Stereotactic Body Radiotherapy for Stage I Renal Cell Carcinoma: National Treatment Trends and Outcomes Compared to Partial Nephrectomy and Thermal Ablation

Immunotherapy and stereotactic body radiotherapy for older patients with non-metastatic renal cancer unfit for surgery or decline nephrectomy: practical proposal by the International Geriatric Radiotherapy Group

The standard of care for non-metastatic renal cancer is surgical resection followed by adjuvant therapy for those at high risk for recurrences. However, for older patients, surgery may not be an option due to the high risk of complications which may result in death. In the past renal cancer was considered to be radio-resistant, and required a higher dose of radiation leading to excessive complications secondary to damage of the normal organs surrounding the cancer. Advances in radiotherapy technique such as stereotactic body radiotherapy (SBRT) has led to the delivery of a tumoricidal dose of radiation with minimal damage to the normal tissue. Excellent local control and survival have been reported for selective patients with small tumors following SBRT. However, for patients with poor prognostic factors such as large tumor size and aggressive histology, there was a higher rate of loco-regional recurrences and distant metastases. Those tumors frequently carry program death ligand 1 (PD-L1) which makes them an ideal target for immunotherapy with check point inhibitors (CPI). Given the synergy between radiotherapy and immunotherapy, we propose an algorithm combining CPI and SBRT for older patients with non-metastatic renal cancer who are not candidates for surgical resection or decline nephrectomy.

Perioperative Nephrectomy Outcomes for Patients with Liver Disease: Implications for Liver Transplant Candidates

OBJECTIVE

To improve the management of cirrhotic patients diagnosed with new renal masses, we used a nationally representative cohort to assess the perioperative outcomes of nephrectomy in the setting of liver disease. The incidences of liver disease and renal masses are both rising in the US. Delaying liver transplantation to address other health concerns may have life changing consequences in these patients, thus these results help to guide treatment decisions at this critical junction in care.

METHODS

A retrospective study of the 2016-2019 Nationwide Readmissions Database was performed in adults undergoing nephrectomy for non-emergent indications. Outcomes were compared between 3 cohorts: no chronic liver disease (no CLD), chronic liver disease (CLD), and decompensated cirrhosis (DC). Mixed regression models were used to evaluate the association between CLD and DC with outcomes of interest including morbidity, mortality, readmission rates, non-home discharges, length of stay, and costs.

RESULTS

A total of 183,362 patients were evaluated. The mortality rate in the DC cohort (7%) was higher than with CLD (0.4%) and no CLD (0.3%), (P <.001). DC was associated with higher mortality (OR 8.29, 95% CI 4.07 - 16.88), postoperative bleeding requiring transfusion (OR 5.55, 95% CI 3.72 - 8.26), non-home discharge (OR 5.12, 95% CI 3.16 - 8.30) and readmission (OR 1.79, 95% CI 1.09 - 2.94) compared to no CLD. The DC cohort had the greatest length of stay and costs.

CONCLUSION

Patients undergoing nephrectomy with DC have increased morbidity, mortality, readmission rates, non-home discharges, LOS and costs. Alternative management strategies may be considered in these patients.

Stereotactic Body Radiotherapy for Kidney Cancer: Ready for Prime Time?

The standard treatment for renal cell carcinoma (RCC) is surgery. However, a number of patients will not be candidates for surgical treatment or will reject this therapeutic approach. Therefore, alternative approaches are required. Historically, radiotherapy has been considered an ineffective treatment for RCC due to the radioresistance of renal tumour cells to conventional fractionation and the increased rate of toxicity. Stereotactic body radiotherapy (SBRT) is a radiotherapy technique that provides a non-invasive ablative treatment with remarkable rates of local control in both primary tumours and metastases in several locations, with a low associated morbidity due to the highly conformal dose and the use of image-guided techniques. Current evidence shows that a higher dose per fraction, achieving a higher biological effective dose, can overcome the radioresistance of RCC cells. Therefore, SBRT, as well as the combination of SBRT and new emerging immune therapies, has a potential role in the local treatment of primary RCC and oligometastatic RCC patients.

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.

5-year outcomes after stereotactic ablative body radiotherapy for primary renal cell carcinoma: an individual patient data meta-analysis from IROCK (the International Radiosurgery Consortium of the Kidney)

BACKGROUND

Stereotactic ablative body radiotherapy (SABR) is a non-invasive treatment option for primary renal cell carcinoma, for which long-term data are awaited. The primary aim of this study was to report on long-term efficacy and safety of SABR for localised renal cell carcinoma.

METHODS

This study was an individual patient data meta-analysis, for which patients undergoing SABR for primary renal cell carcinoma across 12 institutions in five countries (Australia, Canada, Germany, Japan, and the USA) were eligible. Eligible patients had at least 2 years of follow-up, were aged 18 years or older, had any performance status, and had no previous local therapy. Patients with metastatic renal cell carcinoma or upper-tract urothelial carcinoma were excluded. SABR was delivered as a single or multiple fractions of greater than 5 Gy. The primary endpoint was investigator-assessed local failure per the Response Evaluation Criteria in Solid Tumours version 1.1, and was evaluated using cumulative incidence functions.

