Treatment of Patients With Progressive mCRPC With 177Lu-PSMA-617

Inclusion Criteria: 1. Ability to understand and sign an informed consent form (ICF). 2. Willingness and ability to comply with study requirements. 3. Age ≥18 years. 4. Presence of skeletal metastases with a superscan pattern on a 99mTc-MDP/HDP bone scan, defined by significantly increased skeletal radioisotope uptake relative to soft tissues and faint or absent renal activity. 5. Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2. 6. Hemoglobin ≥9.0 g/dL. 7. Platelet count ≥90 × 10⁹/L. 8. White blood cell count ≥2.0 × 10⁹/L, absolute neutrophil count (ANC) \>1.5 × 10⁹/L. o These hematologic criteria must be met without recent transfusions (within 28 days prior to the first study treatment) or growth factor support (within 21 days). 9. Serum/plasma creatinine ≤1.5 × upper limit of normal (ULN). 10. Histological, pathological, or cytological confirmation of prostate cancer. 11. Positive PSMA PET/CT scan showing at least one PSMA-positive metastatic lesion. 12. Castrate-level serum/plasma testosterone (\<50 ng/dL or \<1.7 nmol/L). 13. Prior treatment with at least one androgen receptor-axis-targeted therapy (ARAT). Exclusion Criteria: 1. Prior treatment with radiopharmaceuticals (e.g., Strontium-89, Samarium-153, Rhenium- 186, Rhenium-188, Radium-223, hemi-body irradiation) within six months before start of treatment under this protocol. 2. Prior PSMA-targeted radioligand therapy. 3. Systemic anti-cancer therapy (e.g., chemotherapy, immunotherapy, monoclonal antibodies) within four weeks before screening visit. 4. Known hypersensitivity to PLUVICTO or its components. 5. Concurrent treatment with other cytotoxic chemotherapy, immunotherapy, radioligand therapy, or investigational therapy. 6. Renal impairment (estimated glomerular filtration rate \<60 mL/min), hemoglobin \<9 g/dL, ANC \<1.5 × 10⁹/L, or platelets \< 90 × 10⁹/L. 7. History of CNS metastases unless treated and stable for 6 months, with no ongoing corticosteroid use. 8. Symptomatic or impending spinal cord compression. 9. Other malignancies impacting life expectancy or interfering with study assessments. Exceptions include non-melanoma skin cancer or superficial bladder cancer that has been adequately treated. 10. Major surgery within 30 days prior to enrollment. 11. Plans to conceive or father a child during treatment and up to six months post-treatment.