Locoregional recurrence after nephrectomy for localized renal cell carcinoma: Feasibility and outcomes of different treatment modalities

Renal cancer: signaling pathways and advances in targeted therapies

Renal cancer is a highlyheterogeneous malignancy characterized by rising global incidence and mortalityrates. The complex interplay and dysregulation of multiple signaling pathways,including von Hippel-Lindau (VHL)/hypoxia-inducible factor (HIF), phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR), Hippo-yes-associated protein (YAP), Wnt/ß-catenin, cyclic adenosine monophosphate (cAMP), and hepatocyte growth factor (HGF)/c-Met, contribute to theinitiation and progression of renal cancer. Although surgical resection is thestandard treatment for localized renal cancer, recurrence and metastasiscontinue to pose significant challenges. Advanced renal cancer is associatedwith a poor prognosis, and current therapies, such as targeted agents andimmunotherapies, have limitations. This review presents a comprehensiveoverview of the molecular mechanisms underlying aberrant signaling pathways inrenal cancer, emphasizing their intricate crosstalk and synergisticinteractions. We discuss recent advancements in targeted therapies, includingtyrosine kinase inhibitors, and immunotherapies, such as checkpoint inhibitors.Moreover, we underscore the importance of multiomics approaches and networkanalysis in elucidating the complex regulatory networks governing renal cancerpathogenesis. By integrating cutting-edge research and clinical insights, this review contributesto the development of innovative diagnostic and therapeutic strategies, whichhave the potential to improve risk stratification, precision medicine, andultimately, patient outcomes in renal cancer.

The Landscape of Stereotactic Ablative Radiotherapy (SABR) for Renal Cell Cancer (RCC)

Renal cell cancer (RCC) has traditionally been considered radioresistant. Because of this, conventional radiotherapy (RT) has been predominantly relegated to the palliation of symptomatic metastatic disease. The implementation of stereotactic ablative radiotherapy (SABR) has made it possible to deliver higher ablative doses safely, shifting the renal radioresistance paradigm. SABR has increasingly been adopted into the multidisciplinary framework for the treatment of locally recurrent, oligoprogressive, and oligometastatic disease. Furthermore, there is growing evidence of SABR as a non-invasive definitive therapy in patients with primary RCC who are medically inoperable or who decline surgery, unsuited to invasive ablation (surgery or percutaneous techniques), or at high-risk of requiring post-operative dialysis. Encouraging outcomes have even been reported in cases of solitary kidney or pre-existing chronic disease (poor eGFR), with a high likelihood of preserving renal function. A review of clinical evidence supporting the use of ablative radiotherapy (SABR) in primary, recurrent, and metastatic RCC has been conducted. Given the potential immunogenic effect of the high RT doses, we also explore emerging opportunities to combine SABR with systemic treatments. In addition, we explore future directions and ongoing clinical trials in the evolving landscape of this disease.

A review of stereotactic ablative radiotherapy for nonmetastatic renal cell carcinoma

Renal cell carcinoma (RCC) is an uncommon malignancy whose incidence has been increasing over the past few decades, posing treatment challenges for elderly or infirm patients who are not surgical candidates. Stereotactic ablative radiotherapy (SABR) has emerged as a promising non-invasive treatment modality for RCC. The high dose-per-fraction used in SABR overcomes some of the mechanisms of radioresistance that has hindered the effective treatment of RCC with conventional radiotherapy. For primary RCC, local control rates for SABR exceed 90%, with typically minimal grade 3 or higher toxicities, offering a viable alternative for inoperable patients and those not eligible for or unable to tolerate radiofrequency or cryotherapy ablation. SABR can also be used in patients with a solitary kidney as a strategy for renal preservation to avoid need for dialysis. Given its excellent local control rates, low toxicity and preservation of renal function, SABR offers an attractive alternative to more invasive modalities for treatment of localized RCC.

Locoregional recurrence after nephrectomy for localized renal cell carcinoma: Feasibility and outcomes of different treatment modalities

BACKGROUND

Locoregional recurrence after nephrectomy for localized renal cell carcinoma (RCC) is rare with diverse manifestations. The selection criteria and efficacy of different treatments are unanswered. The objective was to compare different treatment modalities and present data on stereotactic body radiotherapy (SBRT) for recurrent RCC.

MATERIALS AND METHODS

Patients with locoregional recurrence after nephrectomy without distant metastasis were identified from institutional big data intelligence platform between 2001 and 2020. Patients receiving local therapy (surgery or SBRT) or systemic therapy alone (targeted therapy or PD-1 inhibitors) were divided into two groups. Progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier method, Cox regression model. Patients were matched with propensity score matching.

RESULTS

Among 106 patients, 33 (31.1%) received systemic therapy alone and 73 (68.9%) received local therapy. Local therapy was surgery in 34 patients (32.1%) and SBRT in 39 (36.8%) patients. Patients treated with systemic therapy alone had more non-clear cell type (p = 0.044), more advanced T stage (p = 0.006), higher number (p = 0.043) but smaller size of lesions (p = 0.042). Patients receiving local therapy had significantly longer PFS than systemic therapy (19.7 vs. 7.5 months, p = 0.001). After matching, the PFS in the local therapy group remained higher (23.9 vs. 7.5 months, p = 0.001). The 2-year OS of the local therapy group and systemic therapy group was 91.6% and 71.8%, respectively (p = 0.084). Local therapy was associated with better PFS (HR 0.37; p = 0.0003) and OS (HR 0.23; p = 0.002) in multivariate analysis. Grade 2 or higher toxicities related to local therapy occurred in nine patients.

CONCLUSIONS

Local therapy could delay disease progression compared with systemic therapy alone. SBRT is safe and effective for locally recurrent RCC.