Study Applies Theranostics to Neuroendocrine Tumors (NET)

Graphic representation of DNA strands

Three patients have been enrolled in a study of the radioisotope Lutetium-177 (DOTA0, TYR3) Octreotate (Lu177- DOTATATE) at CHI Health, one of 30 study locations in the U.S.

The theranostics application of this drug is being studied for patients with specific types of neuroendocrine tumors, including carcinoid.

“It treats a patient’s tumor based on the individual characteristics of that tumor, not as part of a broad protocol,” said Sam Mehr, MD, CHI Health nuclear physician."

We do the diagnostic study with Ga-68 DOTATE PET; then we change the radioactive isotope from gallium to lutetium to perform a targeted therapy. The tumor-specific receptor can be imaged and then treated by changing the radioactive component of the bioactive molecule.

“When the therapeutic radioactive component strikes the tumor’s DNA, it breaks apart the strands of the DNA and that’s how it destroys the tumor.”

Lutetium-177 has been used in Europe for 15 years with good results. The radioisotope, which is individually formulated, comes from Italy.

“Those patients who got this drug, their progression-free survival advantage was greater than 75 percent compared to those who didn’t receive this drug,” Mehr said.

The approach also preserves surrounding tissues.

“We almost call these Trojan horses because the radiation is only released once it reaches the cancerous cells. For this disease, it’s a potential major improvement,” said Peter Silberstein, MD, CHI Health hematologist and oncologist.

The results were something even a patient could observe.

“At the end of the treatment they showed me the scan afterwards which showed an abundant amount of tumors killed off,” John Hrupek said. “We were doing backflips.”

The treatment resulted in minimal side effects, and Hrupek, who was diagnosed with a pancreatic NET last April, complained only of multiple trips to the bathroom after his first two of the four treatments.

“This is the initial drug in our theranostics program,” Mehr said. “We’re establishing a program in theranostics that will also be for prostate cancer and for breast cancer.”

Update: On January 26, 2018, Lutetium-177 received FDA approval.

Samuel H. Mehr, MD

Nuclear Medicine

Peter Silberstein, MD