Imagine a world where cancer treatment, which is as precise as a laser, becomes even more targeted, minimizing harm to nearby tissues. It may sound futuristic, but a new type of cancer treatment called theranostics has made this a reality. With theranostics, doctors can target cancer with radiation at the cellular level, damaging tumors without harming nearby tissue by using agents that selectively bind radioisotopes to tumor cells.
Doctors at Sylvester Comprehensive Cancer Center, part of the Miller School, use theranostic treatments for hundreds of patients with prostate cancer and neuroendocrine tumors each year. Expanded facilities and investments will enable many more patients to access these innovative treatments as part of clinical trials soon.
Sylvester is one of the few sites in the U.S. with the specialized facilities and expertise to access first-in-human investigational radio-pharmaceuticals, including theranostic drugs. Through early clinical trials, Sylvester researchers are exploring the role theranostic drugs can play in several common cancers that urgently need better treatments.
“Theranostic treatments are more specific … to certain parts of a patient’s cancer, so we can target the tumor without damaging surrounding tissue.”
Targeting Tumors with Radioactive Probes
Theranostics is a type of radiation treatment powered by radioisotopes — unstable versions of elements that emit energy as they break down. At the heart of this approach is a powerful idea: combining cancer-targeting imaging probes with therapeutic doses of radiation to kill cancer cells.
Long before modern cancer medicine, radiation was the first “targeted” treatment. Although it has evolved over the years, the core concept remains: deliver the radiation as close to the cancer as possible to minimize harm to healthy cells. Theranostics represents the next step, getting the radioactive molecules to attach to cancer cells.
“Theranostic treatments are more specific and very targeted to certain parts of a patient’s cancer, so we can target the tumor without damaging surrounding tissue,” said Russ Kuker, M.D. ’02, Residency ’08, B.S. ’98, associate professor of radiology in the Division of Nuclear Medicine at Sylvester. “That means these treatments tend to have fewer side effects.”
Diagnostics Plus Therapy
A theranostic treatment begins with a positron emission tomography (PET) scan. This scan generates 3D images using radioisotopes that bind to cancer cells using targeting molecules. These molecules typically attach to proteins located on the surface of the cancer cells, known as receptors.
If the cancer has enough relevant receptors, it “lights up on the PET scan,” indicating that the patient may be a good candidate for theranostic treatment, Dr. Kuker said. “Then we use the same targeting molecule for the treatment itself. That’s what theranostics is.”
Radioactive elements vary in strength depending on the amount and type of energy they release. Radioactive elements that give off positively charged particles are used for imaging to assess the targeting molecule’s ability to find and attach to cancer cells. Radioactive elements that emit higher levels of cell-damaging energy are used for treatment, allowing potent radioactive therapies to come directly into contact with the cancer cells.
“You’re visualizing that the target is there,” said Matt Abramowitz, M.D., associate professor of clinical radiation oncology at the Miller School and co-leader of the Bladder, Kidney and Prostate Site Disease Group and vice chair of the Human Use Radiation Safety Committee at Sylvester. “You can see where it is in the patient. You’ve got it in your crosshairs.”
The treatment lutetium Lu 177 vipivotide tetraxetan is the first and only FDA-approved theranostics drug for prostate cancer. It targets a molecule called PSMA on prostate cancer cells, delivering radiation directly to the tumor. In clinical trials, lutetium Lu 177 vipivotide tetraxetan significantly improved survival rates for men with advanced prostate cancer. Sylvester has been providing this treatment to patients in South Florida since its approval in 2023.
Another approved theranostic drug, lutetium Lu 177 dotatate, treats neuroendocrine tumors, which can develop in many organ systems. This drug specifically targets tumor cells with somatostatin receptors, decreasing the risk of disease progression or death.
“You’re visualizing that the target is there. You can see where it is in the patient. You’ve got it in your crosshairs.”
Next-generation Clinical Trials
The next generation of studies will build on these successes, aiming to make the treatments better, safer and longer-lasting.
Sylvester has formed a dedicated theranostics research group to advance the theranostics program, including an expanded Radiation Safety Office (RSO) and clinical trial experts. Additionally, a new radioactive “hot lab” is equipped with the latest clinical trial tools. As an NCI-designated cancer center, Sylvester has the infrastructure for both theranostic research and clinical trials.
The RSO team is critical in keeping everybody safe — patients, their families, caregivers and the clinical staff. Walter Lamar, Ph.D., associate vice president for facilities operations and maintenance for UHealth – University of Miami Health System, and Maxwell Amurao, Ph.D., executive director for the University of Miami’s Radiation Control Program, have helped take the theranostics program to the next level. The RSO helps educate patients and address their anxieties about the safety of radioactive treatments.
Investments in high-end theranostic technologies and human expertise have enabled Sylvester to advance from conducting phase 2, phase 3 and industry trials to investigator-initiated first-in human research. Companies now contact the program to conduct sophisticated, intricate, early-stage trials.
Several new phase 1 and phase 2 clinical trials of theranostic treatments are underway, including trials targeting colorectal, breast, melanoma, pancreatic and other types of cancer. The theranostics team is collaborating with Sylvester experts in leukemia and breast cancer to expand clinical trials for these kinds of cancer. The team hopes to co-develop these treatments with pharmaceutical companies.
Patients with advanced disease that has already spread may have limited treatment options. The theranostics team aims to change that.
“Our center now has a very robust phase 1 program for patients who have exhausted all other possibilities,” Dr. Abramowitz said. “This offers them new options for hope.”
