Is there a role for stereotactic radiotherapy in the treatment of renal cell carcinoma?

Abstract

Renal cell carcinoma (RCC) has traditionally been regarded as radioresistant tumor based on preclinical data and negative clinical trials using conventional fractionated radiotherapy. However, there is emerging evidence that radiotherapy delivered in few fractions with high single-fraction and total doses may overcome RCC s radioresistance. Stereotactic radiotherapy (SRT) has been successfully used in the treatment of intra-and extracranial RCC metastases showing high local control rates accompanied by low toxicity. Although surgery is standard of care for non-metastasized RCC, a significant number of patients is medically inoperable or refuse surgery. Alternative local approaches such as radiofrequency ablation or cryoablation are invasive and often restricted to small RCC, so that there is a need for alternative local therapies such as stereotactic body radiotherapy (SBRT). Recently, both retrospective and prospective trials demonstrated that SBRT is an attractive treatment alternative for localized RCC. Here, we present a comprehensive review of the published data regarding SBRT for primary RCC. The radiobiological rationale to use higher radiation doses in few fractions is discussed, and technical aspects enabling the safe delivery of SBRT despite intra-and inter-fraction motion and the proximity to organs at risk are outlined.

The Role of Daily Adaptive Stereotactic MR-Guided Radiotherapy for Renal Cell Cancer

“…To the best of our knowledge, this is the first series of patients treated for primary RCC using MRgRT with routine daily plan re-optimization. We applied a commonly used fractionation scheme of 40 Gy in five fractions [ 18 , 23 , 24 ] in an overall treatment time of two weeks. Only a single patient reported nausea as acute toxicity, and no grade ≥ 2 late toxicity was observed.…”

“…Technical challenges in renal SABR include the management of intra-fractional motion, and potential solutions using an internal target volume-approach, fiducial-assisted robotic SABR or abdominal compression [ 18 ] have been described. Magnetic-resonance (MR)-guided radiotherapy (MRgRT) has been considered a promising option because of its improved visualization of kidney tumors in relation to critical adjacent organs such as a small bowel, duodenum, and stomach and the opportunity of real-time tumor tracking and automated gated delivery [ 18 , 19 ]. MRgRT also facilitates daily plan re-optimization as a means to reduce organs at risk (OAR) doses when abdominal organs are near the primary tumor.…”

Novel case of nephrocolic fistula secondary to stereotactic ablative body radiotherapy for clear cell renal cell carcinoma

“…7 Well-described side effects from SABR therapy for RCC include dermatitis, nausea, diarrhoea and impaired renal function. 8 This case illustrates the possibility of nephrocolic fistula formation as a complication of SABR treatment for clear cell RCC. This case also highlights the importance of considering nephrocolic fistula as a differential cause of haematochezia in a patient presenting in the context of SABR treatment for RCC.…”

“…SABR is emerging as another second‐line option for non‐surgical treatment of RCC in cases where partial or radical nephrectomy is not possible . Well‐described side effects from SABR therapy for RCC include dermatitis, nausea, diarrhoea and impaired renal function . This case illustrates the possibility of nephrocolic fistula formation as a complication of SABR treatment for clear cell RCC.…”

Online MR-guided radiotherapy – A new era in radiotherapy

“…Oligometastatic disease is now widely considered an indication for local treatment - Dennis Winkel will shed a light on how to optimally tackle individual lymph nodes [18]. And finally, Matthias Guckenberger [19] will introduce online MRgRT as alternative to surgery in renal cell carcinoma.…”