Peptide receptor radioligand therapy (PRRT) is a type of targeted cancer treatment that uses radioactive materials linked to peptides to target and treat tumors that have receptors for certain hormones or growth factors.
Peptides are small proteins that can bind to specific peptide receptors on cells. In PRRT, synthetic peptide analogs are joined to a radioactive material, creating a "radioligand." When this radioligand is injected into the body, it circulates until finding and binding to peptide receptors on tumor cells. The radiation from the ligand destroys the tumor cells, while limiting damage to other cells in the body.
Some key points about peptide receptor radioligand therapy:
- PRRT enables targeted treatment by seeking out tumors bearing certain peptide receptors. This approach is used for cancers that have spread and lack clearly defined borders that can be targeted by other means.
- It is mainly used to treat neuroendocrine tumors (NETs) which impact hormone production and overexpress peptide receptors. But research is exploring PRRT for other cancer types too.
- The treatment delivers targeted radiation therapy by directly binding radioactive ligands to receptors on tumors cells. This limits exposure for healthy cells.
- Patients receive an intravenous injection of the radioactive ligand about once every 2 months. Most treatments involve 4 injections over many months.
- Side effects like nausea and fatigue can result from radiation exposure but are usually temporary. Other risks relate to the individual patient's health profile and response.
Some examples of receptor targets used:
- Somatostatin receptors: Overexpressed in 90% of gastroenteropancreatic neuroendocrine tumors. Radioactive somatostatin analog ligands like ^177^Lu-Dotatate or ^90^Y-Dotatoc target them.
- Glucagon-like peptide-1 receptors: Found in insulinomas and some intestinal tumors. ^68^Ga-DOTA-exendin-4 is an investigatory PRRT agent for targeting them.
- Gastrin releasing peptide receptors: Overexpressed in certain lung, breast and prostate cancers. Targeting them with PRRT is being studied.
The procedure involves several key steps:
- Patient screening to ID appropriate receptor targets and evaluate risks
- Infusion of the radioactive ligand via IV
- Imaging over time to view ligand binding and determine treatment efficacy
- Additional cycles every 6 to 12 weeks for maintained effect
While relatively new, over 2 decades of clinical experience support
PRRT as an effective option for receptor-positive, metastasized neuroendocrine cancers. When other treatments fail, response rates over 70% make it a valuable tool for controlling tumor growth and managing symptoms.
Researchers also envision expanded future applications if radioligand therapy continues demonstrating safety and success against other tumor types in clinical trials. Studies are mixed but show some promise for treating small cell lung cancer and prostate cancer when specific peptide receptors are overexpressed.
As leading hormonal health experts,
HormoVital utilizes advanced approaches like PRRT for qualifying patients. Our physicians have specialized expertise using gonadorelin and glucagon-like peptide receptor imaging and therapy to control growth in certain metastatic endocrine tumors. Contact our clinic if you have any questions or wish to explore targeted radioligand treatment options.
