Stereotactic body radiation therapy in combination with systemic therapy for metastatic renal cell carcinoma: a prospective multicentre study

40 Gray in 5 Fractions for Salvage Reirradiation of Spine Lesions Previously Treated With Stereotactic Body Radiotherapy

BACKGROUND AND PURPOSE

A retrospective single-center analysis of the safety and efficacy of reirradiation to 40 Gy in 5 fractions (reSBRT) in patients previously treated with stereotactic body radiotherapy to the spine was performed.

METHODS

We identified 102 consecutive patients treated with reSBRT for 105 lesions between 3/2013 and 8/2021. Sixty-three patients (61.8%) were treated to the same vertebral level, and 39 (38.2%) to overlapping immediately adjacent levels. Local control was defined as the absence of progression within the treated target volume. The probability of local progression was estimated using a cumulative incidence curve. Death without local progression was considered a competing risk.

RESULTS

Most patients had extensive metastatic disease (54.9%) and were treated to the thoracic spine (53.8%). The most common regimen in the first course of stereotactic body radiotherapy was 27 Gy in 3 fractions, and the median time to reSBRT was 16.4 months. At the time of simulation, 44% of lesions had advanced epidural disease. Accordingly, 80% had myelogram simulations. Both the vertebral body and posterior elements were treated in 86% of lesions. At a median follow-up time of 13.2 months, local failure occurred in 10 lesions (9.5%). The 6- and 12-month cumulative incidences of local failure were 4.8% and 6%, respectively. Seven patients developed radiation-related neuropathy, and 1 patient developed myelopathy. The vertebral compression fracture rate was 16.7%.

CONCLUSION

In patients with extensive disease involvement, reSBRT of spine metastases with 40 Gy in 5 fractions seems to be safe and effective. Prospective trials are needed to determine the optimal dose and fractionation in this clinical scenario.

A new approach to combined proton-photon therapy for metastatic cancer patients

Objective.Proton therapy is a limited resource and is typically not available to metastatic cancer patients. Combined proton-photon therapy (CPPT), where most fractions are delivered with photons and only few with protons, represents an approach to distribute proton resources over a larger patient population. In this study, we consider stereotactic radiotherapy of multiple brain or liver metastases, and develop an approach to optimally take advantage of a single proton fraction by optimizing the proton and photon dose contributions to each individual metastasis.Approach.CPPT treatments must balance two competing goals: (1) deliver a larger dose in the proton fractions to reduce integral dose, and (2) fractionate the dose in the normal tissue between metastases, which requires using the photon fractions. Such CPPT treatments are generated by simultaneously optimizing intensity modulated proton therapy (IMPT) and intensity modulated radiotherapy (IMRT) plans based on their cumulative biologically effective dose (BEDα/β). The dose contributions of the proton and photon fractions to each individual metastasis are handled as additional optimization variables in the optimization problem. The method is demonstrated for two patients with 29 and 30 brain metastases, and two patients with 4 and 3 liver metastases.Main results.Optimized CPPT plans increase the proton dose contribution to most of the metastases, while using photons to fractionate the dose around metastases which are large or located close to critical structures. On average, the optimized CPPT plans reduce the mean brain BED2by 29% and the mean liver BED4by 42% compared to IMRT-only plans. Thereby, the CPPT plans approach the dosimetric quality of IMPT-only plans, for which the mean brain BED2and mean liver BED4are reduced by 28% and 58%, respectively, compared to IMRT-only plans.Significance.CPPT with optimized proton and photon dose contributions to individual metastases may benefit selected metastatic cancer patients without tying up major proton resources.

Management of Renal Cell Carcinoma With Supradiaphragmatic Inferior Vena Cava Thrombus Diagnosed During Acute COVID-19 Infection

Renal cell carcinoma (RCC) tends to undergo intravascular tumor growth along the renal vein, forming tumor thrombi that may extend into the inferior vena cava (IVC) or even the right atrium (Level IV). Managing such cases requires a multidisciplinary approach, especially in patients with acute coronavirus disease 2019 (COVID-19) infection, who face increased risks from surgical interventions. We present a case of RCC with Level IV thrombus and concurrent COVID-19 managed with systemic therapy. We also summarize current literature on treating RCC with IVC thrombus and COVID-19's impact on prognosis. The patient was a 70-year-old female with incidental detection of a 9-cm right heterogeneous renal mass with a supradiaphragmatic tumor thrombus during COVID-19 infection. Due to ongoing pulmonary symptoms, systemic therapy with a combination of ipilimumab and nivolumab was initiated. After an excellent initial response, the patient continued systemic therapy, maintaining a necrotic response in the renal mass and tumor thrombus. The patient continues to tolerate systemic therapy well. We report a rare case of RCC with Level IV tumor thrombus and synchronous acute COVID-19 infection. Our report depicts successful management utilizing systemic therapy with a combination of ipilimumab and nivolumab. The management of such cases necessitates a comprehensive, multidisciplinary approach, considering the risks associated with surgery in the context of recent COVID-19 infection. The case presentation and ensuing literature discussion of the dynamic landscape of RCC management highlights the need for more research to improve treatment plans and guide clinicians in handling such complex situations.

SABR for oligometastatic renal cell carcinoma

Stereotactic ablative body radiotherapy (SABR) aims to accurately deliver a higher than conventional dose of radiotherapy to a well-defined target tumour incorporating advanced immobilisation and imaging techniques. SABR is an emerging treatment option for primary kidney cancer especially when surgery is contraindicated. Increasingly, SABR is being incorporated into the management of low-volume stage IV kidney cancers to delay the need for systemic therapy or to prolong the duration of ongoing systemic treatment. This review will evaluate the evidence and limitations of SABR for oligometastatic renal cell carcinoma.

