“This work represents the first prospective clinical trial to determine whether PET using a radiolabeled antibody is sensitive and specific enough to permit identification of clear cell renal carcinoma,” said the study’s lead author, Chaitanya Divgi, MD, Chief of Nuclear Medicine and Clinical Molecular Imaging at the University of Pennsylvania.

In the study, the researchers used the radiolabeled monoclonal antibody G250. It has since been shown to target and bind to clear cell renal carcinoma and to react against an enzyme that is present in 94 percent of these cancers. Studies have also demonstrated that renal carcinoma has the highest recorded tumour uptake for G250 of any solid tumour, making the antibody ideal for use with PET imaging for this disease.

According to the study, 15 out of 16 clear cell renal carcinomas were correctly identified using G250 PET, resulting in a sensitivity of 94 percent. All nine patients with non-clear cell renal masses were negative on the PET scan – which is highly predictive of a less aggressive cancer – resulting in a specificity of 100 percent.

“Antibody PET could end up changing the standard of care for patients with kidney cancer,” said the study’s senior author, Paul Russo, MD, urologic cancer surgeon. “The excellent sensitivity and specificity of this tool supports the utility of G250 PET imaging as an alternative to biopsy for distinguishing renal lesions.” All patients were monitored for toxicity and the antibody infusion was well tolerated with no side effects or other adverse events related to the agent.

MEDICA.de; Source: Memorial Sloan-Kettering Cancer Center