heterozygous for rs12422149 had significantly improved median PFS compared with the homozygous wild-type group (8.9 months vs. 6.3 months; HR, 0.46; 95% confidence interval, 0.23-0.94; P = 0.03). No significant difference in median PFS was seen by rs1789693 genotype. In this first clinical validation of translational data reported by Mostaghel and colleagues, germline variant alleles in rs12422149 of SLCO2B1 are common and predict improved response to first-line abiraterone acetate in men with mCRPC.

Germline Variant in HSD3B1 (1245 A > C) and Response to Abiraterone Acetate Plus Prednisone in Men With New-Onset Metastatic Castration-Resistant Prostate Cancer.

BACKGROUND: The HSD3B1 gene encodes the enzyme 3ß-hydroxysteroid dehydrogenase-1 (3ßHSD1), which catalyzes adrenal androgen precursors into dihydrotestosterone, the most potent androgen. Recently, the HSD3B1 (1245C) variant was shown to predict shorter duration of response to androgen deprivation therapy with medical or surgical castration in the setting of castration-sensitive prostate cancer (CSPC). The HSD3B1 (1245C) variant also predicts longer duration of response to ketoconazole in men with castration-resistant prostate cancer (CRPC). We hypothesized that the HSD3B1 (1245C) variant predicts response to treatment with abiraterone acetate (AA) and can help personalize treatment in men with advanced prostate cancer. METHODS: Clinical data and samples were from a prospectively maintained prostate cancer registry at the University of Utah. Genotyping was performed. The primary study end point was progression-free survival in first-line AA in men with metastatic CRPC. We performed prespecified multivariate analyses to assess the independent predictive value of HSD3B1 genotype on progression-free survival on AA. RESULTS: Seventy-six men with metastatic CRPC treated with first-line AA were included. In multivariate analysis, the HSD3B1 (1245C) variant did not predict response to first-line AA. CONCLUSION: The HSD3B1 (1245C) variant does not predict response to first-line AA in metastatic CRPC. This finding could be due to the ability of AA metabolites to act as both agonist (3-keto-5α-abiraterone) and antagonist (Δ4-abiraterone) on androgen signaling.

Effect of treatment dose reductions in the setting of hand-foot syndrome on survival outcomes in patients with metastatic renal cell carcinoma treated with vascular endothelial growth factor receptor inhibitors.

Purpose Hand-foot syndrome is a common dose limiting toxicity of vascular endothelial growth factor receptor tyrosine kinase inhibitors used for treatment of patients with metastatic renal cell carcinoma. The effect of treatment dose reductions, in the context of hand-foot syndrome, on survival outcomes is reported. Methods This was a retrospective case series of patients receiving vascular endothelial growth factor receptor tyrosine kinase inhibitors from 1 January 2004 to 31 October 2013. The main outcomes were progression-free and overall survival in these patients experiencing hand-foot syndrome and undergoing treatment dose reductions. Univariate and multivariate analyses were conducted utilizing Kaplan-Meier method and COX Proportional Hazard model with landmark analyses at 2 months. Results Of the 120 patients evaluated, treatment dose reductions for any reason were required in 68 (56.7%) patients. The most common reasons for treatment dose reductions were mucositis, hand-foot syndrome, and fatigue. The median progression-free survival and overall survival were significantly longer in patients with hand-foot syndrome with or without treatment dose reductions as compared to those without hand-foot syndrome. Conclusions An improvement in survival outcomes was observed in metastatic renal cell carcinoma patients with treatment-associated hand-foot syndrome despite treatment dose reductions. These data need validation in a larger cohort to confirm the hypothesis that treatment dose reductions in the setting of hand-foot syndrome do not negatively impatient survival.

Incidence and Characterization of Antiandrogen Withdrawal Syndrome After Discontinuation of Treatment With Enzalutamide in Castration-resistant Prostate Cancer.

