A new approach to cancer treatment, known as theranostics, is gaining traction, combining advanced imaging with targeted therapy to personalize care. This evolving field, detailed in a recent podcast from the Cleveland Clinic’s Cancer Advances series, offers a promising avenue for more effective and less toxic cancer treatments.
Theranostics, as the name suggests, is a fusion of therapeutic and diagnostic techniques. It allows clinicians to not only visualize tumors with unprecedented precision but also to deliver radiation directly to cancer cells, minimizing damage to surrounding healthy tissue. The process begins with imaging, often using Positron Emission Tomography-Computed Tomography (PET-CT) scans, to identify specific targets – receptors – on cancer cells. Following identification, a therapeutic agent, carrying a radioactive payload, is administered to bind to those same targets, delivering a localized dose of radiation.
“The first step is imaging a patient with our dedicated PET-CT tools. The second step is treating those patients with particle radiation,” explains the concept as discussed in the podcast.
Currently, theranostics is being successfully applied in the treatment of prostate cancer and neuroendocrine tumors. For prostate cancer, PSMA PET (Prostate-Specific Membrane Antigen PET) imaging is used to identify cancer cells expressing the PSMA protein. What we have is followed by treatment with lutetium-177 PSMA, a beta particle-emitting radionuclide, which selectively targets and destroys the cancer cells. Similarly, somatostatin-based theranostics are utilized for neuroendocrine tumors, leveraging the high expression of somatostatin receptors on these cancer cells.
However, the potential of theranostics extends far beyond these initial applications. Researchers at the Cleveland Clinic are actively involved in clinical trials exploring the use of both beta and alpha particle therapies in a wider range of cancers, including melanoma, Merkel cell carcinoma, meningioma, neuroendocrine cancer, small cell lung cancer, and colorectal cancer. These trials are investigating different types of radioactive isotopes, including actinium-225, astatine-211, and lead-212, to optimize treatment efficacy and minimize side effects.
The choice of radiation type – beta or alpha particles – is crucial. Beta particles have a longer range and are suitable for treating larger tumors, while alpha particles deliver a more potent, highly localized dose of radiation, making them ideal for smaller, well-defined tumors. The podcast highlights the ongoing research into utilizing these different particles to maximize therapeutic impact.
A key advantage of theranostics is its ability to personalize treatment. By identifying patients who express the target receptor, clinicians can ensure that the therapy is delivered only to those who are most likely to benefit. This targeted approach not only increases treatment effectiveness but also significantly reduces the side effects associated with traditional cancer therapies, such as chemotherapy and radiation.
“Since we give therapy to the patients who express the intent to treat target receptors, our therapies are validated, and the side-effect profile is really patient-friendly,” as stated in the podcast discussion.
Radiation safety is, of course, a paramount concern when using radioactive isotopes for therapy. Clinicians are carefully trained in the administration of these agents and take appropriate precautions to minimize radiation exposure to both patients and healthcare personnel. The podcast addresses the importance of addressing these concerns with patients to ensure informed consent and alleviate anxieties.
The versatility of theranostics lies in its adaptability. Researchers are exploring the possibility of radiolabeling a wide range of compounds – peptides, antibodies, and small molecules – to target different receptors on various cancer cells. This allows for the development of customized theranostic agents tailored to the specific characteristics of each patient’s cancer. As Dr. Zan explains, once a receptor is identified, the radiation can be “changed” on the ligand to create a therapeutic agent.
The Cleveland Clinic has recently expanded its theranostics program to its Florida location, signaling a commitment to making this innovative treatment modality more accessible to patients. This expansion will allow more individuals to benefit from the precision and personalized care that theranostics offers.
While theranostics represents a significant advancement in cancer treatment, We see still an evolving field. Ongoing research is focused on identifying new targets, developing more effective radioligands, and optimizing treatment protocols. However, the early results are promising, and theranostics is poised to play an increasingly important role in the fight against cancer.
For those interested in learning more, the full podcast episode is available online at https://www.buzzsprout.com/2241774/17886547. Additional episodes of Cancer Advances can be found at clevelandclinic.org/podcasts/cancer-advances or through popular podcast platforms.
