Stereotactic Body Radiation Therapy (SBRT) for Palliative Treatment of Gross Hematuria from Upper Tract Urothelial Carcinoma - Expert Commentary

Gross hematuria is a distressing symptom for patients with upper urinary tract urothelial cancers (UTUC). Invasive procedures are usually employed to control hematuria, including surgical resection, endoscopic laser ablation, and percutaneous nephroscopic resection. Stereotactic body radiation therapy (SBRT) is a non-invasive, targeted radiation therapy technique frequently applied in curative and palliative settings. It involves a short treatment course (3-5 fractions), maximum dose delivery to the target lesion, and optimal sparing of the surrounding organs. SBRT application in the management of UTUC is usually limited due to the risk of kidney and bowel injury.

A recent study published by Aronowitz et al. investigated the efficacy and safety of SBRT to palliate gross hematuria secondary from UC of the renal pelvis. Eight patients with uncontrolled hematuria from renal pelvis/calyces lesions measuring up to 4 cm. Treatment was delivered over 3-5 fractions in non-consecutive days with an average treatment time of 17.2 minutes per fraction. Radiation doses ranged from (600-900 cGy) per fraction to a maximum total dose of 4500 cGy according to the target's location.

All patients tolerated treatment well with control of hematuria within a week from the last fraction. During the follow-up period, two patients experienced recurrent hematuria. Regarding the adverse impact on renal function, four patients experienced an increase in creatinine following SBRT. The mean decline of estimated glomerular filtration rate (eGFR) in patients followed for more than a year was 22%.

Although urothelial cancers are more radiosensitive compared to renal cell carcinomas (RCC), there is limited data on using SBRT for the management of UTUC.  The balance between the maximum dose tolerated by a single kidney (2000 cGy in 10 fractions) and a tumoricidal dose to the renal UTUC is very challenging due to the lesions' central location. In addition, the extent of eGFR decline after SBRT is not clearly defined.

The authors conclude that SBRT is well-tolerated and effective in palliating gross hematuria secondary to UC of the renal pelvis. Despite the small sample size, this study highlights the feasibility and efficacy of SBRT doses in palliating distressing symptoms such as hematuria. This non-invasive approach offers potential advantages in elderly, frail UTUC patients who may not be fit for surgical intervention. The management of UC has markedly evolved over the last few years with the incorporation of immunotherapy. Studying the combination of the currently approved immunotherapeutic agents and ablative doses of radiation therapy delivered by SBRT is underway.

Written by: Bishoy M. Faltas, MD, Director of Bladder Cancer Research, Englander Institute for Precision Medicine, Weill Cornell Medicine, New York City, New York

References:

  1. Aronowitz J, Ding L, Yates J, Zong Y, Zheng L, Jiang Z, et al. Stereotactic Body Radiotherapy for Palliation of Hematuria Arising From Urothelial Carcinoma of the Kidney in Unfavorable Surgical Candidates. Am J Clin Oncol. 2021;00(00):1–6. PMID: 33710134

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