Incorporating Stereotactic Ablative Radiotherapy into the Multidisciplinary Management of Renal Cell Carcinoma

Stereotactic ablative radiotherapy (SABR) has challenged the conventional wisdom surrounding the radioresistance of renal cell carcinoma (RCC). In the past decade, there has been a significant accumulation of clinical data to support the safety and efficacy of SABR in RCC. Herein, we review the use of SABR across the spectrum of RCC. We performed an online search of the Pubmed database from January 1990 through April 2023. Studies of SABR/stereotactic radiosurgery targeting primary, extracranial, and intracranial metastatic RCC were included. For SABR in non-metastatic RCC, this includes its use in small renal masses, larger renal masses, and inferior vena cava tumor thrombi. In the metastatic setting, SABR can be used at diagnosis, for oligometastatic and oligoprogressive disease, and for symptomatic reasons. Notably, SABR can be used for both the primary renal tumor and metastasis-directed therapy. Management of RCC is evolving rapidly, and the role that SABR will have in this landscape is being assessed in a number of ongoing prospective clinical trials. The objective of this narrative review is to summarize the evidence corroborating the use of SABR in RCC.

Beyond the Knife in Renal Cell Carcinoma: A Systematic Review-To Ablate or Not to Ablate?

Intensified systemic therapy in metastatic renal cell carcinoma (mRCC) has led to improved patient outcomes. Patients commonly require local control of one or a few metastases. The aim was to evaluate metastasis-directed ablative therapies in extracranial mRCC. Two databases and one registry were searched, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach, for all prospective and matched-pair case-control mRCC studies of radiofrequency ablation (RFA), cryotherapy, microwave ablation (MWA), and stereotactic body radiotherapy (SBRT). Eighteen studies were identified. Fourteen investigated SBRT in 424 patients. Four thermal ablation studies were identified: two cryotherapy (56 patients) and two RFA studies (90 patients). The median participant number was 30 (range 12-69). The combined median follow-up was 17.3 months (range 8-52). Four SBRT studies reported local control (LC) at 12 months, median 84.4% (range 82.5-93). Seven studies (six SBRT and one cryotherapy) reported an LC rate of median 87% (79-100%). Median overall survival (OS) was reported in eight studies (five SBRT, two cryotherapy, and one RFA) with a median of 22.7 months (range 6.7-not reached). Median progression-free survival was reported in seven studies (five SBRT, one cryotherapy, and one RFA); the median was 9.3 months (range 3.0-22.7 months). Grade ≥ 3 toxicity ranged from 1.7% to 10%. SBRT has excellent local control outcomes and acceptable toxicity. Only four eligible thermal ablative studies were identified and could not be compared with SBRT. Translationally rich definitive studies are warranted.

Metastases-directed stereotactic body radiotherapy in combination with targeted therapy or immunotherapy: systematic review and consensus recommendations by the EORTC-ESTRO OligoCare consortium

Stereotactic body radiotherapy (SBRT) for patients with metastatic cancer, especially when characterised by a low tumour burden (ie, oligometastatic disease), receiving targeted therapy or immunotherapy has become a frequently practised and guideline-supported treatment strategy. Despite the increasing use in routine clinical practice, there is little information on the safety of combining SBRT with modern targeted therapy or immunotherapy and a paucity of high-level evidence to guide clinical management. A systematic literature review was performed to identify the toxicity profiles of combined metastases-directed SBRT and targeted therapy or immunotherapy. These results served as the basis for an international Delphi consensus process among 28 interdisciplinary experts who are members of the European Society for Radiotherapy and Oncology (ESTRO) and European Organisation for Research and Treatment of Cancer (EORTC) OligoCare consortium. Consensus was sought about risk mitigation strategies of metastases-directed SBRT combined with targeted therapy or immunotherapy; a potential need for and length of interruption to targeted therapy or immunotherapy around SBRT delivery; and potential adaptations of radiation dose and fractionation. Results of this systematic review and consensus process compile the best available evidence for safe combination of metastases-directed SBRT and targeted therapy or immunotherapy for patients with metastatic or oligometastatic cancer and aim to guide today's clinical practice and the design of future clinical trials.

On target methods to induce abscopal phenomenon for Off-Target effects: From happenstance to happenings

Although the "abscopal phenomenon" has been described several decades ago, this phenomenon lately has been obtaining momentous traction with the dawn of immune-based therapies. There has been increased cross talk among radiation oncologists, oncologists and immunologists and consequently a surge in the number of prospective clinical trials. This must be coupled with translation work from these clinical trials to aid in eventual identification of patients who may benefit. Abscopal effects may be induced by local and systemic methods, conventional radiotherapy, particle radiation, radionucleotide methods, cryoablation and brachytherapy. These approaches have all been reported to be stimulate abscopal effect. Immune induction by immune checkpoint therapy, immune adjuvants, cellular therapy including CAR and NK cell therapies may generate systemic abscopal response. With increasing recognition of this effect, there remains a lot of work to explore the modalities of inducing abscopal responses and ultimate prediction or prognostication on stratifying who may benefit. Ultimately, there is an urgent need for prospective studies and data to tease apart which one of these modalities can be applied to the appropriate candidate, to the appropriate cancer at the appropriate setting. This review seeks to elucidate readers on the different modalities of radiation, systemic therapies and other techniques rarely explored to potentiate the abscopal effect from a mere coincidence to a finite occurrence.

Stereotactic body radiation therapy for kidney cancer. Where do we stand?

