The word cure seems to be disappearing from talk about cancer. These days, doctors are more likely to talk about cancer control, rather than cure. This is partly because cancers that used to be a death sentence are now seen as a chronic disease that patients can live with for years, thanks to recent target and-manage therapies that control ongoing problems as they arise.
However, when prostate cancer (PCa) is diagnosed and treated early, 95% of patients appear to be “cured”. This means there are no future signs that their disease is back. They go about their lives, and ultimately die from other causes.
Tragically, some men are diagnosed when their cancer has already begun to spread (metastasize) to other parts of the body. While there is still no cure for metastatic prostate cancer (mPCa), there is a new method for destroying PCa that has colonized bone and/or other organ tissues. It is a hope-filled, exciting new treatment approach called theranostics, a term that’s a blend of therapy and diagnostics.
The new treatment, called 177Lu-PSMA-617, is described in a Memorial Sloan Kettering newsletter as using “…a molecule that selectively seeks out and attaches to a specific protein on the cancer cell surface called PSMA (prostate-specific membrane antigen). The technology delivers radiation that damages DNA and destroys the cancer cell.”
This approach evolved from PSMA-PET scanning to detect prostate cancer recurrence, which is often metastatic. Since PCa cells have 100-1000 times more PSMA on their surface than normal cells, tiny radiotracer molecules stick to them like glue, and light up on PET scans. This reveals the location of even very small sites of PCa tumors. So, it was logical that if imaging could take advantage of PSMA to target cell locations, the next step would be harnessing this technology to deliver a lethal blow to the cells themselves.
The radiopharmaceutical manufacturer of 177Lu-PSMA-617, Novartis, states, “After administration into the bloodstream, 177Lu-PSMA-617 binds to prostate cancer cells that express PSMA, a transmembrane protein, with high tumor-to-normal tissue uptake.. Once bound, emissions from the radioisotope damage tumor cells, disrupting their ability to replicate and/or triggering cell death.” A clinical trial called VISION, a phase 3 study, enrolled 381 patients with PSMA-detectable mPCa that no longer responded to androgen deprivation therapy. The investigators found, “The PSMA-targeted radioligand 177Lu-PSMA-617 prolonged overall survival and delayed imaging-based progression when added to standard care in patients with PSMA-expressing metastatic castration-resistant prostate cancer.”[i]
177Lu-PSMA-617 is not yet a complete cure, but it offers longer life. With the abundance of research occurring, a definitive cure may be just around the corner. It’s worth it to extend a man’s lifetime in hopes that that corner is turned as soon as possible.
NOTE: This content is solely for purposes of information and does not substitute for diagnostic or medical advice. Talk to your doctor if you are experiencing pelvic pain, or have any other health concerns or questions of a personal medical nature.
[i] Sartor O, de Bono J, Chi KN, Fizazi K et al. Lutetium-177-PSMA-617 for Metastatic Castration-Resistant Prostate Cancer. N Engl J Med. 2021 Sep 16;385(12):1091-1103.