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.

TARE vs TACE for Hepatocellular Carcinoma and NET patients

Summary (10 sec read)

The incidence of Hepatocellular Carcinoma (HCC) has been increasing, with traditional treatment often involving Transarterial Chemoembolization (TACE). However, Transarterial Radioembolization (TARE) is gaining prominence for treating unresectable HCC due to its potential advantages. Studies demonstrate TARE's overall survival benefit, improved quality of life, and better toxicity profile compared to TACE. TARE's smaller particles make it suitable for patients with advanced liver disease, multifocal disease, vascular invasion, and portal vein thrombosis, reducing ischemia and necrosis risks seen with TACE.

TARE is also associated with a lower risk of post-embolization syndrome and is generally better tolerated, unlike TACE, which often causes liver function deterioration, pain, and fever. For early-stage HCC patients who are not candidates for radiofrequency ablation, TARE provides better response rates, tumor control, and survival outcomes. In Neuroendocrine Tumor (NET) patients with multiple liver lesions or tumors lacking somatostatin receptors, TARE is preferred over TACE.

Despite TARE's higher initial cost, its overall cost-effectiveness is superior due to fewer hospital admissions, reduced pain management needs, and lower treatment multiplicity and toxicity. TARE thus offers significant benefits for advanced liver disease, presenting a favorable side-effects profile and better cost-efficiency compared to TACE.

The incidence of Hepatocellular Carcinoma or HCC has been increasing over the past several years and several studies have projected that the incidence of HCC will continue to rise in the coming years.

Transarterial Chemoembolisation or TACE has been the initial treatment modality for HCC and has a huge body of evidence from several studies and clinical trials. Therefore, for long TACE has been a preferred treatment algorithm for unresectable HCC.

However, as the experience of Transarterial Radioembolisation or TARE has evolved, it is playing an increasingly important role in the treatment of unresectable HCC. Studies and trials have shown that TARE has many potential advantages over TACE and there is now substantial evidence to favor TARE over TACE.

The many potential advantages of TARE when compared with TACE are as below:

Several studies have shown a statistically significant overall survival advantage with TARE as compared to TACE.
TARE has better health-related quality-of-life metrics and toxicity profile when compared with TACE.
TARE as a much wider range of applications, including use in patients with more advanced liver disease, multi-focal disease, vascular invasion and portal vein thrombosis. Actually, TARE is more suitable for patients of HCC with portal vein thrombosis because of the small size of TARE particles when compared with TACE, which tends to induce more ischemia and necrosis.
Studies have also shown a much-lower risk of post-embolisation syndrome with TARE as compared with TACE.

In terms of side-effects, TARE is overall well-tolerated, whereas post-TACE, there is deterioration of the liver function coupled with pain and fever.
In patients with early-stage HCC and preserved liver function who are not candidates for radiofrequency ablation, TARE provides better response rates, tumor control and survival outcomes.
In Neuroendocrine Tumor (NET) patients with multiple lesions in both the lobes of the liver, TARE is a preferred modality and TACE is not recommended at all.
Also, in NET patients where the tumor does not express somatostatin receptors, TARE is a much better treatment technique as compared to TACE.
When it comes to cost, the upfront cost of a single TARE session is much higher (at least two to three times higher) than the cost of a single TACE session. However, considering the cost of hospital admission, pain control, treatment multiplicity and toxicity, the overall cost-effectiveness of TARE is likely to be superior to TACE in patients with unresectable HCC.

In terms of overall survival and delay of progression in patients with unresectable HCC, TARE is as efficacious as TACE, however TARE has an evolving role to play in the treatment of HCC with more advanced liver disease, multi-focal disease, vascular invasion and portal vein thrombosis. Apart from these reasons, a more favorable side-effects profile and cost are the other potential advantages of TARE as compared to TACE.

In terms of overall survival and delay of progression in patients with unresectable HCC, TARE is as efficacious as TACE, however TARE has an evolving role to play in the treatment of HCC with more advanced liver

disease, multi-focal disease, vascular invasion and portal vein thrombosis. Apart from these reasons, a more favorable side-effects profile and cost are the other potential advantages of TARE as compared to TACE.