Divgi Chaitanya R, Pandit-Taskar Neeta, Jungbluth Achim A, Reuter Victor E, Gönen Mithat, Ruan Shutian, Pierre Christine, Nagel Andrew, Pryma Daniel A, Humm John, Larson Steven M, Old Lloyd J, Russo Paul
Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
Lancet Oncol. 2007 Apr;8(4):304-10. doi: 10.1016/S1470-2045(07)70044-X.
Preoperative identification of tumour type could have important implications for the choice of treatment for renal cancers. Antibody cG250 reacts against carbonic anhydrase-IX, which is over-expressed in clear-cell renal carcinomas. We aimed to assess whether iodine-124-labelled antibody chimeric G250 ((124)I-cG250) PET predicts clear-cell renal carcinoma, the most common and aggressive renal tumour.
26 patients with renal masses who were scheduled to undergo surgical resection by laparotomy received a single intravenous infusion of 185 MBq/10 mg of (124)I-cG250 over 20 min in this open-label pilot study. Surgery was scheduled 1 week after (124)I-cG250 infusion. PET and CT scanning of the abdomen, including the kidneys, within 3 h before surgery was planned for all patients. The obtained images were graded as positive (defined as a tumour-to-healthy-kidney ratio >3 to 1) or negative for antibody uptake, and the surgeon was informed of the scan results before surgery. After surgery, resected tumours were histopathologically classified as clear-cell renal carcinoma or otherwise. The trial is registered on the clinical trials site of the National Cancer Institute website http://clinicaltrials.gov/ct/show/NCT00199888.
One patient received inactive antibody and was excluded from analysis. 15 of 16 clear-cell carcinomas were identified accurately by antibody PET, and all nine non-clear-cell renal masses were negative for the tracer. The sensitivity of (124)I-cG250 PET for clear-cell kidney carcinoma in this trial was 94% (95% CI 70-100%); the negative predictive value was 90% (55-100%), and specificity and positive predictive accuracy were both 100% (66-100% and 78-100%, respectively).
PET with (124)I-cG250 can identify accurately clear-cell renal carcinoma; a negative scan is highly predictive of a less aggressive phenotype. Stratification of patients with renal masses by (124)I-cG250 PET can identify aggressive tumours and help decide treatment.
术前确定肿瘤类型可能对肾癌的治疗选择具有重要意义。抗体cG250可与碳酸酐酶IX发生反应，碳酸酐酶IX在透明细胞肾癌中过度表达。我们旨在评估碘-124标记的抗体嵌合体G250（（124）I-cG250）PET是否能预测透明细胞肾癌，这是最常见且侵袭性最强的肾肿瘤。
在这项开放标签试验研究中，26例计划接受剖腹手术切除肾肿块的患者在20分钟内静脉单次输注185 MBq/10 mg的（124）I-cG250。在输注（124）I-cG250后1周安排手术。计划对所有患者在手术前3小时内进行包括肾脏在内的腹部PET和CT扫描。将获得的图像根据抗体摄取情况分为阳性（定义为肿瘤与健康肾脏的比值>3比1）或阴性，并在手术前告知外科医生扫描结果。术后，将切除的肿瘤进行组织病理学分类为透明细胞肾癌或其他类型。该试验已在国家癌症研究所网站的临床试验网站http://clinicaltrials.gov/ct/show/NCT00199888上注册。
1例患者接受了无活性抗体，被排除在分析之外。16例透明细胞癌中有15例通过抗体PET准确识别，所有9例非透明细胞肾肿块对示踪剂均呈阴性。在该试验中，（124）I-cG250 PET对透明细胞肾癌的敏感性为94%（95%CI 70-100%）；阴性预测值为90%（55-100%），特异性和阳性预测准确性均为100%（分别为66-100%和78-100%）。
（124）I-cG250 PET能够准确识别透明细胞肾癌；扫描结果为阴性高度提示肿瘤侵袭性较低。通过（124）I-cG250 PET对肾肿块患者进行分层可识别侵袭性肿瘤并有助于决定治疗方案。
