Baseline tumor volume in assessing prognosis of patients with intermediate-risk synchronous metastatic renal cell carcinoma

Novel cut-off values of time from diagnosis to systematic therapy predict the overall survival and the efficacy of targeted therapy in renal cell carcinoma: A long-term, follow-up, retrospective study

Objectives

Metastatic renal cell carcinoma can occur synchronously or metachronously. We characterized the time from diagnosis to systematic therapy as a categorical variable to analyze its effect on the overall survival and first‐line treatment efficacy of metastatic renal cell carcinoma patients.

Methods

We initially enrolled 949 consecutive metastatic renal cell carcinoma patients treated with targeted therapies retrospectively from December 2005 to December 2019. X‐tile analysis was used to determine cut‐off values of time from diagnosis to systematic therapy referring to overall survival. Patients were divided into different groups based on the time from diagnosis to systematic therapy and then analyzed for survival.

Results

Of 358 eligible patients with metastatic renal cell carcinoma, 125 (34.9%) had synchronous metastases followed by cytoreductive nephrectomy, and 233 (65.1%) had metachronous metastases. A total of 28 patients received complete metastasectomy. Three optimal cut‐off values for the time from diagnosis to systematic therapy (months) – 1.1, 7.0 and 35.9 – were applied to divide the population into four groups: the synchro group (time from diagnosis to systematic therapy ≤1.0), early group (1.0 < time from diagnosis to systematic therapy ≤ 7.0), intermediate group (7.0 < time from diagnosis to systematic therapy < 36.0) and late group (time from diagnosis to systematic therapy ≥36.0). The targeted therapy‐related overall survival (P < 0.001) and progression‐free survival (P < 0.001) values were significantly different among the four groups. Patients with longer time from diagnosis to systematic therapy had better prognoses and promising efficacy of targeted therapy. With the prolongation of time from diagnosis to systematic therapy, complete metastasectomy was more likely to achieve and bring a better prognosis.

Conclusions

The time from diagnosis to systematic therapy impacts the survival of metastatic renal cell carcinoma patients treated with targeted therapy. The cutoff points of 1, 7 and 36 months were statistically significant. The statistical boundaries might be valuable in future model establishment.

Long-Term Survival Outcomes of Cytoreductive Nephrectomy Combined with Targeted Therapy for Metastatic Renal Cell Carcinoma: A Systematic Review and Individual Patient Data Meta-Analysis

Simple Summary

Cytoreductive nephrectomy (CN) refers to the removal of the primary renal tumor in the setting of metastatic renal cell carcinoma. In the past, the combination of CN with cytokine-based immunotherapy was considered the standard of care. However, CN’s role during the targeted treatment era remains controversial. We attempted to address this issue by performing a systematic review and meta-analysis of the literature. We synthesized data from 15 studies comparing CN and targeted therapy to targeted therapy alone. Our results show that CN combined with targeted therapy was associated with increased survival compared to targeted therapy only. Careful patient selection is required to take full advantage of any survival benefit that CN may offer. Future research endeavors should focus on developing appropriate prognostic models to guide appropriate patient selection for CN.

Abstract

The role of cytoreductive nephrectomy (CN) in the treatment of metastatic renal cell carcinoma (mRCC) remains controversial during the targeted therapy era. To reconcile the current literature, we analyzed the reported survival data at the individual patient level and compared the long-term survival outcomes of CN combined with targeted therapy vs. targeted therapy alone in patients with mRCC. We performed a systematic review of the literature using the MEDLINE, Scopus, and Cochrane Library databases (end-of-search date: 21 July 2020). We recuperated individual patient data from the Kaplan–Meier curves for overall (OS), progression-free (PFS), and cancer-specific survival (CSS) from each study. We subsequently performed one-stage frequentist and Bayesian random-effects meta-analyses using both Cox proportional hazards and restricted mean survival time (RMST) models. Two-stage random-effects meta-analyses were also performed as sensitivity analyses. A subgroup analysis was also performed to determine the effect of CN timing. Fifteen studies fulfilling our inclusion criteria were identified, including fourteen retrospective cohort studies and one randomized controlled trial. In the one-stage frequentist meta-analysis, the CN group had superior OS (hazard ratio [HR]: 0.58, 95% confidence interval [CI]: 0.54–0.62, p < 0.0001) and CSS (HR: 0.63, 95% CI: 0.53–0.75, p < 0.0001). No meaningful clinical difference was observed in PFS (HR: 0.90, 95% CI: 0.80–1.02, p = 0.09). One-stage Bayesian meta-analysis also revealed superior OS (HR: 0.59, 95% credibility interval [CrI]: 0.55–0.63) and CSS (HR: 0.63, 95% CrI: 0.53–0.75) in the CN group, while no meaningful clinical difference was detected in PFS (HR: 0.91, 95% CrI: 0.80–1.02). Similar results were obtained with the RMST models. The OS benefit was also noted in the two-stage meta-analyses models, and in the subgroup of patients who received upfront CN. The combination of CN and targeted therapy for mRCC may lead to superior long-term survival outcomes compared to targeted therapy alone. Careful patient selection based on prognostic factors is required to optimize outcomes.

An evaluation of the role of tumor load in cytoreductive nephrectomy

INTRODUCTION

New radiological tools can accurately provide preoperative three-dimensional spatial assessment of metastatic renal cell carcinoma (RCC). We aimed to determine whether the distribution, volume, shape, and fraction of RCC resected in a cytoreductive nephrectomy associates with survival.

METHODS

We retrospectively reviewed 560 patients undergoing cytoreductive nephrectomy, performing a comprehensive volumetric analysis in eligible patients of all detectable primary and metastatic RCC prior to surgery. We used Cox regression analysis to determine the association between the volume, shape, fraction resected, and distribution of RCC and overall survival (OS).

RESULTS

There were 62 patients eligible for volumetric analysis, with similar baseline characteristics to the entire cohort, and median survivor followup was 34 months. Larger primary tumors were less spherical, but not associated with different metastatic patterns. Increased primary tumor volume and tumor size, but not the fraction of tumor resected, were associated with inferior survival. The rank of tumors based on unidimensional size did not completely correspond to the rank by primary tumor volume, however, both measurements yielded similar concordance for predicted OS. Larger tumor volume was not associated with a longer postoperative time off treatment.

CONCLUSIONS

Primary tumor volume was significant for predicting OS, while the fraction of disease resected did not appear to impact patient outcomes. Although rich in detail, our study is potentially limited by selection bias. Future temporal studies may help elucidate whether the primary tumor shape is associated with tumor growth kinetics.