Outcomes in a Multi-institutional Cohort of Patients Treated With Intraoperative Radiation Therapy for Advanced or Recurrent Renal Cell Carcinoma

Practice-oriented solutions integrating intraoperative electron irradiation and personalized proton therapy for recurrent or unresectable cancers: Proof of concept and potential for dual FLASH effect

Background

Oligo-recurrent disease has a consolidated evidence of long-term surviving patients due to the use of intense local cancer therapy. The latter combines real-time surgical exploration/resection with high-energy electron beam single dose of irradiation. This results in a very precise radiation dose deposit, which is an essential element of contemporary multidisciplinary individualized oncology.

Methods

Patient candidates to proton therapy were evaluated in Multidisciplinary Tumor Board to consider improved treatment options based on the institutional resources and expertise. Proton therapy was delivered by a synchrotron-based pencil beam scanning technology with energy levels from 70.2 to 228.7 MeV, whereas intraoperative electrons were generated in a miniaturized linear accelerator with dose rates ranging from 22 to 36 Gy/min (at Dmax) and energies from 6 to 12 MeV.

Results

In a period of 24 months, 327 patients were treated with proton therapy: 218 were adults, 97 had recurrent cancer, and 54 required re-irradiation. The specific radiation modalities selected in five cases included an integral strategy to optimize the local disease management by the combination of surgery, intraoperative electron boost, and external pencil beam proton therapy as components of the radiotherapy management. Recurrent cancer was present in four cases (cervix, sarcoma, melanoma, and rectum), and one patient had a primary unresectable locally advanced pancreatic adenocarcinoma. In re-irradiated patients (cervix and rectum), a tentative radical total dose was achieved by integrating beams of electrons (ranging from 10- to 20-Gy single dose) and protons (30 to 54-Gy Relative Biological Effectiveness (RBE), in 10-25 fractions).

Conclusions

Individual case solution strategies combining intraoperative electron radiation therapy and proton therapy for patients with oligo-recurrent or unresectable localized cancer are feasible. The potential of this combination can be clinically explored with electron and proton FLASH beams.

Feasibility and Safety of Intraoperative Radiotherapy with Low Energy X-ray Photon Therapy for Recurrent Gynecological Cancer: A Case Series

Objectives: To evaluate the feasibility and safety of low energy X-ray photon intraoperative radiotherapy (IORT) as an adjuvant therapy for recurrent gynecological cancer.Methods: Medical records of all recurrence gynecological cancer patients who underwent IORT were reviewed. Results: Between January 2018 and December 2021, five women (including cervical cancer (n = 2), endometrial cancer (n = 2), and uterine leiomyosarcoma (n = 1)), who underwent IORT and surgical resection for recurrent gynecologic cancer were reviewed. A median dose of 15.62 Gy (range, 12 to 20 Gy) was used for IORT. Repeated IORT and surgical resection was performed in two women. Three women experienced local recurrence, and three women died during follow-up. The 1-year local control rate was 60%. The 2-year overall survival rate was 30%. There was no Clavien–Dindo classification grade III–V complication. Conclusion: IORT using low energy X-ray photon therapy seems to be feasible and safe as an adjuvant therapy in women who underwent salvage surgery for recurrent gynecologic cancer. However, large-scale prospective studies are needed to confirm our findings and evaluate its efficacy.

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.

A Real-World, Population-Based Retrospective Analysis of Therapeutic Survival for Recurrent Localized Renal Cell Carcinoma After Nephrectomy

We retrospectively analyzed therapeutic strategies and risk factors for overall survival (OS) in disease recurrence following curative nephrectomy for localized renal cell carcinoma (loRCC) using the Korean National Cancer Registry Database. We selected 1295 recurrent loRCC patients who underwent either partial or radical nephrectomy from 2007-2013. Patients were excluded for age <19 years, secondary RCC, multiple primary tumors, other SEER stages except for a localized or regional stage, postoperative recurrence within 3-month, and non-nephrectomized cases. Four therapeutic groups were statistically analyzed for OS and risk factors: surgery (OP, 12.0%), other systemic therapy (OST, 59.5%), radiotherapy (RT, 2.8%), and targeted therapy (TT, 25.8%). The overall mortality rate for recurrent loRCC was 32.5%, including 82.4% for RCC-related deaths. The baseline comparison among groups showed statistical differences for the diagnostic age of cancer and the SEER stage (p<0.05). Multivariate analysis of OS showed significance for the TT (hazard ratio [HR]: 6.27), OST (HR: 7.05), and RT (HR: 7.47) groups compared with the OP group, along with significance for the sex, SEER stage, and the time from nephrectomy to treatment for disease recurrence (p<0.05). The median OS curve showed a significantly better OS in the OP group (54.9 months) compared with the TT, OST, and RT groups (41.7, 42.9, and 38.0 months, respectively; p<0.001). In conclusion, the surgery-treated group had the best OS among the different therapeutic strategies for recurrent loRCC after nephrectomy, and the importance of the time from nephrectomy to secondary treatment was a significant prognostic factor.

