Long-term outcomes after maximal surgical resection and intraoperative electron radiotherapy for locoregionally recurrent or locoregionally advanced primary renal cell carcinoma

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.

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.

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.

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.

Stereotactic body radiotherapy (SBRT) for pulmonary metastases from renal cell carcinoma-a multicenter analysis of the German working group "Stereotactic Radiotherapy"

Background

Renal cell carcinoma (RCC) is traditionally considered to be radioresistant. Radiotherapy response rates are believed to improve with hypofractionated, high dose stereotactic body radiotherapy (SBRT). However, limited data exist regarding the role of SBRT in the treatment of pulmonary metastases.

Methods

The working group "Stereotactic Radiotherapy" of the German Society of Radiation Oncology analyzed its multi-institutional database of more than 700 patients who received SBRT for pulmonary metastases. Treatment was performed at 10 centers between 2001 and 2016. Patients with metastatic RCC were included in the study. Tumor characteristics, treatment details, and follow-up data including survival, local control (LC), distant metastases, and toxicity were evaluated.

Results

A total of 46 RCC patients treated with SBRT for 67 lung metastases were identified, who received a median total biologically effective dose (BED_iso) at planning target volume (PTV) isocenter of 117.0 Gy (range, 48.0-189.0 Gy). A median fractional dose of 20.8 Gy at isocenter (range, 6.0-37.9 Gy) was administered in a median number of 3 fractions (1-8 fractions). After a median follow-up time of 28.3 months for all patients, 1- and 3-year LC rates were 98.1% and 91.9%, with corresponding 1- and 3-year overall survival (OS) of 84.3% and 43.8%, respectively. Pulmonary metastases treated with BEDiso ≥130 Gy showed a trend for superior LC (P=0.054). OS was significantly improved in both uni- and multivariate analysis for patients with higher Karnofsky performance scale, lower maximum pulmonary metastasis diameter and lack of post-SBRT systemic therapy due to progression (P=0.014; P=0.049; P=0.006). Only mild acute and late toxicity was reported.

Conclusions

SBRT for pulmonary metastases from RCC was associated with low treatment-associated toxicity, promising survival, and excellent LC, especially in those patients receiving a BED_iso ≥130 Gy.

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.

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.

Local Recurrence After Curative Surgical Treatment of Renal Cell Cancer: A Study of 91 Patients

BACKGROUND

Local recurrence (LR) after curative therapy for renal cell cancer is a rare event, and surgery is still the primary treatment option.

PATIENTS AND METHODS

This was a single-institution, single-arm retrospective study from a prospectively conducted database. A total of 91 patients with a median age of 63.0 years (interquartile range, 57.5-68.3), who had undergone LR resection after initial curative treatment of RCC were enrolled. The time to LR (TTLR) was defined as the interval from primary curative surgery to LR. Cancer-specific survival, overall survival, and progression-free survival were evaluated after LR resection. Statistical analyses of the clinical and pathologic variables were performed using Cox regression analysis and the Kaplan-Meier method.

RESULTS

The median time to LR was 29.8 months (interquartile range, 10.8-64.3). On multivariate analysis, age > 65 years, T3/T4 stage, Fuhrman grade 3/4, major venous infiltration, and positive surgical margins were related to early LR after primary curative surgery. LR size of ≤ 7 cm and TTLR of > 24 months were associated with longer cancer-specific survival. Furthermore, patients with a TTLR of > 24 months had better overall survival and progression-free survival. Of the entire cohort, intraoperative radiation therapy and targeted therapy were used in 17 (18.7%) and 15 (16.5%) patients, respectively.

CONCLUSION

Advanced age, T3/T4 stage, Fuhrman grade 3 or 4, major venous infiltration, and positive surgical margins at primary tumor resection were related to a greater risk of early LR. An LR size of ≤ 7 cm and TTLR of > 24 months were associated with favorable oncologic outcomes after LR resection. Thus, patients who present with a longer TTLR and smaller LR size, along with favorable features at primary tumor resection, will benefit from surgical treatment.

Intraoperative radiotherapy in early stage breast cancer: potential indications and evidence to date

Following early results of recent studies of intraoperative radiotherapy (IORT) in the adjuvant treatment of patients with early breast cancer, the clinical utility of IORT is a subject of much recent debate within the breast oncology community. This review describes the intraoperative techniques available, the potential indications and the evidence to date pertaining to local control and toxicity. We also discuss any implications for current practice and future research.

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.

Present status and future directions of intraoperative radiotherapy

In this Review, we summarise recent published work on the use of intraoperative radiotherapy to treat common tumour sites in the primary or recurrent setting. Techniques, radiobiology, and the physics of intraoperative radiotherapy are also explored. Disease sites discussed in this Review include head and neck cancer, breast cancer, sarcoma, gastrointestinal cancer, genitourinary cancer, gynaecological cancer, thoracic cancer, and palliative applications.

Cardiac Metastasis in Renal Cell Carcinoma without Vena Cava or Atrial Involvement: an Unusual Presentation of Metastatic Disease

Cardiac metastasis in renal cell carcinoma is a very rare entity, with only a few previously reported cases. In this series, we report two cases of ventricular metastases from renal cell carcinoma without vena cava or right atrial involvement. The first case involves an initially isolated inoperable metastasis to the left ventricle, which was treated with systemic targeted therapy with favorable local response. Our second case illustrates a patient with an isolated cardiac metastasis in the interventricular septum with extension into the right ventricle, which has also remained stable in size on systemic targeted therapy. Although anti-angiogenic agents such as tyrosine kinase inhibitors have transformed the treatment of metastatic renal cell carcinoma in recent years, their efficacy and safety in treating patients with metastatic disease in highly vascular organs such as the heart are currently unknown, with no prior reports on this topic. We describe our novel management of these unique cases and discuss the current medical and surgical approaches to treating cardiac metastases from renal cell carcinoma.

Intraoperative EBRT and resection for renal cell carcinoma : twenty-year outcomes

PURPOSE

We report the outcomes of a multimodality treatment approach combining maximal surgical resection and intraoperative electron radiotherapy (IOERT) with or without external beam radiation therapy (EBRT) in patients with locoregionally (LR) recurrent renal cell carcinoma (RCC) after radical nephrectomy or LR advanced primary RCC.

PATIENTS AND METHODS

From 1983 to 2008, 25 patients with LR recurrent (n = 10) or LR advanced primary (n = 15) RCC were treated with this approach. Median patient age was 60 years (range, 16-79 years). Fifteen patients (60%) received perioperative EBRT (median dose, 44 Gy). Surgical resection was R0 (negative margins) in 6 patients (24%) and R1 (residual microscopic disease) in 19 patients (76%). The median dose of IOERT was 14 Gy (range, 9-15). Overall survival (OS) and relapse patterns were calculated using the Kaplan-Meier method.

RESULTS

Median follow-up for surviving patients was 22.2 years (range, 3.6-26 years). OS and DFS at 5 and 10 years were 38% and 18% and 19% and 14%, respectively. LR control (tumor bed or regional lymph nodes) and distant metastases-free survival rates at 5 years were 80% and 22%, respectively. The death rate within 30 days of surgery and IOERT was 4% (n = 1). Six patients (24%) experienced acute or late toxicities of grade 3 or higher according to the National Cancer Institute Common Toxicity Criteria (NCI-CTCAE) v4.

CONCLUSION

In patients with LR recurrent or LR advanced primary RCC, a multimodality approach consisting of maximal surgical resection and IOERT with or without adjuvant EBRT yielded encouraging local control results, justifying further evaluation.