What is Ga-68 PSMA PET/CT Technique Used in Prostate Cancer Imaging?

PSMA is a smart molecule used in both imaging and treatment of prostate cancer. Ga-68-PSMA PET/CT is the method used for imaging high-risk prostate cancer and detecting its spread to the body.

In cases with elevated PSA (biochemical recurrence) after prostate surgery or radiotherapy, higher rates of recurrence may be observed compared to MRI and bone scintigraphy. It is also the most sensitive method in the detection of spread (metastases) to lymph nodes, organs, and bones. Moreover, it is used to select patients suitable for Lu-177-PSMA treatment of metastatic and hormone-resistant prostate cancer. 

How to Apply Ga-68 PSMA PET-CT?

Patients are not exposed to very high radiation in this method. The duration of the process is 30-45 minutes. Sugar metabolism is examined in classical FDG/PET/BT imaging. Many cancers are imageable. However, it does not work very well in prostate cancer. PSMA PET/CT is used only for prostate cancer and is very effective. We use Ga-68 PSMA PET/CT imaging to locate and image tumor cells in the body at the molecular level.

What are the Uses of Ga-68 PSMA?

Ga-68 is used in the following situations:

• Initial staging of intermediate and high-risk prostate cancer,
• In case of PSA recurrence (>0.2ng/ml) after radical prostatectomy / radiotherapy,
• Presence of suspicious lesions in other methods,
• Lu-177-PSMA (Lutesium) treatment planning,
• Radiotherapy planning,
• Treatment response research.

When Is Lutetium (Lu-177-PSMA) Treatment Used in Prostate Cancer?

Lu-177-PSMA (Lutesium) therapy has been used as a new treatment option in the treatment of metastatic and hormone-resistant prostate cancer in recent years. It is a smart molecule that locates prostate cancer cells in the body and enters them. It kills the cancer cell by irradiating them inside them. In this way, while affecting tumors, it makes very little irradiation to the surrounding healthy tissues. Damage to healthy tissues remains very low. For this reason, this treatment is called (target-oriented therapy marked with smart molecules) / (smart molecule marked target-oriented therapy).

PSA values decrease by more than 50 percent in approximately half of the cases after Lu-177-PSMA treatment. The patient does not feel any side effects during the treatment. A partial decrease in the functions of the salivary glands can be observed after the treatment.

How is Lutetium (Lu-177-PSMA) Treatment Applied in Prostate Cancer?

Lutetium 177 PSMA treatment is usually administered in 3 or 4 cycles at 6–8-week intervals. It can be applied up to 8-10 cycles according to the course of the disease, kidney functions, blood values, and special calculations. Patients suitable for treatment are determined by being examined by experienced nuclear medicine specialists. This treatment is given to the patients by slow infusions of between 20 and 30 times in a protected private room, under the supervision of experienced medical personnel, nurses, and doctors.