177Lu-PSMA Therapy – 150 to 200 mCi is an advanced PSMA PET-based targeted radionuclide therapy for selected prostate cancer patients with PSMA-positive tumours, particularly those with advanced, metastatic, or treatment-resistant prostate cancer (PRC). This therapy takes advantage of a radiolabeled molecule called lutetium-177 PSMA that specifically targets Prostate-Specific Membrane Antigen (PSMA) in prostate cancer cells and beams radiation at the location of the tumour.

Dr. Nikunj Jain, Molecular Diagnostics and Therapy, gives you expert insights into patient selection, PSMA evaluation of imaging, therapy planning, and personalised radionuclide treatment. The approach to treatment is tailored to the extent of disease, prior treatment history, renal function, blood counts, and patient status, as determined by PSMA PET CT.

177Lu-PSMA therapy is part of targeted treatment, also referred to as radioligand therapy. The PSMA-targeting molecule is specific to prostate cancer cells, and when attached to radioactive Lutetium-177, the radiation can help destroy prostate cancers while minimizing exposure to many of the other healthy tissues in the body. The dose given for the therapeutic activity is between 150-200 mCi, depending on the tumour burden, treatment response, organ function, and based on the protocol chosen by your Nuclear Medicine specialist.

What is 177Lu-PSMA Therapy?

Targeted Molecular Therapies (177LU-PSMA Therapy): These therapies target a molecule (PSMA) found on the prostate tumor cells to which is attached a radioactive isotope (Lutetium-177). The therapy aims to target and kill prostate cancer cells with PSMA receptors. This therapy helps in:

• Targeted destruction of PSMA-positive prostate cancer cells.

• Treatment of advanced metastatic prostate cancer.

• Reduction of tumour activity and disease progression.

• Management of cancer spread to bones and other organs.

• Providing a personalised treatment option based on molecular imaging.

• Delivering radiation directly to cancer cells.

Before therapy, a PSMA PET CT scan is usually performed to confirm PSMA expression and determine whether the patient is suitable for treatment.

Why is the 150 to 200 mCi Dose Used?

A therapeutic activity of 150 to 200 mCi may be selected based on:

• Extent of prostate cancer spread.

• PSMA uptake seen on PET CT imaging.

• Previous cancer treatments.

• Response to earlier therapies.

• Kidney function.

• Bone marrow reserve.

• Overall health status of the patient.

The final therapeutic dose and number of cycles are decided by the Nuclear Medicine specialist after complete clinical evaluation.

Conditions Where 177Lu-PSMA Therapy May Be Considered

177Lu-PSMA therapy is mainly considered for patients with PSMA-positive prostate cancer, including:

Metastatic Castration-Resistant Prostate Cancer (mCRPC)

Helps treat prostate cancer that has progressed despite standard hormonal therapies.

Bone Metastatic Prostate Cancer

May help target prostate cancer deposits in bones showing PSMA expression.

Lymph Node Metastatic Disease

Can be considered for selected patients with PSMA-positive lymph node involvement.

Advanced Prostate Cancer

Provides a targeted treatment option for patients requiring additional therapeutic approaches after previous treatments.

Preparation Before 177Lu-PSMA Therapy

Proper preparation is important to ensure safe and effective therapy.

1. PSMA PET CT Evaluation

Before treatment, the Nuclear Medicine team evaluates:

• PSMA PET CT findings.

• PSMA expression in tumour sites.

• Distribution and extent of disease.

• Suitability for radionuclide therapy.

This imaging helps confirm that cancer cells can effectively take up the PSMA-targeted therapy.

2. Blood Tests and Organ Function Assessment

Before therapy, patients may require:

• Complete blood count (CBC).

• Kidney function tests.

• Liver function tests.

• Serum creatinine evaluation.

• Other investigations as advised.

Kidney and bone marrow assessment are important because these organs may receive radiation exposure.

3. Medication Review

Inform your doctor about:

• Current medications.

• Hormonal therapy.

• Chemotherapy history.

• Supplements.

• Allergies.

• Previous radiation treatments.

Your Nuclear Medicine specialist will provide specific instructions according to your condition.

How is 177Lu-PSMA Therapy (150 to 200 mCi) Administered?

The therapy is administered through an intravenous injection under the supervision of Nuclear Medicine specialists. Key points include:

• The prescribed Lutetium-177 PSMA radiopharmaceutical is administered through a vein.

• The compound travels through the bloodstream.

• It binds specifically to PSMA-expressing prostate cancer cells.

• Radiation is released directly at tumour sites.

• Cancer cells receive targeted radiation damage.

• The patient is monitored before discharge.

The treatment duration depends on preparation, administration, and observation requirements.

Post-Therapy Safety Instructions

After receiving 177Lu-PSMA therapy, radiation safety precautions are recommended to reduce unnecessary radiation exposure to others. Patients may be advised to:

• Drink plenty of fluids to help remove excess radioactive material.

• Follow radiation safety instructions provided by the Nuclear Medicine team.

• Maintain distance from pregnant women and small children for the advised duration.

• Maintain good personal hygiene.

• Wash hands frequently.

• Follow toilet safety instructions.

• Avoid prolonged close contact when advised.

The Nuclear Medicine team provides personalised safety instructions according to the administered activity.

Follow-Up After 177Lu-PSMA Therapy

Regular monitoring helps assess treatment response and safety. Follow-up may include:

• PSA blood tests to monitor tumour response.

• Complete blood count monitoring.

• Kidney function evaluation.

• Follow-up PSMA PET CT or other imaging studies.

• Assessment of symptoms and treatment response.

The number of treatment cycles and follow-up schedule depend on disease response and the doctor's recommendation.

Benefits of 177Lu-PSMA Therapy (150 to 200 mCi)

• Targeted treatment for PSMA-positive prostate cancer.

• Delivers radiation directly to cancer cells.

• Helps manage advanced metastatic prostate cancer.

• Provides an option for patients with progressive disease.

• Uses molecular imaging for personalised treatment planning.

• May reduce tumour-related symptoms.

• Limits radiation exposure to many normal tissues.

Possible Side Effects

Side effects may vary depending on treatment dose, number of cycles, and patient condition. Possible side effects include:

• Fatigue

• Nausea

• Reduced appetite

• Dry mouth

• Temporary reduction in blood cell counts

• Changes in kidney function

• Mild weakness

• Temporary changes in taste

The Nuclear Medicine team closely monitors patients and provides appropriate management recommendations.

Conclusion

177Lu-PSMA Therapy – 150 to 200 mCi is an advanced, individualised therapy, which represents a targeted radionuclide drug that is used for those patients who have advanced prostate cancer that is PSMA-positive. It offers molecular targeting plus radiation, so it can target the prostate cancer while sparing surrounding healthy tissue.

Achieving the most optimal outcome depends on proper patient selection, achieved with PSMA-PET CT imaging, laboratory evaluation, and expert treatment planning. Dr. Nikunj Jain, Molecular Diagnostics and Therapy, offers a complete evaluation, therapy planning, and tailored guidance process throughout the entire 177Lu-PSMA Therapy journey.