Prostate cancer is the second leading cause of cancer-related deaths among men in the United States, and its incidence is increasing. More than 300,000 men are diagnosed each year, with the number growing annually. Aging populations and improved screening have contributed to the rise. While most prostate cancers grow slowly and are caught early, a significant number progress, and one in 44 men will ultimately die from the disease.
An emerging approach in nuclear medicine, called theranostics, is showing promising results in the fight against prostate cancer, particularly in its advanced stages. The term “theranostics” merges “therapy” and “diagnostics,” reflecting its dual capability to detect and treat cancer simultaneously.
The concept has been around since the 1940s, initially used for thyroid cancer with radioactive iodine. However, recent technological advances have allowed for more precise and targeted approaches. Using specially designed radiopharmaceuticals, doctors can locate and destroy cancer cells while minimizing damage to healthy tissues.
For prostate cancer, this involves a PET scan combined with a radiotracer that binds to prostate-specific membrane antigens (PSMA) found on cancer cells. Once the cancerous areas are identified, a therapeutic radiotracer is administered. This radioactive substance travels the same path as the diagnostic agent and delivers targeted radiation to destroy the malignant cells.
Before treatment begins, doctors conduct extensive testing to ensure the patient is a good candidate. This may include PET scans, molecular tests, and dosimetry, which helps personalize the radiation dose. The treatment itself is straightforward: an IV infusion of the diagnostic radiotracer is followed by the therapeutic one. The process is repeated every six weeks for up to six cycles.
Patients are given strict safety guidelines after each treatment cycle to reduce the risk of radiation exposure to others. These include sleeping in a separate room, using separate utensils and linens, and drinking lots of water to flush out radioactive materials.
Theranostics is most effective in treating advanced, metastatic prostate cancer, where tumors have spread beyond the prostate and surgery is no longer viable. The treatment offers the advantage of targeting multiple cancer sites throughout the body, guided by the principle: “see what you treat and treat what you see.”
Success stories have shown that some patients with late-stage disease experience substantial improvements in both lifespan and quality of life. Patients who were expected to live only a few months have seen their lives extended by a year or more, with manageable side effects.
In 2022, the FDA approved Pluvicto, the first theranostic drug for advanced prostate cancer. It combines a diagnostic agent to locate cancer cells and a therapeutic agent to destroy them. Newer approaches use actinium-225, an alpha particle emitter that is significantly more powerful than the more commonly used beta particles. These alpha particles deliver stronger hits to cancer cells with minimal impact on surrounding tissues.
Despite the promise, theranostics is not without challenges. The treatment is expensive, with a full course costing around $240,000. While it is covered by many insurance plans and Medicare, Medicaid coverage varies. Access is also limited, with only a handful of specialized centers offering the treatment. Additionally, the supply of actinium-225 remains limited, which has slowed wider adoption.
Though not a cure, theranostics represents a major advancement in prostate cancer care, especially for patients with advanced disease. As research continues and accessibility improves, it holds the potential to significantly improve outcomes for many.