At present, surgery is still the gold standard for the local treatment of renal cancer. Nonetheless, in several clinical scenarios, stereotactic body radiation therapy (SBRT) also known as stereotactic ablative body radiotherapy (SABR) is emerging as a highly effective ablative technique in fragile patients and those with significant comorbidities, as well as in cases where percutaneous therapy (cryoablation or radiofrequency) is not viable. However, considering the intrinsic radioresistance of renal tumors, the optimal treatment schemes have not been established. In oligometastatic patients, it has been reported that the control of the oligometastases can be a potentially curable approach. Being a technique than can be administered exclusively or in combination with systemic therapy, treatment individualization based on patient characteristics is key. Another scenario under investigation is oligoprogression, where SBRT offers the possibility of delaying further lines of systemic therapy by eliminating subclones of resistant tumor with ablative doses, with the additional opportunity of stimulating the immune system (immunomodulatory role). In this review, we have conducted an analysis of recently published studies that test the role of this technique in different clinical scenarios of this disease. We have found promising results that make SBRT a potent therapeutic approach with low toxicity. We also comment on ongoing studies that will generate the necessary evidence needed for the implementation of this technique in our daily clinical practice.

The Emerging Role of Extracranial Stereotactic Ablative Radiotherapy for Metastatic Renal Cell Carcinoma: A Systematic Review

CONTEXT

Although the management of metastatic renal cell carcinoma (mRCC) has been revolutionized by the advent of new systemic agents, still few patients experience a long-term durable response. Stereotactic ablative radiotherapy (SABR) is nowadays commonly used as metastasis-directed therapy (MDT), but limited data exist on how best to implement this strategy as part of a multimodal approach.

OBJECTIVE

To evaluate the potential role of extracranial SABR in mRCC and to identify future therapeutic developments of SABR in different disease settings.

EVIDENCE ACQUISITION

A systematic review was conducted in May 2022 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement on the PubMed database. Thirty-four studies were selected for inclusion in this systematic review.

EVIDENCE SYNTHESIS

SABR has been used with four main goals: (1) eradication of the whole metastatic burden in synchronous and metachronous oligometastatic patients, resulting in a long-term local control (LC) rate of >90% and median progression-free survival (PFS) ranging between 8 and 15 mo; (2) eradication of oligoprogressive lesions, enabling an extension of the duration of the systemic therapy by approximately 9 mo; (3) improvement of the response to systemic therapy in polymetastatic patients, resulting in an overall response rate ranging from 17% to 56%; and (4) cytoreduction in polymetastatic mRCC patients, with LC rates ranging between 71% and 100%, and preservation of the renal function, but unclear PFS and overall survival impact. Overall, the combination of SABR and systemic agents has been associated with overall good tolerance, with grade ≥3 toxicity ranging from 0% to 13%.

CONCLUSIONS

Current data highlight the role of SABR as an emerging MDT treatment option in both oligometastatic and oligoprogressive extracranial mRCC, able to ensure long-term disease control and delay the use of next-line systemic therapies. The use of SABR for cytoreduction in the de novo metastatic disease and as an immunological booster in the polymetastatic setting remains investigational and warrants further investigations.

PATIENT SUMMARY

Radiotherapy delivered with ablative doses (>6 Gy per fraction) is a promising treatment strategy for patients diagnosed with metastatic renal cell carcinoma. Excellent outcome results have been observed in patients with a limited number of metastases, improving metastasis-free survival by several months. For patients with a few metastases progressing under systemic therapy, radiotherapy allows an extension of the duration of the ongoing therapy by several months.

Stereotactic Ablative Radiation for Systemic Therapy-naïve Oligometastatic Kidney Cancer

BACKGROUND

Evidence-based guidelines for the management of systemic therapy-naïve oligometastatic renal cell carcinoma (RCC) are lacking.

OBJECTIVE

To evaluate the potential of stereotactic ablative radiotherapy (SAbR) to provide longitudinal disease control while preserving quality of life (QOL) in patients with systemic therapy-naïve oligometastatic RCC.

DESIGN, SETTING, AND PARTICIPANTS

RCC patients with three or fewer extracranial metastases were eligible. SAbR was administered longitudinally to all upfront and, as applicable, subsequent metastases.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

This prospective phase II single-arm trial was powered to achieve a primary objective of freedom from systemic therapy for >1 yr in >60% of patients (using the Clopper and Pearson methodology). Secondary endpoints included progression-free survival (PFS), defined as the time from first SAbR to progression not amenable to SAbR (local failure at SAbR-treated sites, new metastases not amenable to SAbR, more than three new metastases, or brain metastases); patient-reported QOL metrics; local control (LC) rates; toxicity; cancer-specific survival (CSS); and overall survival (OS).

RESULTS AND LIMITATIONS

Twenty-three patients received SAbR to 33 initial and 57 total sites. The median follow-up was 21.7 mo (interquartile range 16.3-30.3). Exceeding the prespecified 60% benchmark, freedom from systemic therapy at 1 yr was 91.3% (95% confidence interval [CI]: 69.5, 97.8). One-year PFS was 82.6% (95% CI: 60.1, 93.1). QOL was largely unaffected. LC was 100%. There were no grade 3/4 toxicities, but there was one death due to immune-related colitis 3 mo after SAbR while on subsequent checkpoint inhibitor therapy, where a SAbR contribution could not be excluded. One-year OS was 95.7% (95% CI: 72.9, 99.4); one-year CSS was 100%.

CONCLUSIONS

SAbR for oligometastatic RCC was associated with meaningful longitudinal disease control while preserving QOL. These data support further evaluation of SAbR for systemic therapy-naïve oligometastatic RCC.

PATIENT SUMMARY

Sequential stereotactic radiation therapy can safely and effectively control metastatic kidney cancer with limited spread for over a year without compromising patients' quality of life.

