Preoperative characterisation of clear-cell renal carcinoma using iodine-124-labelled antibody chimeric G250 (124I-cG250) and PET in patients with renal masses: a phase I trial

Lancet Oncol. 2007 Apr;8(4):304-10. doi: 10.1016/S1470-2045(07)70044-X.


Background: 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.

Methods: 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

Findings: 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).

Interpretation: 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.

Publication types

  • Clinical Trial, Phase I
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibodies, Monoclonal* / administration & dosage
  • Carcinoma, Renal Cell / diagnosis*
  • Carcinoma, Renal Cell / metabolism
  • Diagnosis, Differential
  • Female
  • Humans
  • Infusions, Intravenous
  • Iodine Radioisotopes
  • Kidney / diagnostic imaging
  • Kidney / metabolism
  • Kidney / pathology
  • Kidney Neoplasms / diagnosis*
  • Kidney Neoplasms / metabolism
  • Male
  • Middle Aged
  • Pilot Projects
  • Positron-Emission Tomography*
  • Preoperative Care
  • Sensitivity and Specificity


  • Antibodies, Monoclonal
  • G250 monoclonal antibody
  • Iodine Radioisotopes

Associated data