Radiotherapy and Renal Cell Carcinoma: A Continuing Saga

Renal cell carcinoma (RCC) is one of the most aggressive malignancies of the genito-urinary tract, having a poor prognosis especially in patients with metastasis. Surgical resection remains the gold standard for localized renal cancer disease, with radiotherapy (RT) receiving much skepticism during the last decades. However, many studies have evaluated the role of RT, and although renal cancer is traditionally considered radio-resistant, technological advances in the RT field with regards to modern linear accelerators, as well as advanced RT techniques have resulted in breakthrough therapeutic outcomes. Additionally, the combination of RT with immune checkpoint inhibitors and targeted agents may maximize the clinical benefit. This review article focuses on the role of RT in the therapeutic management of renal cell carcinoma.

Radiation Therapy for Patients with Advanced Renal Cell Carcinoma

Stereotactic radiosurgery and stereotactic body radiation therapy (SBRT) have led to a resurgence of the use of radiotherapy in the management of advanced renal cell carcinoma (RCC). These techniques provide excellent local control and palliation of metastatic sites of disease with minimal toxicity. Additionally, SBRT to the primary tumor may be efficacious and well tolerated in select patients that are not surgical candidates. Emerging data suggest that SBRT may potentiate the immune response, and current and future study will evaluate if SBRT can improve survival outcomes in patients with metastatic RCC.

Treating the Chameleon: Radiotherapy in the management of Renal Cell Cancer

•

Conventional fractionated radiotherapy (RT) is predominantly used for the palliation of symptomatic metastatic disease.

•

Hypofractionated stereotactic RT is increasingly adopted for the treatment of locally recurrent and oligometastatic disease.

•

High-dose radiation seems to have an immunogenic effect in patients with renal cell cancer.

•

Combinations of ablative RT with immunotherapies are promising approaches that might improve outcomes.

Purpose

To review the role of radiotherapy (RT) in the treatment of renal cell cancer (RCC) in the curative and palliative setting.

Content

Details related to the clinical outcomes of primary, preoperative, postoperative and palliative RT are discussed, along with a presentation of the established role of surgery and systemic therapy. An overview of data derived from mono- and multi-institutional trials is provided.

Conclusion

Radiotherapy has been shown to provide good symptom palliation and local control in RCC depending on the dose that can be delivered. There is emerging data suggesting that with the use of high-precision RT methods the indication spectrum of RT can be exploited covering different clinical situations particularly for unresectable local recurrences and oligometastatic disease.

Systematic Review of the Management of Local Kidney Cancer Relapse

CONTEXT

Management of locally recurrent renal cancer is complex.

OBJECTIVE

In this systematic review we analyse the available literature on the management of local renal cancer recurrence.

EVIDENCE ACQUISITION

A systematic search (PubMed, Web of Science, CINAHL, Clinical Trials, and Scopus) of English literature from 2000 to 2017 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

EVIDENCE SYNTHESIS

The search identified 1838 articles. Of those, 36 were included in the evidence synthesis. The majority of the studies identified were retrospective and not controlled. Local recurrence after thermal ablation (TA) may be managed with repeat TA. Alternatively, salvage nephrectomy is possible. However, a higher rate of complications should be expected than after primary nephrectomy. Salvage nephrectomy and TA represent treatment options for local recurrence after partial nephrectomy. Local retroperitoneal recurrence after radical nephrectomy is ideally treated with surgical resection, for which minimally invasive approaches might be applicable to select patients. For large recurrences, addition of intraoperative radiation may improve local control. Local tumour destruction appears to be more beneficial than systemic therapy alone for local recurrences.

