Kimberly D Allman

A Phase II Study of Intermittent Sunitinib in Previously Untreated Patients With Metastatic Renal Cell Carcinoma

Purpose Sunitinib is a standard initial therapy in metastatic renal cell carcinoma (mRCC), but chronic dosing requires balancing toxicity with clinical benefit. The feasibility and clinical outcome with intermittent sunitinib dosing in patients with mRCC was explored. Patients and Methods Patients with treatment-naïve, clear cell mRCC were treated with four cycles of sunitinib (50 mg once per day, 4 weeks of receiving treatment followed by 2 weeks of no treatment). Patients with a ≥ 10% reduction in tumor burden (TB) after four cycles had sunitinib held, with restaging scans performed every two cycles. Sunitinib was reinitiated for two cycles in those patients with an increase in TB by ≥ 10%, and again held with ≥ 10% TB reduction. This intermittent sunitinib dosing continued until Response Evaluation Criteria in Solid Tumors-defined disease progression while receiving sunitinib, or unacceptable toxicity occurred. The primary objective was feasibility, defined as the proportion of eligible patients who underwent intermittent therapy. Results Of 37 patients enrolled, 20 were eligible for intermittent therapy and all patients (100%) entered the intermittent phase. Patients were not eligible for intermittent sunitinib because of progressive disease (n = 13), toxicity (n = 1), or consent withdrawal (n = 3) before the end of cycle 4. The objective response rate was 46% after the first four cycles of therapy. The median increase in TB during the periods off sunitinib was 1.6 cm (range, -2.9 to 3.4 cm) compared with the TB immediately before stopping sunitinib. Most patients exhibited a stable sawtooth pattern of TB reduction while receiving sunitinib and TB increase while not receiving sunitinib. Median progression-free survival to date is 22.4 months (95% CI, 5.4 to 37.6 months) and median overall survival is 34.8 months (95% CI, 14.8 months to not applicable). Conclusion Periodic extended sunitinib treatment breaks are feasible and clinical efficacy does not seem to be compromised.

Clinical Effect of Dose Escalation After Disease Progression in Patients With Metastatic Renal Cell Carcinoma

Micro‐Abstract Patients taking tyrosine kinase inhibitors (TKIs) for metastatic renal cell carcinoma might benefit from dose escalation at the occurrence of progressive disease (PD). The data from patients who underwent TKI dose escalation at PD were retrospectively reviewed. The median duration of therapy after PD (10.1 months) was longer than that before PD (6.8 months), suggesting an antitumor effect with TKI dose escalation at PD. Background: Given the variability in drug levels with tyrosine kinase inhibitors (TKIs) in patients with metastatic renal cell carcinoma (mRCC), dose escalation at the occurrence of progressive disease (PD) might have antitumor effects. Patients and Methods: The data from patients with mRCC who were treated at the Cleveland Clinic with TKIs and received a dose escalation after PD in accordance with Response Evaluation Criteria In Solid Tumors (RECIST), version 1.1, were retrospectively reviewed. Patient‐ and disease‐related data were collected and summarized as frequency counts and percentages or medians and ranges. The Kaplan‐Meier method was used to summarize the treatment duration for the escalated doses. Results: Twenty‐two patients were identified. Most patients (82%) were men; the median age at diagnosis was 58 years (range, 40‐71 years). The most common histologic type was clear cell (73%). Axitinib was the most frequently escalated agent after PD (17 patients), followed by sunitinib (3 patients), and pazopanib (2 patients). Before PD, the median treatment duration was 6.8 months (range, 1.6‐50.6 months). Of the 18 patients with evaluable tumor measurements after dose escalation, 14 (78%) had a decrease in tumor burden. The median decrease in tumor burden after dose escalation was 14% (range, 2%‐58%); 4 patients (22%) had decreases ≥10%, 2 (11%) ≥20%, and 4 (22%) >30% (RECIST partial response). At the last follow‐up examination, 5 patients (23%) continued to be treated at escalated doses. The median duration of escalated therapy was estimated at 10.1 months (range, 0.6 to 37.9 months). Conclusion: Dose escalation of TKIs after PD for select patients with mRCC can lead to a reduction in tumor burden and extend the duration of therapy.

