[PSMA-radioguided surgery in localized recurrent prostate cancer : Current and future aspects]

Recently, PSMA-radioguided surgery (PSMA-RGS) was introduced for targeted resection of localized prostate cancer recurrence. Prerequisite for preoperative patient selection and localization of tumor recurrence is a positive ⁶⁸Ga-HBED-CC PSMA positron emission tomography (PET) scan with preferably only singular soft tissue or lymph node recurrence. After injection of In-PSMA I&T or Tc-PSMA-I&S single photon emission computer tomography (SPECT)/computer tomography (CT) examination is performed in every patient to verify radiotracer uptake in tumor lesions. In a preliminary study, ¹¹¹In-PSMA I&T SPECT/CT could detect about half of the ⁶⁸Ga-HBED-CC PSMA PET-positive lesions, while nearly all PET-positive lesions could be detected using PSMA-RGS and also five additional lesions compared to ⁶⁸Ga-HBED-CC-PSMA PET. Follow-up data from 55 patients show a PSA reduction >50% and >90% in 44 (80%) and 29 (53%) patients, respectively. In 34 (62%) patients, a PSA drop to <0.2 ng/ml was observed. In all, 15 (27%) patients received further PC-specific treatment; the remaining 40 (73%) patients did not undergo further treatment. In 33% of patients, surgery-related complications were noted; however, most were regarded as minor. Thus, PSMA-RGS seems to be of high value in patients with localized prostate cancer recurrence with exact localization and resection of metastatic tissue. However, patient selection based on ⁶⁸Ga-PSMA PET imaging and clinical parameters is crucial to obtain satisfactory oncological results.