CONCLUSIONS

Management of local renal cancer relapse varies according to the clinical course and prior treatments. The available data are mainly limited to noncontrolled retrospective series. After nephron-sparing treatment, TA represents an effective treatment with low morbidity. For local recurrence after radical nephrectomy, the low-level evidence available suggests superiority of surgical excision relative to systemic therapy or best supportive care. As a consequence, surgery should be prioritised when feasible and applicable.

PATIENT SUMMARY

In renal cell cancer, the occurrence and management of local recurrence depend on the initial treatment. This cancer is a disease with a highly variable clinical course. After initial organ-sparing treatment, thermal ablation offers good cancer control and low rates of complications. For recurrence after radical nephrectomy, surgical excision seems to provide the best long-term cancer control and it is superior to medical therapy alone.

Role of metastasis-directed treatment in kidney cancer

Despite the rapid elaboration of multiple, novel systemic agents introduced for metastatic renal cell carcinoma (mRCC) in recent years, a durable complete response remains elusive with systemic therapy alone. Definitive treatment of the metastatic deposit remains the sole potentially curative option and is a cornerstone of mRCC therapy, offering potential for both local control and palliation of tumor-related symptoms. In this review, the evidence supporting the definitive treatment of mRCC is examined and summarized, including the use of surgical metastasectomy, thermal ablation, radiotherapy, and other minimally invasive options. Multimodal approaches, including the combination of metastasectomy with novel systemic agents, are discussed. Finally, the authors review considerations for patient selection for this type of therapy and summarize available risk-stratification tools that may help guide shared decision making.

Intraoperative radiotherapy: review of techniques and results

Intraoperative radiotherapy (IORT) is a technique that involves precise delivery of a large dose of ionising radiation to the tumour or tumour bed during surgery. Direct visualisation of the tumour bed and ability to space out the normal tissues from the tumour bed allows maximisation of the dose to the tumour while minimising the dose to normal tissues. This results in an improved therapeutic ratio with IORT. Although it was introduced in the 1960s, it has seen a resurgence of popularity with the introduction of self-shielding mobile linear accelerators and low-kV IORT devices, which by eliminating the logistical issues of transport of the patient during surgery for radiotherapy or building a shielded operating room, has enabled its wider use in the community.

Electrons, low-kV X-rays and HDR brachytherapy are all different methods of IORT in current clinical use. Each method has its own unique set of advantages and disadvantages, its own set of indications where one may be better suited than the other, and each requires a specific kind of expertise.

IORT has demonstrated its efficacy in a wide variety of intra-abdominal tumours, recurrent colorectal cancers, recurrent gynaecological cancers, and soft-tissue tumours. Recently, it has emerged as an attractive treatment option for selected, early-stage breast cancer, owing to the ability to complete the entire course of radiotherapy during surgery. IORT has been used in a multitude of roles across these sites, for dose escalation (retroperitoneal sarcoma), EBRT dose de-escalation (paediatric tumours), as sole radiation modality (early breast cancers) and as a re-irradiation modality (recurrent rectal and gynaecological cancers).

This article aims to provide a review of the rationale, techniques, and outcomes for IORT across different sites relevant to current clinical practice.

Radiotherapy for renal cell carcinoma: renaissance of an overlooked approach

Conventional radiotherapy previously had a limited role in the definitive treatment of renal cell carcinoma (RCC), owing to the disappointing outcomes of several trials and the perceived radioresistance of this type of cancer. In this context, radiotherapy has been relegated largely to the palliation of symptoms in patients with metastatic disease, with variable rates of response. Following the availability of newer technologies that enable safe delivery of high-dose radiotherapy, stereotactic ablative radiotherapy (SABR) has become increasingly used in patients with RCC. Preclinical evidence demonstrates that RCC cells are sensitive to ablative doses of radiotherapy (≥8-10 Gy). Trials in the setting of intracranial and extracranial oligometastases, as well as primary RCC, have demonstrated excellent tumour control using this approach. Additionally, an awareness of the capacity of high-dose radiation to stimulate antitumour immunity has resulted in novel combinations of SABR with immunotherapies. Here we describe the historical application of conventional radiotherapy, the current biological understanding of the effects of radiation, and the clinical evidence supporting the use of ablative radiotherapy in RCC. We also explore emerging opportunities to combine systemic targeted agents or immunotherapies with radiation. Radiotherapy, although once an overlooked approach, is moving towards the forefront of RCC treatment.

