Positron-emission tomography/computed tomography (PET/CT) with iodine-124 (124I) –girentuximab “can accurately and noninvasively identify” clear cell renal cell carcinoma, according to a phase III multicenter study reported in the Journal of Clinical Oncology. In addition, “PET/CT with 124I-girentuximab may be of value in risk stratification of patients with renal masses, and it fulfills an unmet medical need to improve appropriate patient care while minimizing the risks of invasive diagnostics and potentially unnecessary surgery,” the investigators concluded.
PET/CT and contrast-enhanced CT of the abdomen were performed on patients 2 to 6 days after intravenous 124I-girentuximab administration and before resection of renal masses. Among 195 patients with complete data sets (histopathologic diagnosis and PET/CT and contrast-enhanced CT results) available, the average sensitivity was 86.2% for PET/CT and 75.5% for contrast-enhanced CT (P = .023). The average specificity was 85.9% for PET/CT and 46.8% for contrast-enhanced CT (P = .005). “124I-girentuximab was well tolerated. There was no evidence of allergic reaction or drug intolerance,” the investigators stated.
“This multicenter trial demonstrated that 124I-girentuximab PET/CT could provide information on the presence or absence of [clear cell renal cell carcinoma] with accuracy at least comparable to that of biopsy, while obviating the need for this procedure with its inherent risks,” the authors asserted. In addition, 124I-girentuximab PET/CT “may play an important role in surgical planning by improving tumor characterization in patients with unilateral multicentric or bilateral lesions,” the authors stated.
“These data suggest,” the researchers pointed out, “ that patients presenting with incidentally identified T1 renal masses may benefit from the incorporation of 124I-girentuximab PET/CT to optimally inform a clinical management decision and add confidence and clarity to rational therapeutic recommendations for the surgically fragile, elderly, or comorbidly ill patient.” ■
Divgi CR, et al: J Clin Oncol 31:187-194, 2013.