Chemo and radionuclide therapy together with the addition of drugs that make patients more radiosensitive have been shown to diminish and even suppress neuroendeocrine tumors (NETs) from progressing in 70 percent of cases. As a result, peptide receptor chemo-radionuclide therapy (PRCRT) may offer patients improved survival rates, according to a study presented at the recent Society of Nuclear Medicine and Molecular Imaging 2014 Annual Meeting held June 7-11 in St. Louis.

The investigational PRCRT treatment is called Lu-177 DOTA-octreotate. This therapy was able to stabilize patients’ cancer after about a year from the completion of treatment, and is currently being evaluated in U.S. clinical trials as well as European and Australian studies.

“Lu-177 DOTA-octreotate (LuTate) peptide receptor radionuclide therapy is an emerging treatment for patients with inoperable NET with high somatostatin receptor expression,” said Grace Kong, MBBS, a principal investigator for the research conducted at the Centre for Cancer Imaging, Peter MacCallum Cancer Centre in Melbourne, Australia. “In contrast to other published series, our selection criteria were strictly restricted to patients with progressive disease or uncontrolled hormone-related symptoms on best supportive care.”

This study is unique because it involved not just LuTate, but an infusion of 5FU chemotherapy as a radiosensitizer for 63 out of 68 patients who underwent PRCRT. Participants in the study had already undergone a minimum of three courses of treatment with LuTate and were deemed inoperable presenting aggressive NETs expressing somatostatin hormone receptors.

“With these criteria we observed a high proportion of known Grade 2 disease, which has an adverse prognosis,” explained Kong. “The strength of our data is a long median follow-up of 60 months to assess for both objective response and survival.”

Results of the research showed 72 percent survival at two years and more than 50 percent of subjects survived longer than five years following treatment.