Role of Radiotherapy in the Treatment of Renal Cell Cancer: Updated and Critical Review

Purpose

The growing incidence of renal cell carcinoma (RCC) raises many questions about the management of these patients. The late clinical presentation, the presence of locally advanced or metastatic disease at diagnosis, the difficulty of radical surgical excision, and radioresistance make it one of the more challenging tumors to treat. The primary objective of this article is to propose an updated and critical review of the role of radiotherapy (RT) in the treatment of RCC.

Methods

This literature review is based on data from meta-analyses and randomized, prospective, and retrospective studies. We collected reports from 1970 to the present about preoperative RT, postoperative RT, stereotactic body RT, radiosurgery, and intraoperative RT in locally advanced renal cancer and in metastatic diseases.

Results

We emphasize the progress made in RT technology that allowed the creation of a more personalized and focused treatment with a minimum rate of complications.

Conclusions

In the coming years, new studies will be published to confirm and increase the indications for use of RT.

Intraoperative radiotherapy in gynaecological and genito-urinary malignancies: focus on endometrial, cervical, renal, bladder and prostate cancers

Intraoperative radiotherapy (IORT) refers to the delivery of a single radiation dose to a limited volume of tissue during a surgical procedure. A literature review was performed to analyze the role of IORT in gynaecological and genito-urinary cancer including endometrial, cervical, renal, bladder and prostate cancers.

Literature search was performed by Pubmed and Scopus, using the words “intraoperative radiotherapy/IORT”, “gynaecological cancer”, “uterine/endometrial cancer”, “cervical/cervix cancer”, “renal/kidney cancer”, “bladder cancer” and “prostate cancer”. Forty-seven articles were selected from the search databases, analyzed and briefly described.

Literature data show that IORT has been used to optimize local control rate in genito-urinary tumours mainly in retrospective studies. The results suggest that IORT could be advantageous in the setting of locally advanced and recurrent disease although further prospective trials are needed to confirm this findings.

Does postoperative radiation therapy impact survival in non-metastatic sarcomatoid renal cell carcinoma? A SEER-based study

INTRODUCTION

The effect of adjuvant radiation therapy on survival in sarcomatoid renal cell carcinoma (sRCC) with no evidence of distant metastasis remains unclear.

METHODS

Subjects diagnosed with non-metastatic sRCC were identified using the Surveillance Epidemiology and End Results (SEER) (2004-2012) database and divided into groups based on their surgical treatment (ST): no surgery or radiation therapy (NSR); partial nephrectomy (PNE); radical nephrectomy with ureterectomy and bladder cuff resection (RNE + UE + BLAD); and radical nephrectomy (RNE). Certain radical nephrectomy cases also received adjuvant external-beam radiation therapy (RNE + RAD). The Kaplan-Meier method was used to estimate overall survival (OS). A multivariable competing risks regression analysis was used to calculate disease-specific survival (DSS) probability and to determine factors associated with cause-specific mortality (CSM).

RESULTS

A total of 408 patients were included in this study. The 5-year OS and predicted DSS were significantly higher in the patients who underwent STs (i.e., PNE, RNE + UE + BLAD, RNE, and RNE + RAD) (20.1-54.0 and 20.1-59.9 %, respectively) than in the NSR group (9.0 and 11.6 %, respectively) (P < 0.001). ST was independently associated with a decreased CSM (P < 0.0001). No significant differences in OS or the 1-, 3-, or 5-year DSS probabilities between the RNE and RNE + RAD groups were observed. RNE + RAD was not significantly associated with a decrease in 1-year CSM [subhazard ratio (SHR) 0.95; 95 % CI 0.23-3.96; P = 0.947].

CONCLUSIONS

Adjuvant external-beam radiation therapy did not increase OS in non-metastatic sRCC patients.