The association between facility case volume and overall survival in patients with metastatic renal cell carcinoma in the targeted therapy era

BACKGROUND Improved overall survival of cancer patients treated by high-volume providers has been reported in surgical oncology and radiation oncology literature. Whether this volume-outcome association exists in medical oncology-managed metastatic solid tumors is uncertain. This study aimed to investigate the effect of facility case volume (FCV) on overall survival in patients with metastatic renal cell carcinoma (mRCC) diagnosed in the targeted therapy era. MATERIALS AND METHODS Adult patients diagnosed with mRCC between 2006 and 2015 were identified in the National Cancer Database. The primary exposure was FCV, which was defined by mRCC case volume of each treating facility. The association between FCV and all-cause mortality in mRCC was investigated in multivariable Cox regression model and validated with inverse propensity-score weighting method. Logistic regression was used to identify independent predictors for treatment at high-volume facilities. Covariates adjusted for were sociodemographics, tumor characteristics and treatment modalities. RESULTS There were 31,329 mRCC patients identified. The mean follow-up time was 14.3 months. When FCV was coded as a continuous variable, each increment of 10 mRCC cases/y was associated with reduced all-cause mortality after baseline covariates adjustment [adjusted hazard ratio: 0.93, 95% confidence interval: 0.90-0.96, P value:<0.0001]. In dichotomized models, improved all-cause mortality was observed at cutoffs of 85th (4.3 cases/y), 90th (5.4 cases/y) and 95th (7.4 cases/y) but not at 50th (2.2 cases/y) and 75th (3.4 cases/y) percentiles. For illustrative purpose, 95th percentile was chosen and inverse propensity-score weighting-adjusted Kaplan-Meier curve demonstrated improved overall survival for mRCC patients treated at high-volume facilities (adjusted hazard ratio: 0.90, 95% confidence interval: 0.88-0.94, P value <0.0001; the 1-, 2-, 3-year survival rates were 41%, 26%, and 19% vs. 36%, 22%, and 16% for patients treated at high and low-volume facilities, respectively). Patients without insurance or with Medicaid status, with shorter travel distance, living in nonmetropolitan area or in area with lower averaged education level were less likely to be treated at high-volume facilities. CONCLUSIONS Patients diagnosed with mRCC in the targeted therapy era have improved overall survival when treated at high mRCC-volume facilities, suggesting a volume-outcome association in medical oncology-managed metastatic solid tumors.

The efficacy of VEGFR TKI therapy after progression on immune combination therapy in metastatic renal cell carcinoma

BACKGROUNDThe outcome of patients who progress on front-line immune-based combination regimens (IC) including immune checkpoint inhibitors (CPI) and receive subsequent systemic therapy is unknown.MethodsRetrospective analysis of consecutive patients with clear-cell mRCC who progressed on one of seven clinical trials investigating an IC and received ≥1 line of subsequent VEGFR TKI therapy.ResultsThirty-three patients [median age 57 (37–77), 85% male, 73% ECOG 0] were included. For evaluable patients (N = 28), the best response to first subsequent therapy was 29% partial response, 54% stable disease, and 18% progressive disease. The median PFS (mPFS) for first subsequent therapy was 6.4 months (95% CI, 4.4–8.4); no difference in mPFS by prior type of IC (VEGFR TKI-CPI vs. CPI-CPI) was noted (p = 0.310). Significant AEs were observed in 30% of patients, more frequently transaminitis (9%).ConclusionsVEGFR TKIs have clinical activity in mRCC refractory to IC therapy, possibly impacted by the mechanism of prior combination therapy.