Combination of radiation and immunotherapy in the treatment of genitourinary malignancies: A systematic review and meta-analysis

BACKGROUND

Due to possible synergistic effects, the combination of radiation therapy (RT) and immune checkpoint inhibitors (ICI) represents an interesting therapeutic option. An increasing number of clinical trials are ongoing to investigate this combination in genitourinary malignancies and the first results are available.

OBJECTIVES

To review and summarize available data on the combination of RT and ICI in genitourinary malignancies and update the evidence for this potential therapeutic approach.

EVIDENCE ACQUISITION

A study protocol was registered in the PROSPERO-Database. Terms of search were prostate cancer, bladder cancer, renal cell carcinoma, penile cancer, testicular cancer, radiotherapy, and immunotherapy in multiple literature databases and study registers. Clinical studies reporting on the combination treatment of RT and ICI were included. A systematic review of ongoing trials according to the PRISMA statement and a meta-analysis of available trials were performed.

EVIDENCE SYNTHESIS

Overall, 43 studies met the inclusion criteria examining the therapeutic effect of combined RT and ICI. For bladder cancer, renal cell carcinoma, prostate cancer, and penile cancer 28, 9, 5, and 1 trial could be identified, respectively. No study was found for testicular cancer. Three phases III trials were identified, all other trials were phase I or II. Twelve studies have been completed so far. The meta-analysis of available data indicates comparable toxicity of RT plus ICI vs. ICI alone for grade 3/4 AEs. Mature efficacy data is limited with interesting early results.

CONCLUSION

This article reviews the clinical trial landscape investigating RT and ICI in genitourinary malignancies. It provides an overview of ongoing trials and discusses available results. Actual data regarding efficacy is limited, while toxicities seem comparable to ICI alone. Especially in bladder and kidney cancer, further trial results might impact on the clinical use of the combination therapy.

The Role of Stereotactic Ablative Body Radiotherapy in Renal Cell Carcinoma

CONTEXT

Stereotactic ablative body radiotherapy (SABR) is an emerging treatment modality for primary and metastatic renal cell carcinoma (RCC).

OBJECTIVE

To review and summarise the evidence on the use of SABR in RCC in a narrative review.

EVIDENCE ACQUISITION

We performed an online search of the PubMed database from January 2000 through December 2021. Studies of SABR/stereotactic radiosurgery (SRS) targeting primary, extracranial, or intracranial metastatic RCC were included.

EVIDENCE SYNTHESIS

Two meta-analyses (including 54 studies), and 13 prospective and 20 retrospective studies were included in this review. In aggregate, SABR for 589 primary RCCs in 575 patients resulted in a local control rate of above 90% with grade 3-4 toxicity of 0-9%. Similarly, the local control rate ranged between 90% and 97% with SRS in 1225 patients with intracranial metastatic RCC. SABR was able to delay systemic therapy for at least 1 yr in 70-90% of oligometastatic RCC patients with grade 3-4 toxicity of <10%. As per the early data, the combination of SABR with systemic therapy for metastatic RCC, such as targeted therapy or immunotherapy, appears safe, feasible, and tolerable.

CONCLUSIONS

We outlined data supporting SABR in the key clinical scenarios of primary and metastatic, including oligometastatic, RCC in lieu of systemic therapy, in combination with systemic therapy, and palliation of brain and spinal metastases.

PATIENT SUMMARY

Stereotactic ablative body radiotherapy (SABR) is a relatively new treatment option in kidney cancer. Here, we review the published literature on the experience of using SABR in kidney cancer. The accumulated evidence demonstrates that SABR can be used safely and effectively to treat selected cases of primary or secondary kidney cancer.

Outcomes of Radiation Therapy Plus Immunotherapy in Metastatic Renal Cell Carcinoma: Results From the Canadian Kidney Cancer Information System

Purpose

With the integration of immunotherapy (IO) agents in the management of metastatic renal cell carcinoma (mRCC), there has been interest in the combined use with radiation therapy (RT). However, real world data are limited. The purpose of this study was to evaluate outcomes in patients with mRCC receiving both RT and IO compared with IO alone.

Methods and Materials

Data were collected from Canadian Kidney Cancer Information System from January 2011 to September 2019 across 14 academic centers. Patients with mRCC who received IO as first- or second-line therapy were included. RT was categorized as radical dose or palliative dose. Kaplan-Meier estimates were reported for overall survival (OS) and time to treatment failure. Cox proportional hazard models were used adjusted for age and International Metastatic RCC Database Consortium risk categories.

Results

In total, 505 patients were included in the study: 179 received RT + IO and 326 received IO alone. Two-year OS for the RT + IO group was 55.0% compared with 66.4% in the IO alone cohort (adjusted hazard ratio [aHR], 1.38; P = .07). At 2 years, 12.2% of the RT + IO patients remained on therapy versus 30.9% in the IO alone group (aHR, 1.30; P = .02). For patients receiving first-line therapy, 2-year OS in the RT + IO group was 56.4% versus 78.4% in the IO alone arm, though this difference was not statistically significant (aHR, 1.23; P = .56). For patients receiving radical dose and palliative dose, 2-year OS was 57.0% and 53.9%, respectively (aHR, 0.86; P = .63).

Conclusions

In this descriptive analysis, more than one-third of patients with mRCC received RT and demonstrated inferior outcomes compared with IO alone. Potential explanations include greater presence of adverse metastatic sites in those receiving RT. Prospective clinical trials evaluating potential benefits of RT in an IO era remain an important need.

Phase II Trial of Stereotactic Ablative Radiation for Oligoprogressive Metastatic Kidney Cancer

BACKGROUND

Patients with metastatic renal cell carcinoma (mRCC) treated with systemic therapy sometimes progress at limited sites.The best treatment approach for patients with oligoprogression remains unclear.

