Authors: Young Suk Kwon, Eric Hsu, Maggie Stein, Alana Christie, Aurelie Garant, Andrew Zhuang Wang, Daniel X. Yang, Allen Yen, Mihailo Miljanic, Kevin Dale Courtney, Hans J. Hammers, Tian Zhang, Waddah Arafat, Qian Qin, Suzanne Cole, James Brugarolas, Robert D. Timmerman, Raquibul Hannan
Published: 2023-06-04
DOI: 10.1200/jco.2023.41.16_suppl.e24156
Source: Full article
e24156 Background: Radiation therapy (RT) is routinely used for the palliation of metastatic renal cell carcinoma (mRCC) symptoms despite a paucity of literature on RT’s efficacy. Since RCC is considered radioresistant to conventionally fractionated RT, we retrospectively evaluated factors influencing effective symptom palliation with RT for mRCC. Methods: A retrospective review of patients with mRCC between 2011 and 2022 at a high-volume academic radiation center was performed to identify patients with symptomatic extracranial metastatic sites managed with RT. Radiation therapy techniques included three-dimensional conformal RT, intensity-modulated RT, and stereotactic body RT. Symptomatic indications for RT were categorized as pain, neurologic (weakness and numbness), respiratory (hemoptysis and cough), gastrointestinal/genitourinary (GI/GU) bleeding, or multiple. Symptom relief was evaluated from chart reviews at subsequent on-treatment visits or follow-up encounters. Time to symptom alleviation (days) was measured from the RT start date. Descriptive analyses were performed. Results: Of 243 patients included in the study cohort, there were 617 irradiated sites. 560 out of 617 (91.0%) patients were treated for pain, and the other symptoms included neurologic (6.8%), respiratory (3.9%), and GI/GU bleeding (1.5%). The most common RT regimen was 20Gy in 5 fractions (122 lesions; 19.8%) followed by 30Gy in 10 fractions (35 lesions; 5.7%). Symptom relief was observed in 84.9% (95%CI 81.4, 88.1) of patients for pain, 90.8% (95%CI 78.2, 97.6) for neurologic, and 69.9% (95%CI 49.3, 88.0) for respiratory symptoms. The overall proportion of symptom relief was 103/131 (79%) for 20 Gy in 5 fractions versus 27/38 (71%) for 30 Gy in 10 fractions (chi-square P = 0.3). Conclusions: RT is effective for symptom palliation of mRCC. Further studies are required to fully delineate the impact of dose-fractionation and RT modality. [Table: see text]