BACKGROUND: Antiandrogen withdrawal syndrome (AAWS), manifested as a prostate-specific antigen (PSA) decline after discontinuation of a first-generation antiandrogen has been well characterized. The objective of the present study was to assess the incidence of AAWS with enzalutamide in men with metastatic castration-resistant prostate cancer. PATIENTS AND METHODS: Patients from a single-institution cohort with metastatic castration-resistant prostate cancer who had discontinued enzalutamide after PSA or radiographic progression were included. AAWS after enzalutamide was defined as any PSA decline after discontinuation of enzalutamide. The baseline patient, disease, and treatment characteristics were compared between patients with and without AAWS after enzalutamide. Statistical analysis of the baseline characteristics included descriptive statistics using the Wilcoxon rank sum test and the Fisher exact test. The median duration of enzalutamide therapy was compared using the log-rank test, and the progression-free survival of the patients with AAWS was evaluated using the Kaplan-Meier method. RESULTS: Of 47 eligible patients, 5 experienced AAWS after enzalutamide discontinuation. The PSA response in these 5 patients was 84%, 32%, 17%, 15%, and 15%. The median AAWS response time until subsequent PSA progression was 3.3 months. No patient, disease, or treatment characteristics differed among the patients with and without AAWS after enzalutamide discontinuation. CONCLUSION: To the best of our knowledge, this is the largest reported cohort documenting the incidence and characterization of AAWS after enzalutamide to date. The AAWS frequency after enzalutamide was low and of short duration. No patient- or disease-related characteristics were associated with AAWS with enzalutamide. The occurrence of AAWS after enzalutamide was not clinically meaningful. Thus, accounting for this phenomenon in clinical practice or trial designs could be unnecessary.

Systemic Immunotherapy for Urothelial Cancer: Current Trends and Future Directions.

Urothelial cancer of the bladder, renal pelvis, ureter, and other urinary organs is the fifth most common cancer in the United States, and systemic platinum-based chemotherapy remains the standard of care for first-line treatment of advanced/metastatic urothelial carcinoma (UC). Until recently, there were very limited options for patients who are refractory to chemotherapy, or do not tolerate chemotherapy due to toxicities and overall outcomes have remained very poor. While the role of immunotherapy was first established in non-muscle invasive bladder cancer in the 1970s, no systemic immunotherapy was approved for advanced disease until the recent approval of a programmed death ligand-1 (PD-L1) inhibitor, atezolizumab, in patients with advanced/metastatic UC who have progressed on platinum-containing regimens. This represents a significant milestone in this disease after a void of over 30 years. In addition to atezolizumab, a variety of checkpoint inhibitors have shown a significant activity in advanced/metastatic urothelial carcinoma and are expected to gain Food and Drug Administration (FDA) approval in the near future. The introduction of novel immunotherapy agents has led to rapid changes in the field of urothelial carcinoma. Numerous checkpoint inhibitors are being tested alone or in combination in the first and subsequent-line therapies of metastatic disease, as well as neoadjuvant and adjuvant settings. They are also being studied in combination with radiation therapy and for non-muscle invasive bladder cancer refractory to BCG. Furthermore, immunotherapy is being utilized for those ineligible for firstline platinum-based chemotherapy. This review outlines the novel immunotherapy agents which have either been approved, or are currently being investigated in clinical trials in UC.

Survival Outcomes and Tumor IMP3 Expression in Patients with Sarcomatoid Metastatic Renal Cell Carcinoma.

Metastatic renal cell carcinoma with sarcomatoid histology (SmRCC) is associated with poor survival. No data is available from randomized trials on the efficacy of vascular endothelial growth factor (VEGF) and mammalian target of rapamycin (mTOR) inhibitors in SmRCC. We identified SmRCC patients from a single institutional database. To identify predictive and prognostic biomarkers, immunohistochemistry (IHC) analysis was performed on the tumor samples for downstream targets of VEGF and mTOR pathways. Survival outcomes were stratified by IHC analysis, extent of sarcomatoid component, Memorial Sloan-Kettering Cancer Center (MSKCC), and Heng risk criteria. Twenty-seven patients with SmRCC were included. First line therapy included targeted therapy (n = 19), immunotherapy (n = 4), cytotoxic chemotherapy (n = 1), and no treatment (n = 3). Median OS was 8.2 months (95% CI 3.8-14.2 months). Median survival in months, based on MSKCC and Heng risk groups, was favorable 89.3 versus 84.5, intermediate 9.5 versus 12.7, and poor 3.9 versus 5.1. None of the IHC markers predicted outcomes of treatment with VEGF or mTOR inhibitors. Only tumor IMP3 expression was associated with inferior OS, although not statistically significant (IMP3 negative 14.2 versus IMP3 positive 4.9 months; HR 0.46, 95% CI 0.16-1.21; P = 0.12). The study was limited by small sample size.

Correlation of degree of hypothyroidism with survival outcomes in patients with metastatic renal cell carcinoma receiving vascular endothelial growth factor receptor tyrosine kinase inhibitors.