OBJECTIVE

To determine the ability of stereotactic ablative radiation (SAbR) to extend ongoing systemic therapy in mRCC patients with oligoprogression.

DESIGN, SETTING, AND PARTICIPANTS

A single-arm phase II clinical trial was conducted at a university medical center and county hospital, including 20 patients with mRCC on first- to fourth-line systemic therapy with three or fewer sites of progression (including new sites) involving ≤30% of all sites.

INTERVENTION

SAbR to oligoprogressing metastases at outset and longitudinally, while radiated sites remain controlled and overall disease oligoprogressive.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary objective was to extend ongoing systemic therapy by >6 mo in >40% of patients. Secondary endpoints included overall survival, toxicity, and patient-reported quality of life.

RESULTS AND LIMITATIONS

Twenty patients were enrolled. Upfront and sequential SAbR was administered to a total of 37 sites. The local control rate was 100%. At a median follow-up of 10.4 mo (interquartile range: 5.8-16.4), SAbR extended the duration of the ongoing systemic therapy by >6 mo in 14 patients (70%, 95% confidence interval [CI]: 49.9-90.1). The median time from SAbR to the onset of new systemic therapy or death was 11.1 mo (95% CI: 4.5-19.3). The median duration of SAbR-aided systemic therapy was 24.4 mo (95% CI: 15.3-42.2). Median overall survival was not reached. One patient developed grade 3 gastrointestinal toxicity possibly related to treatment. There was no significant decline in quality of life. Limitations include nonrandomized design and a small patient cohort.

CONCLUSIONS

SAbR extended the duration of the ongoing systemic therapy for patients with oligoprogressive mRCC without undermining quality of life. These data support the evaluation of SAbR for oligoprogressive mRCC in a prospective randomized clinical trial.

PATIENT SUMMARY

Patients with metastatic kidney cancer on systemic therapy but progressing at limited sites may benefit from focused radiation to progressive sites. Focused radiation was safe and effective, and extended the duration of the ongoing systemic therapy.

The role of stereotactic body radiation therapy and its integration with systemic therapies in metastatic kidney cancer: a multicenter study on behalf of the AIRO (Italian Association of Radiotherapy and Clinical Oncology) genitourinary study group

Although systemic therapy represents the standard of care for polymetastatic kidney cancer, stereotactic body radiation therapy (SBRT) may play a relevant role in the oligometastatic setting. We conducted a multicenter study including oligometastatic kidney cancer treated with SBRT. We retrospectively analyzed 207 patients who underwent 245 SBRT treatments on 385 lesions, including 165 (42.9%) oligorecurrent (OR) and 220 (57.1%) oligoprogressive (OP) lesions. Most common sites were lung (30.9%) for OR group, and bone (32.7%) for OP group. Among 78 (31.8%) patients receiving concomitant systemic therapy, sunitinib (61.5%) and pazopanib (15.4%) were the most common for OR patients, while sunitinib (49.2%) and nivolumab (20.0%) for OP patients. End points were local control (LC), progression free survival (PFS), overall survival (OS), time to next systemic therapy (TTNS) and toxicity. Median follow-up was 18.6 months. 1, 2 and 3-year LC rates were 89.4%, 80.1% and 76.6% in OR patients, and 82.7%, 76.9% and 64.3% in those with OP, respectively. LC for OP group was influenced by clear cell histology (p = 0.000), total number of lesions (p = 0.004), systemic therapy during SBRT (p = 0.012), and SBRT dose (p = 0.012). Median PFS was 37.9 months. 1, 2- and 3-year OS was 92.7%, 86.4% and 81.8%, respectively. Median TTNS was 15.8 months for OR patients, and 13.9 months for OP patients. No grade 3 or higher toxicities were reported for both groups. SBRT may be considered an effective safe option in the multidisciplinary management of both OR and OP metastases from kidney cancer.

Stereotactic body radiotherapy in combination with non-frontline PD-1 inhibitors and targeted agents in metastatic renal cell carcinoma

BACKGROUND

Radiotherapy may work synergistically with immunotherapy and targeted agents. We aimed to assess the safety and outcomes of stereotactic body radiotherapy (SBRT) plus non-first-line programmed death-1 (PD-1) inhibitors and targeted agents (TA) in metastatic renal cell carcinoma (mRCC).

METHODS

We retrospectively reviewed 74 patients treated with non-first-line PD-1 inhibitors plus TA in non-first-line setting. Survival outcomes were calculated from the anti-PD-1 treatment using the Kaplan-Meier method. Univariate and multivariate analyses were performed by Cox proportional hazards models.

RESULTS

Thirty-two (43.2%) patients received anti-PD-1/TA therapy alone (anti-PD-1/TA alone group), and 42 (56.8%) received SBRT in addition (anti-PD-1/TA + SBRT group). The median duration of first-line therapy was 8.6 months. Patients in the anti-PD-1/TA + SBRT group had significantly longer overall survival (OS) (38.5 vs 15.4 months; P = 0.022). On multivariate analysis, oligometastasis, ECOG performance status 0-1, anti-PD-1/TA + SBRT, and duration of first-line therapy ≥ 8.6 months were predictors for OS. The addition of SBRT was associated with improved OS in patients with clear-cell type (HR 0.19; 95% CI 0.07-0.55; P = 0.002) and duration of first-line therapy ≥ 8.6 months (HR 0.22; 95% CI 0.06-0.88; P = 0.032). Grade ≥ 3 toxicities occurred in 23 patients (54.8%) in the anti-PD-1/TA + SBRT group, and in 21 patients (65.6%) in the anti-PD-1/TA alone group.

