Stein Alexandra J, Mayes Janice M, Mouraviev Vladimir, Chen Valerie H, Nelson Rendon C, Polascik Thomas J
Division of Urologic Surgery, Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA.
J Endourol. 2008 Nov;22(11):2433-9. doi: 10.1089/end.2008.0261.
We evaluated the clinical implication of persistent contrast enhancement demonstrated several months after laparoscopic renal cryoablation of a small renal mass.
Between September 2000 and May 2007, 30 patients underwent laparoscopic cryosurgery for an organ-confined renal tumor measuring <or=3.5 cm in diameter. A pure laparoscopic approach was used with third generation cryotechnology-17-gauge cryoprobes and argon-helium gas. The patients were followed by serial CT or MRI every 3 months after cryotherapy or until radiographic resolution of contrast enhancement at the site of ablation.
Of 30 patients (comprising 32 cases), by 3 months after cryosurgery, 27 (84.4%) treated renal masses demonstrated no contrast enhancement at the ablation site. However, 5 (15.6%) ablation sites showed enhancement at 3 months; three of those persisted by 6 months, but only one displayed enhancement by 9 months. The patient with persistent enhancement by 9 months underwent partial nephrectomy that demonstrated no recurrent cancer. All other enhancing ablation sites showed no enhancement by 10 months after cryotherapy without recurrence. No tumor, including those that demonstrated persistent enhancement after cryotherapy, showed enlargement at the ablation site.
This study demonstrates that persistent contrast enhancement at the cryoablation site is uncommon but may be detected by cross-sectional imaging up to 9 months after the procedure. The cause of persistent enhancement remains uncertain but may not be necessarily because of malignancy. These data suggest a benign etiology not necessitating further therapy and should be taken into account during post-treatment radiologic surveillance.
我们评估了腹腔镜下对小肾肿块进行冷冻消融术后数月出现的持续性对比增强的临床意义。
2000年9月至2007年5月期间，30例患者接受了腹腔镜冷冻手术，治疗直径≤3.5 cm的局限于肾内的肿瘤。采用单纯腹腔镜入路，使用第三代冷冻技术——17号冷冻探针和氩氦气。冷冻治疗后，每3个月对患者进行系列CT或MRI检查，直至消融部位对比增强在影像学上消失。
30例患者（共32个病例）中，冷冻手术后3个月时，27例（84.4%）治疗的肾肿块消融部位无对比增强。然而，5个（15.6%）消融部位在3个月时出现增强；其中3个在6个月时仍有增强，但到9个月时只有1个显示增强。9个月时仍有持续性增强的患者接受了部分肾切除术，术后未发现复发性癌症。所有其他增强的消融部位在冷冻治疗后10个月时均无增强，且无复发。没有肿瘤（包括冷冻治疗后出现持续性增强的肿瘤）在消融部位增大。
本研究表明，冷冻消融部位的持续性对比增强并不常见，但在术后长达9个月的时间里可通过横断面成像检测到。持续性增强的原因尚不确定，但不一定是由于恶性肿瘤。这些数据提示一种良性病因，无需进一步治疗，在治疗后的影像学监测中应予以考虑。
