Sun Maryellen R M, Brook Alexander, Powell Michael F, Kaliannan Krithica, Wagner Andrew A, Kaplan Irving D, Pedrosa Ivan
1 Department of Radiology, Harvard Medical School, Beth Israel Deaconess Medical Center, 330 Brookline Ave, CCW 3rd Fl, Boston, MA 02215.
2 Present address: Specialized Medical Imaging, Good Samaritan Medical Center, Brockton, MA.
AJR Am J Roentgenol. 2016 Mar;206(3):544-53. doi: 10.2214/AJR.14.14099.
The objective of our study was to assess the growth rate and enhancement of renal masses before and after treatment with stereotactic body radiotherapy (SBRT).
This retrospective study included all patients with renal masses who underwent SBRT during a 5-year period. Orthogonal measurements of renal masses were obtained on pre- and posttreatment CT or MRI. Pre- and posttreatment growth rates were compared for renal mass diameter and volume using the t test. Pre- and posttreatment tumor enhancement values were compared for tumors that underwent multiphasic contrast-enhanced MRI.
Forty patients underwent SBRT for the treatment of 41 renal tumors: clear cell renal cell carcinomas (RCCs) (n = 16), papillary RCCs (n = 6), oncocytic neoplasms (n = 8), unclassified RCCs (n = 2), urothelial carcinoma (n = 1), and no pathologic diagnosis (n = 8). The mean maximum tumor diameter before treatment was 3.9 cm (range, 1.6-8.3 cm). Three hundred thirty-eight pre- and posttreatment imaging studies were analyzed: 214 MRI studies and 124 CT studies. The mean pre- and posttreatment lengths of observation were 416 days (range, 2-1800 days) and 561 days (83-1366 days), respectively. The mean pretreatment tumor growth rate of 0.68 cm/y decreased to -0.37 cm/y post treatment (p < 0.0001), and the mean tumor volume growth rate of 21.2 cm(3)/y before treatment decreased to -5.35 cm(3)/y after treatment (p = 0.002). Local control-defined as less than 5 mm of growth-was achieved in 38 of 41 (92.7%) tumors. The Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 showed progression in one tumor (2.4%), stability in 31 tumors (75.6%), partial response in eight tumors (19.5%), and complete response in one tumor (2.4%). No statistically significant change in tumor enhancement was shown (mean follow-up, 142 days; range, 7-581 days).
Renal tumors treated with SBRT show statistically significant reductions in growth rate and tumor size after treatment but do not show statistically significant differences in enhancement in the initial (mean, 142 days) posttreatment period.
本研究的目的是评估立体定向体部放疗（SBRT）治疗前后肾肿块的生长速率及强化情况。
这项回顾性研究纳入了在5年期间接受SBRT治疗的所有肾肿块患者。在治疗前和治疗后的CT或MRI上对肾肿块进行正交测量。使用t检验比较治疗前后肾肿块直径和体积的生长速率。对接受多期对比增强MRI检查的肿瘤，比较治疗前后的肿瘤强化值。
40例患者接受SBRT治疗41个肾肿瘤，其中透明细胞肾细胞癌（RCC）16例、乳头状RCC 6例、嗜酸细胞瘤8例、未分类RCC 2例、尿路上皮癌1例、无病理诊断8例。治疗前肿瘤平均最大直径为3.9 cm（范围1.6 - 8.3 cm）。分析了338次治疗前和治疗后的影像检查：214次MRI检查和124次CT检查。治疗前和治疗后的平均观察时长分别为416天（范围2 - 1800天）和561天（83 - 1366天）。治疗前肿瘤平均生长速率为0.68 cm/年，治疗后降至-0.37 cm/年（p < 0.0001）；治疗前肿瘤平均体积生长速率为21.2 cm³/年，治疗后降至-5.35 cm³/年（p = 0.002）。41个肿瘤中有38个（92.7%）实现了局部控制（定义为生长小于5 mm）。实体瘤疗效评价标准（RECIST）1.1显示，1个肿瘤（2.4%）进展，31个肿瘤（75.6%）稳定，8个肿瘤（19.5%）部分缓解，1个肿瘤（2.4%）完全缓解。未显示肿瘤强化有统计学显著变化（平均随访142天；范围7 - 581天）。
接受SBRT治疗的肾肿瘤在治疗后生长速率和肿瘤大小有统计学显著降低，但在治疗后的初始阶段（平均142天）强化方面未显示统计学显著差异。