CONCLUSIONS

Incorporating SBRT into anti-PD-1/TA therapy is safe and tolerable. Further investigation is needed, particularly in patients with clear-cell histology and a longer duration of response to first-line antiangiogenic therapy.

Stereotactic Body Radiotherapy in Contralateral Kidney Oligometastasis From Renal Cell Carcinoma in a Nephrectomized Patient

Background: Renal cell carcinoma (RCC) frequently metastasizes to distal organs such as the lungs, abdomen, bones, and brain. Although rare cases of adrenal gland metastasis from RCC have been described, to our knowledge, no cases have reported the use of stereotactic body radiotherapy (SBRT) in contralateral kidney oligometastasis in a nephrectomized patient with RCC.

Case Report: We report a rare case of single contralateral renal metastasis from RCC in a 65-year-old female that occurred 1 year after right radical nephrectomy. At diagnosis of relapse, the patient received targeted therapy with sunitinib for 9 consecutive months, resulting in a partial regression of renal metastasis. To preserve the organ and consolidate response, SBRT was administered to the residual mass. Targeted therapy was temporarily discontinued 15 days before and after SBRT. Total SBRT dose was 40 Gy in 5 daily fractions given with volumetric modulated arc and image-guided technique. Three months later, magnetic resonance imaging documented a complete regression of disease, a result that persisted at the last follow-up 19 months after SBRT.

Conclusion: The combination of sequential targeted therapy and SBRT provided an excellent outcome in a patient with a solitary kidney who experienced contralateral kidney metastasis from RCC. This treatment approach was well tolerated and controlled the disease.

Efficacy and safety of tyrosine kinase inhibitors alone or in combination with radiation therapy for metastatic renal cell carcinoma: A protocol for evidence-based systematic review and Bayesian network meta-analysis

BACKGROUND

Given the lack of evidence for survival benefit in patients with metastatic renal cell carcinoma from the addition of radiation therapy to tyrosine kinase inhibitor therapy, this Bayesian network meta-analysis aimed to evaluate survival outcomes in patients receiving radiation therapy plus tyrosine kinase inhibitor therapy.

METHODS

The preferred reporting items for systematic reviews and meta-analyses reporting guidelines were followed to conduct this study. The electronic databases of PubMed, Cochrane Library, EMBASE, and Web of Science were searched from the inception to August 2021. All phase III clinical trials that reported the outcomes of tyrosine kinase inhibitor with radiation therapy compared with those of tyrosine kinase inhibitor or radiation therapy alone for patients with metastatic renal cell carcinoma were considered eligible for inclusion in this meta-analysis. Overall survival as the primary outcome of interest, and adverse events as secondary outcome of interest were recorded for meta-analysis.

RESULTS

A Bayesian network meta-analysis is an appropriate statistical method to compare all treatment options by statistically simulating the estimated results of a comprehensive trial, and to compare treatments by common and associated comparators. In addition, Bayesian network meta-analysis can produce ranking probabilities of treatments, which may contribute to clinicians' clinical decision-making.

Nivolumab: 5 Years Since FDA Approval of the First Checkpoint Inhibitor for Renal Cell Carcinoma

On November 23, 2015, the US Food and Drug Administration (FDA) approved nivolumab for the treatment of metastatic renal cell carcinoma (RCC), thus opening a new era of immunotherapy for this tumor. This review summarizes the 5-year experience of studying and using nivolumab in RCC patients.

Survival After Combining Stereotactic Body Radiation Therapy and Tyrosine Kinase Inhibitors in Patients With Metastatic Renal Cell Carcinoma

Background

Stereotactic body radiation therapy (SBRT) and tyrosine kinase inhibitors (TKIs) are effective treatments for metastatic renal cell carcinoma, but data on combining these two modalities are scarce. We aimed to investigate the survival outcomes of SBRT plus TKIs.

Methods

Data of patients treated with TKIs from December 2007 to June 2019 were collected. Patients received SBRT plus TKIs (TKI + SBRT group) or TKIs alone (TKI alone group). Local control (LC), time to change of systemic therapy (TTS), and overall survival (OS) were assessed.

Results

A total of 190 patients were included, and 85 patients received TKI + SBRT. The 2-year LC rate was 92.8%. The median OS in the TKI + SBRT group was significantly longer than that of the TKI alone group (63.2 vs 29.8 months; P < 0.001). In multivariate analysis, IMDC intermediate (HR 1.96; 95% CI 1.10-3.48; P = 0.022) and poor risk (HR 2.43; 95% CI 1.25-4.75; P = 0.009), oligometastasis (HR 0.41; 95% CI 0.26-0.65; P < 0.001), and the addition of SBRT (HR 0.48; 95% CI 0.31-0.75; P = 0.001) were prognostic factors for OS. Patients with oligometastasis (P = 0.009) and those with IMDC favorable (P = 0.044) or intermediate (P = 0.002) risk had significantly longer OS with TKI + SBRT. The median TTS were 21.5, 6.4, and 9.0 months in patients receiving SBRT before first-line TKI failure, SBRT after first-line TKI failure, and first-line TKI alone (P < 0.001). Five patients (5.9%) experienced SBRT-related grade 3 toxicities.

Conclusions

Combining SBRT with TKIs is tolerable and associated with longer OS in selected patients, such as those with oligometastasis and favorable or intermediate risk.

Stereotactic body radiotherapy (SBRT) in combination with drugs in metastatic kidney cancer: A systematic review

OBJECTIVE

To conduct a systematic review and meta-analysis of the role of SBRTdrug combination in patients affected by mRCC and associated oncologic outcomes and toxicity profiles.

EVIDENCE ACQUISITION

We performed a critical review of the Pubmed, Medline, and Embase databases from January 1, 2000 through April 30, 2020 according to the Preferred Reporting Items and Meta-Analyses statement. To assess the overall quality of the literature reviewed, we used a modified Delphi tool.

