What is Lu PSMA (Lutetium-Prostate Specific Membrane Antigen) Therapy?

Lu177 PSMA Therapy is a treatment for patients with prostate cancer, especially those who have become refractory to conventional therapy. Lutetium PSMA therapy helps to slow down the growth of the cancer cells, reduce the size of the tumours and most importantly improve the quality of life of the patients by reducing the pain caused by the cancer.

Many prostate cancers, in particular those that have spread or become resistant to hormonal therapies, express a unique receptor on their cell surface called Prostate Specific Membrane Antigen (PSMA). When Prostate Cancer metastasizes i.e. spreads to other parts of the body, the PSMA receptor is expressed over the sites of metastases as well.

How does Lu PSMA Therapy Work?

Lutetium-177 is a radioactive substance that emits beta radiation, a destructive kind of radiation. Lutetium-177 is bound to a small peptide which attaches to the PSMA receptor expressed on the cancer cell surface. The Lutetium 177 – PSMA complex, thus attached to the prostate cancer cell, then emits killing radiation causing cell death of the cancer cell. Since the penetration of the emitted beta particle is very small, the surrounding normal cells are spared.

How is the Therapy Done?

Lu177 PSMA is administered intravenously. The patient is admitted to the hospital for 24 hours. A kidney function scan called a MAG3/EC scan is done prior to the administration of the Lu177 PSMA.

What are the Side Effects of Lu PSMA Therapy?

Lu177 PSMA is well tolerated. The most common side effects are a slightly dry mouth, fatigue and nausea. There may also be a slight fall in the white blood cells and platelets about 2 – 3 weeks after the Lu177 PSMA administration.

What is the Response Rate With Lu PSMA Therapy?

The response rates of Lu177 PSMA depend on the tumour biology of prostate cancer, the initial Gleason Score, the extent of disease and the responses to prior therapies. Typically, more than 70% of patients demonstrate a reduction in S. PSA and a shrinkage of tumours following Lu177 PSMA therapy.

When would the doctor consider using this Therapy?

Lu PSMA Therapy is a very specific therapy and is used for managing metastatic Prostate Cancer or when Prostate Cancer is no longer responsive to other types of treatment.

What are the Treatment Schedules with Lu PSMA Therapy?

Most patients undergo three-four treatment cycles at intervals of 8-12 weeks. The number of cycles and the interim duration may vary between individuals depending on the response and interim assessments.

Why should I choose the nuclear medicine therapy center at Fortis Memorial & Research Institute (FMRI), Gurugram (Haryana, India)?

The Nuclear Medicine Therapy Centre at FMRI was one of the first institutes to offer Radio-ligand Therapy with Lu PSMA, and today, the center receives patients from the country and from across the world.

Which Patients can benefit with PRRT?

Summary (10 sec read)

Peptide Receptor Radionuclide Therapy (PRRT) is a molecular therapy effective for treating Neuroendocrine Tumors (NETs). It involves creating a radiopeptide by combining a cell-targeting protein with a radioactive material, typically Yttrium-90 (Y90) or Lutetium-177 (Lu177). This radiopeptide, similar to the hormone somatostatin, is injected into the patient's bloodstream. It binds specifically to somatostatin receptors on tumor cells, delivering high doses of radiation directly to cancer cells, causing structural damage and cell death.

PRRT is particularly useful for patients with advanced, metastatic, or progressive NETs that are positive on somatostatin receptor imaging (e.g., Ga68-DOTATATE PET CT). It is recommended for patients who are ineligible for surgery or unresponsive to other treatments. PRRT aims to relieve symptoms, slow or stop tumor progression, and improve survival and quality of life.

At the Nuclear Medicine Centre in Gurgaon, India, two types of lab-made somatostatin receptors, DOTATOC and DOTATATE, are used in PRRT. The treatment process is meticulously handled by trained Nuclear Medicine Physicians to ensure efficacy and safety.

Innovation in Nuclear Medicine Therapy, all you need to know about PRRT.

PRRT is a short form for Peptide Receptor Radionuclide Therapy. It is also known as molecular therapy or radioisotope therapy. PRRT has been found to be very effective in the treatment on certain cancers called Neuro endocrine tumours or NETs as some of you may know them.

PRRT is an integral part of Nuclear Medicine Therapy and when a PRRT is conducted, the following steps are carefully undertaken and reviewed by trained Nuclear Medicine Physicians.

A cell targeting protein or peptide is combined with a Radioactive Material, creating a Radio Peptide. This cell targeting peptide is similar to Somatostatin a naturally occurring hormone in the human body
This Radio peptide created with a combination of a Peptide and Radioactive Material is then injected in the patient’s blood stream
This radio peptide has a property to bind with the neuroendocrine tumour cells in the body of a patient. This is achieved because of a cell surface protein (Somatostatin Receptors) present in the tumour cells which have the property to bind to Somatostatin
This radio peptide has the capability to deliver high dosage of radiation directly to the cancer cells - this leads to structural changes in the tumour cells and ultimately killing them
There are two types of Somatostatin Receptors – which are made in the labs at our Nuclear Medicine Centre in Gurgaon India – These are DOTATOC and DOTATATE

This completes the fundamental steps of the PRRT process, now let’s also understand the radioactive chemicals (also called radionuclides) involved – this would help us understand the process a little deeper. So, which are these radionuclides?

Yttrium 90 (Y90) and Lutetium 177 (Lu177) are the most commonly used radionuclides.

Now let’s understand what conditions can be treated by PRRT?

PRRT, like we mentioned earlier, is a procedure that is used for treating Neuroendocrine Tumours (NETs) – gastro-entero-pancreatic NETs, which arise from the stomach, gastrointestinal tract, pancreas, islet cell carcinomas of the pancreas (These NETs are included in the US Federal Drug Administration {FDA} approved indication)

PRRT is a recommended option for patients typically with the following conditions:

Patients with Advanced Metastatic or progressive NETs which are positive on Somatostatin Receptor Imaging (Ga68-DOTATATE PET CT or other equivalent scans your Doctor may recommend)
Patients without options for Surgery
Patients who are not responding to other therapies

The objective of PRRT therapy is symptom relief, slow down or stoppage of tumour progression and to improve survival and quality of life.

If you find this article informative please leave a word in the comment section below. Don't forget to check the rest part of the blog "Is PRRT Safe for you?" For more information do call us at +91 98111 27080 or write to us at info@nuclearmedicinetherapy.in.