FINDINGS

190 patients received SABR between March 23, 2007, and Sept 20, 2018. Single-fraction SABR was delivered in 81 (43%) patients and multifraction SABR was delivered in 109 (57%) patients. Median follow-up was 5·0 years (IQR 3·4-6·8). 139 (73%) patients were men, and 51 (27%) were women. Median age was 73·6 years (IQR 66·2-82·0). Median tumour diameter was 4·0 cm (IQR 2·8-4·9). 96 (75%) of 128 patients with available operability details were deemed inoperable by the referring urologist. 56 (29%) of 190 patients had a solitary kidney. Median baseline estimated glomerular filtration rate (eGFR) was 60·0 mL/min per 1·73 m2 (IQR 42·0-76·0) and decreased by 14·2 mL/min per 1·73 m2 (IQR 5·4-22·5) by 5 years post-SABR. Seven (4%) patients required dialysis post-SABR. The cumulative incidence of local failure at 5 years was 5·5% (95% CI 2·8-9·5) overall, with single-fraction SABR yielding fewer local failures than multifraction (Gray's p=0·020). There were no grade 3 toxic effects or treatment-related deaths. One (1%) patient developed an acute grade 4 duodenal ulcer and late grade 4 gastritis.

INTERPRETATION

SABR is effective and safe in the long term for patients with primary renal cell carcinoma. Single-fraction SABR might yield less local failure than multifraction, but further evidence from randomised trials is needed to elucidate optimal treatment schedules. These mature data lend further support for renal SABR as a treatment option for patients unwilling or unfit to undergo surgery.

FUNDING

None.

Stereotactic Body Radiotherapy for Localized Kidney Cancer

PURPOSE OF REVIEW

Stereotactic body radiation therapy (SBRT) is increasingly utilized in the management of localized kidney cancers, particularly for patients who are not surgical candidates. Herein, we provide a narrative review of SBRT in the management of localized kidney cancers.

RECENT FINDINGS

Recent prospective studies and multi-institutional retrospective studies highlight the safety and efficacy of SBRT in the management of renal tumors, a disease previously thought to be radioresistant. Studies have shown that local control is greater than 90% with rare grade 3 or 4 toxicity and no grade 5 toxicity. SBRT can be utilized successfully in the treatment of large kidney tumors (> 5 cm). New techniques such as MRI-guided radiation therapy may further improve the therapeutic ratio. However, randomized clinical trials are necessary to confirm the optimal dosing schedule and compare outcomes with nephrectomy, which remains the standard of care in suitable patients. Advances in SBRT have made this modality a safe and effective treatment option in the management of localized kidney cancers.

Stereotactic body radiotherapy for kidney cancer: a 10-year experience from a single institute

The purpose of this retrospective study was to investigate survival outcomes and irradiated tumor control (local control [LC]) and locoregional control (LRC) after stereotactic body radiotherapy (SBRT) for T1 or recurrent T1 (rT1) kidney cancer. Twenty-nine nonconsecutive patients with 30 tumors were included. SBRT doses of 70 Gy, 60 Gy or 50 Gy in 10 fractions were prescribed with a linear accelerator using daily image guidance. The Kaplan-Meier method was used to estimate time-to-event outcomes, and the log-rank test was used to compare survival curves between groups divided by each possible factor. The median follow-up periods for all patients and survivors were 57 months and 69.6 months, respectively. The five-year LC rate, LRC rate, progression-free survival (PFS) rate, disease-specific survival (DSS) rate and overall survival (OS) rate were 94%, 88%, 50%, 96% and 68%, respectively. No significant factor was related to OS and PFS. Three of 24 non-hemodialysis (HD) patients had new-onset-HD because of the progression of underlying kidney disease. Grade 3 or higher toxicities from SBRT did not occur. In conclusion, SBRT for kidney cancer provided a high rate of LC, LRC and DSS with minimal toxicities, but patient selection and indication for SBRT should be done carefully considering the relatively low OS rate.

Thermal Ablation Versus Wedge Resection for Stage I Non-small Cell Lung Cancer Based on the Eighth Edition of the TNM Classification: A Population Study of the US SEER Database

Background

The incidence rates of early-stage non-small cell lung cancer (NSCLC) are now increasing, and therapies such as thermal ablation have shown potential therapeutic promise. This study aimed to determine the influence of different surgical methods on overall survival (OS) and cancer-specific survival (CSS) in patients with stage I NSCLC.

Methods

Patients diagnosed with stage I NSCLC who had received thermal ablation or wedge resection between 2004 and 2014 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed according to the surgical method. Kaplan–Meier curves and a Cox proportional hazard model were used to evaluate OS and CSS.

Results

In all, 4,372 patients with stage I NSCLC were included. Before PSM, the respective 3- and 5-year OS rates were 68.9 and 52.7% in the wedge resection group and 68.5 and 47.8% in the thermal ablation group (p < 0.0001); the corresponding CSS rates were 79.1 and 69.4% and 62.6 and 46.0% (p < 0.0001). After PSM, survival analysis showed that wedge resection had better OS (44.5% vs. 30.1%, p = 0.033) and CSS (63.5% vs. 46%, p = 0.038) than thermal ablation. After PSM, Cox regression showed that treatment was not associated with OS or CSS. For patients aged >75 years, thermal ablation showed similar OS and CSS as wedge resection (OS: 30.6% vs. 41.7%, p = 0.470; CSS: 46.4% vs. 64.1%, p = 0.100). After PSM, thermal ablation still had OS (30.6% vs. 41.0%, p = 0.470) and CSS (46.4% vs. 59.8%, p = 0.100) comparable to wedge resection.

Conclusion

For patients with stage I NSCLC who are unfit for lobectomy, thermal ablation could be a potential therapeutic option, especially for those >75 years old.