EVIDENCE SYNTHESIS

A total of 6 studies were included, corresponding to a cohort of 216 patients. Tyrosine Kinases Inhibitors were the most widely used drugs in combination with SBRT, being administered in 93% patients. No study reported an increase of radiation-induced toxicity.

CONCLUSIONS

SBRT resulted to be safe, without increase in terms of drugs-related adverse events in this setting. Moreover, this approach showed promising clinical outcomes in terms of LC and OS.

Update on First-Line Combination Treatment Approaches in Metastatic Clear-Cell Renal Cell Carcinoma

OPINION STATEMENT

The treatment for metastatic renal cell carcinoma (mRCC) has significantly evolved in recent years with a deeper understanding of the molecular make-up of the disease and the clinical development of therapies with novel mechanisms of action. While some patients with more indolent disease may benefit from local therapy such as metastasectomy or cytoreductive nephrectomy, others may safely embark on an active surveillance program or be offered targeted therapy. Yet, a combination regimen including an ICI is the most effective regimen and should be considered in most mRCC cases. Ongoing studies will help determine which factors can be further used to optimize treatment selection and personalize disease management.

Cytoreductive stereotactic body radiotherapy (SBRT) and combination SBRT with immune checkpoint inhibitors in metastatic renal cell carcinoma

INTRODUCTION

Preclinical evidence demonstrates the immunogenic potential of stereotactic body radiotherapy (SBRT). There is growing interest in investigating this interplay with the immune system in metastatic renal cell carcinoma (mRCC). Cytoreduction with SBRT and combination therapy with SBRT and checkpoint inhibitor immuno-oncology agents (IO) are two potential therapeutic strategies in mRCC. In this review, we summarize the current clinical evidence for the use of cytoreductive SBRT to primary kidney and combination SBRT with IO.

METHODS

A literature review for articles and abstracts published between January 2000 and March 2020 was conducted through the PubMed, the American Society of Clinical Oncology (ASCO), and the American Society of Radiation Oncology (ASTRO) databases. Evaluation of studies followed the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) criteria.

RESULTS

A total of three articles for cytoreductive SBRT and one article and three abstracts for combination SBRT and IO in mRCC met inclusion criteria for this review. Evidence for SBRT to primary kidney is limited by small series and pilot studies. Outcomes vary widely due to small patient numbers and study heterogeneity. Local control ranges from 85-100% and one- and two-year overall survival ranges from 38-71% and 19-53%, respectively. Combination SBRT and IO are tolerable for patients with early data, suggesting grade 3-4 adverse event rates of 0-24%. Long-term survival data is not yet available.

CONCLUSIONS

Cytoreductive SBRT and combination SBRT with IO therapy represent promising treatment strategies in mRCC. The evidence for clinical benefit is currently limited and requires further study with well-designed, randomized controlled trials.

Stereotactic radiotherapy combined with immunotherapy or targeted therapy for metastatic renal cell carcinoma

OBJECTIVES

To evaluate the safety and efficacy of stereotactic radiotherapy (SRT) in patients with metastatic renal cell carcinoma (mRCC) concurrently receiving targeted therapy (TT) or immunotherapy.

PATIENTS AND METHODS

Data on patients with mRCC were extracted from a retrospective international multicentre register study (TOaSTT), investigating SRT concurrent (≤30 days) with TT/immune checkpoint inhibitor (ICI) therapy. Overall survival (OS), progression-free survival (PFS), local metastasis control (LC) and time to systemic therapy switch were analysed using Kaplan-Meier curves and log-rank testing. Clinical and treatment factors influencing survival were analysed using multivariate Cox regression. Acute and late SRT-induced toxicity were defined according to the Common Terminology Criteria for Adverse Events v.4.03.

RESULTS

Fifty-three patients who underwent 128 sessions of SRT were included, of whom 58% presented with oligometastatic disease (OMD). ICIs and TT were received by 32% and 68% of patients, respectively. Twenty patients (37%) paused TT for a median (range) of 14 (2-21) days. ICI therapy was not paused in any patient. A median (range) of 1 (1-5) metastatic tumour was treated per patient, with a median (range) SRT dose of 65 (40-129.4) Gy (biologically effective dose). The OS, LC and PFS rates at 1 year were 71%, 75% and 25%, respectively. The median OS and PFS were not significantly different among patients receiving TT vs those receiving ICIs (P = 0.329). New lesions were treated with a repeat radiotherapy course in 46% of patients. After 1 year, 62% of patients remained on the same systemic therapy as at the time of SRT; this was more frequent for ICI therapy compared to TT (83% vs 36%; P = 0.035). OMD was an independent prognostic factor for OS (P = 0.004, 95% confidence interval [CI] 0.035-0.528) and PFS (P = 0.004; 95% CI 0.165-0.717) in multivariate analysis. Eastern Cooperative Oncology Group performance status (ECOG-PS) was the other independent prognostic factor for OS (P = 0.001, 95% CI 0.001-0.351). Acute grade 3 toxicity was observed in two patients, and late grade 3 toxicity in one patient. No grade 4 or 5 toxicity was observed.

CONCLUSION

Combined treatment with TT or immunotherapy and concurrent SRT was safe, without signals of increased severe toxicity. As we observed no signal of excess toxicity, full-dose SRT should be considered to achieve optimal metastasis control in patients receiving TT or immunotherapy. Favourable PFS and OS were observed for patients with oligometastatic RCC with a good ECOG-PS, which should form the basis for prospective testing of this treatment strategy in properly designed clinical trials.