Synergistic immunotherapeutic effects of Lycium barbarum polysaccharide and interferon-α2b on the murine Renca renal cell carcinoma cell line in vitro and in vivo

Novel therapeutic strategies to improve clinical efficacy in patients with renal cell carcinoma (RCC) are required. The possibility of combination therapy with Lycium barbarum polysaccharides (LBP) and recombinant interferon (IFN)-α2b remains to be elucidated in RCC. The present study investigated the putative synergistic immunotherapeutic roles of LBP and IFN-α2b against RCC in vitro and in vivo. The mouse RCC cell line, Renca, was used for in vitro experiments. Treatment of the cells with a combination of LBP and IFN-α2b markedly inhibited cell proliferation, retarded cell cycle growth and promoted apoptosis in the Renca cells. Western blot analysis revealed that LBP and IFN-α2b synergistically downregulated the expression levels of cyclin D1, c-Myc and Bcl-2, and upregulated the expression of the antiapoptotic protein, Bax. Myeloid-derived suppressor cells (MDSCs) were markedly upregulated during tumour progression and promoted tumour growth by inhibiting the T-cell-mediated immune response. In vivo, a marked reduction in the MDSC ratio and tumour volume was observed in a group receiving combined treatment with LBP and IFN-α2b in a xenograft tumour model. In conclusion, the present study suggested that the combination of LBP and IFN-α2b is likely to be more effective in treating murine RCC compared with the less pronounced immunotherapeutic effects of administering LBP or IFN-α2b alone.

Bibliometrics of intraoperative radiotherapy: analysis of technology, practice and publication tendencies

PURPOSE

To analyze the performance and quality of intraoperative radiation therapy (IORT) publications identified in medical databases during a recent period in terms of bibliographic metrics.

MATERIALS AND METHODS

A bibliometric search was conducted for IORT papers published in the PubMed database between 1997 and 2013. Publication rate was used as a quantity indicator; the 2012 Science Citation Index Impact Factor as a quality indicator. Furthermore, the publications were stratified in terms of study type, scientific topic reported, year of publication, tumor type and journal specialty. We performed a one-way analysis of variance (ANOVA) to determine differences between the means of the analyzed groups.

RESULTS

Among the total of 207 journals, articles were reported significantly more frequently in surgery (n = 399, 41 %) and radiotherapy journals (n = 273, 28 %; p < 0.01). The highest impact factor was achieved by clinical oncology journals (p < 0.01). The majority of identified articles were retrospective cohort reports (n = 622, 64 %), followed by review articles (n = 204, 21 %; p < 0.001). Regarding primary topic, reports on cancer outcome following specific tumor therapy were most frequently published (n = 661, 68 %; p < 0.001) and gained the highest mean impact factor (p < 0.01). Gastrointestinal tumor reports were represented most frequently (n = 456, 47 %; p < 0.001) and the mean superior impact factor was earned by breast and gynecologic publications (p < 0.01).

CONCLUSION

We identified a consistent and sustained scientific productivity of international IORT expert groups. Most publications appeared in journals with surgical and radiooncological content. The highest impact factor was achieved by medical oncology journals.

Intraoperative electron radiation therapy (IOERT) in patients with locally recurrent renal cell carcinoma

BACKGROUND

To analyze our experience with intraoperative electron radiation therapy (IOERT) followed by moderate doses of external beam radiation therapy (EBRT) in patients with locally recurrent renal cell carcinoma.

METHODS

From 1992 to 2010, 17 patients with histologically proven, locally recurrent renal cell carcinoma (median tumor size 7 cm) were treated by surgery and IOERT with a median dose of 15 Gy. All patients met the premise of curative intent including 7 patients with oligometastases at the time of recurrent surgery, which were resected and/or irradiated. The median time interval from primary surgery to local recurrence was 26 months. Eleven patients received additional 3D-conformal EBRT with a median dose of 40 Gy.

RESULTS

Surgery resulted in free but close margins in 6 patients (R0), while 9 patients suffered from microscopic (R1) and 2 patients from macroscopic (R2) residual disease. After a median follow-up of 18 months, two local recurrences were observed, resulting in an actuarial 2-year local control rate of 91%. Eight patients developed distant failures, predominantly to liver and bone, resulting in an actuarial 2-year progression free survival of 32%. An improved PFS rate was found in patients with a larger time interval between initial surgery and recurrence (> 26 months). The actuarial 2-year overall survival rate was 73%. Lower histological grading (G1/2) was the only factor associated with improved overall survival. Perioperative complications were found in 4 patients. No IOERT specific late toxicities were observed.

CONCLUSIONS

Combination of surgery, IOERT and EBRT resulted in high local control rates with low toxicity in patients with locally recurrent renal cell cancer despite an unfavorable surgical outcome in the majority of patients. However, progression-free and overall survival were still limited due to a high distant failure rate, indicating the need for intensified systemic treatment especially in patients with high tumor grading and short interval to recurrence.