Peptide Receptor Radionuclide Therapy (PRRT) in prostate cancer

Newsid: 1066    Date: Jan 20, 2017

Inclusion criteria for RLT with Lu-PSMA

• metastatic castrate resistant prostate cancer with PSMA positive metastatic disease upon PSMA-PET or SPECT imaging
• after initial hormone therapy (LH-RH agonists / antagonists) and
o progressive disease despite newly developed hormone therapies (abiraterone / enzalutamide)
o progressive disease despite (first line or second line) chemotherapy (Docetaxel and Cabecitaxel) or patient not suitable for chemotherapy
• not suitable for Ra-223-dichloride due to extraosseous metastases or diffuse bone marrow metastases
• decision for salvage therapy at the institutional interdisciplinary tumor board / after urooncological counseling

Preparation prior RLT and exclusion criteria

• PSMA-PET or SPECT imaging to verify PSMA positive lesions
• Renal scintigraphy to evaluate renal function and rule out obstructive dysfunctions, in the case of obstructive dysfunction, it should be treated first

Exclusion criteria

• WBC ≤ 2 Tsd./µl.
• Hb ≤ 8 g/dl, in the case of symptomatic anaemia a red-blood-cell transfusion should be preceded the therapy. RLT with Lu-PSMA may have an positive effect on bone marrow depression causes less blood transfusion because of tumor regression in bone marrow[19]
• Platelets ≤ 75 x 109/l
• Creatinine > 2 mg/dl
• ECOG > 2

Proposed Protocol

• Cooling the salivary glands from 30 min. before and up to 4 hours after the Lu-PSMA injection for reducing the risk of salivary glands radiation injuries
• Using urinary catheter in incontinent patients in the first 48 hours for avoiding any contamination
• A dose of 6 GBq (range : 5.5 – 6.5 GBq) 177Lutetium-PSMA-617
• Injection intravenously as a slow bolus (over about 30 seconds) followed by 1000 ml Ringer or NaCl
• 3 – 5 cycles of the RLT every 8 weeks
At least one whole body scan 24-48 hours p.i. (preferably with SPECT(/CT))
For dosimetry purpose whole body scan should be obtained directly 10 Minutes p.i. and 24, 48 and one scan 7 to 10 days p.i. as far as possible

Evaluation after RLT

• PSMA-PET or SPECT imaging before first and after second cycle (interim PSMA-imaging optional)
• Decision to pursue the RLT depending on the imaging and clinical situation