The Reintroduction of Radiotherapy Into the Integrated Management of Kidney Cancer

The incidence of renal cell carcinoma (RCC) has been increasing, with a moderate subgroup of individuals who later develop metastatic disease. Historically, metastatic RCC has been managed with systemic therapy because RCC was believed to be radioresistant. Local therapies, such as stereotactic body radiation therapy, also known as stereotactic ablative radiotherapy, which utilize focused high-dose-rate radiation delivered over a limited number of treatments, have been successful in controlling local disease and, in some cases, extending survival in patients with intracranial and extracranial metastatic RCC. Stereotactic ablative radiotherapy is highly effective in treating intact disease when patients are not surgical candidates. Stereotactic ablative radiotherapy is well tolerated when used in conjunction with systemic therapy such as tyrosine kinase inhibitors and immune checkpoint inhibitors. These successes have prompted investigators to evaluate the efficacy of stereotactic body radiation therapy in novel settings such as neoadjuvant treatment of advanced RCC with tumor thrombus and oligometastatic/oligoprogressive disease states.

Radiation induces dynamic changes to the T cell repertoire in renal cell carcinoma patients

Clinical studies combining radiation and immunotherapy have shown promising response rates, strengthening efforts to sensitize tumors to immune-mediated attack. Thus, there is an ongoing surge in trials using preconditioning regimens with immunotherapy. Yet, due to the scarcity of resected tumors treated in situ with radiotherapy, there has been little investigation of radiation's sole contributions to local and systemic antitumor immunity in patients. Without this access, translational studies have been limited to evaluating circulating immune subsets and systemic remodeling of peripheral T cell receptor repertoires. This constraint has left gaps in how radiation impacts intratumoral responses and whether tumor-resident T cell clones are amplified following treatment. Therefore, to interrogate the immune impact of radiation on the tumor microenvironment and test the hypothesis that radiation initiates local and systemic expansion of tumor-resident clones, we analyzed renal cell carcinomas from patients treated with stereotactic body radiation therapy. Transcriptomic comparisons were evaluated by bulk RNA sequencing. T cell receptor sequencing monitored repertoires during treatment. Pathway analysis showed radiation-specific enrichment of immune-related processes, and T cell receptor sequencing revealed increased clonality in radiation-treated tumors. The frequency of identified, tumor-enriched clonotypes was tracked across serial blood samples. We observed increased abundance of tumor-enriched clonotypes at 2 wk postradiation compared with pretreatment levels; however, this expansion was not sustained, and levels contracted toward baseline by 4 wk posttreatment. Taken together, these results indicate robust intratumoral immune remodeling and a window of tumor-resident T cell expansion following radiation that may be leveraged for the rational design of combinatorial strategies.

Possible abscopal effect after discontinuation of nivolumab in metastatic renal cell carcinoma

INTRODUCTION

Renal cell carcinoma has been considered radioresistant. Recently, several studies have reported the efficacy of combination therapy using radiotherapy and immune checkpoint inhibitors.

CASE PRESENTATION

In 1999, a 56-year-old woman underwent left nephrectomy (clear cell carcinoma, pT1bN0M0). Seventeen years postoperatively, recurrence in the left lung hilum was observed. Despite administration of three molecular target drugs, all treatments were terminated due to adverse events. Nivolumab was initiated in December 2016. In August 2017, subcutaneous and lung metastases were observed. Moreover in January 2018, right renal metastasis was noted. After 22 cycles of nivolumab treatment, metastasis in the iliac bone was observed, and the patient was subjected to conventional palliative external beam radiation therapy. Five months after radiotherapy, there was significant reduction in multiple metastases. Here, we reported the case presenting with possible abscopal effect.

CONCLUSION

Radiotherapy combined with immune checkpoint inhibitors may induce systemic effects against metastatic renal carcinoma.

Abscopal effect after hypofractionated radiotherapy in metastatic renal cell carcinoma pretreated with pazopanib

Background: The abscopal effect consists of distant metastases response after local treatment based on systemic immune stimulation. It is a rare event observed in many tumors, especially with radiotherapy and immunotherapy. Clinical case: We report the long-term abscopal effect in a metastatic renal cell carcinoma patient with lung metastasectomy, after hypofractionated radiotherapy on lymph node metastasis. The patient was pretreated with pazopanib, which was discontinued early owing to toxicity before radiotherapy. Methodology: Immunohistological analyses of the primary tumor and metastases were performed. Discussion: We supposed that radiotherapy, and maybe tyrosine kinase inhibitors, could act as immune-primers for abscopal effect modifying the immune tumor microenvironment. Conclusion: Future studies are needed to optimize the combination of radiotherapy with systemic therapy for better long-term tumor control in selected patients.

Oligometastasis and local ablation in the era of systemic targeted and immunotherapy

Background

During these last years, new agents have dramatically improved the survival of the metastatic patients. Oligometastases represent a continuous field of interest in which the integration of metastases-directed therapy and drugs could further improve the oncologic outcomes.

Herein a narrative review is performed regarding the main rationale in combining immunotherapy and target therapies with SBRT looking at the available clinical data in case of oligometastatic NSCLC, Melanoma and Kidney cancer.

Material and method

Narrative Review regarding retrospective and prospective studies published between January 2009 to November 2019 with at least 20 patients analyzed.

Results

Concerning the combination between SBRT and Immunotherapy, the correct sequence of remains uncertain, and seems to be drug-dependent. The optimal patients’ selection is crucial to expect substantial benefits to SBRT/Immunotherapy combination and, among several factors. A potential field of interest is represented by the so-called oligoprogressed disease, in which SBRT could improve the long-term efficacy of the existing target therapy.

Conclusions

A low tumor burden seems to be the most relevant, thus making the oligometastatic disease represent the ideal setting for the use of combination therapies with immunological drugs.