18F-FDG PET／CT 对兔 VX2肉瘤射频消融疗效的评价：以病理作对照

摘要

Objective To evaluate the short‐term effect of radiofrequency ablation (RFA) for VX2 tumors in hind limbs of rabbits by PET/CT .Methods Sixteen rabbits with hind limbs VX2 tumors (thirty‐two lesions) were randomly divided into two groups:RFA group and control group ( underwent no any therapy) .Each group had 8 rabbits (16 lesions) .The rabbits were performed RFA at about twenty days after VX2 implantation .All rabbits were imaged with 18 F‐FDG PET/CT at one to three days before RFA and one week and four weeks after RFA .The rabbits in each group were sacrificed af‐ter imaging examination for pathology and immunohistochemistry studies .Results ① Before RFA ,the standardized up‐take value (SUV) of tumor tissue was 5 .306 ± 1 .246 .After treatment ,the SUVs of necrosis tissue were 2 .169 ± 0 .681 and 1 .987 ± 0 .611 respectively at one week and four weeks after RFA .The SUVs of inflammatory reaction were 2 .681 ± 0.353 and 2 .331 ± 0 .461 respectively .The SUVs decreased significantly after RFA ( P <0 .05) .The SUVs of residual tumor tissue (5 .606 ± 1 .254 ,5 .338 ± 1 .300) were higher than inflammatory reaction at one week and four weeks after RFA ;② There were 12 active lesions (75% ) and 4 completely lost active lesions confirmed by pathology after RFA . PET/CT detected 15 active lesions (94% ) and 13 active lesions (81% ) respectively at one week and four weeks after RFA .The results had no significant difference between PET/CT and pathology ( P>0 .05) .Conclusion 18 F‐FDG PET/CT can response pathological changes of rabbit VX2 tumors after RFA accurately .It is an excellent imaging modality of e‐valuating early therapeutic efficacy of radiofrequency ablation .%目的：评价PET／CT在兔后肢VX2肉瘤射频消融（radiofrequency ablation ，RFA ）术后近期疗效中的价值。方法16只载瘤兔（共32个肿瘤）随机分为两组：RFA治疗组和对照组（不作任何治疗），每组8只，16个肿瘤。在动物肿瘤模型制作后20天左右行射频治疗，治疗前1～3天、治疗后1周和4周进行PET／CT检查并于四周检查后处死，行病理学检查和免疫组织化学检测。结果① RFA术前肿瘤最大标准摄取值（standardized uptake value ，SUVmax）为5．306±1．246，RFA术后1周、4周坏死区SUVmax 分别为2．169±0．681、1．987±0．611，外周炎性反应SUVmax 分别为2.681±0．353、2．331±0．461，均明显低于RFA治疗前（ P ＜0．05）；RFA术后1周、4周残余瘤组织SUVmax （5．606±1.254、5．338±1．300）均明显高于炎性反应（ P ＜0．05）；②16个病灶RFA治疗后，经病理证实残留灶12例（75％），完全失去活性病灶4例；术后1周和4周，PET／CT分别发现残留灶15例（94％）和13例（81％），PET／CT和病理结果之间差异均无统计学意义（ P ＞0．05）。结论 PET／CT 能够准确反应兔后肢 VX2肉瘤射频消融术后的病理学变化，是评价RFA治疗早期疗效的一种理想方法。