PRLT

PSMA-targeted Radioligand Therapy (PRLT) is a form of molecular targeted therapy that is performed by using the prostate-specific membrane antigen coupled with a radionuclide emitting beta radiation. In this case the isotope Lutitium-177. 

PRLT is a realtively new novel nuclear medicine therapy.  This form of therapy was first applied to metatstatic prostate tumors at Bad Berka in 2013.

How Does PRLT Work? 

The metastatic prostate cancer produces a Prostate-Specific Membrane Antigen (PSMA) ligand. Ligands are small molecules that transmit signals in between or within cells. The ligand is important because it facilitates the binding to cellular proteins that become receptors that absorb an isotope.  

For therapy, the PSMA ligand is attached to the radioisotope Lutetium-177 and infused into the body. The PSMA that is part of the prostate cancer tumors acts like

The Effects of Lu-177 PSMA-PRLT from April 2013 to April 2016.

Over the course of three years at Bad Berka, 119 metastatic castration-resistant prostate cancer patients were treated with 300 total cycles of PRLT. Patients received from 1 to 7 cycles. Bone mets were present in 81% of patients, 71% presented with lymph node mets and 16% presented with visceral mets.

Patients who had at least one cycle of PRLT (80 patients) experienced a reduction of the PSA level. Some 61 patients had a

The experience of using PRLT with a Lu-177-labelled small molecule targeting PSMA began in April 2013. This approach using the PSMA ligands to target systemic therapy proved to be successful for treating Metastatic Castration-Resistant Prostate Cancer, especially after the exhaustion of conventional therapies.

Please consult the Journal of Nuclear Medicine 2016 for the details of the comprehensive study from the April 2013 to April 2016 time period.  This paper can be downloaded from this

Possible Risk Factors to Consider Before PRLT

One of the first factors for risk to be considered is a patient’s bone marrow condition in the event there is severe bone marrow depression due to the following:

  • Disseminated metastases
  • Previous irradiation of spine or pelvis
  • Concurrent chemotherapy – allow 6 wk before PRLT
  • Getting Ra-223 therapy – allow 2-3 months before PRLT

Other risk factors to consider:

If patient has severe anemia – correct with transfusion

As a patient considering PRLT at Bad Berka, you need to know that there are two essential inclusion criteria that are recommended by the German Society of Nuclear Medicine:

1) Distant metastases with high PSMA expression as confirmed on pre-therapy Ga-68-PSMA-PET/CT and

2) progressive disease despite extensive previous treatments.

There are other considerations too. Please see risks in the section on PRLT Risks.