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.

PRRT Treatment Day Overview

Summary (10 sec read)

A typical PRRT (Peptide Receptor Radionuclide Therapy) treatment day for Neuroendocrine Tumor (NET) patients involves several steps. The night before and morning of the treatment, patients can eat normally but should avoid overindulgence and dehydration. On the treatment day, patients arrive in the morning, change into special attire to avoid radiation contamination, and receive room and bed orientation. Absorbent pads are placed throughout the room as a precaution against radioactive spills.

Before infusion, the nursing staff checks vitals and reviews the patient's medical history. A peripheral IV catheter is placed in the patient's arm for temporary use. The Radiation Safety Team briefs the patient on safety protocols.

The infusion process has three parts: first, anti-emetics are given to prevent nausea; second, an amino acid solution is administered to protect the kidneys from radioactivity; third, the Lu177 (Lutathera) infusion begins, mixed with saline and amino acid solutions. The entire process takes about 4-5 hours.

After infusion, the patient is monitored for symptoms for 1-2 hours. A discharge summary is provided, detailing the amount of Lu177 given, safety instructions, important contacts, and follow-up guidelines. This overview helps patients and caregivers understand the PRRT process and manage expectations.

PRRT Treatment Day Overview

How Does A Typical PRRT Day Look Like?

This is an overview of the Treatment Day for a Neuroendocrine Tumor (NET) patient receiving PRRT (Peptide Receptor Radionuclide Therapy).

This overview provides the patient and the caregiver a peek at what to expect during a typical PRRT treatment with Lu177 (Lutathera) and it covers the following aspects of a typical PRRT treatment day:

The night before and/ or the morning of the treatment day (infusion)
Before infusion
Infusion
After infusion & discharge from the hospital

1. The night before and the morning of each infusion:

Many a patients and caregivers ask about whether or not the patient needs to follow any dietary restrictions. The straight forward answer to this question is a “No!”

The patient can eat anything (s)he likes and this could include wine/ spirits during dinner time. The only advise that doctors give is, not to over indulge and get dehydrated. Also, during breakfast, the patient can eat anything that (s)he wants. It is advised that patients shouldn’t come on an empty stomach and at the same time doctors also talk of avoiding a heavy breakfast.

2. Treatment Day - Before infusion:

Patients are usually asked to come in the morning. After checking-in at the hospital, the patient is asked to change into a different attire because the treatment/ infusion involves radioactive material and this ensures that the patient’s clothing is free from radiation.

The patient is then taken to a different room for infusion. Here the patient receives room and bed orientation and is briefed about the treatment process. You will notice that absorbent pads placed on the floor throughout the room. This is a precautionary measure that’s taken in case of a radioactive spill. Moreover, the pads make the process of cleaning of the room far easier after the treatment is administered.

Before the infusion, the nursing staff from the hospital take the patient’s vitals, such as, height, weight, blood pressure, heart rate, respiration rate, temperature etc. These vitals are constantly monitored during the treatment process.

Post this, the team of doctors at the center review the patient’s medical, surgical and/ or medication history. This is usually followed up with a physical exam or a review of the body’s systems.

The nursing staff then places a peripheral IV catheter into a vein in the arm. This is temporary and is removed once the patient is discharged.

The patient is then briefed about the various “Do’s & Don’ts” by the Radiation Safety Team. This information is also provided to the patient as a part of the discharge summary.

3. Treatment Day – Infusion:

The PRRT treatment has three main parts:

Part 1: Anti-emetics or anti-nausea are given first because nausea (with or without vomiting) is one of the most common side-effects of the amino acid solution. Anti-emetics are given to help lessen these symptoms. This part usually begins about 15 mins before the amino acid solution is administered.

Part 2: The amino acid solution is administered second. The amino acid solution provides protection to the kidney from the radioactivity effects of Lu177 (Lutathera). The part usually begins about 30 mins before the Lu177 is administered.

Before administering the Lu177, one of the doctors will discuss the infusion procedure with the patient and answer any questions that the patient might have. The patient, here needs to sign a consent form that states that the patient agrees to receive the treatment.

Part 3: Lu177 (Lutathera) is given third and it takes about 30 minutes for the Lu177 to be fully infused. This is usually given along with the amino acid solution and this part begins about 30-45 mins after the amino acid solution has started.

How the Infusion Happens: A saline (NaCl) solution goes into a vial that contains the Lu177 (Lutathera) medication. This vial is contained in a lead container so as to avoid the harmful effects of radioactivity. From this vial, the mixture of Lu177 and NaCl is further mixed with the amino acid solution before being administered to the patient.

The total volume of amino acid solution given is about 2 litres and it takes about 4-5 hours for the bag to be empty.

During this entire three-part process, the patient is constantly monitored and managed for any symptoms. The team of doctors adjust the infusion rate of the amino acid solution if needed, and give rescue anti-emetics as and when required. There are, in some cases, some other mild symptoms, such as. Headaches, which are managed by the nursing staff.

4. After Infusion:

The patient is usually monitored for any symptoms for an hour or two post infusion.

All patients are provided a discharge summary that summarises the amount of Lu177 given, the “Do’s & Don’ts” following PRRT treatment, important telephone numbers and follow-up instructions.