Rational Approaches to Treatment Duration with Immunotherapy in Metastatic Renal Cell Carcinoma

Toxicity-Induced Discontinuation of Immune Checkpoint Inhibitors in Metastatic Urothelial Cancer: 6-Year Experience from a Specialized Uro-Oncology Center

Immune checkpoint inhibitor (ICI) therapies have been established as the standard-of-care in various uro-oncological cancers. Immune-related adverse events (irAEs) are frequent, but their degree rarely leads to the discontinuation of immunotherapies. Unplanned permanent treatment discontinuation may negatively impact the outcomes of patients, but there are emerging data about a positive correlation between emergence of severe irAEs and therapeutic cancer responses. In this study, a retrospective analysis of patients treated for urothelial carcinoma (UC) with ICI-based immunotherapy was conducted. irAEs were classified according to the Common Terminology Criteria for Adverse Events (CTCAEs) and radiological responses according to the Response Evaluation Criteria In Solid Tumors (RECISTs). Out of 108 patients with metastatic urothelial cancer that underwent immunotherapy, 11 experienced a severe irAE that required permanent discontinuation of ICI therapy. The most frequent irAEs leading to discontinuation were hepatitis (n = 4), pneumonitis (n = 2), and gastritis or colitis (n = 2). Prior to discontinuation (R1), the radiological best response was complete remission (CR) in three patients, partial response (PR) in six, and stable disease (SD) in wo patients. After the discontinuation of ICI therapy (R2), the best responses were CR in six, PR in three, and SD in two patients. Following discontinuation, the majority of these patients showed a sustained treatment response, despite not receiving any cancer-specific treatment. The median time of response after discontinuation of ICI therapy was 26.0 (5.2-55.8) months. We propose accurate counseling and close follow-ups of patients following their discontinuation of ICI therapy due to irAEs, as responses can be durable and deep, and many patients do not require immediate subsequent therapies, even in urothelial cancer. More data are required to find predictors of the length of response to appropriately counsel patients.

Treatment-free survival after discontinuation of immune checkpoint inhibitors in metastatic renal cell carcinoma: a systematic review and meta-analysis

While immune checkpoint inhibitors (ICI) can lead to sustained responses in metastatic renal cell carcinoma (mRCC), the optimal duration of therapy remains unknown. We aimed to examine treatment-free survival (TFS) in objective responders who discontinued ICI and to explore factors that may impact objective response rate (ORR) and TFS. MEDLINE/PubMed, Embase, and the Cochrane Library were searched for prospective studies reporting individual outcomes after ICI discontinuation in patients with mRCC. Pooled ORR and TFS were estimated using random-effects meta-analyses, and associations between ICI regimen type or treatment line and ORR or TFS were evaluated. Sixteen cohorts comprising 1833 patients treated with ICI were included. The pooled ORR was 43% (95% CI 33% to 53%), and significant differences in summary estimates existed among patients who received ICI monotherapy (22%, 95% CI 18% to 26%), ICI plus a vascular endothelial growth factor (VEGF) pathway inhibitor (57%, 95% CI 48% to 65%), and dual ICI (40%, 95% CI 36% to 44%). Of 572 responders who had available data, 327 stopped ICI, with 86 (26%) continuing to respond off-treatment. Pooled TFS rates at 6 and 12 months were 35% (95% CI 20% to 50%) and 20% (95% CI 8% to 35%), respectively, and were highest for responders treated with dual ICI and lowest for those treated with ICI plus a VEGF pathway inhibitor. Thus, a subset of patients with mRCC who are treated with ICI-based therapy can have durable TFS after therapy discontinuation. Prospective clinical trials and biomarkers are needed to identify patients who can discontinue ICI therapy without compromising clinical outcomes.

The role of cytoreductive nephrectomy in renal cell carcinoma patients with liver metastasis

It is widely accepted that renal cell carcinoma (RCC) with liver metastasis (LM) carries a dismal prognosis. We aimed to explore the value of cytoreductive nephrectomy among these patients. Patients were extracted from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2017. The univariate and multivariate Cox proportional hazards models were conducted to select the prognostic predictors of survival. Patients were divided into nephrectomy and non-nephrectomy groups. Propensity score-matching (PSM) analyses were applied to reduce the above factors' differences between the groups. Overall survival (OS) was compared by Kaplan-Meier analyses. Data from 683 patients were extracted from the database. The univariate Cox regression and multivariate Cox regression revealed that factors including age, histologic type, T and N stages, lung metastasis, brain metastasis, and nephrectomy were significant predictors of survival in the patients. After the PSM analyses, we found that nephrectomy prolonged OS. Nephrectomy can prolong OS in eligible RCC patients with LM.

Combining epigenetic and clinicopathological variables improves specificity in prognostic prediction in clear cell renal cell carcinoma

BACKGROUND

Metastasized clear cell renal cell carcinoma (ccRCC) is associated with a poor prognosis. Almost one-third of patients with non-metastatic tumors at diagnosis will later progress with metastatic disease. These patients need to be identified already at diagnosis, to undertake closer follow up and/or adjuvant treatment. Today, clinicopathological variables are used to risk classify patients, but molecular biomarkers are needed to improve risk classification to identify the high-risk patients which will benefit most from modern adjuvant therapies. Interestingly, DNA methylation profiling has emerged as a promising prognostic biomarker in ccRCC. This study aimed to derive a model for prediction of tumor progression after nephrectomy in non-metastatic ccRCC by combining DNA methylation profiling with clinicopathological variables.

METHODS

A novel cluster analysis approach (Directed Cluster Analysis) was used to identify molecular biomarkers from genome-wide methylation array data. These novel DNA methylation biomarkers, together with previously identified CpG-site biomarkers and clinicopathological variables, were used to derive predictive classifiers for tumor progression.

RESULTS

The "triple classifier" which included both novel and previously identified DNA methylation biomarkers together with clinicopathological variables predicted tumor progression more accurately than the currently used Mayo scoring system, by increasing the specificity from 50% in Mayo to 64% in our triple classifier at 85% fixed sensitivity. The cumulative incidence of progress (_pCIP_5yr) was 7.5% in low-risk vs 44.7% in high-risk in M0 patients classified by the triple classifier at diagnosis.

CONCLUSIONS

The triple classifier panel that combines clinicopathological variables with genome-wide methylation data has the potential to improve specificity in prognosis prediction for patients with non-metastatic ccRCC.