BACKGROUND: Hypothyroidism is a common adverse effect of vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR-TKI) therapy in patients with metastatic renal cell carcinoma (mRCC). Some studies have shown an association with improved survival. However, hypothyroidism severity has not been correlated with survival outcomes. We report the incidence and severity of VEGFR-TKI therapy-associated hypothyroidism in correlation with the survival outcomes of patients with mRCC. PATIENTS AND METHODS: A retrospective analysis of patients with mRCC who received VEGFR-TKIs (2004 through 2013) was conducted from a single institutional database. Hypothyroidism, progression-free survival (PFS), and overall survival (OS) were assessed. Univariate and multivariate analyses were performed using the Kaplan-Meier method and Cox proportional hazard models. RESULTS: Of 125 patients with mRCC, 65 were eligible. Their median age was 59 years (range, 45-79 years), and 46 (70.8%) were male. Hypothyroidism occurred in 25 patients (38.5%), of whom 13 had a peak thyroid-stimulating hormone (TSH) level > 10 mIU/L during treatment. The median OS was significantly longer in patients with a peak TSH > 10 mIU/L than in patients with a peak TSH of ≤ 10 mIU/L (not reached vs. 21.4 months, P = .005). On multivariate analysis, risk criteria, number of previous therapies, and severe hypothyroidism (TSH > 10 mIU/L) during VEGFR-TKI therapy remained significant for improvements in PFS and OS. CONCLUSION: The severity of VEGFR-TKI therapy-associated hypothyroidism (TSH > 10 mIU/L) was associated with improved survival outcomes in patients with mRCC and should not necessitate a dose reduction or therapy discontinuation.

Cisplatin-based first-line therapy for advanced urothelial carcinoma after previous perioperative cisplatin-based therapy.

BACKGROUND: Outcomes with cisplatin-based first-line therapy for advanced UC after previous perioperative cisplatin-based chemotherapy are unclear. In this study we evaluated outcomes with a focus on the effect of time from previous cisplatin-based perioperative chemotherapy. PATIENTS AND METHODS: Data were collected for patients who received cisplatin-based first-line therapy for advanced UC after previous perioperative cisplatin-based therapy. Cox proportional hazards models were used to investigate the prognostic ability of visceral metastasis, ECOG PS, TFPC, anemia, leukocytosis, and albumin on overall survival (OS). RESULTS: Data were available for 41 patients from 8 institutions including 31 men (75.6%). The median age was 61 (range, 41-77) years, most received gemcitabine plus cisplatin (n = 26; 63.4%), and the median number of cycles was 4 (range, 1-8). The median OS was 68 weeks (95% confidence interval [CI], 48.0-81.0). Multivariable Cox regression analysis results showed an independent prognostic effect on OS for PS > 0 versus 0 (hazard ratio [HR], 4.56 [95% CI, 1.66-12.52]; P = .003) and TFPC ≥ 78 weeks versus < 78 weeks (HR, 0.48 [95% CI, 0.21-1.07]; P = .072). The prognostic model for OS was internally validated with c-index = 0.68. Patients with TFPC < 52 weeks, 52 to 104 weeks, and ≥ 104 weeks had median survival of 42, 70, and 162 weeks, respectively. CONCLUSION: Longer TFPC ≥ 78 weeks and ECOG PS = 0 were independently prognostic for better survival with cisplatin-based first-line chemotherapy for advanced UC after previous perioperative cisplatin-based chemotherapy. The data support using TFPC ≥ 52 weeks to rechallenge with cisplatin-based first-line chemotherapy for metastatic disease.

Phase Ib/II trial of gemcitabine, cisplatin, and lenalidomide as first-line therapy in patients with metastatic urothelial carcinoma.

BACKGROUND: Outcomes with current chemotherapy in metastatic urothelial carcinoma (MUC) remain poor. Lenalidomide, an antiangiogenic and immunomodulatory agent, enhances the effects of chemotherapy in preclinical studies. In this phase Ib/II study, we sought to determine a tolerable dose of lenalidomide in combination with gemcitabine and cisplatin (GCL) in patients with MUC and to explore the safety and activity of this regimen. METHODS: Patients with chemotherapy-naïve MUC received gemcitabine 1,000 mg/m(2) on days 1 and 8 and cisplatin 70 mg/m(2) on day 1 every 21 days. In phase Ib, there were four planned escalating dose levels of lenalidomide (10, 15, 20, and 25 mg) daily on days 1-14. RESULTS: Seven patients received GCL in phase Ib. The dose of lenalidomide was not escalated beyond 10 mg because of cytopenias requiring repeated dose delays and reductions. Two additional patients were enrolled in phase II, but the study was ultimately terminated due to poor tolerability and slow accrual. The most frequent grade ≥ 3 adverse events were cytopenias and diarrhea. Three of the nine patients experienced an objective response (one complete response, two partial responses). CONCLUSION: Chronic administration of the GCL regimen was poorly tolerated because of additive and cumulative myelosuppression.