Carey Robert I, Leveillee Raymond J
Department of Urology, University of Miami, Miami, Florida 33136, USA.
J Endourol. 2007 Aug;21(8):807-13. doi: 10.1089/end.2007.9943.
To evaluate our experience with radiofrequency ablation (RFA) of renal tumors in the range of 3 to 5 cm.
A series of 96 patients underwent 104 tumor laparoscopic or percutaneous CT-guided RFAs. We identified 37 tumors between 3 and 5 cm at the time of the ablation. Non-conducting temperature probes, independent of the radiofrequency (RF) electrode, were placed at the peripheral and deep margins of the tumor in order to achieve real-time temperature monitoring of the ablation zone. All ablations were continued until the peripheral and deep temperature probes reached 60 degrees C.
All 37 patients (100%) achieved complete necrosis at the initial session. There were two radiographic failures at 9 months and 30 months that required a second treatment (95% radiographic success rate). Tissue samples taken at the time of the re-treatment (one partial nephrectomy with numerous biopsies of the deep and peripheral margins and one repeat ablation with eight core biopsies) showed no evidence of viable tumor with hematoxylin and eosin or nicotinamide adenine dinucleotide viability stains. The average length of follow-up was 11.3 months (range 1-44 months). No patient with localized disease at the time of the RFA developed local extension or metastatic disease in follow-up.
The majority of renal tumors between 3 and 5 cm can be ablated with complete necrosis in a single session. Placement of independent temperature probes at the peripheral and deep margins of the tumor provides real-time monitoring that assists in the deployments of the RF electrode and determining the appropriate duration of the ablation cycles. Attention to real-time thermometry decreases the need for repeat sessions to achieve complete necrosis for larger tumors. Likewise, real-time thermometry decreases the incidence of overtreatment of normal parenchyma and prevents collateral damage to adjacent vital structures (ureter, pancreas, bowel, spleen, nerves) outside the desired zone of ablation.
评估我们对3至5厘米肾肿瘤进行射频消融（RFA）的经验。
96例患者接受了104次肿瘤的腹腔镜或经皮CT引导下射频消融术。在消融时，我们确定了37个直径在3至5厘米之间的肿瘤。将与射频（RF）电极无关的非导电温度探头置于肿瘤的周边和深部边缘，以实现对消融区域的实时温度监测。所有消融持续进行，直至周边和深部温度探头达到60摄氏度。
所有37例患者（100%）在首次治疗时均实现了完全坏死。9个月和30个月时出现两例影像学治疗失败，需要进行二次治疗（影像学成功率为95%）。再次治疗时采集的组织样本（1例部分肾切除术，对深部和周边边缘进行多次活检，1例重复消融并进行8次芯针活检），苏木精-伊红染色或烟酰胺腺嘌呤二核苷酸活力染色均未显示有存活肿瘤的迹象。平均随访时间为11.3个月（范围1至44个月）。在RFA时患有局限性疾病的患者在随访中均未出现局部扩展或转移性疾病。
大多数3至5厘米的肾肿瘤可在单次治疗中实现完全坏死消融。在肿瘤周边和深部边缘放置独立的温度探头可提供实时监测，有助于射频电极的放置并确定消融周期的适当持续时间。关注实时温度测量可减少对较大肿瘤进行重复治疗以实现完全坏死的需求。同样，实时温度测量可降低正常实质过度治疗的发生率，并防止对消融所需区域外的相邻重要结构（输尿管、胰腺、肠、脾、神经）造成附带损伤。
